180 cowl flaps disappearing at an alarming rate!

[bob turner]

The latest disappeared last week. The hinge is still there, the wire that goes through the hinge is still there, and the part of the actuator that holds the fork is missing. What are we doing wrong?

If the actuator breaks, does that set up enough flutter to destroy half of that hinge? It seems unlikely that the hinge broke first.

New cowl flaps are over a grand each. We haven't priced the actuator lines yet, but I suspect they ought to be new parts.

If our cowl flap beaned any of you, we have a new unlisted number you can call.

 

[StewartB]

Non scientific, but if I disconnected the control end from my 180's cowl flaps and went flying I think they'd survive just fine. Based upon the control effort to open them versus close them when in cruise? My guess is they'd stay mostly closed during flight if allowed to flop free of the control cable.

Stewart

 

[Dave Calkins]

Bob, what year is the 180?

What style piano hinge was used? extruded or folded-over? What fasteners were used to attach the piano hinge to the cowl flap? Those things will get loose, guys will cherry max or olympic rivet them back onto oversize holes and they get loose again. 180's can haul some A, so a loose cowl flap will say b-bye!

If the cowl flap cable is missing the threaded portion that the clevis or rod-end threads onto, the cable itself obviously failed inside the sheath. What vintage is the cable?

You make it sound like you have lost more than one cowl flap, is this true?

Pictures?? DAVE

 

[bob turner]

Yes, two now. The first right after an FAA repair station rebuilt the hinges on both, the second two years later. "J" model, don't know how the hinge was attached or whether it was folded or not. The darn airplane is bulletproof, so these things disappearing is not characteristic of the rest of the airplane.

By the by, same repair station forgot to hook up those rubber dealies on the intake manifold. Had a pretty scary start, but only damaged a piece of scat tube. Talk about getting off easy!

 

[mike mcs repair]

seen many attempts at stopping the wear, siliconeing over the hinges, best idea I've seen was 2 springs on each about 4" long running front to back over hinge in order to always keep tension on hinge pins.....

we lost at least one many years ago... get a little play in hinges and they just set up the right vibration "and poof they were gone....." just like he-haw and usually take part of cable with them (hinge wears through or rips off)

http://www.youtube.com/watch?v=Iqnm3A10m8I :roll:

 

[pzinck]

A good friend lost one of his on a 182 a few months back.

 

[TrentF]

I used to work for an air taxi outfit. During the summer we had to run them wide open most of the time . I'm sure that the prop wash is what destroyed the hinges. and the quickest easiest is like Mike said, silicone over the hinges. (Just be sure to degerease them really well) Make sure you do a good preflight and grab the cowl flaps to make sure they are not getting loose.