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malc4d
22nd Feb 2009, 14:48
Morning..

Does anyone know what the pilot side squat switch controls, (has six wires )also the passenger side squat switch. (has 4 wires)..?

How do l know if it has unfeathering accumulators...? p.o.h. says ' if fitted'


Malc

stevef
22nd Feb 2009, 15:58
Can't say as I've heard of a 'swat' switch before. Squat switch perhaps? If so, it's a 'weight on' switch that protects the landing gear from being raised whilst the aircraft is on the ground.
I've not worked on a Duchess for a long time but you'll find two types of feathering accumulators on light aircraft.
One is a long tube about 15 inches long and maybe 3 inches in diameter that is generally mounted towards the rear of the engine on a metal plate. The nitrogen charge is around 90psi depending on temperature.
The other type is more obvious as it's part of the propeller hub. If the spinner is two-piece (the forward part held on with three screws), there'll be a charging valve underneath. According to temperature, the pressure will be around 20 psi.

malc4d
22nd Feb 2009, 20:07
Thanks for the reply.
I was hopeing someone would say ..from no. 344 onwards or somthing like that..........guess i'll ask the mec tomorrow......:O

malc4d
2nd Mar 2009, 23:43
Ok. seems 'our ' Duchess has unfeathering accumulators........... Pitot pressure stops gear retraction on the ground..........:ok:
Now what do the squat switches do............:confused: