On Sat, 06 Mar 2010 19:12:52 -0800, Bret wrote:

Hi, do any gliders have full-span flaperons that also act as airbrakes
(say at 70-90 degree), or do you lose all aileron authority when the
flaperons are that deflected?

Yes. Of course - there's total flow separation on the back of flaps in
landing position, so ailerons would have very little effect if they
matched the flap position.

Take a look at an ASW-20. During normal flight (flaps between -9 and +8
degrees) the flaps and ailerons neutral points move together (in roll
flaps move half the deflection of the ailerons). In landing flap (around
+40 degrees) the ailerons move to -8 degrees to maintain good roll
authority. This is known in RC circles as Crow Mode and the aerodynamic
wing twist induces is a very effective drag generator.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |