View Full Version : barrel roll in 172
Andrey Serbinenko
July 20th 06, 06:34 AM
If kept within the normal category load limits, is 172 certified to do
barrel rolls?
Andrey
tony roberts[_1_]
July 20th 06, 06:39 AM
No
-- 
Tony Roberts
PP-ASEL
VFR OTT
Night
Cessna 172H C-GICE
In article >,
 Andrey Serbinenko > wrote:
> If kept within the normal category load limits, is 172 certified to do
> barrel rolls?
> 
> Andrey
Jim Macklin
July 20th 06, 06:51 AM
no
"Andrey Serbinenko" > wrote in 
message ...
|
| If kept within the normal category load limits, is 172 
certified to do
| barrel rolls?
|
| Andrey
Uli
July 20th 06, 08:14 AM
explaination: normal category limits angle of bank to 60 degrees, utility
category's limit is 90 degrees. 
see FAR 23.3 (US) or CS-23.3 (EU) or POH for more details...
uli
> If kept within the normal category load limits, is 172 certified to do
> barrel rolls?
Dudley Henriques[_1_]
July 20th 06, 03:37 PM
"Andrey Serbinenko" > wrote in message 
...
>
> If kept within the normal category load limits, is 172 certified to do
> barrel rolls?
>
> Andrey
The short answer to your question is no.
The long answer to your question is also no.
Dudley Henriques
Aerobatic Instructor (Retired)
Peter R.
July 20th 06, 03:46 PM
Dudley Henriques > wrote:
> The short answer to your question is no.
> The long answer to your question is also no.
That's about the long and short of it.
-- 
Peter 
Haven't used that lame joke since my racketball days.
john smith
July 20th 06, 03:55 PM
In article >,
 Andrey Serbinenko > wrote:
> If kept within the normal category load limits, is 172 certified to do
> barrel rolls?
Certified? No.
Possible? Yes, but you will finish much lower than where you started.
Jim Macklin
July 20th 06, 04:09 PM
Didn't Lorena Bobbitt say that?
"Peter R." > wrote in message 
...
|snip
| That's about the long and short of it.
|
| -- 
| Peter
| Haven't used that lame joke since my racketball days.
Bob Moore
July 20th 06, 04:18 PM
Morgans wrote
> I'll bet he is not going to wear a parachute, either, which is
> required. 
Where does it say that?
> The answer to rolling a normal category plane should be no, always.
The C-172 that I fly is a Utility Category airplane, if I want it to be.
Bob Moore
ATP CFI
Stefan
July 20th 06, 04:37 PM
Morgans schrieb:
> Don't encourage that type of behavior with a yes. 
Where did he write that he wants top try it? He was just wondering.
> and a blown barrel roll could stall the plane,
Gee... and then fall out of the sky in pieces, I assume. I wonder what 
your comment would have been if a journalist had written this.
> I'll bet he is not going to wear a parachute, either, which is required.
No. As it's illegal to do barrel roll a 172, there can't be a legal 
requirement to wear a chute while doing so.
Stefan
Jim Macklin
July 20th 06, 04:51 PM
Utility category allows some limited acro maneuvers, and a
list of approved maneuvers is on the placard on the side
wall of the cabin and in the POH.  If you want to do rolls,
snap rolls, etc, rent or buy an airplane designed and tested
and certified as such.  Can the 172 do acro, sure, with Bob
Hoover doing the flying.  Can some ham handed 100 private
pilot do it with out falling out of the roll, and pulling 9
Gs in the recovery?  Probably not.
Parachutes are required when you exceed certain attitudes,
the mental attitude being the most important.
§ 91.303   Aerobatic flight.
No person may operate an aircraft in aerobatic flight-
(a) Over any congested area of a city, town, or settlement;
(b) Over an open air assembly of persons;
(c) Within the lateral boundaries of the surface areas of 
Class B, Class C, Class D, or Class E airspace designated 
for an airport;
(d) Within 4 nautical miles of the center line of any 
Federal airway;
(e) Below an altitude of 1,500 feet above the surface; or
(f) When flight visibility is less than 3 statute miles.
For the purposes of this section, aerobatic flight means an 
intentional maneuver involving an abrupt change in an 
aircraft's attitude, an abnormal attitude, or abnormal 
acceleration, not necessary for normal flight.
[Doc. No. 18834, 54 FR 34308, Aug. 18, 1989, as amended by 
Amdt. 91-227, 56 FR 65661, Dec. 17, 1991]
§ 91.307   Parachutes and parachuting.
(a) No pilot of a civil aircraft may allow a parachute that 
is available for emergency use to be carried in that 
aircraft unless it is an approved type and-
(1) If a chair type (canopy in back), it has been packed by 
a certificated and appropriately rated parachute rigger 
within the preceding 120 days; or
(2) If any other type, it has been packed by a certificated 
and appropriately rated parachute rigger-
(i) Within the preceding 120 days, if its canopy, shrouds, 
and harness are composed exclusively of nylon, rayon, or 
other similar synthetic fiber or materials that are 
substantially resistant to damage from mold, mildew, or 
other fungi and other rotting agents propagated in a moist 
environment; or
(ii) Within the preceding 60 days, if any part of the 
parachute is composed of silk, pongee, or other natural 
fiber, or materials not specified in paragraph (a)(2)(i) of 
this section.
(b) Except in an emergency, no pilot in command may allow, 
and no person may conduct, a parachute operation from an 
aircraft within the United States except in accordance with 
part 105 of this chapter.
(c) Unless each occupant of the aircraft is wearing an 
approved parachute, no pilot of a civil aircraft carrying 
any person (other than a crewmember) may execute any 
intentional maneuver that exceeds-
(1) A bank of 60 degrees relative to the horizon; or
(2) A nose-up or nose-down attitude of 30 degrees relative 
to the horizon.
(d) Paragraph (c) of this section does not apply to-
(1) Flight tests for pilot certification or rating; or
(2) Spins and other flight maneuvers required by the 
regulations for any certificate or rating when given by-
(i) A certificated flight instructor; or
(ii) An airline transport pilot instructing in accordance 
with §61.67 of this chapter.
(e) For the purposes of this section, approved parachute 
means-
(1) A parachute manufactured under a type certificate or a 
technical standard order (C-23 series); or
(2) A personnel-carrying military parachute identified by an 
NAF, AAF, or AN drawing number, an AAF order number, or any 
other military designation or specification number.
[Doc. No. 18334, 54 FR 34308, Aug. 18, 1989, as amended by 
Amdt. 91-255, 62 FR 68137, Dec. 30, 1997; Amdt. 91-268, 66 
FR 23553, May 9, 2001]
-- 
James H. Macklin
ATP,CFI,A&P
"Bob Moore" > wrote in message
. 122...
| Morgans wrote
| > I'll bet he is not going to wear a parachute, either,
which is
| > required.
|
| Where does it say that?
|
| > The answer to rolling a normal category plane should be
no, always.
|
| The C-172 that I fly is a Utility Category airplane, if I
want it to be.
|
| Bob Moore
| ATP CFI
Morgans[_3_]
July 20th 06, 04:59 PM
"john smith" > wrote
> Certified? No.
> Possible? Yes, but you will finish much lower than where you started.
Don't encourage that type of behavior with a yes.  If he had to ask, he is
probably not a competent aerobatic pilot, and a blown barrel roll could
stall the plane, or overstress it, so it fails then, or later.
I'll bet he is not going to wear a parachute, either, which is required.
The answer to rolling a normal category plane should be no, always.
We don't want his, or someone else's blood on our hands.
-- 
Jim in NC
Andrey Serbinenko
July 20th 06, 05:22 PM
> Don't encourage that type of behavior with a yes.  If he had to ask, he is
I'm slightly disappointed by how quickly you've assumed my complete
brainlessness. Yes I know what FARs say, and what POH says, and no, I'm
not going to read this newsgroup and go break my neck the next morning.
What I was hoping to hear was an opinion of someone who's familiar with
what is involved in test-flying for normal/utility category and how much
it covers the type of stress imposed on the airframe and systems in a barrel
roll.
Andrey
Andrey Serbinenko
July 20th 06, 05:25 PM
> Possible? Yes, but you will finish much lower than where you started.
So, basically it's just because of a low-hp engine that the maneuver
can't be properly executed?
Andrey
Stefan
July 20th 06, 05:29 PM
Andrey Serbinenko schrieb:
> I'm slightly disappointed by how quickly you've assumed my complete
> brainlessness.
If this surprizes you, then you don't read this group often.
Stefan
Jim Macklin
July 20th 06, 05:37 PM
A properly done mild acro maneuver is well within the limits 
of even a normal category airplane [3.8G], but it is easy to 
botch a maneuver and then the recovery can require much 
higher forces.  They only test using qualified and competent 
pilots and they only test for maneuvers they intend to 
certify the aircraft to do.
Some airplanes may be certified for "flick" maneuvers or 
accelerated  maneuvers entered at higher speeds, such as 
snap rolls.  Some aircraft are approved for unlimited 
maneuvers and they sometimes break.
see http://www.faa.gov/regulations_policies/faa_regulations/
§ 23.151   Acrobatic maneuvers.
Each acrobatic and utility category airplane must be able to 
perform safely the acrobatic maneuvers for which 
certification is requested. Safe entry speeds for these 
maneuvers must be determined.
Browse Previous | Browse Next
§ 23.221   Spinning.
(a) Normal category airplanes. A single-engine, normal 
category airplane must be able to recover from a one-turn 
spin or a three-second spin, whichever takes longer, in not 
more than one additional turn after initiation of the first 
control action for recovery, or demonstrate compliance with 
the optional spin resistant requirements of this section.
(1) The following apply to one turn or three second spins:
(i) For both the flaps-retracted and flaps-extended 
conditions, the applicable airspeed limit and positive limit 
maneuvering load factor must not be exceeded;
(ii) No control forces or characteristic encountered during 
the spin or recovery may adversely affect prompt recovery;
(iii) It must be impossible to obtain unrecoverable spins 
with any use of the flight or engine power controls either 
at the entry into or during the spin; and
(iv) For the flaps-extended condition, the flaps may be 
retracted during the recovery but not before rotation has 
ceased.
(2) At the applicant's option, the airplane may be 
demonstrated to be spin resistant by the following:
(i) During the stall maneuver contained in §23.201, the 
pitch control must be pulled back and held against the stop. 
Then, using ailerons and rudders in the proper direction, it 
must be possible to maintain wings-level flight within 15 
degrees of bank and to roll the airplane from a 30 degree 
bank in one direction to a 30 degree bank in the other 
direction;
(ii) Reduce the airplane speed using pitch control at a rate 
of approximately one knot per second until the pitch control 
reaches the stop; then, with the pitch control pulled back 
and held against the stop, apply full rudder control in a 
manner to promote spin entry for a period of seven seconds 
or through a 360 degree heading change, whichever occurs 
first. If the 360 degree heading change is reached first, it 
must have taken no fewer than four seconds. This maneuver 
must be performed first with the ailerons in the neutral 
position, and then with the ailerons deflected opposite the 
direction of turn in the most adverse manner. Power and 
airplane configuration must be set in accordance with 
§23.201(e) without change during the maneuver. At the end of 
seven seconds or a 360 degree heading change, the airplane 
must respond immediately and normally to primary flight 
controls applied to regain coordinated, unstalled flight 
without reversal of control effect and without exceeding the 
temporary control forces specified by §23.143(c); and
(iii) Compliance with §§23.201 and 23.203 must be 
demonstrated with the airplane in uncoordinated flight, 
corresponding to one ball width displacement on a slip-skid 
indicator, unless one ball width displacement cannot be 
obtained with full rudder, in which case the demonstration 
must be with full rudder applied.
(b) Utility category airplanes. A utility category airplane 
must meet the requirements of paragraph (a) of this section. 
In addition, the requirements of paragraph (c) of this 
section and §23.807(b)(7) must be met if approval for 
spinning is requested.
(c) Acrobatic category airplanes. An acrobatic category 
airplane must meet the spin requirements of paragraph (a) of 
this section and §23.807(b)(6). In addition, the following 
requirements must be met in each configuration for which 
approval for spinning is requested:
(1) The airplane must recover from any point in a spin up to 
and including six turns, or any greater number of turns for 
which certification is requested, in not more than one and 
one-half additional turns after initiation of the first 
control action for recovery. However, beyond three turns, 
the spin may be discontinued if spiral characteristics 
appear.
(2) The applicable airspeed limits and limit maneuvering 
load factors must not be exceeded. For flaps-extended 
configurations for which approval is requested, the flaps 
must not be retracted during the recovery.
(3) It must be impossible to obtain unrecoverable spins with 
any use of the flight or engine power controls either at the 
entry into or during the spin.
(4) There must be no characteristics during the spin (such 
as excessive rates of rotation or extreme oscillatory 
motion) that might prevent a successful recovery due to 
disorientation or incapacitation of the pilot.
[Doc. No. 27807, 61 FR 5191, Feb. 9, 1996]
"Andrey Serbinenko" > wrote in 
message ...
|> Don't encourage that type of behavior with a yes.  If he 
had to ask, he is
|
| I'm slightly disappointed by how quickly you've assumed my 
complete
| brainlessness. Yes I know what FARs say, and what POH 
says, and no, I'm
| not going to read this newsgroup and go break my neck the 
next morning.
| What I was hoping to hear was an opinion of someone who's 
familiar with
| what is involved in test-flying for normal/utility 
category and how much
| it covers the type of stress imposed on the airframe and 
systems in a barrel
| roll.
|
|
| Andrey
|
Jim Macklin
July 20th 06, 05:39 PM
No, poor pilot skill.
-- 
James H. Macklin
ATP,CFI,A&P
"Andrey Serbinenko" > wrote in 
message ...
|> Possible? Yes, but you will finish much lower than where 
you started.
|
| So, basically it's just because of a low-hp engine that 
the maneuver
| can't be properly executed?
|
|
|
| Andrey
Dale
July 20th 06, 05:49 PM
In article <kMMvg.78923$ZW3.78738@dukeread04>,
 "Jim Macklin" > wrote:
> 
> Parachutes are required when you exceed certain attitudes,
> the mental attitude being the most important.
Read it again.  Parachutes are not required if you're solo.
Bob Moore
July 20th 06, 05:53 PM
Andrey Serbinenko wrote
> I'm slightly disappointed by how quickly you've assumed my complete
> brainlessness. Yes I know what FARs say, and what POH says, and no,
> I'm not going to read this newsgroup and go break my neck the next
> morning. What I was hoping to hear was an opinion of someone who's
> familiar with what is involved in test-flying for normal/utility
> category and how much it covers the type of stress imposed on the
> airframe and systems in a barrel roll.
First Andrey, you will probably find much disagreement on this group
as to what actually constitues a "barrell roll". If conducted as 
normally accepted in the aerobatic community, it consists of a 
combination loop and roll which at most, places about 3g's on the 
airframe. The g loading is not the problem in the utility category C-
172, its lack of power to complete the loop portion is what makes it 
particularly difficult.
Below, I have copied a description of a "barrell roll". This may or may 
not be the maneuver that you have in mind.  It would obviously be much 
easier in one of the higher powered 172s than in the O-300, 145hp 
powered version that I fly.  :-)
After reading the following, you might find that you really didn't mean 
to say "barrell roll".   :-)  BTW the two following descriptions are how 
I was taught to perform the "barrell roll" in Navy flight training. :-)
From:
http://acro.harvard.edu
The Barrel Roll is a not competition maneuver.  The barrel roll is a 
combination between a loop and a roll. You complete one loop while 
completing one roll at the same time.
The flight path during a barrel roll has the shape of a horizontal cork 
screw. Imagine a big barrel, with the airplanes wheels rolling along the 
inside of the barrel in a cork screw path.
During a barrel roll, the pilot experiences always positive G's. The 
maximum is about 2.5 to 3 G, the minimum about 0.5 G.
And another description from Kershner's Flight Instructor's Manual:
THE BARREL ROLL
• Preparation. It's almost impossible to draw a barrel roll 
  on the chalkboard, but a model will give the desired results. 
  Have the trainee study the references.
•Explanation. The barrel roll is a precise maneuver in which
  the airplane is rolled around an imaginary point 45° to
  the original flight path. A positive-g level is maintained 
  throughout the maneuver, and the ball in the turn indicator 
  should stay in the middle.
    You may wonder why the barrel roll is taught this late, 
since it appears to be so simple. Well, it is a precise maneuver 
requiring particular airplane attitudes at particular reference 
points,  which is difficult for the average trainee to do properly
at first.
    This maneuver might be considered an exaggeration of the 
wingover,  but instead of starting to shallow the bank at the 90° 
position, the pilot  must steepen it continually until the airplane 
has rolled 360° and is back on the original heading. The rate of
roll must be much greater than that  used for the wingover 
because the airplane must be in a vertical bank at  45° of turn, 
and it must be inverted at 90° of turn. The roll and turn is 
continued until the airplane is headed in the original direction with 
the wings level. Compare the barrel roll in Fig. 23-12 with the 
same view of  the wingover in Fig. 20-7.
    From behind the maneuver looks as though the airplane is being
flown around the outside of a barrel. This is a very good maneuver
for gaining confidence and keeping oriented while flying inverted in
balanced flight. 
   Good coordination is required to do the barrel roll properly and 
the trainee will show an improvement in that area after a session of 
barrel rolls. 
   The barrel roll is generally more difficult and precise than the 
aileron roll, and he may have to work on this one awhile.
Why-
The barrel roll is one of the best maneuvers for improving orientation.
   Unlike the other acrobatic maneuvers covered thus far, the barrel 
roll requires a constantly changing bank and pitch (with attendant 
changing airspeed) and a radical change in heading (90°) while the 
airplane is rolling. The average trainee probably will be looking at the
wing tip at a time when he should be checking the nose, or vice versa.
When he is able to stay well oriented in the barrel roll, he is ready to
move on to the reverse Cuban eight or reverse cloverleaf.
How-
You might use the following explanation, or develop your own: 
(1) Make sure the area is clear, then pick a reference on the horizon
     off the wing tip as in the wingover and lazy eight. 
(2) Set the throttle to low cruise rpm and ease the nose over to pick-
      up about 10 K more than used for the wingover or set up the 
     airspeed used for a loop, whichever is higher. Power adjustment 
     should not be necessary during the maneuver. You might have
     some of your sharper trainees apply full power as the airplane 
     approaches inverted and then remind them to throttle back as the 
     airspeed picks up in the last part of the maneuver. 
(3) Smoothly pull the nose up and start a coordinated climbing turn 
     (note that it will have to be at a much faster rate than was used
     for the wingover) toward the reference point. (Assume that at first
     the roll will be to the left.) 
(4) When the nose is 45° from the original heading, it should be at its 
     highest pitch attitude and the left bank should be vertical. 
(5) When the nose is at 90° from the original heading, you should be
      looking directly at the reference point that was originally off 
the 
     wing tipfrom a completely inverted position (momentarily). 
(6) When the airplane heading is again 45° from the original, the bank
      is vertical but you will be in a right bank as far as the ground 
is 
      concerned; that is, the right wing is pointing straight down at 
this
      instant of roll. The nose will be at its lowest pitch attitude at 
this 
      point. 
(7) The roll is continued to wings-level flight as the nose is raised 
back
      to the cruise attitude.
The maneuver must be symmetrical; the nose must go as far above the
horizon as below. The barrel roll requires definite checkpoints to 
ensure
that the airplane is at the correct attitude throughout. It is 
interesting
to note that if the barrel roll is to the left, all of the airplane's 
path is to 
the left of the original line of flight and the airplane's nose is 
always 
pointed to the left of the original flight line (until it merges again 
at the 
completion of the maneuver). The opposite occurs, naturally, for the 
barrel roll to the right.
Another method of doing a barrel roll is to pick a reference on the 
horizon, turn the airplane 45° to the reference point, and proceed to 
make a wide roll around this real point. One disadvantage of this 
method for the newcomer is that it depends on the pilot's own 
judgment of how large the orbit around the point should be. For an 
introduction to the maneuver, the first method is usually better, but 
you 
may prefer the second and work out your own techniques of instructing 
it.
Demonstration.
    Try not to lose the reference point yourself while demonstrating
this one. You may find your explanation is not keeping up with the
airplane, which usually results in sputtering and stuttering while the
maneuver proceeds to its foregone conclusion -and then you have
to do a new demonstration. Don't worry, this will happen plenty of 
times during your career of instructing aerobatics -when your mouth
can't keep up with your brain or the maneuver-and it can ease tension 
if you react to it with humor.
