Glider vs. Power Pattern Bank Angle?

[Jim Vincent]

In power, they're taught to fly patterns with very little bank angle, whereas
in gliders we're taught to bank at about 45 degrees or so. I well understand
the rationale for banking steeply in gliders, but why are power pilots taught
to do shallow turns?

TIA for the explanation.

Jim Vincent
CFIG
N483SZ

[BTIZ]

standard rate turns for most light general aviation is about 15 degrees of
bank... up to 30 degrees is considered the norm for power aircraft..

gliders fly closer in and tighter patterns.. so 45 degrees makes more
since.. can't say I've paid much attention to estimate the bank angle...
granted I fly the tow plane (Pawnee) in the same ground track pattern and
use 45 degrees of bank..

BT

"Jim Vincent" > wrote in message
...
> In power, they're taught to fly patterns with very little bank angle,
whereas
> in gliders we're taught to bank at about 45 degrees or so. I well
understand
> the rationale for banking steeply in gliders, but why are power pilots
taught
> to do shallow turns?
>
> TIA for the explanation.
>
> Jim Vincent
> CFIG
> N483SZ
>

[Tom Seim]

(Jim Vincent) wrote in message >...
> In power, they're taught to fly patterns with very little bank angle, whereas
> in gliders we're taught to bank at about 45 degrees or so. I well understand
> the rationale for banking steeply in gliders, but why are power pilots taught
> to do shallow turns?

The reason is, actually, pretty simple: power planes have god-awfull
visibility; if you bank too steeply you lose visual contact with a key
part of the pattern. This is something to keep in mind while flying in
the vacinity of power planes: if you can't see the cockpit, they can't
see you. In general, the best policy is to assume that they can't see
you and to act accordingly.

Tom Seim
Richland, WA

[Bruce Greeff]

Tom Seim wrote:
> (Jim Vincent) wrote in message >...
>
>>In power, they're taught to fly patterns with very little bank angle, whereas
>>in gliders we're taught to bank at about 45 degrees or so. I well understand
>>the rationale for banking steeply in gliders, but why are power pilots taught
>>to do shallow turns?
>
>
> The reason is, actually, pretty simple: power planes have god-awfull
> visibility; if you bank too steeply you lose visual contact with a key
> part of the pattern. This is something to keep in mind while flying in
> the vacinity of power planes: if you can't see the cockpit, they can't
> see you. In general, the best policy is to assume that they can't see
> you and to act accordingly.
>
> Tom Seim
> Richland, WA
More to the point - most of the time they will not have seen you, even if you
can see the whites of their eyes. Power pilots are not used to looking for
little slivers of white, and don't see what they don't expect. Even if they are
looking for you, which is often not the case.

We have a plague of low time power guys boring inexorably toward their selected
GPS turnpoint. In the far corner of the airfileld, after crossing three active
runways. Many of them are heads down watching the GPS, and don't even see the
winch or gliders. I am convinced some of them never see the airport they are
turning over...

That said I have also had a couple of them see me when I can't find their C172
sized lump. Can be embarassing to realise how easily you can miss something that
big, even when you know it is near, and even the general direction.

[Jim Vincent]

>The reason is, actually, pretty simple: power planes have god-awfull
>visibility; if you bank too steeply you lose visual contact with a key
>part of the pattern.

Tom, that makes sense to me for a high wing plane, but not for a low wing
plane. My friend had been taught never to bank too much in the pattern because
of the stall risk, I think. Yet us glider guiders are taught exactly the
opposite. Maybe since we fly the pattern so much closer to stall speed?


Jim Vincent
CFIG
N483SZ

[Brian Case]

2 more reasons for the shallow bank turns in power aircraft.

One Valid reason is that many power pilot carry passengers and it is
just more comfortable (less Scary) for the passangers to make
shallower turns.

