[RCSE] Spoileron/aileron reaction

[Tord <tord@xxxxxxxxxxxxxxx>]

It is not that easy to predict how a model
behaves when spoilerons are activated, just as
flaps and dive brakes can create various reactions.

Spoilerons (which in essence are ailerons, or flaps,
just moving upward, instead of both upward and downward).

Many aircraft, model and full-size, pitch up with the
developement of flaps (or flaperons), like the DAW S1-26 HLG,
as the flow over the wing hits the stabilisator at a 
different angle than before - and the nose down momentum of
the flap is more than amply compensated by the stabilisator.

A T-tail is probably less affected by the the downwash behind
the flaps - and a few aircraft run out of elevator power when
full flaps are deployed, unless a lot of extra incidence is
cranked in - my friend's B-17 acts just like that at low speed,
due to the great shift of CG as the gear goes down and forward 
to lock down, plus the flaps momentum adds up to more than
normal elevator power.

Most spoilers and spoileron, and crowed ailerons, result in
a nose up momentum, but there might be exceptions :-)?

Tord,
Sweden

-- 
If reply difficulties - use tord@xxxxxxxxxxxx

Tord S. Eriksson, Ovralidsg.25:5, S-422 47 Hisings Backa, Sweden

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