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Re: wing / strake incidence



Andrew L. Judge wrote:
> 
> If the wings are critical, what about the strake incidence?  It is really
> emphasized in the plans that the strake incidence be correct with little
> deviation from the measurement.
> 
> Also, how many people have the room to set both wings and build both tanks
> at the same time to insure the main wings are set correctly, then put on
> the canard and set that with both wings on. I was very fortunate to have
> the space to do this, but I know some of you are building in basements and
> garages.   I am really interested in this since my plane is in paint and I
> would hate to jig and paint the canard for a second time.
> I just fired up my engine (Lyc.) last week and will be going to the airport
> soon for first flight.
> 
> Andy Judge
> N55AJ  Std. FGE

Andy,

If I remember right, the wing incidence is 2 degrees and the the canard
incidence is 6 degrees. The wing is measured just outboard of the strake
and inboard of the aleron. The "factory" supplies a guage made for use
with the shaw canard and needs to be modified for the builder built
canard. I sent both of the gauges back for checkout just prior to
setting the canard. Scott sent me a new wing guage (the old one was
warped 1/2 degree), and said my modified canard guage was okay for the
homebuilt canard.

Thus, the the plane has a 2 degree "angle of attack". The whole process
begins when the fuseloge is first set with a "level", and then a "level"
is used to mark a 66" line from the bottom of the main spars to the 
Elite doors. Another line is drawn 2 1/8" above this one just along the 
middle of the door. (These figures are the best ones I can remember for
a standard Elite). Thus, the "level" line has been set to a different
part of the plane, and the "angle of attack" is set when the
inboard leading edge of the lower strakes are permanently attached.  

The wings are then set, and the out board leading edge of the strake is
aligned with inboard leading edit of the wing. The right outboard
leading edge of my strake "drooped 3/8", my left leading one was okay.

In the end, with the wings and the canard on, both guages were
perfectly level with the plane sitting on the floor and a 2 x 4 under
the nose gear. The most important thing is the difference between
the two guages (6 - 2 = 4 degrees). I believe this is how the factory
would check your guages with one of their well flying velocities.

In the future, if you every want to discover the level line of the
airplane, reverse the above 2 1/8" and 66" measurement.

Carl Hoffman

P.S. Are you or Denis going the be at Oshkosh again this year?