Second, unfortunatly some of the procedures for making large patterns
with Power have trickled down from the Military and Airlines and have
started to be taught as standard for small single engine aircraft.
While these procedures are appropriate and the safest way to operate
Larger Turbine aircraft it is simply not applicable and can be
dangerous to operate small single engine aircraft this way.

I teach that a 30 degree bank turn should be typical (Vary as
appropriate) for turns in the Pattern for power aircraft This is a
good compromise for comfortable turns and reasonably small pattern
size.

Interestingly Many Pilots (Instructors included) don't seem to realize
that many (not all) aircraft actually are much harder to stall in a
steep turn than a shallow turn. This is because unless the CG is near
or past the aft CG Limit the elevator does not have enough power to
hold the turn and stall the wing. This is somewhat supported by fact
that most stall spin accidents are not initated from a steep turn but
rather from shallow skidded turns. Generally it is actually safer to
use a steeper turn.


Brian
CFIIG/ASEL

(Jim Vincent) wrote in message >...
> >The reason is, actually, pretty simple: power planes have god-awfull
> >visibility; if you bank too steeply you lose visual contact with a key
> >part of the pattern.
>
> Tom, that makes sense to me for a high wing plane, but not for a low wing
> plane. My friend had been taught never to bank too much in the pattern because
> of the stall risk, I think. Yet us glider guiders are taught exactly the
> opposite. Maybe since we fly the pattern so much closer to stall speed?
>
>
> Jim Vincent
> CFIG
> N483SZ
>

[Jim]

On 11 Jun 2004 05:47:17 -0700, (Brian Case) wrote:

<snip>

>Interestingly Many Pilots (Instructors included) don't seem to realize
>that many (not all) aircraft actually are much harder to stall in a
>steep turn than a shallow turn. This is because unless the CG is near
>or past the aft CG Limit the elevator does not have enough power to
>hold the turn and stall the wing. This is somewhat supported by fact
>that most stall spin accidents are not initated from a steep turn but
>rather from shallow skidded turns. Generally it is actually safer to
>use a steeper turn.
>

<snip>

I have experienced stall buffet at 60 degrees of bank in a thermal
in a DG-505, and I fly with a forward CG. Granted, stall buffet is
not yet a stall, and the DG's stall characteristics may be pretty
benign, but I no longer trust that a glider will be hard to stall in
steep turns. Because in a turn the inside wing is flying at a higher
AOA than the outside wing, the inside wing will likely stall, and
drop, before the outside wing. I understand that in some gliders
without the newer wing designs this inside wing stall may well be
followed an eye-blink later with an out-the-bottom spin entry.
The "Pooch" may be such a glider.

YMMV of course. I'm just glad to have noticed this.

[Jim]

On 11 Jun 2004 05:26:34 GMT, (Jim Vincent)
wrote:

>>The reason is, actually, pretty simple: power planes have god-awfull
>>visibility; if you bank too steeply you lose visual contact with a key
>>part of the pattern.
>
>Tom, that makes sense to me for a high wing plane, but not for a low wing
>plane. My friend had been taught never to bank too much in the pattern because
>of the stall risk, I think. Yet us glider guiders are taught exactly the
>opposite. Maybe since we fly the pattern so much closer to stall speed?
>
>
>Jim Vincent
>CFIG
>N483SZ


I think many instructors don't like to contemplate a student pilot in
a low, slow, steeply banked turn in an aircraft with low aspect
ratios - such as most simple, powered aircraft. Low aspect ratio
means relatively high drag, thus relatively greater airspeed decay, at
a given AOA, including the relatively high AOA likely in slow, steep
turns.

The argument I've heard for the safety of steeper bank angles is
that the pilot is less likely to make the anxiety-forced error of
thinking the aircraft can be hurried around its turn by the liberal
application of pro-turn rudder: a skidded turn which produces it own
pitch and bank effects that can lead to a stall/spin.

Gliders, with their higher aspect ratio wings, suffer less drag, thus
less airspeed loss, a a given AOA.

