A dumb doubt on stalls

wrote in
ups.com:

snip


P.S. Bets are placed, at my flying club, how long it will take before
I get bored with that C150.



You are flying! How can that be boring? As much fun as the Rallye? No,
but not boring.

--
Marty Shapiro
Silicon Rallye Inc.

(remove SPAMNOT to email me)

Sorry, I've been attempting to emulate the mental processes
of a Democrat.


"Gary Drescher" wrote in message
. ..
| "Jim Macklin" wrote
in message
| news:Z6vmg.49402$ZW3.30156@dukeread04...
| "Matt Whiting" wrote:
| Jim Macklin wrote:
| No, do I need a credible reference?
|
| Only if you want us to believe you as what you are
saying goes against
| everything most of us have seen published in the
literature.
|
| I don't care what you believe.
|
| You're a CFI, so we care what your students are led to
believe.
|
| Maybe I just wanted a heated discussion to start,
|
| Uh, sure Jim. But there's been little heated discussion.
Several of us have
| just been patiently explaining to you an elementary aspect
of aviation.
|
| If the tail does not stall, to some degree, what tail
down
| force ceases to exist to maintain the nose up attitude?
|
| That's a perfectly reasonable question, and it's been
answered for you at
| least five times in this thread. (Hint: search for
"relative wind".) Each
| time, you've simply *ignored* the answer without even
*trying* to point out
| any flaw in it.
|
| Your approach to discussing aviation is the same as your
approach to
| discussing politics. In both domains, you're willing to
engage in debate *as
| long as it just rehashes material that's already familiar
to you*. But as
| soon as anyone raises an objection that you hadn't
previously considered,
| you just ignore it and retreat to familiar ground,
repeating the claims that
| the objection already defeated, making no attempt to
refute the objection.
|
| Unfortunately, that approach completely defeats the
purpose of rational
| discourse, because it renders your beliefs incorrigible.
Perversely, you're
| left with the illusion that you've sustained your
position; but the reality
| is that you merely went through the motions of rational
discourse until just
| before the point where a meaningful exchange of ideas
would begin.
|
| --Gary
|
|

wrote:
george wrote:
wrote:
Hi Marty,

Rallyes are really fun, I miss mine from time to time. :-(

Great short field performance especially the 885

I had an 880, good performance for just 100hp(not talking speed)
Was thinking about buying an 885 but with avgas prices about $11.5/ us
gallon and not much faster than an 880......nah, not a good idea.

I soloed in a 880.
Main impression was those bloody slats on crosscountries keeping me
awake :-)
we had a 880 bore in with 4 sob while they were overloaded and playing
silly games

george wrote:
wrote:
george wrote:
wrote:
Hi Marty,

Rallyes are really fun, I miss mine from time to time. :-(

Great short field performance especially the 885

I had an 880, good performance for just 100hp(not talking speed)
Was thinking about buying an 885 but with avgas prices about $11.5/ us
gallon and not much faster than an 880......nah, not a good idea.

I soloed in a 880.
Main impression was those bloody slats on crosscountries keeping me
awake :-)
we had a 880 bore in with 4 sob while they were overloaded and playing
silly games

Now you mention the slats.
Last May I had my biannual and since I didn't have a plane I had to
rent one.
I can tell you that Rallye habbits do not work well in a Grob 115( a
German tupperware plane).
The instructor had enough remarks about my handling.
As on the first landing.
-He, pay attention, you are about to going to stall.
-Hmm, No I'm not.....Oh sh*t this stupid thing has no slats.

-Kees

"Jim Macklin" wrote in message
news:BQBmg.49424$ZW3.24753@dukeread04...
Sorry, I've been attempting to emulate the mental processes
of a Democrat.

Putting aside the vacuous gibe, does that mean you now agree that your
account of stalls was incorrect? I'm genuinely concerned for the sake of
your students. If they were to believe you that an ordinary stall involves
stalling the tail, then they'd have reason to think that a tail stall isn't
a big deal. That would lead them to be less frightened than they should be
of circumstances that really can cause a tail stall (such as tail icing or a
too-forward CG).

--Gary

Maybe, I'm going to take a poll and see what I should do.

As far as my students go, they've been doing well for
decades. Many are or have been USAF, USN and some even hold
degrees as aeronautical engineers.


--
James H. Macklin
ATP,CFI,A&P

"Gary Drescher" wrote in message
...
| "Jim Macklin" wrote
in message
| news:BQBmg.49424$ZW3.24753@dukeread04...
| Sorry, I've been attempting to emulate the mental
processes
| of a Democrat.
|
| Putting aside the vacuous gibe, does that mean you now
agree that your
| account of stalls was incorrect? I'm genuinely concerned
for the sake of
| your students. If they were to believe you that an
ordinary stall involves
| stalling the tail, then they'd have reason to think that a
tail stall isn't
| a big deal. That would lead them to be less frightened
than they should be
| of circumstances that really can cause a tail stall (such
as tail icing or a
| too-forward CG).
|
| --Gary
|
|

circumstances that really can cause a tail stall (such as [...] a
too-forward CG).

Ding.

