Newbie Qs on stalls and spins

"Bill Denton" wrote
You take an airplane to 1,000 ft AGL, and trim it so it is flying
perfectly straight and level. You then close the throttle slightly,
resulting in a slight descent. Even thought you are still flying
straight and level, eventually you will impact the earth, even though
the airplane as a whole (and probably all of it's component parts) are
still "flying".

No Bill..."straight and level" means maintaining heading and altitude

You then take an airplane to 1,000 ft AGL, and trim it so it is flying
perfectly straight and level, but this time you completely close the
throttle. In a short time, the wings will stop producing enough lift
to keep the airplane in flight, it will pitch down and impact the
earth, even though some of the airplane's component parts may still be
flying.

No Bill...in this case, the aircraft will pitch down to maintain the
trimmed airspeed and the airplane WILL NOT stall. Yes, it will descend
until it impacts the ground, but at no time will the aircraft stall.

It is this second condition that most people consider to be a stall.

No Bill...it is called a glide

But since my terminology may not be correct,

Boy...you hit that nail on the head

it is obvious that I am neither an aeronautical engineer, a physisist,
or as yet a pilot

Yes Bill...that is absolutely obvious

I think it is also evident that I do understand at least the basic
principles involved in the discussion.

No Bill... you do not.

Bob Moore
ATP B-707 B-727 L-188
Flight Instructor Airplanes and Instruments (since 1970)
Naval Aviator S-2F P-2V P-3B !958-1967
PanAm (retired)

Let's assume that I am completely wrong. Wouldn't we all have been better
served had you provided correct information as opposed to simply pointing
out my error. I can't learn anything from that.

Given your credentials, could you not have provided me, and many others,
some useful information?


"Bob Moore" wrote in message
. 121...
"Bill Denton" wrote
You take an airplane to 1,000 ft AGL, and trim it so it is flying
perfectly straight and level. You then close the throttle slightly,
resulting in a slight descent. Even thought you are still flying
straight and level, eventually you will impact the earth, even though
the airplane as a whole (and probably all of it's component parts) are
still "flying".

No Bill..."straight and level" means maintaining heading and altitude

You then take an airplane to 1,000 ft AGL, and trim it so it is flying
perfectly straight and level, but this time you completely close the
throttle. In a short time, the wings will stop producing enough lift
to keep the airplane in flight, it will pitch down and impact the
earth, even though some of the airplane's component parts may still be
flying.

No Bill...in this case, the aircraft will pitch down to maintain the
trimmed airspeed and the airplane WILL NOT stall. Yes, it will descend
until it impacts the ground, but at no time will the aircraft stall.

It is this second condition that most people consider to be a stall.

No Bill...it is called a glide

But since my terminology may not be correct,

Boy...you hit that nail on the head

it is obvious that I am neither an aeronautical engineer, a physisist,
or as yet a pilot

Yes Bill...that is absolutely obvious

I think it is also evident that I do understand at least the basic
principles involved in the discussion.

No Bill... you do not.

Bob Moore
ATP B-707 B-727 L-188
Flight Instructor Airplanes and Instruments (since 1970)
Naval Aviator S-2F P-2V P-3B !958-1967
PanAm (retired)

Follow on...

My examples failed because I didn't properly think them through, and
consequently did not account for pitch. Here is what I should have written,
with my corrections in all caps...

You take an airplane to 1,000 ft AGL, and trim it so it is flying perfectly
straight and level. You then close the throttle slightly, resulting in a
slight descent. IF PITCH TRIM IS NOT CHANGED, eventually you will impact the
earth, even though the airplane as a whole (and probably all of it's
component parts) are still "flying".

You then take an airplane to 1,000 ft AGL, and trim it so it is flying
perfectly straight and level, but this time you completely close the
throttle WHILE ATTEMPTING TO MAINTAIN THE ORIGINAL PITCH. In a short time,
the wings will stop producing enough lift to keep the airplane in flight, it
will pitch down and impact the earth, even though some of the airplane's
component parts may still be flying.

I believe these scenarios are correct, and I promise to do better next time!
g

Bill Denton wrote:

You then take an airplane to 1,000 ft AGL, and trim it so it is flying
perfectly straight and level, but this time you completely close the
throttle WHILE ATTEMPTING TO MAINTAIN THE ORIGINAL PITCH. In a short time,
the wings will stop producing enough lift to keep the airplane in flight, it
will pitch down and impact the earth, even though some of the airplane's
component parts may still be flying.

Well, perhaps some might. If you maintain a level pitch attitude in my aircraft
with the throttle closed, the plane will simply descend. The airspeed will be
between 60 to 70 mph with 0 degrees of flaps (stall is about 55 in that
configuration). If you want mine to stall, you'll have to get the nose pretty
high.

Now, if I were to close the throttle and attempt to maintain *altitude* by
raising the nose, she'd stall. When that happens, the nose repeatedly drops a
bit and then goes back up, and the plane descends at a moderate rate of speed in
a nose high attitude.

George Patterson
If a man gets into a fight 3,000 miles away from home, he *had* to have
been looking for it.