When do controls return to neutral?

EridanMan writes:

That is, lets say I trim for 110 knots at 4000 feet,
75% power, and fly hands off for a bit. now - if I pull back on the
yoke, i'll trade some of my airspeed for climb ("zoom climb")... the
further I get off my "target" speed, the greater the yoke is going to
push against my hands... now - the "weird" thing (not really when you
think about the physics, but certainly not intuitive to sim-drivers) is
that if I then decide to release the yoke, the aircraft will
_completely automatically_ return to its trimmed airspeed, and pretty
close to its original altitude.

The sim behaves the same way, but without any control forces as
feedback. However, it is indeed counter-intuitive at first. It
dawned on me quickly enough why this is so, but initially one tends to
think that an aircraft will go straight into the ground once it is
pointed down, or infinitely high once it is pointed up. (Thinking a
bit about the laws of physics rapidly shows that this cannot be the
case, but the influence of popular notions is strong.)

That is why
flying with the trim is generally a bad idea - fly with the yoke, trim
off the preassure = flying precisely.

It's the latter part that's hard to simulate.

What I sometimes do is set the autopilot for my altitude, let it set
the trim (which it does with much greater precision than I have
available to me), and then shut it back off, with the aircraft trimmed
for my current altitude. If I'm on A/P for a long time and I wish to
fly with it off, I adjust power until the A/P has trim set to zero,
then I shut off the autopilot. This gives me a stable aircraft with
neutral trim, which insures that I have full control authority in both
directions. (If I were to shut off the A/P while it has heavy trim in
place, I might not have the authority I need later, unless I carefully
retrim myself, which is awkward for reasons I have already stated.)

There is a "takeoff point" for the trim system, generally set to
provide good yoke feel for Vy climbout.

I see that on several aircraft in the sim. I don't use take-off trim
because I don't want to be misled into thinking that I have more climb
ability than I actually have. By leaving trim neutral I can tell how
much I have to persuade the aircraft to climb, and so I have less
chance of an unpleasant surprise if I need more elevator authority.

Once you are airborne, simply use the yoke to SET the
aircraft off of its currently trimmed configuration, and then use the
trim controls to adjust the trim configuration to the current
configuration- that is really most of flying.

I try to do this. It's awkward with no feedback, but it's still
possible from watching the instruments. And the better I know a given
aircraft, the better I can estimate how much to change things to get
it trimmed quickly.

Still, I don't think I trim nearly as much as many real-world pilots.
Unless I plan to be in the same attitude for quite some time, I leave
the trim alone. I especially worry about it being a distraction
during critical phases of flight--spinning the trim wheel while I
should be looking at instruments or talking to ATC seems risky. And
from what I understand, the only advantage of trim is that it
eliminates excess control pressures ... but I can tolerate those for
the brief period of take-off and landing.

There was some discussion on A.net about this - Boeing goes to great
lengths in their FBW systems to keep the 'feel' of traditional
hydrolics, trim and everything. Airbus, on the other hand, just has
the aircraft automatically and always trim for 1-G flight.

Another reason to prefer Boeing. Boeing designs for pilots; Airbus
designs for computer gamers.

I.E, the airbus actually flies more like your flight simulator than my
Piper

See above (I wrote the above before reading this).

I haven't read that either way - but I think you over-estimate the
necessity of knowing where your control's "really" are.

Maybe. I guess it's from association with other types of vehicles.
One doesn't set a car to veer consistently to the right, for example,
but cars don't move in three dimensions.

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