Flap down limit

I have installed the Van's electric flaps and now they go down what I think is to far. I have read about the leading edge of the flaps hanging up on the wing trailing edge . Would like to avoid any chances of this happening but have not come up with a way to limit my down travel with the electric flaps with out going the limit switch route which I'd like not to have to do. I'm sure there is a simple solution but I'm not seeing it..... Help please.

How far do they go?

How much of the flap "lip" is left still under the wing skin?

I don't remember all the why's and wherefor's, of my 6A's flaps. But as I remember, full down is 40 degrees. You can measure that with one of those revolving protractors that usually have a magnet on the bottom. My flap linkage is set, so that the motor is at it's end of travel when it reaches full down. No additional down limit required.

I did have a case, to where someone possibly stepped on the passenger side flap area. This caused the lip to contact the wing walk stiffener that extends past the rear spar. When the flap was raised, it bent that stiffener. I got under the wing, placed a piece of sheetmetal between the stiffener & wing sheet, and cut off the stiffener with a small cut-off wheel on a dremel tool.

L.Adamson --- RV6A

RV-6 Flap travel

On the ground my flaps will go down 45 degrees as measured with a electronic level. In the air, the force of the air against the flap limit travel to 40 degrees (I have it marked). At these angles of extension the flap top skin will not pop out from under the top wing skin. That said, if you leave the flaps down all the way and lean on with a leg as you reach into the cockpit you can cause it to pop out. I found out the hard way. The simple solution is that after landing with full flaps I always retract them 5 to 10 degrees.

I never thought about the air load on the flaps. I too get 45 to 47 degrees just running the flaps down till they stop. That far down there really is not much of an over lap between the leading edge of the flaps and the trailing edge of the wing. I do have the degrees marked on the pilots side and had decided just to use 30ish degrees when needed instead of 40 degrees. I was just looking for an easy way to limit my down travel so I would not go to far some day when my mind was else where. Looking at the marks on the flaps is the best solution....
Thanks,

1Oldguy said:

I never thought about the air load on the flaps. I too get 45 to 47 degrees just running the flaps down till they stop. That far down there really is not much of an over lap between the leading edge of the flaps and the trailing edge of the wing. I do have the degrees marked on the pilots side and had decided just to use 30ish degrees when needed instead of 40 degrees. I was just looking for an easy way to limit my down travel so I would not go to far some day when my mind was else where. Looking at the marks on the flaps is the best solution....
Thanks,

Click to expand...

I'll check tomorrow, to see what my flaps run down to. It's never been a case, of where they can run too far. Much of the time, I only use 1/2 flaps in the 6A.

edit: 1/2 flaps because I have a C/S prop, and it comes down fast enough as it is.

L.Adamson --- RV6A

L.Adamson said:

My flap linkage is set, so that the motor is at it's end of travel when it reaches full down. No additional down limit required....

Click to expand...

Gee Larry, in this case we actually share the same experience. At full 40° of flap travel, if I continue to depress the flap toggle located atop the joystick grip, the slip clutch on the flap motor just goes into action. The flap linkage itself will not physically allow the flap to travel past 40° of deployment. Because of that limitation, there remains ample flap material tucked under the wing skin. Besides, my 2000 kit includes a small factory notch cut into the upper leading edge of the flap skin. Similar in general principal to the "suicide hole" drilled through the threads on a Heims bearing, as long as that factory cut notch is not exposed during full flap deployment, there seems to me very little risk the flap skin can pop out. I have to openly wonder if many reported problems with the flap skin popping out can really be traced to an improperly rigged flap linkage.

Flap limit setup

Flap limit setup found here if interested...

http://www.vansairforce.com/community/showthread.php?t=61970&page=2

There are photos of installs and info for switches available, just PM me.

thx...