Obvious once I thought about it (duh!), but it had never occured to me
before, and nobody had ever mentioned it in my training. How far
further forward would the CG need to be to cause a tail stall in normal
flight attitudes?

Jose
--
The monkey turns the crank and thinks he's making the music.
for Email, make the obvious change in the address.

"Jose" wrote in message
news
circumstances that really can cause a tail stall (such as [...] a
too-forward CG).

Ding.

Obvious once I thought about it (duh!), but it had never occured to me
before, and nobody had ever mentioned it in my training. How far further
forward would the CG need to be to cause a tail stall in normal flight
attitudes?

Although I haven't done the calculation, I'd be surprised if a typical GA
plane could tail-stall at a normal in-flight angle of attack no matter how
far forward you had the CG (unless you were to tie some cinder blocks to the
nose gear or something). The danger would come during the landing flare, or
if you tried to do slow flight or stall practice, or if turbulence were to
abruptly increase the AoA.

--Gary

"Jim Macklin" wrote in message
news:zZTmg.49464$ZW3.45524@dukeread04...
Maybe, I'm going to take a poll and see what I should do.

As far as my students go, they've been doing well for
decades. Many are or have been USAF, USN and some even hold
degrees as aeronautical engineers.

Yes, I'd expect most of your students to survive the confusion--either
because they know better than to accept your model (try asking the AEs about
it), or because they don't happen to consider the ramifications I mentioned.

Still, there's no reason to impose the small but real danger that comes from
teaching a false, confusing model of stalls when a correct model is readily
available instead.

--Gary

James H. Macklin
ATP,CFI,A&P

"Gary Drescher" wrote in message
...
| "Jim Macklin" wrote
in message
| news:BQBmg.49424$ZW3.24753@dukeread04...
| Sorry, I've been attempting to emulate the mental
processes
| of a Democrat.
|
| Putting aside the vacuous gibe, does that mean you now
agree that your
| account of stalls was incorrect? I'm genuinely concerned
for the sake of
| your students. If they were to believe you that an
ordinary stall involves
| stalling the tail, then they'd have reason to think that a
tail stall isn't
| a big deal. That would lead them to be less frightened
than they should be
| of circumstances that really can cause a tail stall (such
as tail icing or a
| too-forward CG).
|
| --Gary
|
|

Did I ever say that I had taught any particular theory to
any student?

If an airplane was only a wing and there was no tail, would
a high speed computer monitoring angle of attack,
differential pressure and able to use spoilers, slats,
weight-shift, boundary layer control, etc be able to fly the
wing? Would it make a difference if the wing was straight
or swept?

If dimples make a golf ball fly further and stitches make a
baseball curve, why do airplanes have neither? Why do some
people think that space aliens built the pyramids or that
all the tall buildings were built with demolition charges so
the government could bring down the buildings in a phony
terrorist attack?

Lift varies with the square of the airspeed, at the same
angle of attack, double the speed and the lift increases by
four times. Assuming a linear change in lift with changes
in angle of attack, if the aircraft is slowed by 50% and the
angle of attack is increased to compensate, how much is
that? If a train leaves Boston at midnight headed for
Chicago and a Mexican crosses the border at the same time,
when will you hub caps be stolen in St. Louis?

If a student pilot departs an airport in Class B airspace
and flies 1,000 miles in Class A airspace before landing at
an airport in Class G airspace, is the student pilot in
violation of any regulation? Has any regulation been
violated? Did the flight leave Portland, OR and go to
Alaska? Was the student pilot just a passenger on an
airline?

Is Buffy the Vampire Slayer based on fact?



"Gary Drescher" wrote in message
...
| "Jim Macklin" wrote
in message
| news:zZTmg.49464$ZW3.45524@dukeread04...
| Maybe, I'm going to take a poll and see what I should
do.
|
| As far as my students go, they've been doing well for
| decades. Many are or have been USAF, USN and some even
hold
| degrees as aeronautical engineers.
|
| Yes, I'd expect most of your students to survive the
confusion--either
| because they know better than to accept your model (try
asking the AEs about
| it), or because they don't happen to consider the
ramifications I mentioned.
|
| Still, there's no reason to impose the small but real
danger that comes from
| teaching a false, confusing model of stalls when a correct
model is readily
| available instead.
|
| --Gary
|
| James H. Macklin
| ATP,CFI,A&P
|
| "Gary Drescher" wrote in
message
| ...
| | "Jim Macklin"
wrote
| in message
| | news:BQBmg.49424$ZW3.24753@dukeread04...
| | Sorry, I've been attempting to emulate the mental
| processes
| | of a Democrat.
| |
| | Putting aside the vacuous gibe, does that mean you now
| agree that your
| | account of stalls was incorrect? I'm genuinely
concerned
| for the sake of
| | your students. If they were to believe you that an
| ordinary stall involves
| | stalling the tail, then they'd have reason to think
that a
| tail stall isn't
| | a big deal. That would lead them to be less frightened
| than they should be
| | of circumstances that really can cause a tail stall
(such
| as tail icing or a
| | too-forward CG).
| |
| | --Gary
| |
| |
|
|
|
|