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Author Topic: 560A flap control  (Read 3374 times)

Sparkskeywest

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560A flap control
« on: July 09, 2018, 05:58:07 am »
I recently aquired N4700, previously owned by retired Northwest pilot Ray Fenner. Ray kept the aircraft in his hanger in Jupiter, Fl for the past 30 years, however she has been unattended for 4 years. My A&P / IA is doing an annual now and other than the usual squaks,she is pretty fit.

A couple of questions: The nitrogen accumulator tank. Is there a special valve that fits in the bottom of the tank for filling or is it a schrader, and what components does this back pressure balance.

Flaps cycle, but only full down. The flap handle controls a hydraulic valve so I assume that there are no micro switches. Please explain this system and what we should be looking for as a fix. (Is this associated with the accumulator?)

One of the generators is intermittent. Any ideas on where to find a replacement and other Commander specific parts?

Thanks in advance. David Stiles, Key West, Fl.

ghancock

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Re: 560A flap control
« Reply #1 on: July 09, 2018, 09:58:09 am »
there should be a gauge and schrader valve in left wheel well and it should have markings for filling, usually around 300lbs or so.  Pretty simple to do and usually har d lines to tank so usually a loose fitting or something if it leaks.

I would highly suggest trying to get hold of maintenance manual on the plane as it goes through a lot of detail.  Never enough, but will get you started.  I would just get part number of generator and google it. There are a few places that still work on them and you may even send it off and have it rebuilt.  There are also a number of circuits it runs through before getting to your panel and any one of those could cause problems.  So not necessarily your generator.

There is an under voltage relay in the nacelle that watch battery voltage and shuts down the entire system if the battery gets too low.  You can monitor generator at that point to see if it is putting out or if it is breaking down, then go from there.

Again, maintenance manuals while not perfect will make an impossible task at least breathable.

Good luck and sorry I couldn't help more,

Glenn
--glenn
You can't win an argument with an ignorant person,  they'll just drag you down to their level and beat you with experience.

Adam Frisch

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Re: 560A flap control
« Reply #2 on: July 09, 2018, 10:27:48 am »
I seem to recall the flap handle actuates a hydraulic valve via cables. The hyd valve is behind and below the co-pilots seat in the floor. But again, you'd have to look at a maintenance manual as I could be remembering wrong.
« Last Edit: July 09, 2018, 11:53:02 pm by Adam Frisch »
Slumming it in the turboprop world - so you don't have to.

Sparkskeywest

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Re: 560A flap control
« Reply #3 on: July 09, 2018, 11:34:29 am »
Thanks guys. Yes I have the maintenance manual. Accumulator is supposed to show pressure with a few pumps of the handle, and it does so we are assuming that it is full. Flaps still a mystery. Going to chk the flap cylinder in the left nacelle. No action when flaps put to detents, only when full down or up.

Sparkskeywest

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Re: 560A flap control
« Reply #4 on: July 09, 2018, 12:00:42 pm »
Here's the latest...flaps will adjust to a detent after flap handle is put in the full down position. After cylinder is activated, you can adjust the handle up to the desired position. That's the way this one works, but it doesn't sound right...comments please.