[Andy Durbin]

(Jim Vincent) wrote in message >...
> >The reason is, actually, pretty simple: power planes have god-awfull
> >visibility; if you bank too steeply you lose visual contact with a key
> >part of the pattern.
>
> Tom, that makes sense to me for a high wing plane, but not for a low wing
> plane. My friend had been taught never to bank too much in the pattern because
> of the stall risk, I think. Yet us glider guiders are taught exactly the
> opposite. Maybe since we fly the pattern so much closer to stall speed?
>
>
> Jim Vincent
> CFIG
> N483SZ
>

I never bank *too much* in airplanes. In the pattern I use at least 30
deg, more for a high wing with a green house because that gives a good
view into the turn.

The view into the turn varies greatly for high wing airplanes. In a
182 leaning forward gives tolerable vizibility. In an Aeronca Chief
you can't see into the turn at all. That's why competent pilots will
raise the wing before starting the turn.

I don't think I flew any power plane with the view into the turn as
bad as from the 2-33 back seat!

I don't believe visibility is the reason some airplane pilots use
shallow banks in the pattern. I'm also not convinced that gliders fly
closer to stall speed in the pattern. I think it's just that some
airplane pilots were taught by instructors that didn't know any
better.

Andy

[Skip Guimond]

The PTS for the SEL rating requires the demonstration of steep turns,
and this maneuver is flown on virtually every check ride. I believe
that the main reason for "gentle" turns is a cultural and training
issue. Power training almost always considers the passenger in the
aircraft--something which is normally not a major issue in soaring.

Frankly, most true passengers are not comfortable in bank angles
greater than 30 degrees. A second MAJOR issue is the continuing
training toward the instrument rating. In actual instrument
conditions turns are normally accomplished at "standard" rate--a
gentle bank. This provides less chance for the pilot to loose control
while flying only with reference to instruments.

An often heard comment from the CFI during the training of a
commercial student is that when he gets his first commercial job his
performance will be judged by the smoothness of his landings
(regardless of winds, etc) and not spilling the president's drink in
the back.

Just some thoughts--

Skip Guimond

[John H. Campbell]

> whereas in gliders we're taught to bank at about 45 degrees or so.

I don't think so. A "medium" turn of 30 deg. works well (gliders are
typically most roll stable near this value), is first introduced, best
rehearsed, most common (it's the famous optimum bank for "standard"
thermals), easiest to perform (Laws of Learning REPEIR, Levels of Learning
RUAC...) and gives the option to go both to a "shallow" bank of 15 deg. or a
"steep" bank of 45 deg. to adjust turn radius in progress if necessary
(maintaining good coordination and speed control) without going (at low
altitudes no less) near the parachute-wearing limit of 60 deg. or the
"abrupt..." condition of aerobatic flight. The FAA PTS does not recommend
any particular bank angle for the Landing Task, but it does define a Steep
turn Task in the Performance Maneuver Area of Operation as 45 +/-5 deg. If
that's your starting value for an ordinary turn in the pattern, how much
steeper (and more stressful) are you planning to go if your path is going
past the line of the runway?

[Michael]

(Jim Vincent) wrote
> In power, they're taught to fly patterns with very little bank angle, whereas
> in gliders we're taught to bank at about 45 degrees or so. I well understand
> the rationale for banking steeply in gliders, but why are power pilots taught
> to do shallow turns?

Mainly because the quality of power instruction is, on the whole,
dramatically worse than the quality of glider instruction. The
majority of power instructors are low time, inexperienced pilots who
have completed a training program that takes them from zero time to
instructor (single, multi, and instrument) in less than 300 hours.
They have been taught to fly wide, power-on patterns with stabilized
power-on approaches because this is what they will be doing in the
airlines (their eventual goal) and that's what they teach their
students because they don't know anything else.

Steep turns, especially at low speed, simply scare them. Therefore,
many of them tell students not to exceed 30 degrees of bank in the
pattern.

