Originally Posted by
Oldlae
Roger bought three W/W Mk 10 from 32 Sqdn at Northolt, I put them on the register using the documentation for the civvy W/W WS55 Series 3. Since then the CAA considers them as different aircraft despite the MOD Parts Manual quoting both civvy and MOD part numbers.
I believe that civil registered WS-55 Whirlwinds had a second hydraulic system.