Manual flaps saved the day.

gasman · #1 08-11-2012, 02:37 PM

I had my flaps at full extension and was showing a friend something in the panel. He was on the passenger side leaning over and looking in.

Later in the day, I reached in to retract the flaps (manual) and found resistance as I tried to push the handle down. I walked around to the passenger side and found the flap had been pushed past the edge of the wing skin.

If I had electric flaps, I would not have had the feedback needed to realize that something was wrong...... and I would have bent my wing skin.

If you have electric flaps, push on them in the full down position and make sure that they will not allow the wing skin to go beyond the leading edge of the flaps.............. 9, 10, 12 and 14 not an issue.

Sam Buchanan · #2 08-11-2012, 03:08 PM

Quote:

Originally Posted by gasman

I had my flaps at full extension and was showing a friend something in the panel. He was on the passenger side leaning over and looking in.

Later in the day, I reached in to retract the flaps (manual) and found resistance as I tried to push the handle down. I walked around to the passenger side and found the flap had been pushed past the edge of the wing skin.

If I had electric flaps, I would not have had the feedback needed to realize that something was wrong...... and I would have bent my wing skin.

If you have electric flaps, push on them in the full down position and make sure that they will not allow the wing skin to go beyond the leading edge of the flaps.............. 9, 10, 12 and 14 not an issue.

This is an issue that has been discussed several times over the years. There are several variations on this theme. One is as described above, another is not having the anti-scuff tape on the flap positioned correctly to prevent jamming, and the other is having the flap catch the wing walk doubler.

I had the anti-scuff tape catch the wing walk doubler and the flap motor stalled and prevented flap damage. I removed both flaps and trimmed the trailing edge of the doubler back even with the spar so this wouldn't happen again.

Snowflake · #3 08-11-2012, 11:12 PM

And anyone who has a habit of leaving flaps down when parked, try to get into the habit of coming up a notch from the fully extended position before shutting down... 30 degrees instead of 40 degrees, for example. You'll still get adequate clearance to stand beside the plane and reach in, and good visual reminder not to stand on the flap, but you'll protect the flap from getting over-extended because it's partly retracted.

WingsOnWheels · #4 09-05-2012, 10:10 AM

Any thoughts on having separate Up and Down breakers for the flap motor. The breakers could easily be wired in at the switch in series with the switch cross-feed jumper. You could have the standard 7.5amp (not sure if that is correct) on the down feed and a smaller breaker on the up feed. That way if the flap caught the skin the up breaker would trip, hopefully before the skin is damaged. It would take some ground and flight testing to find the right breaker value.

Wayne Gillispie · #5 09-05-2012, 10:43 AM

The flap mechanism slips if overloaded, so I don't think that would work.

longranger · #6 09-05-2012, 01:19 PM

General practice is to size the breaker to protect the wiring, not the end component.

WingsOnWheels · #7 09-12-2012, 09:54 AM

Quote:

Originally Posted by longranger

General practice is to size the breaker to protect the wiring, not the end component.

Very true, but that doesn't mean you can't use a smaller breaker. In this case, you wouldn't be trying to protect the flap motor electrically but rather use the breaker as current limiter. Since the flaps are intermittent use and the load on retract is low, I don't see why it wouldn't work.

JonJay · #8 09-12-2012, 10:42 AM

I still don't understand why this issue is on some wings and not others. My flaps at full (a touch more than 40 deg.) still have at least an inch or more of overlap with the trailing edge of the wing skin. There is no way they can get even close to popping out or catching on the wing skin.
Do some trim the trailing edge of the wing too much? The plans are pretty specific on what it should be. The flaps have the factory bent edge so they have to be the same length. The flap hinge position should be the same.
What gives?