The power-off pattern, where you bring the power to idle at about
800-1000 ft AGL and abeam the touchdown point and continue to a
landing, was once the normal pattern in general aviation for all light
trainers. Of course in such a pattern your turns will be 30-45
degrees of bank, depending on wind and how many mistakes you make.
The trainers have not changed; in fact we're mostly flying the same
ones. However, today's instructors see this as an emergency
procedure, not a normal one, because it pushes their skill level.

Michael

[Tony Verhulst]

> ...instructor (single, multi, and instrument) in less than 300 hours.
> They have been taught to fly wide, power-on patterns with stabilized
> power-on approaches because this is what they will be doing in the
> airlines (their eventual goal) and that's what they teach their
> students because they don't know anything else.

No kidding! I freaked one out once during a BFR by slipping a Skylane on
short final.

Tony V

[Brian Case]

Jim > wrote in message >...
> On 11 Jun 2004 05:47:17 -0700, (Brian Case) wrote:
>
> <snip>
>
> >Interestingly Many Pilots (Instructors included) don't seem to realize
> >that many (not all) aircraft actually are much harder to stall in a
> >steep turn than a shallow turn. This is because unless the CG is near
> >or past the aft CG Limit the elevator does not have enough power to
> >hold the turn and stall the wing. This is somewhat supported by fact
> >that most stall spin accidents are not initated from a steep turn but
> >rather from shallow skidded turns. Generally it is actually safer to
> >use a steeper turn.
> >
>
> <snip>
>
> I have experienced stall buffet at 60 degrees of bank in a thermal
> in a DG-505, and I fly with a forward CG. Granted, stall buffet is
> not yet a stall, and the DG's stall characteristics may be pretty
> benign, but I no longer trust that a glider will be hard to stall in
> steep turns. Because in a turn the inside wing is flying at a higher
> AOA than the outside wing, the inside wing will likely stall, and
> drop, before the outside wing. I understand that in some gliders
> without the newer wing designs this inside wing stall may well be
> followed an eye-blink later with an out-the-bottom spin entry.
> The "Pooch" may be such a glider.
>
> YMMV of course. I'm just glad to have noticed this.

Granted Gliders probably are more likely to stall in a steep turn than
most power aircraft due to the long wings and the larger differences
in AoA from the inside to outside wing as you noted.

Brian

[Jack]

John H. Campbell wrote:

>> whereas in gliders we're taught to bank at about 45 degrees or so.
>
> I don't think so.

[multo snippo]

> ...how much steeper (and more stressful) are you planning to go
> if your path is going past the line of the runway?

I guess I'd use as much bank as I need, whether 60 or 90, and whatever airspeed
and wing loading it takes to do the job, since I don't expect to be able to make
a go around. How about you? If I don't like the situation, I'll simply avoid
repeating it. Of course I have the advantage of having begun flying when the
laws of physics were considered to be useful rather than something of which to
be unduly terrified.

When the FAA again change the PTS, this time to something like a steep turn = 35
degrees, where will we be? Sixty degrees is a steep turn: 45 degrees is merely
an inappropriate pattern planning parameter. I generally fly my patterns fairly
close-in at around 20 to 25 degrees of bank. I mean, really, it's a glider after
all, not an F-105. On the other hand, if bank angle equals stress, perhaps we
should be advocating something other than flying gliders for more folks.

And Michael's following post:

> ...the quality of power instruction is, on the whole,
> dramatically worse than the quality of glider instruction.
> The majority of power instructors...teach their students
> (wide, shallow bank patterns) because they don't know
> anything else.

hits the nail on the head. Today's CFI-ASEL must teach wide shallow bank
patterns because that's what everyone uses, and to fly a proper pattern has
become nearly impossible when their are other aircraft in the pattern ahead, and
of course the ones behind won't know where to look for you and seem unaware of
the many possibilities.