Usually the trainee is surprised to see the same wing tip back on the
reference point and may confess that, like the first snap roll, the 
earth
and sky were blurred and he had no idea where the reference was 
during the maneuver.
Practice. 
You may rest assured the trainee will "lose" the reference point during 
the first couple of barrel rolls. He'll usually stare over the nose, 
seeing
nothing but blue sky or ground and not really seeing the point at all.
Common errors during barrel rolls include these:
1. Not pulling the nose high enough in the first 45° of the maneuver, 
    which means that the highest and lowest nose positions are not 
    symmetrical to the horizon.
2. Not maintaining a constant rate of roll. Usually things are fine at 
the
    45° position;  the nose is at its highest pitch and the bank is 
vertical.
    As you approach the position of 90° of turn you will probably find 
    that he is not going to be completely inverted at that point and 
will
    have to rush things a bit to make it. The usual reason is that he 
did 
    not maintain a constant rate of roll. Remember that the nose is up 
    and the airspeed is slower in this segment of the maneuver, so the 
    controls must be deflected more to get the same rate. This is where 
    coordination comes in. Watch for it in particular.
3. Letting the nose drop after passing the 90° point; losing too much 
    altitude and gaining excess airspeed.
4. Failure to roll out on the original heading; having the wing tip well 
    ahead, or well behind, the reference when the maneuver is completed.
Evaluation and Review.
    Review each barrel roll briefly in the air, and have the trainee use
the model on the ground. This one can be hard to "see," so go over it 
again as necessary after getting on the ground.
    By the time a half-dozen barrel rolls have been practiced, the 
average
trainee should be oriented throughout the maneuver even though he may
still have minor problems of heading and symmetry. After a dozen rolls
he should be starting to work on a constant roll rate and starting to 
ease
his heading problems. After several hundred, he may begin to be 
satisfied 
with his barrel rolls but will realize that constant practice is 
required.
john smith
July 20th 06, 05:57 PM
> > Possible? Yes, but you will finish much lower than where you started.
> So, basically it's just because of a low-hp engine that the maneuver
> can't be properly executed?
The answer is not that simple. Low horsepower engine is one, design and 
strength of the airframe is another, skill of the pilot is a third, 
design of the airfoils selected, design of the the control system, 
design of the engine systems, etc. Many factors contribute to "how" a 
maneuver can be flown.
Geez, Morgans, can't someone ask a simple question about whether an
aircraft can perform a roll without you jumping to the absurd
conclusion that he's going to run right out and do it?  There is such a
thing as "idle curiosity."
Take your meds and calm down.
AJ
Morgans wrote:
> "john smith" > wrote
>
> > Certified? No.
> > Possible? Yes, but you will finish much lower than where you started.
>
> Don't encourage that type of behavior with a yes.  If he had to ask, he is
> probably not a competent aerobatic pilot, and a blown barrel roll could
> stall the plane, or overstress it, so it fails then, or later.
>
> I'll bet he is not going to wear a parachute, either, which is required.
>
> The answer to rolling a normal category plane should be no, always.
>
> We don't want his, or someone else's blood on our hands.
> -- 
> Jim in NC
Jim Macklin
July 20th 06, 06:31 PM
Then why a C172 with 4 seats.  Fools always carry a witness.
"Dale" > wrote in message 
...
| In article <kMMvg.78923$ZW3.78738@dukeread04>,
| "Jim Macklin" > 
wrote:
|
| >
| > Parachutes are required when you exceed certain 
attitudes,
| > the mental attitude being the most important.
|
| Read it again.  Parachutes are not required if you're 
solo.
Dudley Henriques[_1_]
July 20th 06, 06:36 PM
"Andrey Serbinenko" > wrote in message 
...
>> Possible? Yes, but you will finish much lower than where you started.
>
> So, basically it's just because of a low-hp engine that the maneuver
> can't be properly executed?
>
>
>
> Andrey
Horsepower has absolutely nothing to do with the ability of an aircraft to 
do a barrel roll. Airspeed and energy are all that's required and this can 
be supplied even in an aircraft having no engine at all such as a glider or 
a sail plane.
It helps of course if you have horsepower, but horsepower simply allows for 
an entry into the roll from a higher nose attitude.
Also, barrel rolls can be done using various amounts of positive g as long 
as positive g is applied to the aircraft through the roll.
The problem in discussing this issue in the context of using a normal 
category airplane to do it, even considering the utility envelope if 
available on such an airplane, isn't whether or not the maneuver can be 
done. It's whether the pilot in such an airplane can keep the execution of 
the roll inside safe parameters.
I have done barrel rolls in demonstration many times, as have pilots like 
Bob Hoover, Bobby Bishop, and many others; not to mention Scotty McCray 
using a sail plane. The issue as I've said isn't whether or not it can be 
done in non aerobatic certificated airplanes. It most certainly can be done. 
The issue is that to do ANY aerobatic maneuver SAFELY in these airplanes, 
the maneuver has to be perfectly. There is little room for mistake or error. 
It is extremely easy due to the lack of aerobatic performance; ie roll rate 
and indeed "horsepower" to get these airplanes into extremely dangerous 
recovery situations if a maneuver is botched.
This is the reason why you will get the type of answers you have been 
getting on this newsgroup.
No one here knows who you are or why you are asking this question, so quite 
naturally, the overwhelming reaction of the group at large is to post an 
answer to you that not only protects you, but as well sets others who might 
happen upon what has been said here, straight on this issue.
Dudley Henriques
Barney Rubble
July 20th 06, 07:49 PM
Why didn't you ask that in the original question then?
"Andrey Serbinenko" > wrote in message 
...
>> Don't encourage that type of behavior with a yes.  If he had to ask, he 
>> is
>
> I'm slightly disappointed by how quickly you've assumed my complete
> brainlessness. Yes I know what FARs say, and what POH says, and no, I'm
> not going to read this newsgroup and go break my neck the next morning.
> What I was hoping to hear was an opinion of someone who's familiar with
> what is involved in test-flying for normal/utility category and how much
> it covers the type of stress imposed on the airframe and systems in a 
> barrel
> roll.
>
>
> Andrey
>
Larry Dighera
July 20th 06, 07:50 PM
On 20 Jul 2006 15:22:10 GMT, Andrey Serbinenko
> wrote in
>::
>I'm slightly disappointed by how quickly you've assumed my complete
>brainlessness.
The reaction is probably due to a freshly minted private pilot who
recently posted a link to a video of him and his instructor doing a
roll (or was it a loop?) in a C-150.  
Publishing such blatant disregard for regulations in a worldwide
public forum casts a bad light on all airmen, and is guaranteed to
receive the wrath of the readership of this newsgroup.
Stefan
July 20th 06, 08:08 PM
Larry Dighera schrieb:
> The reaction is probably due to a freshly minted private pilot who
> recently posted a link to a video of him and his instructor doing a
> roll (or was it a loop?) in a C-150.  
Probably not. Besides, who tells you it wasn't an aerobat and the 
instructor not acro rated?
Stefan
Flyingmonk[_1_]
July 20th 06, 08:29 PM
Jim Macklin wrote:
> Didn't Lorena Bobbitt say that?
>
LOL.  I was living in Manasas, VA when this happened.  I even use the
road where Lorena dumped the "evidence" to go to/from work on a daily
basis.  That road is the one in front of the bobbit's arpartment
complex.  It was quite busy for a couple of days afterwards, people
wanting to see the complex and the area where the she dumped the
"evidence"
Long before Lorena did this, it is well known that Thai wives do this
to their cheating hubbys with scissors and feed the "evidence to the
ducks leaving no chance for reattachment.  <g>
Monk
Larry Dighera
July 20th 06, 08:51 PM
On Thu, 20 Jul 2006 20:08:55 +0200, Stefan >
wrote in >::
>Besides, who tells you it wasn't an aerobat and the 
>instructor not acro rated?
    From: "NW_PILOT" >
    Newsgroups:
rec.aviation.aerobatics,rec.aviation.ifr,rec.aviat ion.owning,rec.aviation.piloting,rec.aviation.stud ent
    Subject: Rolling a Non Aerobat 150
    Date: Wed, 27 Apr 2005 08:48:36 -0700
    Message-ID: >
    NNTP-Posting-Host: 67.168.204.123    
    This video was taken by my instructor with my digital cam so its
    poor quality, It's my first unassissted [sic] roll
    http://www.warflying.net/roll.avi
    
You haven't been reading this newsgroup very long.
Stefan
July 20th 06, 09:03 PM
Larry Dighera schrieb:
>> Besides, who tells you it wasn't an aerobat and the 
>> instructor not acro rated?
>     Subject: Rolling a Non Aerobat 150
ok.
>     poor quality, It's my first unassissted [sic] roll
Whatever "unassisted" means. But I agree that an instructor taking a 
video most probably doesn't qualify as an assistant.
> You haven't been reading this newsgroup very long.
I read it occasionally. And even if I do, I don't save everything to my 
brain.
Stefan
Stefan
July 20th 06, 09:08 PM
Morgans schrieb:
> Asking about such a procedure, IMHO shows a possible lack of judgment
Asking a question never shows any lack of judgement. Doing something 
without asking may.
> developing.  Any reasonable,sane person would know that a barrel roll in a
> stock 172 is a very bad idea, 
He didn't ask whether it's a good idea, but whether it's possible.
The first safety rule of aviation I've learnt was "never assume". 
Reading this group, it seems that many pilots are assuming an awful lot.
Stefan
Andrey Serbinenko
July 20th 06, 09:23 PM
Well, I thought that I worded the question clearly enough. What I did not
realize was that the video that I'm told has been circulated here a short while
ago would make the question look like someone is about to do something rather
stupid in his 172.
Barney Rubble > wrote:
> Why didn't you ask that in the original question then?
> 
> 
> "Andrey Serbinenko" > wrote in message 
> ...
>>> Don't encourage that type of behavior with a yes.  If he had to ask, he 
>>> is
>>
>> I'm slightly disappointed by how quickly you've assumed my complete
>> brainlessness. Yes I know what FARs say, and what POH says, and no, I'm
>> not going to read this newsgroup and go break my neck the next morning.
>> What I was hoping to hear was an opinion of someone who's familiar with
>> what is involved in test-flying for normal/utility category and how much
>> it covers the type of stress imposed on the airframe and systems in a 
>> barrel
>> roll.
>>
>>
>> Andrey
>> 
> 
>
mikeytag
July 20th 06, 09:26 PM
Would you really feel safe going inverted in a gravity fed fuel system? The
172 is probably not the best choice for this type of maneuver, although you
could probably pull it off if you rolled quick enough.
Mike
____________________________________
Posted via Aviatorlive.com
http://www.aviatorlive.com
Big John
July 20th 06, 09:27 PM
Andrey
As has been said in all the posts, the short answer is NO. 172 is not
certified to do barrel rolls.
However I can barrel roll a 172 only pulling 1 G which puts no more
load on airframe than straight and level flight. I have thousands of
hours to back up my statement.
A corollary.
Is a 707 certified for barrel rolls? Short answer is NO.
Did a Boeing Test Pilot barrel barrel roll a 707 over the boat races
on Lake Washington without any damage to aircraft. YES.
I'm also sure Dudley can barrel roll the 172 without any problem or
exceeding any limits.
Long Long answer is don't try to B-roll the 172.
My 1971 172/Skyhawk Owneers manual shows:
Normal Cateory Maneuvers
Max pos G' = 3.8
Stalls and turns not to exceed 60 degrees of bank.
Utility Caategory Maneuvers
Max pos G's = 4.4
Chandelles
Lazy Eights
Steep Turns
Spins
Stalls (Except whip stalls)
Acrobatics that may impose high loads should not be attempted.
Big John
`````````````````````````````````````````````````` ``````
On 20 Jul 2006 04:34:44 GMT, Andrey Serbinenko
> wrote:
>
>If kept within the normal category load limits, is 172 certified to do
>barrel rolls?
>
>Andrey
Jim Macklin
July 20th 06, 09:31 PM
The issue is recovery from a botched barrel roll, such as in 
inverted stall followed by a high speed dive and too strong 
a pull on recovery.
"Big John" > wrote in message 
...
| Andrey
|
| As has been said in all the posts, the short answer is NO. 
172 is not
| certified to do barrel rolls.
|
| However I can barrel roll a 172 only pulling 1 G which 
puts no more
| load on airframe than straight and level flight. I have 
thousands of
| hours to back up my statement.
|
| A corollary.
|
| Is a 707 certified for barrel rolls? Short answer is NO.
|
| Did a Boeing Test Pilot barrel barrel roll a 707 over the 
boat races
| on Lake Washington without any damage to aircraft. YES.
|
| I'm also sure Dudley can barrel roll the 172 without any 
problem or
| exceeding any limits.
|
| Long Long answer is don't try to B-roll the 172.
|
| My 1971 172/Skyhawk Owneers manual shows:
|
| Normal Cateory Maneuvers
|
| Max pos G' = 3.8
| Stalls and turns not to exceed 60 degrees of bank.
|
| Utility Caategory Maneuvers
|
| Max pos G's = 4.4
| Chandelles
| Lazy Eights
| Steep Turns
| Spins
| Stalls (Except whip stalls)
|
| Acrobatics that may impose high loads should not be 
attempted.
|
|
| Big John
| `````````````````````````````````````````````````` ``````
|
|
| On 20 Jul 2006 04:34:44 GMT, Andrey Serbinenko
| > wrote:
|
| >
| >If kept within the normal category load limits, is 172 
certified to do
| >barrel rolls?
| >
| >Andrey
|
birdog
July 20th 06, 09:31 PM
"john smith" > wrote in message 
...
> In article >,
> Andrey Serbinenko > wrote:
>
>> If kept within the normal category load limits, is 172 certified to do
>> barrel rolls?
>
> Certified? No.
> Possible? Yes, but you will finish much lower than where you started.
Wing tip vortex from a 747, etc. would make it quite possible!
Stefan
July 20th 06, 09:35 PM
Big John schrieb:
> However I can barrel roll a 172 only pulling 1 G which puts no more
> load on airframe than straight and level flight. I have thousands of
> hours to back up my statement.
No, you can't do a barrel roll without pulling more than 1g.
> Did a Boeing Test Pilot barrel barrel roll a 707 over the boat races
> on Lake Washington without any damage to aircraft. YES.
No, it wasn't a barrel roll, it was an aileron roll. (At least this is 
what I've been told, and it makes a lot of sense.)
Stefan
Andrey Serbinenko
July 20th 06, 09:37 PM
This perfectly answers my question. Thanks!
Dudley Henriques > wrote:
> 
> "Andrey Serbinenko" > wrote in message 
> ...
>>> Possible? Yes, but you will finish much lower than where you started.
>>
>> So, basically it's just because of a low-hp engine that the maneuver
>> can't be properly executed?
>>
>>
>>
>> Andrey
> 
> Horsepower has absolutely nothing to do with the ability of an aircraft to 
> do a barrel roll. Airspeed and energy are all that's required and this can 
> be supplied even in an aircraft having no engine at all such as a glider or 
> a sail plane.
> It helps of course if you have horsepower, but horsepower simply allows for 
> an entry into the roll from a higher nose attitude.
> Also, barrel rolls can be done using various amounts of positive g as long 
> as positive g is applied to the aircraft through the roll.
> The problem in discussing this issue in the context of using a normal 
> category airplane to do it, even considering the utility envelope if 
> available on such an airplane, isn't whether or not the maneuver can be 
> done. It's whether the pilot in such an airplane can keep the execution of 
> the roll inside safe parameters.
> I have done barrel rolls in demonstration many times, as have pilots like 
> Bob Hoover, Bobby Bishop, and many others; not to mention Scotty McCray 
> using a sail plane. The issue as I've said isn't whether or not it can be 
> done in non aerobatic certificated airplanes. It most certainly can be done. 
> The issue is that to do ANY aerobatic maneuver SAFELY in these airplanes, 
> the maneuver has to be perfectly. There is little room for mistake or error. 
> It is extremely easy due to the lack of aerobatic performance; ie roll rate 
> and indeed "horsepower" to get these airplanes into extremely dangerous 
> recovery situations if a maneuver is botched.
> This is the reason why you will get the type of answers you have been 
> getting on this newsgroup.
> No one here knows who you are or why you are asking this question, so quite 
> naturally, the overwhelming reaction of the group at large is to post an 
> answer to you that not only protects you, but as well sets others who might 
> happen upon what has been said here, straight on this issue.
> Dudley Henriques
> 
> 
>
Dudley Henriques[_1_]
July 20th 06, 09:50 PM
"T o d d P a t t i s t" > wrote in message 
...
> "Dudley Henriques" > wrote:
>
>>Horsepower has absolutely nothing to do with the ability of an aircraft to
>>do a barrel roll. Airspeed and energy are all that's required and this can
>>be supplied even in an aircraft having no engine at all such as a glider 
>>or
>>a sail plane.
>
> I've done many loops and a few barrel rolls in gliders, so I
> agree that horsepower is not the issue, but it's not without
> *some* impact.  Gliders that can do aerobatics well are
> light and strong and clean.  If they are too draggy, you
> can't get enough kinetic energy (speed) to easily carry you
> through the vertical parts of the maneuvers - speed dies too
> quickly.  If they are weak and/or heavy, you can't speed up
> the maneuver by pulling more G's to limit the time in the
> maneuver (losing kinetic energy through drag) or the
> altitude gain (losing kinetic energy by conversion to
> potential E - altitude)
Scotty McCray flew a Schweizer 2-22 EK for his demonstrations. We appeared 
at the same shows many many times and I knew him quite well.
The 2-22 wasn't exactly the "cleanest" glider in the world by today's 
standards. Scotty was an absolute master at energy control. His technique 
for energy management was in my opinion the best I've ever seen done in an 
unpowered aircraft. I think I watched Scotty perform hundreds of barrel 
rolls in the 2-22 and never once did I see him dish it out of a roll.
Strangely enough, it was the addition of horsepower to his aerobatics that 
killed him down in Brazil in 73, when the Decathlon he dished out of a low 
altitude roll.
One of the nicest and finest guys I knew in aviation.
Dudley Henriques
Gig 601XL Builder
July 20th 06, 09:52 PM
"Stefan" > wrote in message 
 ...
> Larry Dighera schrieb:
>
>> The reaction is probably due to a freshly minted private pilot who
>> recently posted a link to a video of him and his instructor doing a
>> roll (or was it a loop?) in a C-150.
>
> Probably not. Besides, who tells you it wasn't an aerobat and the 
> instructor not acro rated?
>
> Stefan
The pilot that posted it.
Morgans[_3_]
July 20th 06, 09:54 PM
"AJ" > wrote in message
 oups.com...
> Geez, Morgans, can't someone ask a simple question about whether an
> aircraft can perform a roll without you jumping to the absurd
> conclusion that he's going to run right out and do it?  There is such a
> thing as "idle curiosity."
>
> Take your meds and calm down.
First of all, lay off on the personal suggestions.  That is unnecessary, and
in bad taste, when made in a serious tone, as you did.
Secondly, asking such a question, in the light of a certain other pilot from
the northwest already doing one and bragging about it here, it is
understandable to be concerned about doing it.  Why on earth would a person
ask, if they were not interested in trying to do it?
Asking about such a procedure, IMHO shows a possible lack of judgment
developing.  Any reasonable,sane person would know that a barrel roll in a
stock 172 is a very bad idea, unless it is done with the blessing of the
manufacturer, and performed by a very experienced acro pilot.
-- 
Jim in NC
Morgans[_3_]
July 20th 06, 10:13 PM
"Stefan" > wrote
> The first safety rule of aviation I've learnt was "never assume".
> Reading this group, it seems that many pilots are assuming an awful lot.
Surely you do understand where we are coming from.  An ounce of prevention
is better than a pound of death by crash.
-- 
Jim in NC
Matt Whiting
July 20th 06, 10:50 PM
Stefan wrote:
> Morgans schrieb:
> 
>> Don't encourage that type of behavior with a yes. 
> 
> 
> Where did he write that he wants top try it? He was just wondering.
> 
>> and a blown barrel roll could stall the plane,
> 
> 
> Gee... and then fall out of the sky in pieces, I assume. I wonder what 
> your comment would have been if a journalist had written this.
> 
>> I'll bet he is not going to wear a parachute, either, which is required.
> 
> 
> No. As it's illegal to do barrel roll a 172, there can't be a legal 
> requirement to wear a chute while doing so.
