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Re: REFLECTOR: elevator cuffs

Jack and friends,

Elevator cuffs limit elevator authority at low speeds to prevent deep stall in small
winged Velocities.  Relative to the main wing the STD V has a bigger canard than the
LW and XL  V.

The large wing Velocities are safer without cuffs because this gets the take-off and
landing speeds down.  These planes have a lot of safety margin at aft CG were they
fly best and cannot be PIO forced to main wing stall (deep stall).  If a larger
canard or engine is added to the LW(173) model then the elevator cuffs should be
added plus then you are a test pilot.

On the smaller winged Velocities if the whole cuff has to be removed to get
sufficient rotation or flare then the canard didn't have enough camber or incidence
to begin with.
Again, you have become a test pilot.  **The difference in the canard and main wing
incidence/area/camber is what loads the canard up first preventing main wing
stall.**    The trueness of the wings, L.E. radius, AC weight/balance and pilot
weight are also factors.

A lot of elevator/canard authority can add utility and safety to your Velocity but
if yours has gone so far that it can be made to buck violently then don't push that
end of the envelope.  Violent bucking precipitates roll and yaw oscillations as
well.   No fun.
When it first starts to buck it is telling you...... push the nose over a little.

Alan Shaw