Now if it would just stop raining, I could go out and soar instead of taking my
frustration out on good ol' John H., who is, after all, just doing what he
thinks is right.



Jack

[ADP]

If you can't pull off power, abeam the numbers, between 500 ft and 1000 ft
above the airport and make a landing
without adding or using power, you ought not to be flying light aircraft.
(Single engine < 5000#)

Allan

">>
> The power-off pattern, where you bring the power to idle at about
> 800-1000 ft AGL and abeam the touchdown point and continue to a
> landing, was once the normal pattern in general aviation for all light
> trainers. Of course in such a pattern your turns will be 30-45
> degrees of bank, depending on wind and how many mistakes you make.
> The trainers have not changed; in fact we're mostly flying the same
> ones. However, today's instructors see this as an emergency
> procedure, not a normal one, because it pushes their skill level.
>
> Michael

[Vaughn]

"Michael" > wrote in message
om...
> (Jim Vincent) wrote
>
> Mainly because the quality of power instruction is, on the whole,
> dramatically worse than the quality of glider instruction. The
> majority of power instructors are low time, inexperienced pilots who
> have completed a training program that takes them from zero time to
> instructor (single, multi, and instrument) in less than 300 hours.
> They have been taught to fly wide, power-on patterns with stabilized
> power-on approaches because this is what they will be doing in the
> airlines (their eventual goal) and that's what they teach their
> students because they don't know anything else.

Actually there are many reasons, some of them may be found in the SEL PTS.
Another is that airports with lots of light aircraft training end up with huge
"follow the leader" patterns.

> Steep turns, especially at low speed, simply scare them. Therefore,
> many of them tell students not to exceed 30 degrees of bank in the
> pattern.

After several years of soaring, I recently decided to transition to power.
I have had that poor guy squirming in his seat and grabbing for the controls
more than once doing things that I considered perfectly normal, including tight
turns in the pattern.
>
> The power-off pattern, where you bring the power to idle at about
> 800-1000 ft AGL and abeam the touchdown point and continue to a
> landing, was once the normal pattern in general aviation for all light
> trainers. Of course in such a pattern your turns will be 30-45
> degrees of bank, depending on wind and how many mistakes you make.
> The trainers have not changed; in fact we're mostly flying the same
> ones. However, today's instructors see this as an emergency
> procedure, not a normal one, because it pushes their skill level.


Come to think of it, the FAA has changed landings since our trainers were
designed. Vaguely 20 years ago, there was a sea change in the way landing
technique was taught because someone in the FAA decided that normal landings
would be accomplished with full flaps. The normal technique that is taught
these days (at least in a Cezzna) is the first notch on downwind, second notch
on base and full flaps on final. This adds so much drag that you either do a
high (and or tight) pattern or you must drag the thing around the pattern with
power. Guess which one they usually teach?


Vaughn


>
> Michael

[Vaughn]

"John H. Campbell" > wrote in message
...
> > whereas in gliders we're taught to bank at about 45 degrees or so.
>
> I don't think so. A "medium" turn of 30 deg. works well (gliders are
> typically most roll stable near this value), is first introduced, best
> rehearsed, most common (it's the famous optimum bank for "standard"
> thermals), easiest to perform (Laws of Learning REPEIR, Levels of Learning
> RUAC...) and gives the option to go both to a "shallow" bank of 15 deg. or a
> "steep" bank of 45 deg. to adjust turn radius in progress if necessary
> (maintaining good coordination and speed control) without going (at low
> altitudes no less) near the parachute-wearing limit of 60 deg. or the
> "abrupt..." condition of aerobatic flight. The FAA PTS does not recommend
> any particular bank angle for the Landing Task, but it does define a Steep
> turn Task in the Performance Maneuver Area of Operation as 45 +/-5 deg. If
> that's your starting value for an ordinary turn in the pattern, how much
> steeper (and more stressful) are you planning to go if your path is going
> past the line of the runway?