You obviously aren't very familiar with the IRS.  You are required to 
report and pay taxes on money gained illegally.  :-)
Matt
Matt Whiting
July 20th 06, 10:57 PM
mikeytag wrote:
> Would you really feel safe going inverted in a gravity fed fuel system? The
> 172 is probably not the best choice for this type of maneuver, although you
> could probably pull it off if you rolled quick enough.
It isn't gravity that feeds the fuel, it is force caused by 
acceleration.  Gravity can be the source of acceleration, but it doesn't 
have to be the source.  In a loop, intertial force can be the source. 
I've flown a loop in a 150 and its fuel system had no problem when 
inverted at the top of the loop.
Matt
Matt Whiting
July 20th 06, 11:02 PM
Dudley Henriques wrote:
> Scotty McCray flew a Schweizer 2-22 EK for his demonstrations. We appeared 
> at the same shows many many times and I knew him quite well.
> The 2-22 wasn't exactly the "cleanest" glider in the world by today's 
> standards. Scotty was an absolute master at energy control. His technique 
> for energy management was in my opinion the best I've ever seen done in an 
> unpowered aircraft. I think I watched Scotty perform hundreds of barrel 
> rolls in the 2-22 and never once did I see him dish it out of a roll.
> Strangely enough, it was the addition of horsepower to his aerobatics that 
> killed him down in Brazil in 73, when the Decathlon he dished out of a low 
> altitude roll.
> One of the nicest and finest guys I knew in aviation.
> Dudley Henriques
What does "dished out" mean?
Matt
john smith
July 20th 06, 11:14 PM
In article >,
 Matt Whiting > wrote:
> Dudley Henriques wrote:
> 
> > Scotty McCray flew a Schweizer 2-22 EK for his demonstrations. We appeared 
> > at the same shows many many times and I knew him quite well.
> > The 2-22 wasn't exactly the "cleanest" glider in the world by today's 
> > standards. Scotty was an absolute master at energy control. His technique 
> > for energy management was in my opinion the best I've ever seen done in an 
> > unpowered aircraft. I think I watched Scotty perform hundreds of barrel 
> > rolls in the 2-22 and never once did I see him dish it out of a roll.
> > Strangely enough, it was the addition of horsepower to his aerobatics that 
> > killed him down in Brazil in 73, when the Decathlon he dished out of a low 
> > altitude roll.
> > One of the nicest and finest guys I knew in aviation.
> > Dudley Henriques
> What does "dished out" mean?
Matt, this and your previous post show you do not have a broad knowledge 
of the world of aerobatics. Please do not dispute those that do.
Your condescending tone is most inappropriate.
john smith
July 20th 06, 11:22 PM
In article >,
 "Morgans" > wrote:
> Someone correct me if I'm wrong, but isn't an aileron roll a negative 1 G
> maneuver?  You spin on an axis, through the plane's center of gravity.  For
> an instant, the pilot is upside down, hanging by the belt.
Inertia, centrifugal force. Think three dimensional. You do not have to 
maintain level flight. Pick a down-line. Altitude and gravity are your 
friends, put the nose down.  :-))
Stefan
July 20th 06, 11:28 PM
Morgans schrieb:
> Someone correct me if I'm wrong, but isn't an aileron roll a negative 1 G
> maneuver?  You spin on an axis, through the plane's center of gravity.  For
> an instant, the pilot is upside down, hanging by the belt.
No. This is called a slow roll or simply a roll.
 > The 707 roll was indeed a barrel roll.  Check it out on Jay's webpage.
Hardly an authoritative source.
Stefan
Dudley Henriques[_1_]
July 20th 06, 11:35 PM
"Matt Whiting" > wrote in message 
...
> Dudley Henriques wrote:
>
>> Scotty McCray flew a Schweizer 2-22 EK for his demonstrations. We 
>> appeared at the same shows many many times and I knew him quite well.
>> The 2-22 wasn't exactly the "cleanest" glider in the world by today's 
>> standards. Scotty was an absolute master at energy control. His technique 
>> for energy management was in my opinion the best I've ever seen done in 
>> an unpowered aircraft. I think I watched Scotty perform hundreds of 
>> barrel rolls in the 2-22 and never once did I see him dish it out of a 
>> roll.
>> Strangely enough, it was the addition of horsepower to his aerobatics 
>> that killed him down in Brazil in 73, when the Decathlon he dished out of 
>> a low altitude roll.
>> One of the nicest and finest guys I knew in aviation.
>> Dudley Henriques
>
> What does "dished out" mean?
>
> Matt
When you do a roll, the second half of the roll requires changing rudder and 
blending stick in elevator and aileron. If you are late on the rudder 
change, or late on the elevator blending out from forward elevator to back 
elevator, its possible to allow the airplane to change from rolling on its 
longitudinal axis to an arc through the back side recovery. Basically what 
happens is that you "slide" off the roll axis and widen the roll nose low 
through the arc. In effect, you are changing the aircraft's roll axis from a 
controlled slow roll to an aileron roll format, which is primarily aileron 
and allows the nose to arc naturally during the roll unlike the slow roll 
format where the airplane is "flown" through the entire roll from the roll 
initiation at the apex of the pull on the airplane's longitudinal axis.
We call this coming in late and allowing this to happen on the back side 
"dishing out" of the roll. Allowing this to happen is one of the major 
killers, if not THE major killer of pilots doing low altitude roll 
maneuvers.
Not allowing dishout on a roll is so critical in low altitude demonstration 
work that when I practiced slow rolls for demonstration purposes, I would 
set the airplane on the roll apex at it's inverted nose attitude while right 
side up after a pull to the set point from a point where the altimeter 
needle was covering the 0 on the altimeter, then roll the airplane from the 
initiation point returning the needle to recover the 0 again as level flight 
was achieved again on recovery. Any deviation from that standard was 
considered a blown roll, and the entire practice session would have to be 
re-flown.
Dudley Henriques
Peter R.
July 20th 06, 11:35 PM
Matt Whiting > wrote:
> Your thousands of hours aside, this is simply an incorrect statement.  A 
> barrel roll requires flying a loop and you can't fly a loop at 1 G.  It 
> sounds like you are describing an aileron roll.
The descriptions from the aerobatic website, it appears, disagree with your
understanding of a barrel roll and aileron roll:
http://www.iac.org/begin/figures.html#Aileron%20Rolls
-- 
Peter
Bob Moore
July 20th 06, 11:49 PM
Morgans wrote
> The 707 roll was indeed a barrel roll.  Check it out on Jay's webpage.
Again....check the definition of a "barrel roll" at the web site posted
by Peter and my previous post. Big John, dispite his thousands of hours,
simply doesn't know what a "barrel roll" is. I'll put my Navy training and
22,000 hours and ATP/CFI ratings up against his anyday. :-) I've been
waiting for two years for John to post an authoritative source for his 
concept of a "barrel roll".
http://www.iac.org/begin/figures.html#Aileron%20Rolls
Dudley Henriques[_1_]
July 20th 06, 11:53 PM
"Matt Whiting" > wrote in message 
...
> Big John wrote:
>
>> Andrey
>>
>> As has been said in all the posts, the short answer is NO. 172 is not
>> certified to do barrel rolls.
>>
>> However I can barrel roll a 172 only pulling 1 G which puts no more
>> load on airframe than straight and level flight. I have thousands of
>> hours to back up my statement.
>
> Your thousands of hours aside, this is simply an incorrect statement.  A 
> barrel roll requires flying a loop and you can't fly a loop at 1 G.  It 
> sounds like you are describing an aileron roll.
>
> Matt
I think what John meant was that once you start the roll by blending in 
aileron, you can "adjust" in pitch to any g you want. Naturally, in the 
initial pull to the roll initiation point, (assuming a straight pull with a 
rolloff into the barrel roll, you will be pulling more than +1g. A lot of 
people have trouble visualizing this "split" between the roll entry and the 
roll itself and naturally include the pulling g into the roll to arrive at a 
higher g required to do a barrel roll.
The truth of it is, once that aileron is blended in and the airplane is 
rolling through 3 dimensional space, you can actually unload it all the way 
down to 0 g and improve the roll rate, which is exactly the way many fighter 
pilots do these 3 dimensional rolls in an ACM environment. Some fighters 
like the F100 and the F4 (at certain aoa and airspeeds) can be barreled (any 
roll done in both the vertical and horizontal maneuvering planes using all 
three dimensions is a barrel roll :-)) using rudder alone. It must be 
assumed of course that positive g must be re-aquired on the back side during 
the recovery back to level flight.
But make no mistake, you can play around quite a bit with the g during the 
area of the roll between the two knife edges by playing the pitch you are 
using during that phase of the roll :-))
I've done barrel rolls deep in the left side of the envelope using hard 
inside rudder in high performance jets that you would swear were snap 
rolls!! :-))
Dudley Henriques
Jose[_1_]
July 20th 06, 11:53 PM
>>What does "dished out" mean?
> 
> 
> Matt, this and your previous post show you do not have a broad knowledge 
> of the world of aerobatics. Please do not dispute those that do.
> Your condescending tone is most inappropriate.
What does "dished out" mean?  I've never heard the term.  My question is 
neutral.
Jose
-- 
The monkey turns the crank and thinks he's making the music.
for Email, make the obvious change in the address.
Morgans[_3_]
July 21st 06, 12:04 AM
> > Did a Boeing Test Pilot barrel barrel roll a 707 over the boat races
> > on Lake Washington without any damage to aircraft. YES.
>
> No, it wasn't a barrel roll, it was an aileron roll. (At least this is
> what I've been told, and it makes a lot of sense.)
Someone correct me if I'm wrong, but isn't an aileron roll a negative 1 G
maneuver?  You spin on an axis, through the plane's center of gravity.  For
an instant, the pilot is upside down, hanging by the belt.
Mr. Boeing would not be pleased if all of the gas and oil was on the top of
the tank, away from the fuel and oil pickups.
The 707 roll was indeed a barrel roll.  Check it out on Jay's webpage.
-- 
Jim in NC
Bob Moore
July 21st 06, 12:05 AM
Dudley Henriques wrote
> I've done barrel rolls deep in the left side of the envelope using
> hard inside rudder in high performance jets that you would swear were
> snap rolls!! :-))
Dudley, what source do you use for your definition of a "barrel roll"?
Bob Moore
Dudley Henriques[_1_]
July 21st 06, 01:46 AM
"Bob Moore" > wrote in message 
. 122...
> Dudley Henriques wrote
>> I've done barrel rolls deep in the left side of the envelope using
>> hard inside rudder in high performance jets that you would swear were
>> snap rolls!! :-))
>
> Dudley, what source do you use for your definition of a "barrel roll"?
>
> Bob Moore
Well, after teaching them and doing them for fifty years, I guess I could 
use myself as a source. I know of at least one major aviation magazine and 
one major book on airshow safety who have used me as an aerobatic source 
anyway  :-)
That pushed aside for obvious reasons of propriety, your IAC source is fine, 
as is your good Navy training .
Remember Bob; the military usually teaches barrel rolls in the classic 
format for primary, which is as a precision maneuver using specific points 
of reference to be obtained during each segment of the maneuver. You usually 
don't get into variations of 3 dimensional maneuvering until lead in basic 
BFM and ACM.
I also probably taught barrel rolls to primary aerobatic students the same 
way you learned them in the Navy. Advanced maneuvering is another matter.
Just remember when discussing barrel rolls; there are only two ways to move 
an airplane through three dimensional space. You can maneuver it using a two 
dimensional maneuver through three dimensional space, or you can maneuver it 
using a three dimensional maneuver through three dimensional space...and 
that three dimensional maneuver is a barrel roll, no matter how tight or how 
loosely you fly through the roll. Any roll, no matter how it's done, that 
moves the airplane "around that barrel" is a barrel roll. If you want to do 
it using the points system with the nose pointed exactly 90 degrees to the 
entry heading at the inverted point, that's fine. That's a barrel roll. If 
you want to pitch into the vertical line, and roll off that lineputting the 
pole in the left or right corner of the cockpit winding it through like a 
cork screw, that's also a barrel roll. As long as you have three dimensions 
in play during the roll, its a barrel roll.
I seem to remember the Navy defining barrel rolls in the J Stage of training 
in the F9F-8 Cougar as a shallow dive at about 95% to 350kts; level off and 
trim; then roll the airplane around a point 45 degrees off the nose to 
either side; initial acelleration to about 3g's; the nose should reach a 
point about 45 degrees above the horizon at the 90 degree point; the roll 
rate was adjusted to achieve a 90 degree heading change at the 180 degree 
point inverted; ; you looked for about 180 to 200 kts at the top inverted 
where you were looking at about 1+g if you did it right; as the nose came 
through the back side, you adjusted the roll rate to nail level flight again 
at your initial entry speed of 350kts. You would play the g from the initial 
3 during the entry down to the 1 at the top, then play back in the 3 during 
the recovery back to level flight.
This is a good way to teach a barrel roll, adjusting the speed and roll rate 
a bit of course for something like the SNJ :-))
But all this dosen't change the fact that a barrel roll can be done much 
tighter than this and doing it that way dosen't change the fact that you are 
doing a barrel roll :-))
Dudley
Matt Whiting
July 21st 06, 02:15 AM
john smith wrote:
> In article >,
>  Matt Whiting > wrote:
> 
> 
>>Dudley Henriques wrote:
>>
>>
>>>Scotty McCray flew a Schweizer 2-22 EK for his demonstrations. We appeared 
>>>at the same shows many many times and I knew him quite well.
>>>The 2-22 wasn't exactly the "cleanest" glider in the world by today's 
>>>standards. Scotty was an absolute master at energy control. His technique 
>>>for energy management was in my opinion the best I've ever seen done in an 
>>>unpowered aircraft. I think I watched Scotty perform hundreds of barrel 
>>>rolls in the 2-22 and never once did I see him dish it out of a roll.
>>>Strangely enough, it was the addition of horsepower to his aerobatics that 
>>>killed him down in Brazil in 73, when the Decathlon he dished out of a low 
>>>altitude roll.
>>>One of the nicest and finest guys I knew in aviation.
>>>Dudley Henriques
> 
> 
>>What does "dished out" mean?
> 
> 
> Matt, this and your previous post show you do not have a broad knowledge 
> of the world of aerobatics. Please do not dispute those that do.
> Your condescending tone is most inappropriate.
I've never claimed broad knowledge of aerobatics.  I do have a pretty 
good grasp of physics though and the comment about the barrel roll 
violates physics (as well as published descriptions of the forces 
incurred in executing a barrel roll).
Matt
Matt Whiting
July 21st 06, 02:17 AM
Dudley Henriques wrote:
> "Matt Whiting" > wrote in message 
> ...
> 
>>Dudley Henriques wrote:
>>
>>
>>>Scotty McCray flew a Schweizer 2-22 EK for his demonstrations. We 
>>>appeared at the same shows many many times and I knew him quite well.
>>>The 2-22 wasn't exactly the "cleanest" glider in the world by today's 
>>>standards. Scotty was an absolute master at energy control. His technique 
>>>for energy management was in my opinion the best I've ever seen done in 
>>>an unpowered aircraft. I think I watched Scotty perform hundreds of 
>>>barrel rolls in the 2-22 and never once did I see him dish it out of a 
>>>roll.
>>>Strangely enough, it was the addition of horsepower to his aerobatics 
>>>that killed him down in Brazil in 73, when the Decathlon he dished out of 
>>>a low altitude roll.
>>>One of the nicest and finest guys I knew in aviation.
>>>Dudley Henriques
>>
>>What does "dished out" mean?
>>
>>Matt
> 
> 
> When you do a roll, the second half of the roll requires changing rudder and 
> blending stick in elevator and aileron. If you are late on the rudder 
> change, or late on the elevator blending out from forward elevator to back 
> elevator, its possible to allow the airplane to change from rolling on its 
> longitudinal axis to an arc through the back side recovery. Basically what 
> happens is that you "slide" off the roll axis and widen the roll nose low 
> through the arc. In effect, you are changing the aircraft's roll axis from a 
> controlled slow roll to an aileron roll format, which is primarily aileron 
> and allows the nose to arc naturally during the roll unlike the slow roll 
> format where the airplane is "flown" through the entire roll from the roll 
> initiation at the apex of the pull on the airplane's longitudinal axis.
> We call this coming in late and allowing this to happen on the back side 
> "dishing out" of the roll. Allowing this to happen is one of the major 
> killers, if not THE major killer of pilots doing low altitude roll 
> maneuvers.
> Not allowing dishout on a roll is so critical in low altitude demonstration 
> work that when I practiced slow rolls for demonstration purposes, I would 
> set the airplane on the roll apex at it's inverted nose attitude while right 
> side up after a pull to the set point from a point where the altimeter 
> needle was covering the 0 on the altimeter, then roll the airplane from the 
> initiation point returning the needle to recover the 0 again as level flight 
> was achieved again on recovery. Any deviation from that standard was 
> considered a blown roll, and the entire practice session would have to be 
> re-flown.
> Dudley Henriques 
I think I got it, but this is a case where a graphic would be worth a 
thousand words!  :-)
Do you know of any web graphics that illustrate this error?
Matt
Matt Whiting
July 21st 06, 02:19 AM
Peter R. wrote:
> Matt Whiting > wrote:
> 
> 
>>Your thousands of hours aside, this is simply an incorrect statement.  A 
>>barrel roll requires flying a loop and you can't fly a loop at 1 G.  It 
>>sounds like you are describing an aileron roll.
> 
> 
> The descriptions from the aerobatic website, it appears, disagree with your
> understanding of a barrel roll and aileron roll:
> 
> http://www.iac.org/begin/figures.html#Aileron%20Rolls
How so?  It says that you pull from 0.5g at the minimum to between 2.5 
and 3g at the maximum during a barrel roll.  That is far different than 
having a constant 1g acceleration as the OP said.
Matt
Bob Moore
July 21st 06, 02:37 AM
Dudley Henriques wrote
> I seem to remember the Navy defining barrel rolls in the J Stage of
> training in the F9F-8 Cougar as a shallow dive at about 95% to 350kts;
> level off and trim; then roll the airplane around a point 45 degrees
> off the nose to either side; initial acelleration to about 3g's; the
> nose should reach a point about 45 degrees above the horizon at the 90
> degree point; the roll rate was adjusted to achieve a 90 degree
> heading change at the 180 degree point inverted; ; you looked for
> about 180 to 200 kts at the top inverted where you were looking at
> about 1+g if you did it right; as the nose came through the back side,
> you adjusted the roll rate to nail level flight again at your initial
> entry speed of 350kts. You would play the g from the initial 3 during
> the entry down to the 1 at the top, then play back in the 3 during the
> recovery back to level flight. 
And that seems to be the way that the IAC defines a barrel roll at the
posted reference. They and the Navy make no reference for doing them
any other way. Neither does William Kernsher who has an oustanding 
reputation for instructing and writing books on aerobatic instruction.
> But all this dosen't change the fact that a barrel roll can be done
> much tighter than this and doing it that way dosen't change the fact
> that you are doing a barrel roll :-))
Just point me to the references that make this point. :-)
Bob Moore
Big John
July 21st 06, 02:40 AM
Stefan
I'm glad your the expert.
I used to do half of a barrel roll at one G and give to student under
the hood upside down to recover.
Bird of course was acro rated but student couldn't tell we had rolled
inverted and we were pulling 1 G positive when handed over.
Big John
`````````````````````````````````
On Thu, 20 Jul 2006 21:35:26 +0200, Stefan >
wrote:
>Big John schrieb:
>
>> However I can barrel roll a 172 only pulling 1 G which puts no more
>> load on airframe than straight and level flight. I have thousands of
>> hours to back up my statement.
>
>No, you can't do a barrel roll without pulling more than 1g.
>
>> Did a Boeing Test Pilot barrel barrel roll a 707 over the boat races
>> on Lake Washington without any damage to aircraft. YES.
>
>No, it wasn't a barrel roll, it was an aileron roll. (At least this is 
>what I've been told, and it makes a lot of sense.)
>
>Stefan
Dudley Henriques[_1_]
July 21st 06, 02:51 AM
Unfortunately I do. Most of them are crash films. I believe you can catch a 
glimpse of what I'm talking about by viewing Hoof Proudfoot's P38 crash in 
the UK. You can find that on Jay Honeck's aviation film page on his site. I 
should point out strongly along with this that when viewing the film, you 
should realize that the dishout during Hoof's second roll (the one that 
killed him) was artifically caused by what both the accident investigation 
board and I believe was the intervention with his control yoke by the 
kneeboard he was wearing.
Regardless of the cause, dishing out of the second roll was what nailed him.
