Flaps won't extend beyond 2/3
 

They work fine up/down in the 1/3 and 2/3 position, but when the selector is placed in the full position, flaps stay at 2/3 position.

Ideas?:confused:

A word of caution is that a flap setting beyond 2/3 MAY be dangerous.

There have been instances of a flap cable breaking on one wing and the aircraft rolling uncontrollably because of insufficient authority of opposite aileron when in full flaps. The problem may even occur at 2/3 flaps. Depending on altitude and how quickly you a) apply opposite aileron and b) raise the extended flap on one side, accidents have occurred and I believe there have been fatalities.

As a result, I adhere to several precautions. At annual inspections I give special attention to the flap-cable inspections. In flight I use more than 1/3 flaps only when absolutely necessary and I lower flaps at a higher altitude as a test, with my hand next to the flap lever to instantly raise the flaps if a cable breaks. So virtually all my landings are at 1/3 flap, where a quick calculation based on aileron and flap surface areas and moment arm indicated that 1/3 flaps on one side can be overcome with full opposite aileron.*

Ernie


_________________
* I'm an aerospace engineer with an MS from Caltech.

I got it figured out. The push-pull cable that attaches to the flap indicator was out of adjustment. The flap indicator interacts with two switches on the flap position selector. They both move, so its a fairly precise little Rube Goldberg mechanism. The push pull wouldnt allow the indicator to go to the full down position, which in turn caused a switch to not be pressed. I took some pics that I will upload later. Files are too big so site wont let me from my phone.

Pics attached. Had to remove the pedestal cover to access the flap selector switch. For pressurized models, you have to remove the dump valve t-handles and securing nuts before you can remove the pedestal cover.

Pursuant to Ernie Martin post, I have read with interest information under technical data at this website’s home screen regarding flap cables and inspection.