Thanks for this, I was starting to think I had been taught (and been
teaching) wrong.

Vaughn


>
>
>
>

[Pete Reinhart]

Tony,
Me too!
Cheers!
"Tony Verhulst" > wrote in message
...
>
> > ...instructor (single, multi, and instrument) in less than 300 hours.
> > They have been taught to fly wide, power-on patterns with stabilized
> > power-on approaches because this is what they will be doing in the
> > airlines (their eventual goal) and that's what they teach their
> > students because they don't know anything else.
>
> No kidding! I freaked one out once during a BFR by slipping a Skylane on
> short final.
>
> Tony V
>

[Mike Lindsay]

In article >, Tom Seim
> writes
(Jim Vincent) wrote in message news:<20040610165940.0224
>...
>> In power, they're taught to fly patterns with very little bank angle, whereas
>> in gliders we're taught to bank at about 45 degrees or so. I well understand
>> the rationale for banking steeply in gliders, but why are power pilots taught
>> to do shallow turns?
>
>The reason is, actually, pretty simple: power planes have god-awfull
>visibility; if you bank too steeply you lose visual contact with a key
>part of the pattern. This is something to keep in mind while flying in
>the vacinity of power planes: if you can't see the cockpit, they can't
>see you. In general, the best policy is to assume that they can't see
>you and to act accordingly.
>
>Tom Seim
>Richland, WA

Not ALL power planes. Our club has 2 Robin D400 Avions for tugs and you
get a very good view out of them. The same goes for the Rallaye we used
to have.

I hesitate to say this, but maybe its just US aircraft?

--
Mike Lindsay

[Bruce Hoult]

In article >,
Jim > wrote:

> I have experienced stall buffet at 60 degrees of bank in a thermal
> in a DG-505, and I fly with a forward CG. Granted, stall buffet is
> not yet a stall, and the DG's stall characteristics may be pretty
> benign, but I no longer trust that a glider will be hard to stall in
> steep turns.

I haven't flown a 505, but I've tried a DG-1000, and it has a *lot* of
available elevator power compared to most recent training gliders. The
thing can not only be held so deep into a stall that it will virtually
always drop one wing or the other, it can be flick rolled! (and the POH
permits that, with the 18m tips on)

But it gave so much notice that you were dicing with the stall that I
wouldn't be at all worried thermalling it slow.

-- Bruce

[Michael]

"Vaughn" > wrote
> > that's what they teach their
> > students because they don't know anything else.
>
> Actually there are many reasons, some of them may be found in the SEL PTS.

True. I oversimplified. Far be it from me to suggest that the FAA
isn't a big part of the problem - it is. Some of the stuff in the PTS
is garbage. It's getting better again, though. Real slow flight is
back - for several years, slow flight was redefined as 1.2 Vso. Steep
turns were redefined to 45 degrees and I see no hope of change there.
The 180 to a landing is back in the commercial PTS though, and that's
a plus.

> Another is that airports with lots of light aircraft training end up
> with huge "follow the leader" patterns.

Ah, yes - the "everybody is doing it" argument. Actually, I do
understand - sometimes the safest thing to do is just grit your teeth
and do it the same way everyone else does it. Only when I learned to
fly I was taught that when the pattern is strung out that way, you
hold your altitude until you reach power-off gliding distance of the
field, then reduce to idle and glide in.

> Come to think of it, the FAA has changed landings since our trainers were
> designed. Vaguely 20 years ago, there was a sea change in the way landing
> technique was taught because someone in the FAA decided that normal landings
> would be accomplished with full flaps.

Well, that makes sense to me. As far as I'm concerned, the normal
landing is made with full flaps. Anything less is a special case - a
reduced-workload training exercise for an early presolo student,
strong crosswind in an airplane where flaps reduce rudder/elevator
authority, that kind of deal. Otherwise, why accept the higher
touchdown speed with its attendant risks, extra wear on tires and
brakes, etc?

