Rotation

Jose wrote
This makes no sense to me.

Yes Jose, we do understand that a lot of things make no sense to
you.

If the airplane attitude remains "where desired"
(I presume that is the same as where you put it, using
pressure) when you release the pressure, then the pressure isn't
doing anything. How do you fly such an aircraft?

First.....Put the nose where desired and feel pressure on the yoke.
Second....Start trimming, airliners generally use electric trim.
Third.....Stop trimming....release pressure on yoke
Fourth....Check nose position, if it stays where you put it, you
did the correct amount of trimming, if not, repeat the
procedure as many times as required.
Fifth.....If all else fails, turn on the autopilot and let it trim.

Actually, on the older Boeings that I flew, the pilot could do a
better job of trimming than the autopilot since the autopilot did
not mind holding a little pressure forever. Only when the elevator
became some number of units out of alignment with the stabilizer did
the autopilot kick in the stabilizer trim system. It was common that
when flying on autopilot,if a pilot observed on the control surface
deflection indicators that the autopilot was actually holding some
'up' elevator, he would use the manual trim wheel to fair the elevator
and stabilizer and reduce the 'trim drag' which could consume a lot of
fuel.

Bob Moore

Third.....Stop trimming....release pressure on yoke

Are you maintaining pressure on the yoke as you trim? IN the spam cans
I fly, I am relaxing pressure and keeping the position of the nose
constant. When I'm out of pressure, I stop trimming. Now I don't fly
jetliners but the physics is the same, no?

Jose
--
There are more ways to skin a cat than there are cats.
for Email, make the obvious change in the address.

Bob Moore wrote:

Actually, on the older Boeings that I flew, the pilot could do a
better job of trimming than the autopilot since the autopilot did
not mind holding a little pressure forever

That is true of the S-Tec 60-2 autopilot in my Bonanza, too. At the top of
climb and upon selecting the ALT hold as the aircraft's speed increases,
the AP will keep the aircraft level all while fighting a slight nose up
trim. Disengage the AP and the aircraft will immediately nose up a few
degrees if the pilot is unprepared (i.e. improper pressure in the yoke).

I have learned to first allow the aircraft's speed to stabilize and then
disengage the AP to manually retrim for level flight before re-engaging the
AP. Having all that tension in the system just doesn't seem right to me.

--
Peter

"Mxsmanic" wrote in message
...
..

Also ... why does a plane like the Baron 58 have a stick pusher? I
presume you can't use it for instruction flights that teach about
stalls, since it refuses to adopt an attitude that will cause a stall.

Where did you read that a Baron 58 has a stick pusher?

Jose wrote
Are you maintaining pressure on the yoke as you trim? IN the spam cans
I fly, I am relaxing pressure and keeping the position of the nose
constant. When I'm out of pressure, I stop trimming. Now I don't fly
jetliners but the physics is the same, no?

Nope! If you are holding say...5 pounds of pressure and you electrically
trim for 10-15 seconds, you will still feel the same pressure.

As I said, teaching a new student to trim an early Boeing was a real chore.

Bob Moore

Now I don't fly
jetliners but the physics is the same, no?
Nope! If you are holding say...5 pounds of pressure and you electrically
trim for 10-15 seconds, you will still feel the same pressure.

Ok, then what happens if you electronically trim for the "right" amount
of time. You still feel some pressure but you are in trim. You release
the pressure and the nose stays in the same position. NOW you apply the
exact same pressure you had before you released. Does the nose go up?
Why? What happened in the interim?

Jose
--
There are more ways to skin a cat than there are cats.
for Email, make the obvious change in the address.

Mxsmanic wrote:

Also ... why does a plane like the Baron 58 have a stick pusher?

It doesn't, unless you are referring to the interface between the yoke and
the seat cusion.

--
Peter

"Jose" wrote in message
.. .
Third.....Stop trimming....release pressure on yoke

Are you maintaining pressure on the yoke as you trim? IN the spam cans I
fly, I am relaxing pressure and keeping the position of the nose constant.
When I'm out of pressure, I stop trimming. Now I don't fly jetliners but
the physics is the same, no?

You are both describing the same action, Bob should have just said "release
the yoke" if the nose stays where you want it you are trimmed. : )

You are both describing the same action, Bob should have just said "release
the yoke" if the nose stays where you want it you are trimmed. : )

Well, that's not the way I read the original post that raised my
question, and prompted Jay Beckman's comment that there is a lot that
makes no sense to me:

[Jay Beckman:] Trimming is a "feel" thing. You trim to relieve control pressures and
you can't see pressure, you can only feel it.

[Bob Moo] Except in an airplane where the trim system moves the horizontal
stabilizer instead of a trim tab. In that case, there is no feel
feedback to the yoke. One must release the pressure and see if the
airplane attitude remains where desired.

From this I gather that there is no difference in pressure on the yoke
when you are trimmed vs untrimmed. "One must release the pressure and
see..." Is the pressure so light that one flies much like a
non-force-feedback simulator? This would be very weird for me. I'm
used to flying real airplanes, not giant tubes with wings on them.

Jose
--
There are more ways to skin a cat than there are cats.
for Email, make the obvious change in the address.

"Peter R." wrote in message
...
Mxsmanic wrote:

Also ... why does a plane like the Baron 58 have a stick pusher?

It doesn't, unless you are referring to the interface between the yoke and
the seat cusion.

--
Peter

Izzat the same device as the "nut holding the yoke?"

g d r

Jay B