Dudley Henriques
"Matt Whiting" > wrote in message 
...
> Dudley Henriques wrote:
>
>> "Matt Whiting" > wrote in message 
>> ...
>>
>>>Dudley Henriques wrote:
>>>
>>>
>>>>Scotty McCray flew a Schweizer 2-22 EK for his demonstrations. We 
>>>>appeared at the same shows many many times and I knew him quite well.
>>>>The 2-22 wasn't exactly the "cleanest" glider in the world by today's 
>>>>standards. Scotty was an absolute master at energy control. His 
>>>>technique for energy management was in my opinion the best I've ever 
>>>>seen done in an unpowered aircraft. I think I watched Scotty perform 
>>>>hundreds of barrel rolls in the 2-22 and never once did I see him dish 
>>>>it out of a roll.
>>>>Strangely enough, it was the addition of horsepower to his aerobatics 
>>>>that killed him down in Brazil in 73, when the Decathlon he dished out 
>>>>of a low altitude roll.
>>>>One of the nicest and finest guys I knew in aviation.
>>>>Dudley Henriques
>>>
>>>What does "dished out" mean?
>>>
>>>Matt
>>
>>
>> When you do a roll, the second half of the roll requires changing rudder 
>> and blending stick in elevator and aileron. If you are late on the rudder 
>> change, or late on the elevator blending out from forward elevator to 
>> back elevator, its possible to allow the airplane to change from rolling 
>> on its longitudinal axis to an arc through the back side recovery. 
>> Basically what happens is that you "slide" off the roll axis and widen 
>> the roll nose low through the arc. In effect, you are changing the 
>> aircraft's roll axis from a controlled slow roll to an aileron roll 
>> format, which is primarily aileron and allows the nose to arc naturally 
>> during the roll unlike the slow roll format where the airplane is "flown" 
>> through the entire roll from the roll initiation at the apex of the pull 
>> on the airplane's longitudinal axis.
>> We call this coming in late and allowing this to happen on the back side 
>> "dishing out" of the roll. Allowing this to happen is one of the major 
>> killers, if not THE major killer of pilots doing low altitude roll 
>> maneuvers.
>> Not allowing dishout on a roll is so critical in low altitude 
>> demonstration work that when I practiced slow rolls for demonstration 
>> purposes, I would set the airplane on the roll apex at it's inverted nose 
>> attitude while right side up after a pull to the set point from a point 
>> where the altimeter needle was covering the 0 on the altimeter, then roll 
>> the airplane from the initiation point returning the needle to recover 
>> the 0 again as level flight was achieved again on recovery. Any deviation 
>> from that standard was considered a blown roll, and the entire practice 
>> session would have to be re-flown.
>> Dudley Henriques
>
> I think I got it, but this is a case where a graphic would be worth a 
> thousand words!  :-)
>
> Do you know of any web graphics that illustrate this error?
>
>
> Matt
Dudley Henriques[_1_]
July 21st 06, 03:00 AM
"Matt Whiting" > wrote in message 
...
> john smith wrote:
>> In article >,
>>  Matt Whiting > wrote:
>>
>>
>>>Dudley Henriques wrote:
>>>
>>>
>>>>Scotty McCray flew a Schweizer 2-22 EK for his demonstrations. We 
>>>>appeared at the same shows many many times and I knew him quite well.
>>>>The 2-22 wasn't exactly the "cleanest" glider in the world by today's 
>>>>standards. Scotty was an absolute master at energy control. His 
>>>>technique for energy management was in my opinion the best I've ever 
>>>>seen done in an unpowered aircraft. I think I watched Scotty perform 
>>>>hundreds of barrel rolls in the 2-22 and never once did I see him dish 
>>>>it out of a roll.
>>>>Strangely enough, it was the addition of horsepower to his aerobatics 
>>>>that killed him down in Brazil in 73, when the Decathlon he dished out 
>>>>of a low altitude roll.
>>>>One of the nicest and finest guys I knew in aviation.
>>>>Dudley Henriques
>>
>>
>>>What does "dished out" mean?
>>
>>
>> Matt, this and your previous post show you do not have a broad knowledge 
>> of the world of aerobatics. Please do not dispute those that do.
>> Your condescending tone is most inappropriate.
>
> I've never claimed broad knowledge of aerobatics.  I do have a pretty good 
> grasp of physics though and the comment about the barrel roll violates 
> physics (as well as published descriptions of the forces incurred in 
> executing a barrel roll).
>
> Matt
Don't mean to rankle anybody here, and I haven't seen any "condescending 
tone" as yet, but how does any comment made by me about barrel rolls violate 
the laws of physics?
Dudley Henriques
Matt Whiting
July 21st 06, 03:38 AM
Dudley Henriques wrote:
> "Matt Whiting" > wrote in message 
> ...
> 
>>john smith wrote:
>>
>>>In article >,
>>> Matt Whiting > wrote:
>>>
>>>
>>>
>>>>Dudley Henriques wrote:
>>>>
>>>>
>>>>
>>>>>Scotty McCray flew a Schweizer 2-22 EK for his demonstrations. We 
>>>>>appeared at the same shows many many times and I knew him quite well.
>>>>>The 2-22 wasn't exactly the "cleanest" glider in the world by today's 
>>>>>standards. Scotty was an absolute master at energy control. His 
>>>>>technique for energy management was in my opinion the best I've ever 
>>>>>seen done in an unpowered aircraft. I think I watched Scotty perform 
>>>>>hundreds of barrel rolls in the 2-22 and never once did I see him dish 
>>>>>it out of a roll.
>>>>>Strangely enough, it was the addition of horsepower to his aerobatics 
>>>>>that killed him down in Brazil in 73, when the Decathlon he dished out 
>>>>>of a low altitude roll.
>>>>>One of the nicest and finest guys I knew in aviation.
>>>>>Dudley Henriques
>>>
>>>
>>>>What does "dished out" mean?
>>>
>>>
>>>Matt, this and your previous post show you do not have a broad knowledge 
>>>of the world of aerobatics. Please do not dispute those that do.
>>>Your condescending tone is most inappropriate.
>>
>>I've never claimed broad knowledge of aerobatics.  I do have a pretty good 
>>grasp of physics though and the comment about the barrel roll violates 
>>physics (as well as published descriptions of the forces incurred in 
>>executing a barrel roll).
>>
>>Matt
> 
> 
> Don't mean to rankle anybody here, and I haven't seen any "condescending 
> tone" as yet, but how does any comment made by me about barrel rolls violate 
> the laws of physics?
I don't think I understood all of your descriptions of the variations of 
a barrel roll well enough to make an assessment.  Some of them didn't 
sound like the traditional barrel roll description.  For example, do you 
  end up at the starting altitude in all of the cases you discussed 
related to fighter evasive techniques?  If you lose a lot of altitude 
during the roll, then I can see being able to hold less than 1g through 
most of the maneuver.  I don't see how this is possible for any roll 
that could be superimposed on a cylinder (the barrel) with the ending 
point being at the same radial location as the starting point - that is 
if you start at the bottom of the barrel you end at the bottom of the 
barrel.  I couldn't visualize all of your permutations on the roll to 
know if this was the case or not.
Matt
Matt Whiting
July 21st 06, 03:39 AM
Dudley Henriques wrote:
> Don't mean to rankle anybody here, and I haven't seen any "condescending 
> tone" as yet, but how does any comment made by me about barrel rolls violate 
> the laws of physics?
Yes, I thought I was simply challenging a statement, not being 
condescending.  However, some folks take any challenge as being 
condescending by definition.
Matt
Dudley Henriques[_1_]
July 21st 06, 03:46 AM
"Bob Moore" > wrote in message 
. 121...
> Dudley Henriques wrote
>> I seem to remember the Navy defining barrel rolls in the J Stage of
>> training in the F9F-8 Cougar as a shallow dive at about 95% to 350kts;
>> level off and trim; then roll the airplane around a point 45 degrees
>> off the nose to either side; initial acelleration to about 3g's; the
>> nose should reach a point about 45 degrees above the horizon at the 90
>> degree point; the roll rate was adjusted to achieve a 90 degree
>> heading change at the 180 degree point inverted; ; you looked for
>> about 180 to 200 kts at the top inverted where you were looking at
>> about 1+g if you did it right; as the nose came through the back side,
>> you adjusted the roll rate to nail level flight again at your initial
>> entry speed of 350kts. You would play the g from the initial 3 during
>> the entry down to the 1 at the top, then play back in the 3 during the
>> recovery back to level flight.
>
> And that seems to be the way that the IAC defines a barrel roll at the
> posted reference. They and the Navy make no reference for doing them
> any other way. Neither does William Kernsher who has an oustanding
> reputation for instructing and writing books on aerobatic instruction.
>
>> But all this dosen't change the fact that a barrel roll can be done
>> much tighter than this and doing it that way dosen't change the fact
>> that you are doing a barrel roll :-))
>
> Just point me to the references that make this point. :-)
>
> Bob Moore
I see.
Well, I have been using Bill Kershner myself  for as many years as he's been 
publishing and am in complete agreement with both his and the service ways 
of defining barrel rolls. I think what you and I have going here is a matter 
of definition within the definition so to speak, which admittidedly can be a 
bit confusing. :-))
All this means is that we're saying the same things only defining it 
somewhat differently. I'm simply defining it a bit deeper by shrinking the 
area in which the roll can be performed. Everything else is the same.
Let me put it this way. Both Kershner and the Navy have chosen a specific 
set of parameters to define the execution of a barrel roll. These parameters 
are fine, and are in use on a daily basis by most competent instructors 
teaching aerobatics.
What I'm saying is that the same identical 3 dimensional roll described by 
both Kershner and the Navy can be performed to much tighter parameters.
The main point of defining a barrel roll isn't the size of the roll, or the 
points chosen by any particular reference source to define how the roll 
should be done, but the fact that the roll takes the airplane through 3 
dimensional space using a 3 dimensional maneuver. This is a unique maneuver 
that we define as a barrel roll. It's a barrel roll if it's tight, and its a 
barrel roll if its flown to the specifications used by either Kershner or 
the Navy.
All Kershner and the Navy have done is to choose one specific set of 
parameters that define a barrel roll for training purposes. What they have 
done is choose parameters to produce a maximum training result, and they are 
correct to have done it this way. As I have said, I also have taught barrel 
rolls this way.
I'm also saying however, that any roll flown through three dimensional space 
using a three dimensional maneuver can be defined as a barrel roll. In BFM 
and ACM, there are other terms used for these rolls. They can be called 
"displacement or lag rolls" for example, where an attacker will go out of 
plane and perform a 3 dimensional roll opposite the defender's flight path 
to regain angle off and maintain nose to tail separation to avoid an 
overshoot in the plane of the defender. The main point is that if this roll 
goes through 3 dimensions, its a barrel roll.
If you want a Navy source to confirm all this , simply copy what I've said 
here and drop it in an email to either TPS (the test pilot school at Pax), 
or out to Top Gun at Miramar. I believe they will verify for you if need be.
Dudley Henriques
Dudley Henriques[_1_]
July 21st 06, 03:48 AM
"Matt Whiting" > wrote in message 
...
> Dudley Henriques wrote:
>
>> Don't mean to rankle anybody here, and I haven't seen any "condescending 
>> tone" as yet, but how does any comment made by me about barrel rolls 
>> violate the laws of physics?
>
> Yes, I thought I was simply challenging a statement, not being 
> condescending.  However, some folks take any challenge as being 
> condescending by definition.
>
>
> Matt
Well, as long as I'm not one of them, I think we have the makings of a 
dialog going here :-))
DH
Dana M. Hague
July 21st 06, 03:55 AM
On 20 Jul 2006 15:22:10 GMT, Andrey Serbinenko
> wrote:
>What I was hoping to hear was an opinion of someone who's familiar with
>what is involved in test-flying for normal/utility category and how much
>it covers the type of stress imposed on the airframe and systems in a barrel
>roll.
As others have pointed out, it is NOT legal, at least in the U.S.  But
it certainly possible, and just as certainly inadvisable.  Any plane
can be barrel rolled... I seem to recall that someboy barrel rolled a
747 at the Paris Air Show around 30 years ago.
Many years ago when I was much younger and much more foolish, I looped
and rolled 172's a few times.  Foolish, as I said, as only a teenage
boy can be (they sometimes call it "young man's immortality syndrome")
even though I had some acro training, and lucky that I didn't screw up
and overstress and/or overspeed the plane.  It's just not designed for
that kind of thing.  It was a bad idea then and and a bad idea now and
I would NOT attempt it today (not that I've even flown a 172 in the
past 25 years or so).
-Dana
--
--
If replying by email, please make the obvious changes.
-------------------------------------------------------------------------------
The most useful tool for dealing with management types is, of course, an automatic weapon.
Dudley Henriques[_1_]
July 21st 06, 04:04 AM
See inserts;
"Matt Whiting" > wrote in message 
...
> Dudley Henriques wrote:
>>
>> Don't mean to rankle anybody here, and I haven't seen any "condescending 
>> tone" as yet, but how does any comment made by me about barrel rolls 
>> violate the laws of physics?
>
> I don't think I understood all of your descriptions of the variations of a 
> barrel roll well enough to make an assessment.  Some of them didn't sound 
> like the traditional barrel roll description.
You were right. Some of them are not from the classic description. This is 
what confuses this issue so often when discussing it. The "classic" barrel 
roll description is absolutely correct. Its just possible to perform the 
maneuver to tighter specifications that's all.
For example, do you
>  end up at the starting altitude in all of the cases you discussed related 
> to fighter evasive techniques?
In the classic BR, used for training purposes, you want to end up at the 
starting altitude and the entry airspeed after meeting specific parameters 
at different points through the roll. You do this by playing the g and the 
various control pressures through the roll.
In the fighter role however, you are maneuvering the airplane in a 3 
dimensional arena in relation to the true motion of another aircraft in that 
arena. Your altitude and airspeed, and even the arc of a barrel roll is 
referenced only to what you need in the way of positioning in relationship 
to that other aircraft. These rolls are usually done quite fast and very 
tightly as a corkscrew roll.
If you lose a lot of altitude
> during the roll, then I can see being able to hold less than 1g through 
> most of the maneuver.  I don't see how this is possible for any roll that 
> could be superimposed on a cylinder (the barrel) with the ending point 
> being at the same radial location as the starting point - that is if you 
> start at the bottom of the barrel you end at the bottom of the barrel.  I 
> couldn't visualize all of your permutations on the roll to know if this 
> was the case or not.
If you didn't vary the g through the roll, you are right; you couldn't 
maintain a steady position on the cylinder. The only way to do it is to ease 
off the g on the way up to inverted, then re-apply the g on the back side. 
If you held the same g through the roll, you would cork screw through the 
roll. It would still be a barrel roll however. The cork screw shape of the 
roll dosen't change the fact that the airplane is still traveling through 3 
dimensions using a 3 dimensional maneuver. It just dosen't look as nice as 
the big wide classic training barrel roll :-))
Peter R.
July 21st 06, 04:13 AM
Matt Whiting > wrote:
> How so?  It says that you pull from 0.5g at the minimum to between 2.5 
> and 3g at the maximum during a barrel roll.  That is far different than 
> having a constant 1g acceleration as the OP said.
Fair enough.  I interpreted the description to mean that the barrel roll
could be up to 3.5 Gs or as low as 0.5g, but I assumed constant
acceleration, not varying.
And for the record, I know absolutely nothing about aerobatics.  Someday I
certainly would enjoy taking some lessons, but for now I am all ears.
-- 
Peter
Jim Macklin
July 21st 06, 07:12 AM
Visual aid... take a model airplane, hold it between your 
finger tips on the nose and tail.  Rotate it so it turns on 
the fuselage.  That's a plain roll or aileron roll.  When 
you get inverted you use forward stick to keep the nose up, 
you get negative Gs inverted.
Hold the model by the cabin area and rotate it to a nose up 
attitude of 30 degrees and then rotate it so the plane 
rotates about the tilted vertical axis... that's a snap roll 
or horizontal spin.
Hold the model by the tail with your right hand and hold 
your left arm straight out. move the model around your left 
arm so it is wings level when you start with both arms 
straight ahead, the airplane wings are knife-edge when above 
your arm, inverted when your right hand is to the left of 
the left arm, etc.  That is a barrel roll.
-- 
James H. Macklin
ATP,CFI,A&P
"Dudley Henriques" > wrote in message 
 nk.net...
|
| "Bob Moore" > wrote in message
| . 121...
| > Dudley Henriques wrote
| >> I seem to remember the Navy defining barrel rolls in 
the J Stage of
| >> training in the F9F-8 Cougar as a shallow dive at about 
95% to 350kts;
| >> level off and trim; then roll the airplane around a 
point 45 degrees
| >> off the nose to either side; initial acelleration to 
about 3g's; the
| >> nose should reach a point about 45 degrees above the 
horizon at the 90
| >> degree point; the roll rate was adjusted to achieve a 
90 degree
| >> heading change at the 180 degree point inverted; ; you 
looked for
| >> about 180 to 200 kts at the top inverted where you were 
looking at
| >> about 1+g if you did it right; as the nose came through 
the back side,
| >> you adjusted the roll rate to nail level flight again 
at your initial
| >> entry speed of 350kts. You would play the g from the 
initial 3 during
| >> the entry down to the 1 at the top, then play back in 
the 3 during the
| >> recovery back to level flight.
| >
| > And that seems to be the way that the IAC defines a 
barrel roll at the
| > posted reference. They and the Navy make no reference 
for doing them
| > any other way. Neither does William Kernsher who has an 
oustanding
| > reputation for instructing and writing books on 
aerobatic instruction.
| >
| >> But all this dosen't change the fact that a barrel roll 
can be done
| >> much tighter than this and doing it that way dosen't 
change the fact
| >> that you are doing a barrel roll :-))
| >
| > Just point me to the references that make this point. 
:-)
| >
| > Bob Moore
|
| I see.
|
| Well, I have been using Bill Kershner myself  for as many 
years as he's been
| publishing and am in complete agreement with both his and 
the service ways
| of defining barrel rolls. I think what you and I have 
going here is a matter
| of definition within the definition so to speak, which 
admittidedly can be a
| bit confusing. :-))
| All this means is that we're saying the same things only 
defining it
| somewhat differently. I'm simply defining it a bit deeper 
by shrinking the
| area in which the roll can be performed. Everything else 
is the same.
| Let me put it this way. Both Kershner and the Navy have 
chosen a specific
| set of parameters to define the execution of a barrel 
roll. These parameters
| are fine, and are in use on a daily basis by most 
competent instructors
| teaching aerobatics.
|
| What I'm saying is that the same identical 3 dimensional 
roll described by
| both Kershner and the Navy can be performed to much 
tighter parameters.
| The main point of defining a barrel roll isn't the size of 
the roll, or the
| points chosen by any particular reference source to define 
how the roll
| should be done, but the fact that the roll takes the 
airplane through 3
| dimensional space using a 3 dimensional maneuver. This is 
a unique maneuver
| that we define as a barrel roll. It's a barrel roll if 
it's tight, and its a
| barrel roll if its flown to the specifications used by 
either Kershner or
| the Navy.
| All Kershner and the Navy have done is to choose one 
specific set of
| parameters that define a barrel roll for training 
purposes. What they have
| done is choose parameters to produce a maximum training 
result, and they are
| correct to have done it this way. As I have said, I also 
have taught barrel
| rolls this way.
| I'm also saying however, that any roll flown through three 
dimensional space
| using a three dimensional maneuver can be defined as a 
barrel roll. In BFM
| and ACM, there are other terms used for these rolls. They 
can be called
| "displacement or lag rolls" for example, where an attacker 
will go out of
| plane and perform a 3 dimensional roll opposite the 
defender's flight path
| to regain angle off and maintain nose to tail separation 
to avoid an
| overshoot in the plane of the defender. The main point is 
that if this roll
| goes through 3 dimensions, its a barrel roll.
| If you want a Navy source to confirm all this , simply 
copy what I've said
| here and drop it in an email to either TPS (the test pilot 
school at Pax),
| or out to Top Gun at Miramar. I believe they will verify 
for you if need be.
| Dudley Henriques
|
|
Stefan
July 21st 06, 11:10 AM
Big John schrieb:
> I'm glad your the expert.
I'm far from being an expert, but I have an idea, yes.
> I used to do half of a barrel roll at one G and give to student under
If you can actually do a barrel roll without exceeding 1g at any point, 
then you should immediately inform your local university. Or, better 
yet, directly the nobel commitee. Because you've just proved that some 
very basic physical laws are wrong.