> The normal technique that is taught
> these days (at least in a Cezzna) is the first notch on downwind, second notch
> on base and full flaps on final.

And there's the problem. What's wrong with a clean downwind, two
notches on base to adjust the glide, and then the rest on final when
it looks right? I was taught to land that way. In fact, I was taught
to land a Cessna by bringing the power to idle abeam the numbers and
adding flaps as necessary to control glideslope. Might have had
something to do with the fact that my primary instructor flew gliders
too...

> This adds so much drag that you either do a
> high (and or tight) pattern or you must drag the thing around the pattern with
> power. Guess which one they usually teach?

Right - because that's all they know. They really don't know enough
about flying a tight high pattern to teach it.

In a multiengine turbine airplane, what they teach is actually the
right thing to do. Those engines take time to spool up, so you dirty
the plane up, keep the engines spooled up, and for a go-around you
clean up the plane - this way you can get a climb going before the
engines are fully spooled up.

The problem is, we're flying light piston airplanes.

Michael

[Gldcomp]

> > Because in a turn the inside wing is flying at a higher
> > AOA than the outside wing, the inside wing will likely stall, and
> > drop, before the outside wing. I understand that in some gliders
> > without the newer wing designs this inside wing stall may well be
> > followed an eye-blink later with an out-the-bottom spin entry.
Actually, this is a common misconception, but there is no such thing as an
inside wing stall on any turn, unless it is a very shallow turn in a
pre-stall configuration, and the pilot suddenly applies aileron opposite the
turn, in which case the inside wing will stall first.

This is the common situation when pilots are trying to prolong the glide by
holding the nose high and doing skidding turns.
The opposite aileron is the only way to prevent the wings from banking more
(which is what the pilot is erroneously trying to prevent).
That is why, it is repeated so many times, by so many people, so many books,
that you can't spin from a steep turn, only from a shallow turn.

> > The "Pooch" may be such a glider.

I don't know where you got this from. The Puchacz has absolutely marvelous
characteristics.
I spun and instructed in them for years.

[Bill Daniels]

"Gldcomp" > wrote in message
om...

> That is why, it is repeated so many times, by so many people, so many
books,
> that you can't spin from a steep turn, only from a shallow turn.

This is an overstatement. While it is certainly more difficult to spin from
a steep turn, spins are possible from any attitude depending mostly on the
CG position and the general susceptibility of the glider in question to
spins.

I have flown several gliders which would spin from an accelerated stall in a
near 90 digree bank. Whether these gliders spin "over the top" or out the
bottom" depends on the rudder input at the moment of the stall. It's an "E"
ticket ride to be sure.

Bill Daniels

[Kirk Stant]

(Brian Case) wrote in message >...

> Second, unfortunatly some of the procedures for making large patterns
> with Power have trickled down from the Military and Airlines and have
> started to be taught as standard for small single engine aircraft.

Please leave the military out of this argument - all military training
I've been through teaches nice appropriately steep turns in the
pattern. In fighter-type jets (which includes most trainers, such as
T-37s and T-38s) an overhead break will start with a nice steep
(>60degree) break turn to downwind, and the continuous 180 degree turn
from downwind to final (which I still love to do in my LS6, from a
nice tight pattern following a low pass) is commonly flown at 30-45
degrees of bank, as required to keep it tight and roll out on final.

On the other hand, civilian light plane training (in the big schools)
is seemingly all geared towards IFR and airline prep - so the emphasis
on low bank angle, stabilized power-on approaches, etc.

Hideous airmanship in a Cezzna or Piper, IMHO! But my at least my
coffee doesn't get spilled when I'm travelling (it no longer counts as
flying) in a Boeing or Airbus tubular extrusion.

Kirk

[Bert Willing]

And as a general statement, it is completely bull****.

