..A major cause of the appalling carnage is the "tip stall"
.
.It generally occurs on the first turn after takeoff, or the turn to downwind,
or the turn to base,.. not so frequently on the turn to final.. the planes which are
going to tip stall are usually piles of sticks by this time..
The solution rests on the cause. A down-going aileron increases the angle of attack
of the wing on that side. As the planes are generally close to the stall alpha, this
stalls that side of the wing. The unstalled wing then rotates the plane to the stalled side.
One cure is to have small ailerons, inset some distance from the tip, so most of the
outer wing can remain unstalled. However this doesn't always work.
I've tested another method which appears quite promising.. Aileron differential is programmed
into the transmitter.
The ailerons move UP only! When one side goes up, the other side stays
aligned with the wing. It doesn't go down, so that side won't stall.
Manuverability is not a prime requirement for this event in any case, so nothing is lost control-wise.
The planes I've tested this one fly the required manuvers quite well.
Coupling the rudder to the aileron (1->4 mix) is usually a good thing also.
..Ist page, 2002....
.Previous Society of Automotive Engineers Aero Design competitions.
Link to S.A.E.
Aerodesign West information:
E-mail to: Paul J. Burke
SAE2002p4.htm...04-04-2004
