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Sig Banshee flap/elevator travel questions.

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Electric George:
Hi All,

I am using a carbon rod for the pushrod between the elevator and flap. As I have moved the wing forward I had to use something other than the kit supplied wire anyway.

The plan shows the pushrod in the lowest horn position to the surface but this means the flap hits the pushrod when it moves up.

Looking at pictures of the Banshee I see the pushrod bent in an arc to avoid the flap (no good with carbon tube) or moved to the top hole on the horn.
I can move the pushrod to the highest horn position which gives much more movement.
How much  surface throw should I be aiming for? Should it be the same throw for both flaps and elevators on the Banshee?
I have read that Jack Sheeks suggests cutting the flap with the horn. Is that simply cutting a notch out of the flap to create more clearance?

Thanks

Dennis Toth:
30 - 35 deg deflection is all you need. You need to position the rods in the holes that give equal deflection of flap and elevator. You must avoid having more flap deflection then elevator. With the CF rod just cut a notch in the flap to clear. Make sure the CG is correct and the leadouts swept 3/8" behind the CG (center of leadouts).

Best,    DennisT

Motorman:
You need the push rod from the bellcrank to go to the top hole on the flap horn. As others have said just cut a notch in the flap for clearance.

Ken Culbertson:
Motorman chimed in as I was writing this, and he is correct.  BC to Outer Hole on flap horn.  The Banshee was designed for a 3" bellcrank.  Is yours 3 or 4"   Also, are you using nylon horns vs a one-piece metal? Both are going to require a cutout but with the 1-piece metal you can make a wide TE Faring/Fillet on each side and position the horn so that the controls are over it.  This keeps the flaps without a cutout, you maintain your original size ratio and cut down tail wiggle just a bit.  Ratio of 1:1 is good but 2:3 might be better (30 Flap, 45 Elevator) depending on how you fly corners.   It is 100% personal preference, but I don't like only having as much control as you need for normal circumstances. Dennis is also right, 30 - 35 degrees on the elevator is probably about 5 degrees more than you will use but it is also all you will have if you really need more.

Ken

Electric George:
Hi all,
Thanks for the replies; I do love this forum!

Dennis - great info, I will check all of that.
Motorman - Great tip regarding moving belcrank rod to outer hole.
Ken - I am using the kit supplied 3" belcrank and the kit supplied nylon horns. Very interesting thoughts and ways to set up the flap/elevator. No flying of corners for me yet! I am using an elevator only model to learn the basic stunts but will hopefully fly the Banshee soon (even if I then put it aside until next year).

Thanks again, that knowledge gives me something to aim for now.   

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