Notchy flap movement

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Joined:17 Mar 2015 11:44
Notchy flap movement

Post by G-ATXZ » 10 Aug 2015 22:22

good evening forum

Has anybody experienced slightly notchy flap movement on their aircraft?

Any advice appreciated



Joined:28 Sep 2015 08:22

Re: Notchy flap movement

Post by D-EEAH » 29 Sep 2015 00:59

Many years ago we had a problem where the flap operated normally on the ground, but in flight would not deploy beyond (IIRC) about 50% travel. I believe the problem was that the mechanise involves a fibre composite cog (possibly a part sourced from a BMW electric window mechanism I was told! - just as the canopy handle is a FIAT 500 door handle and the rubber on the steps are BMW break pedal rubbers!) and this had become worn, so that it worked on the ground but in flight it slipped when pushing against the air loads. A new cog was obtained and the problem went away and 600 hrs later remains OK. Perhaps your cog is worn or damaged. I presume the trackways at the wing root that the lever slides in are clean and lubricated?

Joined:08 Jan 2015 12:08

Re: Notchy flap movement

Post by G-BIJD » 30 Jun 2019 17:19

I am having the same problem, my flaps will deploy fully on the ground but will blow back a few degrees in flight due to air loads.
Does anyone know the part number of the cog ??


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