Stefan
Stefan
July 21st 06, 03:18 PM
T o d d P a t t i s t schrieb:
> Dudley's description of the classic competition BR, the
There is no such thing as a competition barrel roll.
> it a BR, what do you call it?  The question is: How far off
> the classic definition do you want to allow before you stop
> calling it a BR?
Because the BR isn't a competition maneuvre, there is no exact 
definition. The best definition is the one you cited: Fly it as if the 
wheels rolled inside a barrel. But at which angle they do so, or how big 
  the diameter of said barrel should be, is completely undefined.
It's the same thing as with the wing over or the lazy eight.
Stefan
Dudley Henriques[_1_]
July 21st 06, 03:56 PM
"Stefan" > wrote in message 
 ...
>T o d d P a t t i s t schrieb:
>
>> Dudley's description of the classic competition BR, the
>
> There is no such thing as a competition barrel roll.
You are correct. Barrel rolls are not used in competition aerobatics. It's 
notable that aileron rolls are also not used in competitive aerobatics.
Both of these maneuvers however are useful to demonstration pilots flying 
high performance airplanes with reasonable roll rates in specific situations 
where speed of execution rather than ground contact is desired.
For example, demonstrating a fighter like a P51 or an F8F, it can be an 
advantage to use an aileron roll or a barrel roll during the run in to a 
maneuvering pass out of a horizontal turn around. However, once into the 
pass, all rolls should be slow rolls where the aircraft is "flown" all the 
way through the roll with reference to height of the longitudinal axis 
referenced to the ground.
This is a great help in staying alive in this environment :-)
Personally, for demonstration work, I always liked barrel rolls where it was 
safe to use them. In high performance airplanes they are very graceful and 
beautiful to watch from the ground and place very little strain on the 
airframe.
Dudley Henriques
Jim Macklin
July 21st 06, 04:17 PM
I've always used rudder and elevator to hold the nose on a 
point when rolling, the roll being done with aileron and the 
nose held on the point with sometime uncoordinated use of 
the controls.  I've never flown in competition.  Never done 
slow or hesitation rolls.  If I had my way, I'd do a hundred 
hammerheads for every roll.
Which acro site, give a link and I'll check it out.
-- 
James H. Macklin
ATP,CFI,A&P
"Morgans" > wrote in message 
...
|
| "Jim Macklin" > wrote
|
| > Visual aid... take a model airplane, hold it between 
your
| > finger tips on the nose and tail.  Rotate it so it turns 
on
| > the fuselage.  That's a plain roll or aileron roll.
|
| According to the acro site someone posted before, that is 
a slow roll.  An
| aileron roll requires establishing a slight up line, 
putting ailerons over,
| but not trying to hold the line with the elevator or 
rudder, so that when
| the rotation stops at wings level, you are on a slight 
down line.
| -- 
| Jim in NC
|
Ron Natalie
July 21st 06, 04:21 PM
Jim Macklin wrote:
> Then why a C172 with 4 seats.  Fools always carry a witness.
> 
> 
The most dangerous incidents in aviation are often proceded
by "Watch this."
Bob Moore
July 21st 06, 04:22 PM
T o d d P a t t i s t wrote
> A barrel roll is often described as: "imagine the wheels of
> the aircraft  rolling on the inside of a barrel."  In
> Dudley's description of the classic competition BR, the
> track of those wheels is going perpendicular to the axis of
> the barrel at the top, straight down the axis of the barrel
> at the beginning and end, and the barrel is perfectly round.
> In Dudley's expanded description of the BR (as any roll in
> 3D) the track might not be perpendicular at the top and the
> barrel might not be perfectly round.
Todd, in your example, the wheels would "scuff" around the
inside of the barrel. In order to roll around the inside of
the barrel. The starting heading must be some number of degrees
off the axis of the barrel, 45 degrees in the classic example.
At the top of the barrel, the heading would have changed by 90
degrees, but would be 45 degrees off the axis of the barrel on
the other side.
Bob Moore
Stefan
July 21st 06, 04:23 PM
T o d d P a t t i s t schrieb:
>> There is no such thing as a competition barrel roll.
> The only aerobatics competition I've flown was in radio
> control airplanes in the 1970's.  It was pretty informal,
> but we flew BR's and were judged on them.
Of course you can do competitions any way you want and judge whatever 
you like. (And barrel rolls are beautiful to watch.) In this respect, I 
should have written "not an FAI competition figure".
BTW, where I live and fly, this year's known programme for the beginners 
class in glider aerobatics contains a wing over. Not an FAI figure 
either. No problem, at the briefing, the chief judge will explain what 
he thinks a wing over should look like, and then it will be judged 
according to his guide lines.
Stefan
Ron Natalie
July 21st 06, 04:30 PM
Big John wrote:
> Andrey
> 
> As has been said in all the posts, the short answer is NO. 172 is not
> certified to do barrel rolls.
> 
> However I can barrel roll a 172 only pulling 1 G which puts no more
> load on airframe than straight and level flight. I have thousands of
> hours to back up my statement.
> 
No you can not.
It's not possible to even start the roll without going greater
than 1G.
Morgans[_3_]
July 21st 06, 04:31 PM
"Jim Macklin" > wrote
> Visual aid... take a model airplane, hold it between your
> finger tips on the nose and tail.  Rotate it so it turns on
> the fuselage.  That's a plain roll or aileron roll.
According to the acro site someone posted before, that is a slow roll.  An
aileron roll requires establishing a slight up line, putting ailerons over,
but not trying to hold the line with the elevator or rudder, so that when
the rotation stops at wings level, you are on a slight down line.
-- 
Jim in NC
Ron Natalie
July 21st 06, 04:32 PM
Matt Whiting wrote:
> Your thousands of hours aside, this is simply an incorrect statement.  A 
> barrel roll requires flying a loop and you can't fly a loop at 1 G.  It 
> sounds like you are describing an aileron roll.
> 
You can't even do an aileron roll without exceeding 1G.
Small g's sure, but you gotta go > 1 to do just about anything.
Stefan
July 21st 06, 04:42 PM
Jim Macklin schrieb:
> I've always used rudder and elevator to hold the nose on a 
> point when rolling, the roll being done with aileron and the 
> nose held on the point with sometime uncoordinated use of 
> the controls.
Hopefully your use of the controls in a roll are well coordinated. Which 
doesn't mean the ball stays in the middle.
Stefan
Dudley Henriques[_1_]
July 21st 06, 04:43 PM
Ron;
I think what might be happening here is that some folks are defining the 
roll from the set point rather than from level flight. It's true that any 
raising of the nose from level flight will require more than 1 g, but once 
at the set point and initiating the roll (aileron roll) you can unload the 
airplane all the way down to 0 g if you like right up to the backside 
recovery to level flight, where the g of course has to be returned.
Dudley Henriques
"Ron Natalie" > wrote in message 
 m...
> Big John wrote:
>> Andrey
>>
>> As has been said in all the posts, the short answer is NO. 172 is not
>> certified to do barrel rolls.
>>
>> However I can barrel roll a 172 only pulling 1 G which puts no more
>> load on airframe than straight and level flight. I have thousands of
>> hours to back up my statement.
>>
> No you can not.
>
> It's not possible to even start the roll without going greater
> than 1G.
RST Engineering
July 21st 06, 05:00 PM
That would be, "Hey, y'all, hold my beer and watch this."
Jim
> The most dangerous incidents in aviation are often proceded
> by "Watch this."
Morgans[_3_]
July 21st 06, 05:45 PM
"Jim Macklin" > wrote in message
news:Ol5wg.79455$ZW3.31376@dukeread04...
> I've always used rudder and elevator to hold the nose on a
> point when rolling, the roll being done with aileron and the
> nose held on the point with sometime uncoordinated use of
> the controls.  I've never flown in competition.  Never done
> slow or hesitation rolls.  If I had my way, I'd do a hundred
> hammerheads for every roll.
I had called that an aileron roll, but from the site, that is a slow roll,
even if it is done fast! <g>
> Which acro site, give a link and I'll check it out.
http://www.iac.org/begin/figures.html#Aileron%20Rolls
Good site.
-- 
Jim in NC
john smith
July 21st 06, 06:31 PM
> >> As has been said in all the posts, the short answer is NO. 172 is not
> >> certified to do barrel rolls.
> >> However I can barrel roll a 172 only pulling 1 G which puts no more
> >> load on airframe than straight and level flight. I have thousands of
> >> hours to back up my statement.
> > No you can not.
> > It's not possible to even start the roll without going greater
> > than 1G. 
> Ron;
> I think what might be happening here is that some folks are defining the 
> roll from the set point rather than from level flight. It's true that any 
> raising of the nose from level flight will require more than 1 g, but once 
> at the set point and initiating the roll (aileron roll) you can unload the 
> airplane all the way down to 0 g if you like right up to the backside 
> recovery to level flight, where the g of course has to be returned.
> Dudley Henriques
Dudley, they are not paying attention. They are thinking every maneuver 
has to start and be flown from the straight and level. They don't think 
in terms of up/down-lines at any angle.
ie.... Reverse half-Cuban with a barrel roll on the down 45.
Big John
July 21st 06, 06:33 PM
Stefan
Have done many in real life.
Go to Google and research Barrel Rolls. You will find links that show
you can do them between 0.5 G's and max G's bird is certified for. 
Beside these 'experts' who posted, all I can say is fly the airplane.
If you want 1 G then fly it that way. If you can't fly it that way
then don't get in bird as you are an accident waiting to happen.
Big John
``````````````````````````````````
On Fri, 21 Jul 2006 11:10:53 +0200, Stefan >
wrote:
>Big John schrieb:
>
>> I'm glad your the expert.
>
>I'm far from being an expert, but I have an idea, yes.
>
>> I used to do half of a barrel roll at one G and give to student under
>
>If you can actually do a barrel roll without exceeding 1g at any point, 
>then you should immediately inform your local university. Or, better 
>yet, directly the nobel commitee. Because you've just proved that some 
>very basic physical laws are wrong.
>
>Stefan
Big John
July 21st 06, 06:41 PM
Jim
You explained what has been known as a 'slow roll' since I started
flying heavy iron in the 40's. Have heard them called point rolls also
but only on rare occasions.
I thinK Stephen may be a Troll from his postings. I'm going to stop
trying to feed him :o(
Big John
`````````````````````````````````````````````````` ```````
On Fri, 21 Jul 2006 09:17:40 -0500, "Jim Macklin"
> wrote:
>I've always used rudder and elevator to hold the nose on a 
>point when rolling, the roll being done with aileron and the 
>nose held on the point with sometime uncoordinated use of 
>the controls.  I've never flown in competition.  Never done 
>slow or hesitation rolls.  If I had my way, I'd do a hundred 
>hammerheads for every roll.
>
>Which acro site, give a link and I'll check it out.
Bob Moore
July 21st 06, 06:49 PM
T o d d P a t t i s t wrote
> Starting the BR with the aircraft track at 90 degrees to the
> barrel produces a loop (no roll portion to the BR).
> Starting it parallel to the barrel (and reducing the
> diameter of the barrel to zero) makes it into an aileron
> roll (no loop portion to the BR).  Everything in between is
> possible, and at some point on either side as you get closer
> to the loop or aileron roll, you've got to stop calling it a
> BR.
You might not have his thousands of hours, but you certainly
understand a lot more about barrel rolls than does Big John.
:-)  :-) Of course, what can you expect from a person who flys
"birds" instead of "airplanes". :-)
May be some definitions...:-)
Barrel Roll....................45 degrees off axis
Aileron roll...................00 degrees off axis
Loop...........................90 degrees off axis
Sloppy barrel roll......22.5-67.5 degrees off axis 
Sloppy aileron roll.......01-22.5 degrees off axis
Sloppy loop...............67.5-89 degrees off axis
                
Bob Moore
Larry Dighera
July 21st 06, 07:03 PM
On Fri, 21 Jul 2006 16:49:49 GMT, Bob Moore >
wrote in >::
>
>May be some definitions...:-)
>
>Barrel Roll....................45 degrees off axis
>Aileron roll...................00 degrees off axis
>Loop...........................90 degrees off axis
>Sloppy barrel roll......22.5-67.5 degrees off axis 
>Sloppy aileron roll.......01-22.5 degrees off axis
>Sloppy loop...............67.5-89 degrees off axis
This refers to the direction of flight relative to the longitudinal
axis of the aircraft?
Big John
July 21st 06, 07:12 PM
Ron
Wrong choice of words.
Straight and level your G meter reads one G,(force of gravity) if
calabrated correctly. You roll into a turn and pull one G (2 G's on
meter) to make a one G turn. Please correct my posts to show this. 
I should have said two G's on meter and things would work out. Sorry
about that :o(
Big John
`````````````````````````````````````````````````` ``````````
On Fri, 21 Jul 2006 10:30:11 -0400, Ron Natalie >
wrote:
>Big John wrote:
>> Andrey
>> 
>> As has been said in all the posts, the short answer is NO. 172 is not
>> certified to do barrel rolls.
>> 
>> However I can barrel roll a 172 only pulling 1 G which puts no more
>> load on airframe than straight and level flight. I have thousands of
>> hours to back up my statement.
>> 
>No you can not.
>
>It's not possible to even start the roll without going greater
>than 1G.
Big John
July 21st 06, 07:28 PM
Dudley
Can it be said?
In a Barrel Roll the ball starts centered and stays centered
throughout the roll until aircraft returns to straight and level
flight and starts some other maneuver.
In a Slow Roll (sometimes called Point Roll) the ball starts centered
and is then never centered except momentarily when bird has rolled 180
degrees and is inverted, until completion of roll and return to
straight and level flight?
Rolls are easy to explain face to face in briefing using hands or
models and demo in air, but over Internet the nuances of English make
it difficult.
Big John
`````````````````````````````````````````````````` `````````
On Fri, 21 Jul 2006 14:43:10 GMT, "Dudley Henriques"
> wrote:
>Ron;
>I think what might be happening here is that some folks are defining the 
>roll from the set point rather than from level flight. It's true that any 
>raising of the nose from level flight will require more than 1 g, but once 
>at the set point and initiating the roll (aileron roll) you can unload the 
>airplane all the way down to 0 g if you like right up to the backside 
>recovery to level flight, where the g of course has to be returned.
>Dudley Henriques
>
>"Ron Natalie" > wrote in message 
 m...
>> Big John wrote:
>>> Andrey
>>>
>>> As has been said in all the posts, the short answer is NO. 172 is not
>>> certified to do barrel rolls.
>>>
>>> However I can barrel roll a 172 only pulling 1 G which puts no more
>>> load on airframe than straight and level flight. I have thousands of
>>> hours to back up my statement.
>>>
>> No you can not.
>>
>> It's not possible to even start the roll without going greater
>> than 1G. 
>
Terry[_1_]
July 21st 06, 10:14 PM
Morgans wrote:
> "john smith" > wrote
> 
>> Certified? No.
>> Possible? Yes, but you will finish much lower than where you started.
> 
> Don't encourage that type of behavior with a yes.  If he had to ask, he is
> probably not a competent aerobatic pilot, and a blown barrel roll could
> stall the plane, or overstress it, so it fails then, or later.
> 
> I'll bet he is not going to wear a parachute, either, which is required.
> 
> The answer to rolling a normal category plane should be no, always.
> 
> We don't want his, or someone else's blood on our hands.
I am wondering why, if one may spin a 172, why one may not roll a 172 ...
Jim Macklin
July 21st 06, 11:01 PM
Already went looking and found it.  As Shake Spear said, a 
pig pen smells just like a sty.  Or was it roses?
"Morgans" > wrote in message 
...
|
| "Jim Macklin" > wrote 
in message
| news:Ol5wg.79455$ZW3.31376@dukeread04...
| > I've always used rudder and elevator to hold the nose on 
a
| > point when rolling, the roll being done with aileron and 
the
| > nose held on the point with sometime uncoordinated use 
of
| > the controls.  I've never flown in competition.  Never 
done
| > slow or hesitation rolls.  If I had my way, I'd do a 
hundred
| > hammerheads for every roll.
|
| I had called that an aileron roll, but from the site, that 
is a slow roll,
| even if it is done fast! <g>
|
| > Which acro site, give a link and I'll check it out.
|
| http://www.iac.org/begin/figures.html#Aileron%20Rolls
|
| Good site.
| -- 
| Jim in NC
|
Jim Macklin
July 21st 06, 11:04 PM
Yep, I used the wrong word/name.  Of course the redneck roll 
is finding a drunk to pay your bar bill.
"Big John" > wrote in message 
...
|
| Jim
|
| You explained what has been known as a 'slow roll' since I 
started
| flying heavy iron in the 40's. Have heard them called 
point rolls also
| but only on rare occasions.
|
| I thinK Stephen may be a Troll from his postings. I'm 
going to stop
| trying to feed him :o(
|
| Big John
| `````````````````````````````````````````````````` ```````
|
| On Fri, 21 Jul 2006 09:17:40 -0500, "Jim Macklin"
| > wrote:
|
| >I've always used rudder and elevator to hold the nose on 
a
| >point when rolling, the roll being done with aileron and 
the
| >nose held on the point with sometime uncoordinated use of
| >the controls.  I've never flown in competition.  Never 
done
| >slow or hesitation rolls.  If I had my way, I'd do a 
hundred
| >hammerheads for every roll.
| >
| >Which acro site, give a link and I'll check it out.
|
Jim Macklin
July 21st 06, 11:06 PM
Because Cessna didn't make it in the aerobatic category.
"Terry" > wrote in message 
...
| Morgans wrote:
| > "john smith" > wrote
| >
| >> Certified? No.
| >> Possible? Yes, but you will finish much lower than 
where you started.
| >
| > Don't encourage that type of behavior with a yes.  If he 
had to ask, he is
| > probably not a competent aerobatic pilot, and a blown 
barrel roll could
| > stall the plane, or overstress it, so it fails then, or 
later.
| >
| > I'll bet he is not going to wear a parachute, either, 
which is required.
| >
| > The answer to rolling a normal category plane should be 
no, always.
| >
| > We don't want his, or someone else's blood on our hands.
|
| I am wondering why, if one may spin a 172, why one may not 
roll a 172 ...
Larry Dighera
July 22nd 06, 12:36 AM
On Fri, 21 Jul 2006 13:14:38 -0700, Terry > wrote
in >::
>I am wondering why, if one may spin a 172, why one may not roll a 172 ...
    From: "Jim Macklin" >
    Newsgroups: rec.aviation.piloting
    Subject: Re: barrel roll in 172
    Message-ID: <2SQvg.78944$ZW3.35114@dukeread04>
    Date: Thu, 20 Jul 2006 14:31:05 -0500
    
    The issue is recovery from a botched barrel roll, such as in 
    inverted stall followed by a high speed dive and too strong 
    a pull on recovery.
For what maximum negative G load is the a C-172 certified in Utility
Category?  For what absolute maximum negative G load is the C-172
designed?
    From: Big John >
    Newsgroups: rec.aviation.piloting
    Subject: Re: barrel roll in 172
    Date: Thu, 20 Jul 2006 14:27:19 -0500
    Message-ID: >
    
    
    My 1971 172/Skyhawk Owneers [sic] manual shows:
    
    Utility Caategory [sic] Maneuvers
    
    Max pos G's = 4.4
    Chandelles
    Lazy Eights
    Steep Turns
    Spins
    Stalls (Except whip stalls)
    
    Acrobatics that may impose high loads should not be attempted.
Matt Whiting
July 22nd 06, 12:42 AM
Bob Moore wrote:
> T o d d P a t t i s t wrote
> 
>>A barrel roll is often described as: "imagine the wheels of
>>the aircraft  rolling on the inside of a barrel."  In
>>Dudley's description of the classic competition BR, the
>>track of those wheels is going perpendicular to the axis of
>>the barrel at the top, straight down the axis of the barrel
>>at the beginning and end, and the barrel is perfectly round.
>>In Dudley's expanded description of the BR (as any roll in
>>3D) the track might not be perpendicular at the top and the
>>barrel might not be perfectly round.
> 
> 
> Todd, in your example, the wheels would "scuff" around the
> inside of the barrel. In order to roll around the inside of
> the barrel. The starting heading must be some number of degrees
> off the axis of the barrel, 45 degrees in the classic example.
> 
> At the top of the barrel, the heading would have changed by 90
> degrees, but would be 45 degrees off the axis of the barrel on
> the other side.
Yes, the "classic" barrel roll is a helix and the angle to the 
longitudinal axis should remain constant.