There are a lot of gliders which don't have the elevator authority to stall
from a steep bank angle. However, there ARE gliders which can do that. Long
wings help on that, and flying in turblent air like rotors (where you
usually circle with decent bank angles) does help very well.

--
Bert Willing

ASW20 "TW"


"Gldcomp" > a écrit dans le message de
om...
> That is why, it is repeated so many times, by so many people, so many
books,
> that you can't spin from a steep turn, only from a shallow turn.
>

[Jim]

On Mon, 14 Jun 2004 22:57:59 GMT, "Gldcomp" >
wrote:

>> > Because in a turn the inside wing is flying at a higher
>> > AOA than the outside wing, the inside wing will likely stall, and
>> > drop, before the outside wing. I understand that in some gliders
>> > without the newer wing designs this inside wing stall may well be
>> > followed an eye-blink later with an out-the-bottom spin entry.
>Actually, this is a common misconception, but there is no such thing as an
>inside wing stall on any turn, unless it is a very shallow turn in a
>pre-stall configuration, and the pilot suddenly applies aileron opposite the
>turn, in which case the inside wing will stall first.

Wow. "... there is no such thing as an inside wing stall on any turn,
unless it is a very shallow turn ...". Maybe it's just me, but I
think I'll just continue to consider this sort of stall something to
be alert to. YMMV.

>
>This is the common situation when pilots are trying to prolong the glide by
>holding the nose high and doing skidding turns.
>The opposite aileron is the only way to prevent the wings from banking more
>(which is what the pilot is erroneously trying to prevent).
>That is why, it is repeated so many times, by so many people, so many books,
>that you can't spin from a steep turn, only from a shallow turn.
>
>> > The "Pooch" may be such a glider.
>
>I don't know where you got this from. The Puchacz has absolutely marvelous
>characteristics.
>I spun and instructed in them for years.
>

[Brian Case]

> Actually, this is a common misconception, but there is no such thing as an
> inside wing stall on any turn, unless it is a very shallow turn in a
> pre-stall configuration, and the pilot suddenly applies aileron opposite the
> turn, in which case the inside wing will stall first.
>

I had to think about this for a while. My thought process when
something like this:

If the AOA is the same on the inside and outside wing there will be no
tendency for the wing to stall one way or the other.

In a coordinated turn the AOA should be the same on the inside and
outside wing. This is obviously true in level flight and in 90degree
bank turn.

However in a 45 degree bank turn it is obvious that the inside wing
travels less distance than the outside wing in 360 degree turn, thus
it must be flying at a lower relative airspeed than the outside wing.

It turns out that this is what causes overbanking tendency. To
compensate for overbanking tendancy the aircraft must have short wings
and/or a lot of dihedral. Dihedrall effectivaly increases the wing
area of the inside wing so and increase in AOA is not required. If
there is not enought dihedral for the turn then the overbanking
tendancy must be compensated for by the ailerons which increase the
angle of attack of the inside wing. Thus you get an inside wing stall.
A 2-33 should demostrate this very will as it has a very large
overbanking tendancy.

[Brian Case]

> Actually, this is a common misconception, but there is no such thing as an
> inside wing stall on any turn, unless it is a very shallow turn in a
> pre-stall configuration, and the pilot suddenly applies aileron opposite the
> turn, in which case the inside wing will stall first.
>

Expanding on my previous thought process. Execesive Overbanking
tendancy may be the reason that some aircraft won't (or at least are
difficult to) stall the inside wing. The 2-33 for example the
overbanking tendancy is so bad that it may run out of aileron to hold
it in a constant bank turn at low speed. This requires the pilot
either lower the nose or apply opposite rudder to prevent the turn
from getting any steeper, both of which will lower the AOA on the
inside wing. If the pilot allows the bank to get steeper the airplane
runs out of elevator authority and the nose drops on its own
increasing the airspeed and also lowering the angle of attack.

As is almost always the case moveing the CG back will give the
airplane more elevator authority and a better change of being able to
stall the inside wing.