Coordinated turns without rudder, and autopilots

On May 27, 7:44 pm, Mxsmanic wrote:
How do autopilots make coordinated turns even when they cannot control the
rudder?

As others have posted, most lightplane autopilots don't adjust the
rudder for adverse yaw when turning, so you do get a few seconds of
slightly uncoordinated flight. However at normal cruise speeds this
creates no hazard or discomfort.

If flying close to stall, the autopilot should be turned off even for
straight and level flight. If the airplane is on the verge of
stalling and starts to turn because of engine p-factor or any other
reason, the autopilot will attempt to correct with aileron. This may
actually induce stall on one wing, producing sudden wing drop and a
potential spin.

Paul kgyy writes:

As others have posted, most lightplane autopilots don't adjust the
rudder for adverse yaw when turning, so you do get a few seconds of
slightly uncoordinated flight. However at normal cruise speeds this
creates no hazard or discomfort.

So in theory I should be able to turn myself with ailerons only in the same
way, without the need to use the rudder to stay coordinated. What's the
secret? Each time I try to turn at the same rate that the AP manages, I have
to use the rudder to stay coordinated.

If flying close to stall, the autopilot should be turned off even for
straight and level flight. If the airplane is on the verge of
stalling and starts to turn because of engine p-factor or any other
reason, the autopilot will attempt to correct with aileron. This may
actually induce stall on one wing, producing sudden wing drop and a
potential spin.

I have an aversion to stalls and I usually stay well away from them. The AP
will put the aircraft into a stall if airspeed is too low to maintain altitude
easily (I don't know if this is an artifact of simulation or just like the
real thing--I know my simulated autopilot doesn't have all the modes of the
real one).

"Mxsmanic" wrote in message
...
Paul kgyy writes:

As others have posted, most lightplane autopilots don't adjust the
rudder for adverse yaw when turning, so you do get a few seconds of
slightly uncoordinated flight. However at normal cruise speeds this
creates no hazard or discomfort.

So in theory I should be able to turn myself with ailerons only in the
same
way, without the need to use the rudder to stay coordinated. What's the
secret? Each time I try to turn at the same rate that the AP manages, I
have
to use the rudder to stay coordinated.

If flying close to stall, the autopilot should be turned off even for
straight and level flight. If the airplane is on the verge of
stalling and starts to turn because of engine p-factor or any other
reason, the autopilot will attempt to correct with aileron. This may
actually induce stall on one wing, producing sudden wing drop and a
potential spin.

I have an aversion to stalls and I usually stay well away from them. The
AP
will put the aircraft into a stall if airspeed is too low to maintain
altitude
easily (I don't know if this is an artifact of simulation or just like the
real thing--I know my simulated autopilot doesn't have all the modes of
the
real one).

It's honestly just one of those things that do not hold true to form on PC
simulators. But turns do not always have to be perfectly coordinated.
Especially shallow ones initiated by wing levelers or low end autopilots.

Maxwell writes:

It's honestly just one of those things that do not hold true to form on PC
simulators.

Real autopilots on real aircraft do not necessarily have control over the real
rudders, and yet they execute real coordinated turns without those rudders.
How do they do it?

But turns do not always have to be perfectly coordinated.

Why are they more coordinated when performed by the autopilot than when
performed by the pilot (without rudder)?

Especially shallow ones initiated by wing levelers or low end autopilots.

Autopilots often put the aircraft into a standard-rate turn, which isn't
exactly shallow, even if it isn't terribly steep.

Mxsmanic wrote in
:

Maxwell writes:

It's honestly just one of those things that do not hold true to form
on PC simulators.

Real autopilots on real aircraft do not necessarily have control over
the real rudders, and yet they execute real coordinated turns without
those rudders. How do they do it?


They don't fjukkwit.


Bertie

"Mxsmanic" wrote in message
...
Maxwell writes:

It's honestly just one of those things that do not hold true to form on
PC
simulators.

Real autopilots on real aircraft do not necessarily have control over the
real
rudders, and yet they execute real coordinated turns without those
rudders.
How do they do it?

They don't.


But turns do not always have to be perfectly coordinated.

Why are they more coordinated when performed by the autopilot than when
performed by the pilot (without rudder)?

They are not.


Especially shallow ones initiated by wing levelers or low end autopilots.

Autopilots often put the aircraft into a standard-rate turn, which isn't
exactly shallow, even if it isn't terribly steep.

No, it's not.

On May 29, 1:37 pm, Mxsmanic wrote:


Why are they more coordinated when performed by the autopilot than when
performed by the pilot (without rudder)?

Especially shallow ones initiated by wing levelers or low end autopilots.

Autopilots often put the aircraft into a standard-rate turn, which isn't
exactly shallow, even if it isn't terribly steep.

They also start the turn rather gradually, which minimizes the adverse
yaw.

If I hand-fly a standard rate turn, the rudder application only lasts
for maybe 3 seconds at the beginning and end of the turn.

So in theory I should be able to turn myself with ailerons only in the same
way, without the need to use the rudder to stay coordinated. What's the
secret? Each time I try to turn at the same rate that the AP manages, I have
to use the rudder to stay coordinated.


As Maxwell observes, this may just be a simulator limitation. In
actuality, a small amount of rudder should be applied when initiating
and recovering from a turn, but once in a constant bank turn, the
aircraft will normally be in coordinated flight without rudder
application.

Paul kgyy writes:

As Maxwell observes, this may just be a simulator limitation. In
actuality, a small amount of rudder should be applied when initiating
and recovering from a turn, but once in a constant bank turn, the
aircraft will normally be in coordinated flight without rudder
application.

But the autopilot has no control over the rudder, and yet the turn is
coordinated. What is it doing to make this possible?

Mxsmanic wrote in
:

Paul kgyy writes:

As Maxwell observes, this may just be a simulator limitation. In
actuality, a small amount of rudder should be applied when initiating
and recovering from a turn, but once in a constant bank turn, the
aircraft will normally be in coordinated flight without rudder
application.

But the autopilot has no control over the rudder, and yet the turn is
coordinated. What is it doing to make this possible?


Your mental condition, apparently.


Bertie