Matt
Matt Whiting
July 22nd 06, 12:45 AM
Ron Natalie wrote:
> Matt Whiting wrote:
> 
>> Your thousands of hours aside, this is simply an incorrect statement.  
>> A barrel roll requires flying a loop and you can't fly a loop at 1 G.  
>> It sounds like you are describing an aileron roll.
>>
> You can't even do an aileron roll without exceeding 1G.
> Small g's sure, but you gotta go > 1 to do just about anything.
Yes, for an aileron roll as you have to raise the nose at the start. 
However, a slow roll should be able to be flown at 1G throughout, but it 
would probably take someone of Hoover's (or Dudley's) skill to do it. 
If you kept the center of mass of the airplane on the straight and level 
track you are flying at the start, it would be 1G.  The 1G wouldn't 
always be positive with respect to the top of the airplane, however, so 
I guess I should say |a|=1G  :-)
Matt
Matt Whiting
July 22nd 06, 12:47 AM
Bob Moore wrote:
> T o d d P a t t i s t wrote
> 
> 
>>Starting the BR with the aircraft track at 90 degrees to the
>>barrel produces a loop (no roll portion to the BR).
>>Starting it parallel to the barrel (and reducing the
>>diameter of the barrel to zero) makes it into an aileron
>>roll (no loop portion to the BR).  Everything in between is
>>possible, and at some point on either side as you get closer
>>to the loop or aileron roll, you've got to stop calling it a
>>BR.
> 
> 
> You might not have his thousands of hours, but you certainly
> understand a lot more about barrel rolls than does Big John.
> :-)  :-) Of course, what can you expect from a person who flys
> "birds" instead of "airplanes". :-)
> 
> May be some definitions...:-)
> 
> Barrel Roll....................45 degrees off axis
> Aileron roll...................00 degrees off axis
> Loop...........................90 degrees off axis
> Sloppy barrel roll......22.5-67.5 degrees off axis 
> Sloppy aileron roll.......01-22.5 degrees off axis
> Sloppy loop...............67.5-89 degrees off axis
I think I could do those last three!
Matt
Matt Whiting
July 22nd 06, 12:49 AM
Larry Dighera wrote:
> On Fri, 21 Jul 2006 16:49:49 GMT, Bob Moore >
> wrote in >::
> 
> 
>>May be some definitions...:-)
>>
>>Barrel Roll....................45 degrees off axis
>>Aileron roll...................00 degrees off axis
>>Loop...........................90 degrees off axis
>>Sloppy barrel roll......22.5-67.5 degrees off axis 
>>Sloppy aileron roll.......01-22.5 degrees off axis
>>Sloppy loop...............67.5-89 degrees off axis
> 
> 
> This refers to the direction of flight relative to the longitudinal
> axis of the aircraft?
> 
No, the longitudinal axis of the invisible barrel in the sky.
Unless you are in a slip or skid or stall or spin (or probably other 
things), the direction of flight is always 0 degrees off the 
longitudinal axis of the airplane.
Matt
Dudley Henriques[_1_]
July 22nd 06, 01:10 AM
"Big John" > wrote in message 
...
> Dudley
>
> Can it be said?
>
> In a Barrel Roll the ball starts centered and stays centered
> throughout the roll until aircraft returns to straight and level
> flight and starts some other maneuver.
If you are good, you can fly a barrel roll center ball. This requires a near 
perfect blend of all controls and is the right way to do the classic BR.
>
> In a Slow Roll (sometimes called Point Roll) the ball starts centered
> and is then never centered except momentarily when bird has rolled 180
> degrees and is inverted, until completion of roll and return to
> straight and level flight?
Well...almost :-) You might lose the center ball as you pull to the roll set 
point but in theory it should remain more of less centered up till roll 
initiation. Immediately after you initiate a slow roll, you will lose a 
center ball as all control input through a slow roll is done in a constantly 
changing cross control dynamic. In theory, you should have a doghouse ball 
passing through the exact inverted point, but what actually is happening at 
this point is that you will be changing rudder to regain top rudder on the 
back side, so the airplane will be in a state of transition even through 
exact inverted.
Personally, I never used a ball at all in aerobatics and I don't recommend 
using a ball to other aerobatic instructors. One of the benefits involved in 
learning to fly acro is that you learn to judge maneuver quality with your 
eyeballs on the nose attitude outside the airplane . All positioning is 
eyeball related and any unwanted yaw should be immediately apparent by 
watching the nose.
I discourage ball use even in primary students, and get their heads outside 
where it belongs as soon as possible.
All pilots should learn as soon as possible to judge turn quality from nose 
attitude behavior.
I know many...many aerobatic pilots who take the ball out of their airplanes 
simply to save the weight and space the instrument takes up on the panel.
>
> Rolls are easy to explain face to face in briefing using hands or
> models and demo in air, but over Internet the nuances of English make
> it difficult.
This can be quite true.
Dudley Henriques
>
> Big John
> `````````````````````````````````````````````````` `````````
>
> On Fri, 21 Jul 2006 14:43:10 GMT, "Dudley Henriques"
> > wrote:
>
>>Ron;
>>I think what might be happening here is that some folks are defining the
>>roll from the set point rather than from level flight. It's true that any
>>raising of the nose from level flight will require more than 1 g, but once
>>at the set point and initiating the roll (aileron roll) you can unload the
>>airplane all the way down to 0 g if you like right up to the backside
>>recovery to level flight, where the g of course has to be returned.
>>Dudley Henriques
>>
>>"Ron Natalie" > wrote in message
 m...
>>> Big John wrote:
>>>> Andrey
>>>>
>>>> As has been said in all the posts, the short answer is NO. 172 is not
>>>> certified to do barrel rolls.
>>>>
>>>> However I can barrel roll a 172 only pulling 1 G which puts no more
>>>> load on airframe than straight and level flight. I have thousands of
>>>> hours to back up my statement.
>>>>
>>> No you can not.
>>>
>>> It's not possible to even start the roll without going greater
>>> than 1G.
>>
>
Morgans[_3_]
July 22nd 06, 02:25 AM
"Jim Macklin" > wrote
> Already went looking and found it.  As Shake Spear said, a
> pig pen smells just like a sty.  Or was it roses?
So, are you saying you don't think much of the site, or what?  What is wrong
with it?
-- 
Jim in NC
Jim Macklin
July 22nd 06, 07:06 AM
No, great site, I was [should have been more clear] speaking 
to the use of the terms for types of rolls.
BTW, I've been an EAA Lifer a very long, long time.
"Morgans" > wrote in message 
...
|
| "Jim Macklin" > wrote
|
| > Already went looking and found it.  As Shake Spear said, 
a
| > pig pen smells just like a sty.  Or was it roses?
|
| So, are you saying you don't think much of the site, or 
what?  What is wrong
| with it?
| -- 
| Jim in NC
|
Larry Dighera
July 22nd 06, 08:13 PM
On Sat, 22 Jul 2006 11:35:27 -0500, Big John >
wrote in >::
>Flight load factor
>
>Flaps up = +4.4 G's and -1.76 G's
So, in inverted flight a C-172 has only a 76% of a G margin to carry
additional G force.  That isn't much.
Thanks.
Klein
July 22nd 06, 11:58 PM
On Fri, 21 Jul 2006 23:10:46 GMT, "Dudley Henriques"
> wrote:
>
>"Big John" > wrote in message 
...
>> Dudley
>>
>> Can it be said?
>>
>> In a Barrel Roll the ball starts centered and stays centered
>> throughout the roll until aircraft returns to straight and level
>> flight and starts some other maneuver.
>
>If you are good, you can fly a barrel roll center ball. This requires a near 
>perfect blend of all controls and is the right way to do the classic BR.
>>
>> In a Slow Roll (sometimes called Point Roll) the ball starts centered
>> and is then never centered except momentarily when bird has rolled 180
>> degrees and is inverted, until completion of roll and return to
>> straight and level flight?
>
>Well...almost :-) You might lose the center ball as you pull to the roll set 
>point but in theory it should remain more of less centered up till roll 
>initiation. Immediately after you initiate a slow roll, you will lose a 
>center ball as all control input through a slow roll is done in a constantly 
>changing cross control dynamic. In theory, you should have a doghouse ball 
>passing through the exact inverted point, but what actually is happening at 
>this point is that you will be changing rudder to regain top rudder on the 
>back side, so the airplane will be in a state of transition even through 
>exact inverted.
>Personally, I never used a ball at all in aerobatics and I don't recommend 
>using a ball to other aerobatic instructors. One of the benefits involved in 
>learning to fly acro is that you learn to judge maneuver quality with your 
>eyeballs on the nose attitude outside the airplane . All positioning is 
>eyeball related and any unwanted yaw should be immediately apparent by 
>watching the nose.
>I discourage ball use even in primary students, and get their heads outside 
>where it belongs as soon as possible.
>All pilots should learn as soon as possible to judge turn quality from nose 
>attitude behavior.
>I know many...many aerobatic pilots who take the ball out of their airplanes 
>simply to save the weight and space the instrument takes up on the panel.
>
>>
>> Rolls are easy to explain face to face in briefing using hands or
>> models and demo in air, but over Internet the nuances of English make
>> it difficult.
>
>This can be quite true.
>
>Dudley Henriques
>
>>
>> Big John
>> `````````````````````````````````````````````````` `````````
>>
>> On Fri, 21 Jul 2006 14:43:10 GMT, "Dudley Henriques"
>> > wrote:
>>
>>>Ron;
>>>I think what might be happening here is that some folks are defining the
>>>roll from the set point rather than from level flight. It's true that any
>>>raising of the nose from level flight will require more than 1 g, but once
>>>at the set point and initiating the roll (aileron roll) you can unload the
>>>airplane all the way down to 0 g if you like right up to the backside
>>>recovery to level flight, where the g of course has to be returned.
>>>Dudley Henriques
>>>
>>>"Ron Natalie" > wrote in message
 m...
>>>> Big John wrote:
>>>>> Andrey
>>>>>
>>>>> As has been said in all the posts, the short answer is NO. 172 is not
>>>>> certified to do barrel rolls.
>>>>>
>>>>> However I can barrel roll a 172 only pulling 1 G which puts no more
>>>>> load on airframe than straight and level flight. I have thousands of
>>>>> hours to back up my statement.
>>>>>
>>>> No you can not.
>>>>
>>>> It's not possible to even start the roll without going greater
>>>> than 1G.
Preface: I'm an IAC member and have been flying competitions since '95
in Yaks, Sukhois and Extras and also in unlimited gliders.  I have
also held an FAA form 8710-7 card for air shows. (not current)
This morning I went out to play with some barrel rolls in the Extra
300.  I'd like to offer that no one has yet mentioned that you can fly
very different sorts of barrel rolls where the main variable is the
amount the nose deflects from level flight.  I think the "fighter
pilot" sort of barrel roll that is done to avoid overshooting an
opponent or to cause a following opponent to overshoot you is
typically done with not so much upward and downward nose deflection
from level.  If you start an aileron  roll and add in just a touch of
back stick at the beginning and end with a bit of push while inverted,
you'll fly a very tight barrel roll with minimal nose deflection.  On
the other hand, if you use a lot of nose deflection so that the nose
goes all the way to vertical, you make a very different looking
barrel roll.  THIS is the barrel roll that you can say is a
combination of a roll and a loop.  
People are claiming 1 g barrel rolls can be performed.  Nope.  Not if
you are starting and ending in level flight.  On a ballistic
trajectory, maybe.  This is especially true for the big barrel roll
which can be said to be a combined roll and loop.  A round loop
requires at least 3.5 - 4 g.  I usually use around 6 g at the
beginning and end of my loops to make them look nice and round.  To
get a similar barrel roll requires similar g levels.  
It has been said in this thread that "there is no competition barrel
roll".  That is about half true.  There used to be (long before I got
into it) a competition barrel roll but it was deleted from the
catalog.  The current catalog of figures has a pair of figures called
"quarter clovers".  Each of these consist of half a barrel roll and
half of a loop.  In one, as you pull into a loop, you put in some
aileron.  You continue with the rolling until you reach the top of the
loop.  At this point, you are inverted, level and have turned the nose
90 degrees from the original flight direction.  You then center the
ailerons and fly the bottom half of a loop back to straight and level.
The other quarter clover is done in the opposite manner, i.e., the
first half of the figure is a half loop with no rolling.  The second
half of the figure combines aileron input with elevator to return to
straight and level upright flight but with a 90 degree heading change
from the original direction of flight.  
I think these are called quarter clovers because if you did four of
them in succession with the smoke on, (and no wind) you'd make a nice
4-leaf clover figure in the sky.  
If you performed the first half of the first quarter clover and the
second half from the second quarter clover, with the same aileron
deflection on both halves, you'd fly the classic really big barrel
roll.  
These figures were first used for aerobatic glider competitions and
then were also recently used in the Sportsman "known" sequence.  I've
never seen them flown at higher levels of competition.
Many times, competitors are downgraded for "barreling" a "slow" roll.
Note that the word slow means nothing for the speed of rolling.  In a
slow roll the fuselage does not deflect during the roll.  An aileron
roll is one where you begin with a pull to get some nose up
deflection, followed by a return to 1 g (or less) and the aileron
deflection to roll about the longitudinal axis.  After return to wings
level, the nose may have dropped below horizontal and will need a
little pull to return to level.  A fast rolling airplane (like a
Sukhoi or Extra) can complete the roll so quickly that the aileron
roll and slow roll look the same and are performed the same.  A
barreled roll would have discernable nose deflection during the course
of the roll. Most competitors have this happen to them on the last
half of a full roll.  This defect is also called "dished".  I think it
usually happens because the pilot uses inadequate push while inverted,
allowing the nose to drop from the horizontal.  If doing it at low
level, you can find yourself at zero altitude (or less), as Dudley has
pointed out.  :-(
In unlimited glider aerobatic competitions there is a figure called
the "super slow roll" where a 360 degree roll must take AT LEAST 10
seconds to perform.  The chief judge times you and if you do it too
fast, you "zero" the figure.  Or course, there is lots of opportunity
for every little defect in technique to become obvious to the judges.
A "point" roll is one where the rolling is stopped briefly and
restarted one or more times - also sometimes called a "hesitation
roll".  E.g., a four point roll would consist of 4 - 90 degree rolls
in the same direction with a brief pause between each of the 90 degree
rolls for a total of 360 degrees of rolling to get back to the
starting attitude.  
I agree with the point made about using the ball during acro.  I never
look at mine and my aerobatic glider doesn't even have one.  Doesn't
have a yaw string either.  :-0  I don't need it.
Happy landings,
Klein
Dudley Henriques[_1_]
July 23rd 06, 12:26 AM
"Klein" > wrote in message 
...
> On Fri, 21 Jul 2006 23:10:46 GMT, "Dudley Henriques"
> > wrote:
> In unlimited glider aerobatic competitions there is a figure called
> the "super slow roll" where a 360 degree roll must take AT LEAST 10
> seconds to perform.
I love the super slow roll, and consider it one of the harder maneuvers to 
perform correctly in demonstration work.
I once did one in an S1S Pitts the entire length of Dulles Airport. Takes 
tremendous timing and coordination in the Pitts. I used my fingertips on the 
stick and braced my heels solidly on the floor using my ankles as fulcrums 
on the rudder for this maneuver; (which I always did anyway :-) .
Dudley Henriques
Matt Whiting
July 23rd 06, 03:54 AM
Larry Dighera wrote:
> On Sat, 22 Jul 2006 11:35:27 -0500, Big John >
> wrote in >::
> 
> 
>>Flight load factor
>>
>>Flaps up = +4.4 G's and -1.76 G's
> 
> 
> So, in inverted flight a C-172 has only a 76% of a G margin to carry
> additional G force.  That isn't much.
> 
> Thanks.
No, 176% of a G.
Matt
Larry Dighera
July 23rd 06, 08:02 AM
On Sun, 23 Jul 2006 01:54:35 GMT, Matt Whiting >
wrote in >::
>>>Flight load factor
>>>
>>>Flaps up = +4.4 G's and -1.76 G's
>> 
>> 
>> So, in inverted flight a C-172 has only a 76% of a G margin to carry
>> additional G force.  That isn't much.
>> 
>> Thanks.
>
>No, 176% of a G.
No. A _margin_ of only a 76% of a G to carry G forces in addition to
the one G natural force.
Matt Whiting
July 23rd 06, 04:00 PM
Larry Dighera wrote:
> On Sun, 23 Jul 2006 01:54:35 GMT, Matt Whiting >
> wrote in >::
> 
> 
>>>>Flight load factor
>>>>
>>>>Flaps up = +4.4 G's and -1.76 G's
>>>
>>>
>>>So, in inverted flight a C-172 has only a 76% of a G margin to carry
>>>additional G force.  That isn't much.
>>>
>>>Thanks.
>>
>>No, 176% of a G.
> 
> 
> No. A _margin_ of only a 76% of a G to carry G forces in addition to
> the one G natural force.
When you are pulling negative G, there is no one natural G force.  It 
takes -1 G of acceleration to counter gravity and get you to 0 G.  You 
can then add -1.76 G of additional acceleration and still be within load 
limits.  The negative G load factor is referenced to 0 G, not 1 G 
straight and level.
Matt
john smith
July 23rd 06, 06:24 PM
In article >,
 Matt Whiting > wrote:
> When you are pulling negative G, there is no one natural G force.  It 
> takes -1 G of acceleration to counter gravity and get you to 0 G.  You 
> can then add -1.76 G of additional acceleration and still be within load 
> limits.  The negative G load factor is referenced to 0 G, not 1 G 
> straight and level.
Is negative G an up force or a down force?
Larry Dighera
July 23rd 06, 08:10 PM
On Sun, 23 Jul 2006 14:00:37 GMT, Matt Whiting >
wrote in >::
>Larry Dighera wrote:
>
>> On Sun, 23 Jul 2006 01:54:35 GMT, Matt Whiting >
>> wrote in >::
>> 
>> 
>>>>>Flight load factor
>>>>>
>>>>>Flaps up = +4.4 G's and -1.76 G's
>>>>
>>>>
>>>>So, in inverted flight a C-172 has only a 76% of a G margin to carry
>>>>additional G force.  That isn't much.
>>>>
>>>>Thanks.
>>>
>>>No, 176% of a G.
>> 
>> 
>> No. A _margin_ of only a 76% of a G to carry G forces in addition to
>> the one G natural force.
>
>When you are pulling negative G, there is no one natural G force.  
While you are in the vicinity of the Earth, your aircraft is being
acted upon by the Earth's one G gravitational force.  
If you are flying straight and level while inverted, the airframe is
experiencing -1G, not 0 G.
That provides the remaining 0.76 (76%) of a G of the C-172's negative
load factor specification of -1.76 to carry the load of any
acceleration that may subsequently occur.
>It takes -1 G of acceleration to counter gravity and get you to 0 G.
Agreed.  
>You can then add -1.76 G of additional acceleration and still be within load 
>limits.  
That analysis presumes the aircraft is not inverted.
>The negative G load factor is referenced to 0 G, not 1 G 
>straight and level.
Are not both the positive and negative load factors referenced to 0 G?
You don't set your G-meter to 0 when you are on the taxiway; you set
it to read 1 G, right?
We were discussing the negative load that might be encountered during
the inverted recovery from a barrel roll, so the earth's gravity would
add to any accelerative force while the aircraft is inverted, right?
Morgans[_3_]
July 23rd 06, 09:13 PM
"john smith" > wrote in message
...
> In article >,
>  Matt Whiting > wrote:
>
> > When you are pulling negative G, there is no one natural G force.  It
> > takes -1 G of acceleration to counter gravity and get you to 0 G.  You
> > can then add -1.76 G of additional acceleration and still be within load
> > limits.  The negative G load factor is referenced to 0 G, not 1 G
> > straight and level.
>
> Is negative G an up force or a down force?
I'll disagree, here.
Straight level flight, right side up is 1 G
Free-fall, so you are not touching the seat or seatbelt is O G
Straight level flight upside down, is -1G
If the plane is upside down, and pushes up elevator, until a100KG weight
weighs 176KG, that is a -1.76 G factor.  Not much extra for upside down
flight, is it.
-- 
Jim in NC
RomeoMike
July 23rd 06, 10:18 PM
Larry Dighera wrote:
> 
> We were discussing the negative load that might be encountered during
> the inverted recovery from a barrel roll
If the barrel roll is performed correctly it is a +G maneuver 
throughout, even while inverted.
