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Old 13th Mar 2008, 23:01
  #986 (permalink)  
B47
 
Join Date: Dec 2002
Location: Yorkshire
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Graviman,

Just checked my MM for you. Yes, there's a full schematic of the hydraulics plus a full 3D line drawing of the complete system. Don't quote me on this as I'm the owner of a pre-hydraulics Astro so I can't check the actual ship, but there isn't a distribution block (as on my 35hp compact tractor...). The reservoir supplies equal pressure to the three servos. 450-500 psi that's in excess of needed for normal control forces, constant return via pressure relief valve. Elastic cord balances the opposite forces. Electrics only needed to turn system off i.e. fail safe in electrical failure. Very simple system which when you look at the complexity of the electric trim system, apart from a little more weight, makes you wonder why Frank R never went for hydraulics in the first place.

PM me if you wish and I'll send you more detail.
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