>I'm wondering - maybe I should turn all these gyro realism off,
>as it is rather not important during FS training, not quite
>realistically simulated, and not very difficult, I suppose,
>to take care of in a real Cessna

Umm. IRL, your instructor will train you to check the directional gyro
with the magnetic compass every 10 minutes or so. In a lot of older
training aircraft, the drift can put you off course pretty quickly.
Also, on the flight test, the examiner will be watching to make sure
you cross check as well. So it's not a bad habit to get into.

As for yaw, yes you'll definitely need to use pedals to adjust for that
especially when taking off with the usual full power. Pulling power
can also cause a yaw in the opposite direction! Airplanes with a
propeller rotating the other way than we're used to in the US (for
example, I believe, some WWII British fighters) will have takeoff yaw
to the right, btw.

Cheers, Kev

> wrote in message
oups.com...
> [...] Pulling power can also cause a yaw in the opposite direction!

No, it won't.

Latet, for what it's worth, I'll suggest that a simulators newsgroup isn't a
very good place to get actual airplane *facts*. :)

Peter Duniho wrote:
>
> Very few light general aviation airplanes have "self-correcting"
gyros
> (known as "slaved" gyros, because they are slaved to some sort of
actual
> magnetic compass, usually solid state), but it's true that they
exist.
>
> Actual drift in an actual airplane varies wildly. A brand-new gyro
with
>
> Pete

Regarding solid-state:

I thought this too until a RAS'er (the other one: rec.aviation.student)
set me straight; and I have one :-)

The King KCS 55a, in a typical installation uses the KMT 112 remote
Flux Valve (a liquid filled magnetic compass) - Not solid state.

http://www.seaerospace.com/king/kcs55a.htm

a.

>> [...] Pulling power can also cause a yaw in the opposite direction!
>
> No, it won't.

I said "can cause". Yes, it can, and does... but I should've been
clearer.

First, in many trainers the major left-turning tendency is from the
corksrewing propeller slipstream... about twenty times the precession
force, ten times the P-factor, and three times the torque force (which
is a banking force really). So, as you alluded to, planes are designed
to compensate at cruise for this by slightly canting the engine to the
right, and the vertical stabilizer to the left.

In a high-power, low-speed situation like the takeoff roll, the
slipstream wind hits the tailfin from its left, thus increasing the
angle of attack and causing the tailfin to move right (left yaw).

Conversely, in a low-power, high-speed situation like a descent, the
slipstream force is much less than the oncoming air, and the slight
left cant of the vertical stablizer causes a slight _right_ yaw, which
often has to be compensated for with a little _left_ rudder. This is
what I was thinking of when I said "pulling power".

>Latet, for what it's worth, I'll suggest that a simulators newsgroup
isn't
>a very good place to get actual airplane *facts*. :)

I'd agree that most replies on the net are by necessity in some way
incomplete. For example <grin>, when you mentioned friction and
precession as causes of gyro drift, you left out the fact that gyros
operate in what's known as "inertial space". The motion of the earth
itself through the universe will always mean that gyros cannot forever
stay correct from an earthling's point of view. This is most visible
at the higher latitudes (above and beyond the variation differences you
pointed out).

For a neat example: consider that you're parked at the North pole, and
you set your DG to "N". It's pointing towards a certain direction in
space. But wait twelve hours and the DF will read "S", because the
earth rotated the entire plane halfway around. However, this is just
nit-picking and all in fun :)

Cheers,
Kevin

> wrote in message
oups.com...
> [...] This is what I was thinking of when I said "pulling power".

I would describe that as "a reduced power setting". To me, "pulling power"
is an action, not a state of being.

> I'd agree that most replies on the net are by necessity in some way
> incomplete.

I don't mind incomplete. No one's looking for a graduate level course here.
I'd be satisfied with leaving out all the incorrect statements.

Pete