Larry Dighera
July 24th 06, 01:10 AM
On Sun, 23 Jul 2006 14:18:23 -0600, RomeoMike
> wrote in
>::
>Larry Dighera wrote:
>
>> 
>> We were discussing the negative load that might be encountered during
>> the inverted recovery from a barrel roll
>
>If the barrel roll is performed correctly it is a +G maneuver 
>throughout, even while inverted.
While that may be true, it isn't pertinent to this branch of this
message thread:
    From: "Jim Macklin" >
    Newsgroups: rec.aviation.piloting
    Subject: Re: barrel roll in 172
    Message-ID: <2SQvg.78944$ZW3.35114@dukeread04>
    Date: Thu, 20 Jul 2006 14:31:05 -0500
    
    The issue is recovery from a botched barrel roll, such as in 
    inverted stall followed by a high speed dive and too strong 
    a pull on recovery.
Jay Beckman
July 25th 06, 06:36 AM
"Jim Macklin" > wrote in message 
news:_aMvg.78918$ZW3.55764@dukeread04...
> Didn't Lorena Bobbitt say that?
Not sure if we've ever seen the entire quote as her post was "snipped."
Jay B
Matt Whiting
July 26th 06, 12:09 AM
john smith wrote:
> In article >,
>  Matt Whiting > wrote:
> 
> 
>>When you are pulling negative G, there is no one natural G force.  It 
>>takes -1 G of acceleration to counter gravity and get you to 0 G.  You 
>>can then add -1.76 G of additional acceleration and still be within load 
>>limits.  The negative G load factor is referenced to 0 G, not 1 G 
>>straight and level.
> 
> 
> Is negative G an up force or a down force?
It is an acceleration opposite the normal acceleration due to gravity, 
so it would be downward with respect to the airframe.
Matt
Matt Whiting
July 26th 06, 12:12 AM
Larry Dighera wrote:
> On Sun, 23 Jul 2006 14:00:37 GMT, Matt Whiting >
> wrote in >::
> 
> 
>>Larry Dighera wrote:
>>
>>
>>>On Sun, 23 Jul 2006 01:54:35 GMT, Matt Whiting >
>>>wrote in >::
>>>
>>>
>>>
>>>>>>Flight load factor
>>>>>>
>>>>>>Flaps up = +4.4 G's and -1.76 G's
>>>>>
>>>>>
>>>>>So, in inverted flight a C-172 has only a 76% of a G margin to carry
>>>>>additional G force.  That isn't much.
>>>>>
>>>>>Thanks.
>>>>
>>>>No, 176% of a G.
>>>
>>>
>>>No. A _margin_ of only a 76% of a G to carry G forces in addition to
>>>the one G natural force.
>>
>>When you are pulling negative G, there is no one natural G force.  
> 
> 
> While you are in the vicinity of the Earth, your aircraft is being
> acted upon by the Earth's one G gravitational force.  
> 
> If you are flying straight and level while inverted, the airframe is
> experiencing -1G, not 0 G.
> 
> That provides the remaining 0.76 (76%) of a G of the C-172's negative
> load factor specification of -1.76 to carry the load of any
> acceleration that may subsequently occur.
If you had said 76% of a negative 1 G, I'd have agreed with you.  :-)
Just saying of a G, implies positive 1 G by most conventions.
Matt
Peter R.
July 26th 06, 12:21 AM
Matt Whiting > wrote:
> It is an acceleration opposite the normal acceleration due to gravity, 
> so it would be downward with respect to the airframe.
What about the case of a fighter jet climbing on afterburners at a steep
nose-high attitude quickly rolling forward through the horizon to a steep
nose-low attitude?  Wouldn't the negative G force be considered an upward
force with respect to the airframe?
 
-- 
Peter
Larry Dighera
July 26th 06, 01:17 AM
On Tue, 25 Jul 2006 18:21:54 -0400, "Peter R." >
wrote in >::
>Matt Whiting > wrote:
>
>> It is an acceleration opposite the normal acceleration due to gravity, 
>> so it would be downward with respect to the airframe.
>
>What about the case of a fighter jet climbing on afterburners at a steep
>nose-high attitude quickly rolling forward through the horizon to a steep
>nose-low attitude?  Wouldn't the negative G force be considered an upward
>force with respect to the airframe?
>
Of course.
john smith
August 1st 06, 03:24 AM
In article >,
 Matt Whiting > wrote:
> Just saying of a G, implies positive 1 G by most conventions.
More accurately, doesn't it depend on your frame of reference?
JerryGirrafe
August 1st 06, 08:00 AM
Andrey Serbinenko wrote:
> If kept within the normal category load limits, is 172 certified to do
> barrel rolls?
>
> Andrey
No, but you can do a slip-short split-S if you so desire. I've only
done one in a low wing, but keeping positive 1g throughout is
necessary. They don't have the roll rate of an edge 540 so I don't know
why you would even want to do anything like a barrel roll in a training
aircraft. I like your live on the edge spirit though!!
Jim Macklin
August 1st 06, 10:47 AM
(5) Model 172L (1972 model)
"This airplane must be operated in compliance with the 
operating limitations
as stated in the form of placards, markings, and manuals:
MAXIMUMS
Normal Category Utility Category
Maneuvering speed (CAS) 122 mph (106 knots) 122 mph (106 
knots)
Gross weight 2300 lbs. 2000 lbs.
Flight load factor
Flaps up +3.8 -1.52 +4.4 -1.76
Flaps down +3.5 +3.5
Normal category - No acrobatic maneuvers including spins 
approved
Utility category - Baggage compartment and rear seat must 
not be occupied.
No acrobatic maneuvers approved except those listed below.
Maneuver Max. Entry speed
Chandelles 122 mph (106 knots)
Lazy eights 122 mph (106 knots)
Steep turns 122 mph (106 knots)
Spins Slow deceleration
Stalls (except whip stalls) Slow deceleration"
Spin recovery: opposite rudder - forward elevator - 
neutralize controls.
Intentional spins with flaps extended are prohibited. Known 
icing conditions to
be avoided. This airplane is certified for the following 
flight operations as of date
of original airworthiness certificate:
(DAY NIGHT VFR IFR)" (as applicable)
Download the entire TCDS here 
http://www.airweb.faa.gov/Regulatory_and_Guidance_library/rgMakeModel.nsf/0/75D0BC50E05D67D88625712500572E84?OpenDocument
"JerryGirrafe" > wrote in 
message 
 ups.com...
|
| Andrey Serbinenko wrote:
| > If kept within the normal category load limits, is 172 
certified to do
| > barrel rolls?
| >
| > Andrey
|
| No, but you can do a slip-short split-S if you so desire. 
I've only
| done one in a low wing, but keeping positive 1g throughout 
is
| necessary. They don't have the roll rate of an edge 540 so 
I don't know
| why you would even want to do anything like a barrel roll 
in a training
| aircraft. I like your live on the edge spirit though!!
|
Bob Moore
August 1st 06, 01:57 PM
Jim Macklin wrote
> (5) Model 172L (1972 model)
> "This airplane must be operated in compliance with the 
> operating limitations as stated in the form of placards, 
> markings, and manuals:
Yeah Jim, and we all MUST comply with all highway speed limits,
even when they were 55 mph.  Hell...my speedometer even had a 
big red mark at 55 mph.
A lot of those placards, markings, and manual limits are just
because the manufacturer did not want to spend the time and
money in order to seek certification for a particular item.
Such is the case of the "no slips with flaps" contained in the
manual for a lot of the C-172s.
Bob Moore
Larry Dighera
August 1st 06, 05:27 PM
On Tue, 01 Aug 2006 11:57:10 GMT, Bob Moore >
wrote in >::
>A lot of those placards, markings, and manual limits are just
>because the manufacturer did not want to spend the time and
>money in order to seek certification for a particular item.
>
>Such is the case of the "no slips with flaps" contained in the
>manual for a lot of the C-172s.
From:  (Jackie Murray)
Newsgroups: rec.aviation.piloting
Subject: Cessna 172 slips with flaps
Date: 5 Jul 1994 15:06:35 -0400
Message-ID: >
NNTP-Posting-Host: 141.114.130.70
I know this has been beaten to death, but I just received an article
from AOPA about the C172 and there is a reference to this problem.
Article: "Anatomy of a Success" (The makings of a winner) by Thomas A.
Horne, AOPA Pilot in May, 1992. In describing the phenomenal success 
and popularity of this plane when introduced in 1955, the author says
this:
"There was -- and still is -- one handling quirk: In a forward slip
with flaps extended, a 172 could pitch nose down, violently enough to
push a pilot against his seat belt. This is caused by an upturned
aileron's reducing the normally strong downwash of air over the
horizontal tail. Though puzzling in its infrequency, Cessna saw the
potential for trouble. Consequently, a placard is installed near the
flap control: Avoid slips with flaps extended."
Message-ID: >
An added note in this article...I am still reading it....in 1972 the 
'dorsal fin was extended all the way forward to the rear window. This 
helped virtually eliminate the nose-down pitch problem in sideslips
and made the airplane much more spin resistant....Cessna received
complaints from some flight instructors because of this
characteristic. Demonstrations of fully developed (three-turn) spins
were difficult to perform; result was usually a spiral"
Jose[_1_]
August 1st 06, 05:45 PM
> Cessna received
> complaints from some flight instructors because of this
> characteristic. Demonstrations of fully developed (three-turn) spins
> were difficult to perform; result was usually a spiral"
Interesting.  Cessna creates a safer airplane, and people complain.
Jose
-- 
The monkey turns the crank and thinks he's making the music.
for Email, make the obvious change in the address.
Bob Moore
August 1st 06, 06:01 PM
Larry Dighera wrote
> I know this has been beaten to death, but I just received an article
> from AOPA about the C172 and there is a reference to this problem.
> Article: "Anatomy of a Success" (The makings of a winner) by Thomas A.
> Horne, AOPA Pilot in May, 1992. 
What makes the AOPA or Thomas Horne an authority on the subject?
I have posted the following on previous occassions before and still
believe it to be true.  It is excerpted from the book, "Cessna, Wings
for the World" by William Thompson. Bill Thompson served as Manager of
Flight Test and Aerodynamics for the Cessna Aircraft Company. Seems as
if he should know the 'real' story.
Bob Moore
With the advent of the large slotted flaps in the C-170, C-180, and C-172 we encountered 
a nose down pitch in forward slips with the wing flaps deflected. In some cases it was 
severe enough to lift the pilot against his seat belt if he was slow in checking the 
motion. For this reason a caution note was placed in most of the owner's manuals under 
"Landings" reading "Slips should be avoided with flap settings greater than 30° due to a 
downward pitch encountered under certain combinations of airspeed, side-slip angle, and 
center of gravity loadings". Since wing-low drift correction in cross-wind landings is 
normally performed with a minimum flap setting (for better rudder control) this 
limitation did not apply to that maneuver. The cause of the pitching motion is the 
transition of a strong wing downwash over the tail in straight flight to a lessened 
downwash angle over part of the horizontal tail caused by the influence of a relative 
"upwash increment" from the upturned aileron in slipping flight. Although not stated in 
the owner's manuals, we privately encouraged flight instructors to explore these effects 
at high altitude, and to pass on the information to their students. This phenomenon was 
elusive and sometimes hard to duplicate, but it was thought that a pilot should be aware 
of its existence and know how to counter-act it if it occurs close to the ground.
When the larger dorsal fin was adopted in the 1972 C-172L, this side-slip pitch 
phenomenon was eliminated, but the cautionary placard was retained. In the higher-
powered C-172P and C-R172 the placard was applicable to a mild pitch "pumping" motion 
resulting from flap outboard-end vortex impingement on the horizontal tail at some 
combinations of side-slip angle, power, and airspeed.
Larry Dighera
August 1st 06, 08:49 PM
On Tue, 01 Aug 2006 16:01:39 GMT, Bob Moore >
wrote in >::
>> I just received an article
>> from AOPA about the C172 and there is a reference to this problem.
>> Article: "Anatomy of a Success" (The makings of a winner) by Thomas A.
>> Horne, AOPA Pilot in May, 1992. 
>
>What makes the AOPA or Thomas Horne an authority on the subject?
It sounds like he just paraphrased the quote you posted.
>I have posted the following on previous occassions before and still
>believe it to be true.  It is excerpted from the book, "Cessna, Wings
>for the World" by William Thompson. Bill Thompson served as Manager of
>Flight Test and Aerodynamics for the Cessna Aircraft Company. Seems as
>if he should know the 'real' story.
>
>Bob Moore
>
>With the advent of the large slotted flaps in the C-170, C-180, and C-172 we encountered 
>a nose down pitch in forward slips with the wing flaps deflected. In some cases it was 
>severe enough to lift the pilot against his seat belt if he was slow in checking the 
>motion. For this reason a caution note was placed in most of the owner's manuals under 
>"Landings" reading "Slips should be avoided with flap settings greater than 30° due to a 
>downward pitch encountered under certain combinations of airspeed, side-slip angle, and 
>center of gravity loadings". Since wing-low drift correction in cross-wind landings is 
>normally performed with a minimum flap setting (for better rudder control) this 
>limitation did not apply to that maneuver. The cause of the pitching motion is the 
>transition of a strong wing downwash over the tail in straight flight to a lessened 
>downwash angle over part of the horizontal tail caused by the influence of a relative 
>"upwash increment" from the upturned aileron in slipping flight. Although not stated in 
>the owner's manuals, we privately encouraged flight instructors to explore these effects 
>at high altitude, and to pass on the information to their students. This phenomenon was 
>elusive and sometimes hard to duplicate, but it was thought that a pilot should be aware 
>of its existence and know how to counter-act it if it occurs close to the ground.
>When the larger dorsal fin was adopted in the 1972 C-172L, this side-slip pitch 
>phenomenon was eliminated, but the cautionary placard was retained. In the higher-
>powered C-172P and C-R172 the placard was applicable to a mild pitch "pumping" motion 
>resulting from flap outboard-end vortex impingement on the horizontal tail at some 
>combinations of side-slip angle, power, and airspeed.
Jim Macklin
August 2nd 06, 04:11 PM
People were beginning to talk about all the different 
maneuver that can be done in an airplane [in this case the 
172, but this applies to all airplanes].  The OP asked about 
"normal category" but even allowing for utility category, 
the 172 is approved for very limited aerobatics.  The 
specific allowed maneuvers are listed.
Certainly, any airplane can perform any aerobatic maneuver, 
since all the controls are present for all axis.
But just as any camera can take portraits or porn, any 
airplane will only do what the pilot can do.  If your name 
is Bob Hoover  et al, you don't need to ask the question and 
you probably can do these maneuvers.  But Joe Sixpack is 
going to do several things...(a) bend the airplane (b) break 
the airplane (c) wish he had a quick jettison door (d) wish 
he had a parachute and (e) die.
Simple rule,  The Law of Gravity has no exceptions or 
appeals.
-- 
James H. Macklin
ATP,CFI,A&P
"Bob Moore" > wrote in message 
. 121...
| Jim Macklin wrote
|
| > (5) Model 172L (1972 model)
| > "This airplane must be operated in compliance with the
| > operating limitations as stated in the form of placards,
| > markings, and manuals:
|
| Yeah Jim, and we all MUST comply with all highway speed 
limits,
| even when they were 55 mph.  Hell...my speedometer even 
had a
| big red mark at 55 mph.
|
| A lot of those placards, markings, and manual limits are 
just
| because the manufacturer did not want to spend the time 
and
| money in order to seek certification for a particular 
item.
|
| Such is the case of the "no slips with flaps" contained in 
the
| manual for a lot of the C-172s.
|
| Bob Moore
Jose[_1_]
August 2nd 06, 06:31 PM
> Certainly, any airplane can perform any aerobatic maneuver, 
> since all the controls are present for all axis.
> 
> But just as any camera can take portraits or porn
Certainly not.  Not all airplanes have sufficient control authority to 
perform all aerobatic maneuvers, and not all cameras can take macros.
Jose
-- 
The monkey turns the crank and thinks he's making the music.
for Email, make the obvious change in the address.
Jim Macklin
August 2nd 06, 09:10 PM
You have to have "macros" to take porn?  "Any acrobatic 
maneuver" wasn't intended to mean 720 degree roll per second 
rate or tail slides, or but just the basic 3 axis and 
combinations.
"Jose" > wrote in message 
. ..
|> Certainly, any airplane can perform any aerobatic 
maneuver,
| > since all the controls are present for all axis.
| >
| > But just as any camera can take portraits or porn
|
| Certainly not.  Not all airplanes have sufficient control 
authority to
| perform all aerobatic maneuvers, and not all cameras can 
take macros.
|
| Jose
| -- 
| The monkey turns the crank and thinks he's making the 
music.
| for Email, make the obvious change in the address.
Stefan
August 2nd 06, 09:26 PM
Jim Macklin schrieb:
> You have to have "macros" to take porn?  "Any acrobatic 
> maneuver" wasn't intended to mean 720 degree roll per second 
> rate or tail slides, or but just the basic 3 axis and 
> combinations.
To me, "any" means "any". If you mean "some", then write "some". (Just 
as stupid as top posting.)
BTW, even your "basic" is wrong. Some airplanes cannot be rolled because 
they have too little aileron authority while inverted. (Which means that 
you can roll them to inverted, but not roll them back to upright again.)
It seems you are talking about things of which you don't have the 
slightest idea.
Stefan
Jim Macklin
August 2nd 06, 09:46 PM
Top posting comments ignored, as far as control authority, I 
sure am glad to know that recovery from an inverted position 
after en counter with wake turbulence is impossible or that 
some combined use of the ailerons, rudder and engine torque 
and P-factor can't be used to complete some maneuver, even 
if not of competition quality.
From now on and hence forth, consider that ALL STATEMENTS 
ARE INTENDED AS "GENERALIZATIONS" and the use of words such 
as "is, "always" "never" "all, "some" are not intended ort 
meant to restrict or prevent, or imply that the answer is 
legally binding, universal or written, vetted, edited, or 
even proofread.  Also, just like a legislature, each word, 
sentence or paragraph stands on its own and a finding that 
some parts is unconstitutional, invalid or just plain wrong 
does not effect the balance of the answer, question or joke. 
If you don't like the top posting you are...
free to ignore or even block the post.
or you may cut and paste it to put it at the bottom.  Since 
forwarding proof marks are added, you could even write a 
macro (a short computer program or routine) to do the edit 
for you.
Since I do not write with a pointed stick in a clay tablet, 
or use a turkey feather and my pen knife to create my 
writing tools, I am not a scribe, scriber or even a scholar. 
But hey, since I don't have any care, feel free to be 
critical.
"Stefan" > wrote in message 
 ...
| Jim Macklin schrieb:
| > You have to have "macros" to take porn?  "Any acrobatic
| > maneuver" wasn't intended to mean 720 degree roll per 
second
| > rate or tail slides, or but just the basic 3 axis and
| > combinations.
|
| To me, "any" means "any". If you mean "some", then write 
"some". (Just
| as stupid as top posting.)
|
| BTW, even your "basic" is wrong. Some airplanes cannot be 
rolled because
| they have too little aileron authority while inverted. 
(Which means that
| you can roll them to inverted, but not roll them back to 
upright again.)
|
| It seems you are talking about things of which you don't 
have the
| slightest idea.
|
| Stefan
Jose[_1_]
August 3rd 06, 12:37 AM
> You have to have "macros" to take porn?  
Depends.  :)
> "Any acrobatic 
> maneuver" wasn't intended to mean 720 degree roll per second 
> rate or tail slides, or but just the basic 3 axis and 
> combinations.
"Any" means any.  Some planes can't even stall.
Jose
-- 
The monkey turns the crank and thinks he's making the music.
for Email, make the obvious change in the address.
DaveB
August 3rd 06, 02:06 AM
On Wed, 2 Aug 2006 09:11:14 -0500, "Jim Macklin"
> wrote:
>People were beginning to talk about all the different 
>maneuver that can be done in an airplane [in this case the 
>172, but this applies to all airplanes].  The OP asked about 
>"normal category" but even allowing for utility category, 
>the 172 is approved for very limited aerobatics.  The 
>specific allowed maneuvers are listed.
>
>Certainly, any airplane can perform any aerobatic maneuver, 
>since all the controls are present for all axis.
>
>But just as any camera can take portraits or porn, any 
>airplane will only do what the pilot can do.  If your name 
>is Bob Hoover  et al, you don't need to ask the question and 
>you probably can do these maneuvers.  But Joe Sixpack is 
>going to do several things...(a) bend the airplane (b) break 
>the airplane (c) wish he had a quick jettison door (d) wish 
>he had a parachute and (e) die.
