Re: Misconceptions: adverse yaw

[John Denker <jsd@MONMOUTH.COM>]

At 11:13 AM 8/14/99 -0500, brian whatcott wrote:
> Currently available light aircraft show little or no adverse yaw
> because it can be largely abolished by the use of differential ailerons.

I've flown quite a few different types of aircraft (from Piper Cubs to
turboprops).  Most of them can be flown "with your feet on the floor" in
typical cruise conditions, but at lower speeds you need to apply some
rudder to maintain nonslipping flight when the ailerons are deflected.

I have flown things with differential aileron deflection, Frise ailerons,
and rudder/aileron interconnections.  As theory would lead you to expect,
these *reduce* the amount of adverse yaw, but they cannot abolish it across
the entire range of airspeeds.

Also note that in turbulence you might want to deflect the ailerons to
*prevent* a roll;  there is no way any mechanical trickery can get the
right answer in such cases.

I've never flown a MU-2.  That has spoilerons instead of ailerons,
resulting in rather unusual handling characteristics.  Similarly, I've
never flown an Airbus or F-18 or anything else with fly-by-wire controls,
but I think such things are outside the scope of this discussion.

> I see that John seems to have missed my mention that control of
> turns in low powered aircraft was dicussed in descriptions of the
> wonderful man-powered aircraft development story.

I saw that you mentioned it.  I was seeking more than a mention.  I was
hoping you could provide some details and/or a reference.