A very basic question

"Mike Rhodes" wrote in message
...
[...signed...]
(I think this is ~correct. Pretty sure.)


You ought to *know* before you post, I guess.

With respect to your specific comments:

The simple answer is that, theoretically, the ailerons act exactly as you
would think. That is, a turn is not caused by a change in bank.

In level flight, the wings are generating 1g of lift, equivalent to
the weight of the aircraft and all occupants inside. If this lift
vector is rotated by the ailerons then it will point in the direction
of the rotation, and therefore force the aircraft to change its
direction of flight, and therefore to turn.

Wrong. In the theoretical case I describe (which isn't the reality case
anyway), banking would simply cause the airplane to sideslip sideways,
without any turn occurring.

The "1g of lift" stuff is irrelevant, except inasmuch as there IS lift (a
force) that is redirected sideways.

A more complicated answer is that since the "center of lift" is ahead of
the "center of gravity", having the lift vector tilted to one side or
the other
by bank does pull the nose of the airplane around a bit, inducing a turn.

If the center of lift actually was ahead of the center of gravity then
the aircraft would loop nose-up, so it isn't. They are aligned.

Wrong, again. The center of lift is actually behind the center of gravity
(I screwed up in my original post). The horizontal stabilizer balances out
the difference in force to prevent the nose from dropping as a result of the
difference.

To revist my original post, the correct statement would have been "since the
'center of lift' is behind the 'center of gravity', having the lift vector
tilted to one side or the other by bank does pull the nose of the airplane
around a bit, inducing a turn *opposite to that intended*."

I apologize for resulting confusion, but the fact remains that your
statement is entirely incorrect.

[...]
An even more complicated answer points out that the ailerons themselves
create increased drag on the raised wing and reduced drag on the lowered
wing, which creates a yaw opposite in direction to the intended turn.

More or less. A lowered aileron has the increased drag, while a
raised aileron has less drag. This will pull the nose around opposite
from the direction of expected bank.

Heh...one of the few things you get right, and it's exactly what I wrote.

Adverse yaw is the ailerons acting in place of the rudder, and it
prevents the aircraft from lining perfectly into the wind.

"In place of"? Uh, okay...I guess you could say it that way.

But once the aircraft is banked then the aircraft will turn. The
aircraft turns because it is banked.

No, it does not. Any turn as a result of bank is actually due to other
design features of the airplane, such as dihedral and a vertical stabilizer.

Pete