>
>
>Simple rule,  The Law of Gravity has no exceptions or 
>appeals.
>
>
>
>-- 
>James H. Macklin
>ATP,CFI,A&P
>
>"Bob Moore" > wrote in message 
. 121...
>| Jim Macklin wrote
>|
>| > (5) Model 172L (1972 model)
>| > "This airplane must be operated in compliance with the
>| > operating limitations as stated in the form of placards,
>| > markings, and manuals:
>|
>| Yeah Jim, and we all MUST comply with all highway speed 
>limits,
>| even when they were 55 mph.  Hell...my speedometer even 
>had a
>| big red mark at 55 mph.
>|
>| A lot of those placards, markings, and manual limits are 
>just
>| because the manufacturer did not want to spend the time 
>and
>| money in order to seek certification for a particular 
>item.
>|
>| Such is the case of the "no slips with flaps" contained in 
>the
>| manual for a lot of the C-172s.
>|
>| Bob Moore 
>
>
I will be flying a 172 in the morning, I will roll it and report the
results.
Best
Daveb
Klein
August 3rd 06, 05:37 AM
On Wed, 02 Aug 2006 21:26:48 +0200, Stefan >
wrote:
>Jim Macklin schrieb:
>> You have to have "macros" to take porn?  "Any acrobatic 
>> maneuver" wasn't intended to mean 720 degree roll per second 
>> rate or tail slides, or but just the basic 3 axis and 
>> combinations.
>
>To me, "any" means "any". If you mean "some", then write "some". (Just 
>as stupid as top posting.)
>
>BTW, even your "basic" is wrong. Some airplanes cannot be rolled because 
>they have too little aileron authority while inverted. (Which means that 
>you can roll them to inverted, but not roll them back to upright again.)
I've always wondered what would happen if you got upside down due to a
strong vortex in a Mitsubishi MU-2.  These airplanes do not have
ailerons for roll control but instead have spoilers.  But if you don't
have spoilers on both sides of the wing (do they or not??) then how
would they operate inverted?   There used to be a MU-2 owner that
posted here occassionally.  Is he still around?
Klein
Jim Macklin
August 3rd 06, 06:03 AM
All airplanes can stall, even the stall proof airplanes. 
maybe the cargo shifts, maybe something happens, maybe the 
A&P mis-rigs the elevator or the stop breaks.  Trust me, all 
airplanes can stall.
"Jose" > wrote in message 
 t...
|> You have to have "macros" to take porn?
|
| Depends.  :)
|
| > "Any acrobatic
| > maneuver" wasn't intended to mean 720 degree roll per 
second
| > rate or tail slides, or but just the basic 3 axis and
| > combinations.
|
| "Any" means any.  Some planes can't even stall.
|
| Jose
| -- 
| The monkey turns the crank and thinks he's making the 
music.
| for Email, make the obvious change in the address.
Jose[_1_]
August 3rd 06, 06:36 AM
> All airplanes can stall, even the stall proof airplanes. 
> maybe the cargo shifts, maybe something happens, maybe the 
> A&P mis-rigs the elevator or the stop breaks.
I like the "maybe something happens" method of stalling a plane.  I was 
(of course) referring to airplanes that have not broken, and are being 
flown deliberately into a maneuver.  Not all airplanes are capable of 
all maneuvers.
Jose
-- 
The monkey turns the crank and thinks he's making the music.
for Email, make the obvious change in the address.
Jim Carter[_1_]
August 3rd 06, 03:03 PM
"Not all airplanes are capable of <completing> all maneuvers."
Regards,
James A. (Jim) Carter
> -----Original Message-----
> From: Jose ]
> Posted At: Wednesday, August 02, 2006 23:37
> Posted To: rec.aviation.piloting
> Conversation: barrel roll in 172
> Subject: Re: barrel roll in 172
> 
> > All airplanes can stall, even the stall proof airplanes.
> > maybe the cargo shifts, maybe something happens, maybe the
> > A&P mis-rigs the elevator or the stop breaks.
> 
> I like the "maybe something happens" method of stalling a plane.  I
was
> (of course) referring to airplanes that have not broken, and are being
> flown deliberately into a maneuver.  Not all airplanes are capable of
> all maneuvers.
> 
> Jose
> --
> The monkey turns the crank and thinks he's making the music.
> for Email, make the obvious change in the address.
Jim Macklin
August 3rd 06, 03:11 PM
Investigators find cause of fatal Utah plane crash
BY MOLLY MCMILLIN
The Wichita Eagle
The National Transportation Safety Board indicated in a 
preliminary report Tuesday that the linkage on an 
experimental twin-engine plane that killed two test pilots, 
including Wichita State University graduate Nathan Forrest, 
was installed incorrectly.
The Spectrum 33 crashed July 25 during takeoff from Spanish 
Fork-Springville Airport at Spanish Fork, Utah. The NTSB 
report said the plane's linkage -- which helps control the 
plane -- was installed backward.
"It was connected in a manner that reversed the roll 
control," the report said.
Witnesses indicated the airplane entered a right roll almost 
immediately after takeoff and the right wingtip hit the 
ground. The airplane -- which was made from advanced 
composite materials -- was destroyed by the impact, but all 
major components were accounted for in the wreckage, the 
NTSB said.
Spectrum president Austin Blue told Aviation International 
News that the company will continue with the program. First 
flight of the next test plane, which will be designed to 
ensure that the controls cannot be rigged incorrectly, will 
occur sometime next year, Aviation International said.
Forrest, 25, was a former Olathe resident who graduated from 
WSU in 2003. Also killed in the crash was 53-year old Glenn 
Maben, Spectrum's director of flight operations.
Remember, always, control wheel left and say, as you look, 
right one is down and the left one is up, pull backwards and 
note not just that the stick moves, but that the elevator us 
up.  Then stick right, left one is down and the right one is 
up then stick full forward and again verify the elevator 
moved in the correct direction. If the pilot can't see the 
control surfaces, have somebody on the outside to verify the 
correct movement.  Always do this, particularly after any 
maintenance.  It is not rare.
Some check lists say FREE and CORRECT.
--------------------------------------------------------------------------------
"Jose" > wrote in message 
. ..
|> All airplanes can stall, even the stall proof airplanes.
| > maybe the cargo shifts, maybe something happens, maybe 
the
| > A&P mis-rigs the elevator or the stop breaks.
|
| I like the "maybe something happens" method of stalling a 
plane.  I was
| (of course) referring to airplanes that have not broken, 
and are being
| flown deliberately into a maneuver.  Not all airplanes are 
capable of
| all maneuvers.
|
| Jose
| -- 
| The monkey turns the crank and thinks he's making the 
music.
| for Email, make the obvious change in the address.
Jose[_1_]
August 3rd 06, 04:06 PM
> "Not all airplanes are capable of <completing> all maneuvers."
If it hasn't completed a maneuver, it hasn't done it.
Jose
-- 
The monkey turns the crank and thinks he's making the music.
for Email, make the obvious change in the address.
Jim Macklin
August 3rd 06, 06:47 PM
I competition or air combat, I'd agree.  But if an airplane 
can roll to 60 degree bank it can be held in the roll and it 
will become inverted and then because of the inertia 
continue back to upright.  If you stop inverted you will 
have problems because most engines will quit after a short 
while, you might have some reduced aileron control and you 
probably didn't hold forward elevator so you split S'd out 
and roll control was returned.  You just could not do a 
competition grade hesitation roll.
If a Pitts S-2 starts a snap roll and the prop breaks off 
the hub, does that mean a Pitts S-2 can't do a snap roll? 
And if a Cessna 172 does a barrel roll, does that mean that 
all Cessna 172 PILOTS are capable of doing barrel rolls?
-- 
James H. Macklin
ATP,CFI,A&P
-- 
The people think the Constitution protects their rights;
But government sees it as an obstacle to be overcome.
 some support 
http://www.usdoj.gov/olc/secondamendment2.htm
See http://www.fija.org/ more about your rights and duties.
"Jose" > wrote in message 
 ...
|> "Not all airplanes are capable of <completing> all 
maneuvers."
|
| If it hasn't completed a maneuver, it hasn't done it.
|
| Jose
| -- 
| The monkey turns the crank and thinks he's making the 
music.
| for Email, make the obvious change in the address.
Jim Macklin
August 3rd 06, 06:58 PM
That's good, but I've heard of one case where the ailerons 
moved together up and down, not differentially.  Direct lift 
control, but is right up or down?  I don't that airplane 
actual tried to take-off.
If you box the control you can check for full and 
unrestricted travel for elevator and ailerons as well as 
correct rigging.  I have seen wire bundles get loose and 
block control travel and you might see the ailerons move 
correctly, but you might not have full travel of the 
elevator.
This is a killer, take off with engine failure, you can have 
a good chance to land without any damage.  Have the controls 
locked, blocked or reversed and you're a passenger in a 
missile.  The WSU football team DC3 tried to take-off with 
the gust locks installed on the tail, a C310 in Tulsa back 
in the early 70s took off with the controls reversed and 
immediately rolled into a smoking fireball.  These are pilot 
error.  The mechanic made a mistake, but the pilot has to 
check and verify... FREE and CORRECT.  Test flying is any 
first flight after any work is done to the airplane, from a 
tire or oil change to a control replacement.
-- 
James H. Macklin
ATP,CFI,A&P
"T o d d P a t t i s t" > wrote 
in message 
...
| "Jim Macklin" > 
wrote:
|
| >Remember, always, control wheel left and say, as you 
look,
| >right one is down and the left one is up, pull backwards 
and
| >note not just that the stick moves, but that the elevator 
us
| >up.  Then stick right, left one is down and the right one 
is
| >up then stick full forward and again verify the elevator
| >moved in the correct direction.
|
| Grab stick (or yoke for those unfortunates who have them)
| and stick your thumb up. Thumb should point towards the up
| control as you move stick.  Stick right, thumb points 
right,
| right aileron up.  Stick back, thumb points back, elevator
| up.  Simple to do, simple to remember.
|
|
| >Always do this, particularly after any
| >maintenance.  It is not rare.
|
| I've heard of several of these accidents, and was there 
when
| one was caught after maintenance (cables reversed).
|
| -- 
| Do not spin this aircraft. If the aircraft does enter a 
spin it will return to earth without further attention on 
the part of the aeronaut.
|
| (first handbook issued with the Curtis-Wright flyer)
Stefan
August 3rd 06, 07:46 PM
Jim Macklin wrote:
> But if an airplane 
> can roll to 60 degree bank it can be held in the roll and it 
> will become inverted and then because of the inertia 
> continue back to upright.
Not necessarily, and certainly not because of the inertia.
> If you stop inverted you will 
> have problems because most engines will quit after a short 
> while, you might have some reduced aileron control and you 
> probably didn't hold forward elevator so you split S'd out 
> and roll control was returned.
Or more likely, if done accidentally ("didn't hold forward elevator"), 
the airplane broke because of overload.
You should cease to spread dangerous wisdom about things you don't 
understand. (As well as cease to top post.)
Stefan
(Removed PED, because this isn't.)
Jim Macklin
August 3rd 06, 09:00 PM
I think Bill Gates like top posting, why should I change to 
satisfy you?
Perhaps you don't know what you're talking about either?
-- 
James H. Macklin
ATP,CFI,A&P
"Stefan" > wrote in message 
 ...
| Jim Macklin wrote:
|
| > But if an airplane
| > can roll to 60 degree bank it can be held in the roll 
and it
| > will become inverted and then because of the inertia
| > continue back to upright.
|
| Not necessarily, and certainly not because of the inertia.
|
| > If you stop inverted you will
| > have problems because most engines will quit after a 
short
| > while, you might have some reduced aileron control and 
you
| > probably didn't hold forward elevator so you split S'd 
out
| > and roll control was returned.
|
| Or more likely, if done accidentally ("didn't hold forward 
elevator"),
| the airplane broke because of overload.
|
| You should cease to spread dangerous wisdom about things 
you don't
| understand. (As well as cease to top post.)
|
| Stefan
| (Removed PED, because this isn't.)
Jose[_1_]
August 4th 06, 01:28 AM
> But if an airplane 
> can roll to 60 degree bank it can be held in the roll and it 
> will become inverted and then because of the inertia 
> continue back to upright.
By the time that happens, the nose may well be pointing down.  You'd 
need to push, and you might not have enough elevator authority to keep 
the nose on the horizon.  I don't know; I never did it in a 172.  I can 
certainly imagine other planes that don't have enough authority to keep 
it going.
> If a Pitts S-2 starts a snap roll and the prop breaks off 
> the hub, does that mean a Pitts S-2 can't do a snap roll?
If it comes off every time, yes.
-- 
The monkey turns the crank and thinks he's making the music.
for Email, make the obvious change in the address.
Dave Doe
August 5th 06, 08:23 AM
In article <l4sAg.84945$ZW3.9567@dukeread04>, p51mustang[threeX12]
@xxxhotmail.calm says...
> I think Bill Gates like top posting, why should I change to 
> satisfy you?
follow
to
hard
very
thread
the
makes
It
-- 
Duncan
Anno v. Heimburg
August 5th 06, 10:23 AM
Jim Macklin wrote:
> I think Bill Gates like top posting, why should I change to
> satisfy you?
A. Because it makes the thread hard to follow.
Q. Why is top posting frowned upon?
And what does Bill Gates have to do with that?
Matt Whiting
August 5th 06, 03:17 PM
Anno v. Heimburg wrote:
> Jim Macklin wrote:
> 
> 
>>I think Bill Gates like top posting, why should I change to
>>satisfy you?
> 
> 
> A. Because it makes the thread hard to follow.
> Q. Why is top posting frowned upon?
> 
> And what does Bill Gates have to do with that?
He's dyslexic.
Matt
Dylan Smith
August 8th 06, 02:08 PM
On 2006-08-05, Anno v. Heimburg > wrote:
> Jim Macklin wrote:
>
>> I think Bill Gates like top posting, why should I change to
>> satisfy you?
>
> A. Because it makes the thread hard to follow.
> Q. Why is top posting frowned upon?
Also, interleaved quoting (AND trimming quotes) is called netiquette -
the manners of Usenet. Transplanted to real life, "I think Bill Gates
like top posting, why should I change to satisfy you?" could become:
"I think the airlines like straight in approaches. Why should I enter
the pattern on a 45 to downwind just to satisfy you?"
"It's too much effort to wait three seconds to hold the door open for
the person following. Why should I wait three seconds just to satisfy
them?"
"Why should I say please and thank you? Some _insert rich person here_
gets by quite OK being extremely rude, so why should I change to satisfy
you?"
"Why should I move over to the right lane? Why should I leave my
comfortable rolling roadblock position just to satisfy you?"
Additionally, top posting costs people money. Top posters usually don't
trim their quoted material which can get quite long after a while. Those
reading Usenet when they are passing time in the airport, using their
cell phone, have to pay per kilobyte.
-- 
Yes, the Reply-To email address is valid.
Oolite-Linux: an Elite tribute: http://oolite-linux.berlios.de
Jose[_1_]
August 8th 06, 04:10 PM
> Additionally, top posting costs people money. Top posters usually don't
> trim their quoted material which can get quite long after a while. Those
> reading Usenet when they are passing time in the airport, using their
> cell phone, have to pay per kilobyte.
That's one place where I disagree - top posting saves money.
Although there may be a correlation between top posters and post 
trimming, it is the post non-trimming that costs money (to others), not 
the top posting.  Actually, top posting saves money for those who, after 
reading your comments, don't need to read what you were referring to 
(because they remember it), and therefore don't need to download it KB 
by KB.  It's available however for those who need a reminder.  For a 
bottom posted message, one must download (often repeatededly) a message 
one has already read (or at least parts of it) before getting to =any= 
new stuff; that is wasteful of costly KB.
Sometimes top posting is good, sometimes bottom posting is good.
Usually interleaving is best.  But there are never any absolutes.
Jose
-- 
The monkey turns the crank and thinks he's making the music.
for Email, make the obvious change in the address.
Dylan Smith
August 18th 06, 11:26 AM
On 2006-08-08, Jose > wrote:
> That's one place where I disagree - top posting saves money.
>
> Although there may be a correlation between top posters and post 
> trimming, it is the post non-trimming that costs money (to others), not 
> the top posting.  Actually, top posting saves money for those who, after 
> reading your comments, don't need to read what you were referring to 
> (because they remember it), and therefore don't need to download it KB 
> by KB. 
News readers don't work like that unfortunately. When you select an
article, the reader downloads the *whole* article, not just the bits of
it you are reading. Therefore, a top post with an untrimmed set of
quotes (usually, when top posters reply to top posters, you get an
enormously long history of quoted material at the bottom). Unless the
top poster trims the quoted material (which almost none of them do), you
end up downloading their 5 line comment along with 300+ lines of quotes.
The only occasion where someone reading Usenet would only download a bit
of the article they are reading is if they are reading Usenet over an
ssh connection to a remote server. However, the latency over GPRS is so
bad, this is quite painful - so anyone reading Usenet using a mobile
device will almost certainly use a news reader on their mobile device
rather than an ssh connection to a remote system.
-- 
Yes, the Reply-To email address is valid.
Oolite-Linux: an Elite tribute: http://oolite-linux.berlios.de
Jose[_1_]
August 18th 06, 04:46 PM
> News readers don't work like that unfortunately. When you select an
> article, the reader downloads the *whole* article, not just the bits of
> it you are reading.
This is not true for all software that accesses Usenet.  My palm VIIx 
(rest in peace) did it a K at a time.  My cell phone does the same, but 
even slower.  (it's a perfectly awful way to read Usenet, so I don't do 
it, but that's irrelevant).
> Therefore, a top post with an untrimmed set of
> quotes (usually, when top posters reply to top posters, you get an
> enormously long history of quoted material at the bottom)
Then your objection is =not= to top posting, but to non-trimming. 
Non-trimming is more painful in a bottom posted article - at least with 
a top posted article, once I come to the end of the original material, I 
can move on.
While your association of top posters with non-trimmers may be valid, it 
is irrelevant.  I've seen many bottom posters who add five lines to a 
300+ line quote (and far too many nested quoting that ends up being 300 
lines repeated for the most part post after post - supposedly good 
netiquette taken to the extreme - feh!)
Jose
-- 
The monkey turns the crank and thinks he's making the music.
for Email, make the obvious change in the address.
Roger[_4_]
August 18th 06, 10:24 PM
On Fri, 18 Aug 2006 09:26:27 -0000, Dylan Smith
> wrote:
>On 2006-08-08, Jose > wrote:
>> That's one place where I disagree - top posting saves money.
>>
>> Although there may be a correlation between top posters and post 
>> trimming, it is the post non-trimming that costs money (to others), not 
>> the top posting.  Actually, top posting saves money for those who, after 
>> reading your comments, don't need to read what you were referring to 
>> (because they remember it), and therefore don't need to download it KB 
>> by KB. 
>
>News readers don't work like that unfortunately. When you select an
>article, the reader downloads the *whole* article, not just the bits of
>it you are reading. Therefore, a top post with an untrimmed set of
>quotes (usually, when top posters reply to top posters, you get an
>enormously long history of quoted material at the bottom). Unless the
>top poster trims the quoted material (which almost none of them do), you
>end up downloading their 5 line comment along with 300+ lines of quotes.
>
>The only occasion where someone reading Usenet would only download a bit
>of the article they are reading is if they are reading Usenet over an
>ssh connection to a remote server. However, the latency over GPRS is so
>bad, this is quite painful - so anyone reading Usenet using a mobile
>device will almost certainly use a news reader on their mobile device
>rather than an ssh connection to a remote system.
Bottom posters do the same thing<:-))
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
Anno v. Heimburg
August 19th 06, 11:39 AM
Roger wrote:
>>> Although there may be a correlation between top posters and post
>>> trimming, it is the post non-trimming that costs money (to others), not
>>> the top posting. 
> Bottom posters do the same thing<:-))
That is exactly what the Grand-Grand-Parent said.
Roger[_4_]
August 20th 06, 05:11 AM
On Sat, 19 Aug 2006 11:39:52 +0200, "Anno v. Heimburg"
> wrote:
>Roger wrote:
>>>> Although there may be a correlation between top posters and post
>>>> trimming, it is the post non-trimming that costs money (to others), not
>>>> the top posting. 
>> Bottom posters do the same thing<:-))
>
>That is exactly what the Grand-Grand-Parent said.
Hey! What gives?  You trimmed off most of the post to which I was
refering.  Without it the rest just seems to lose meaning. <:-))
 
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com
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