Originally Posted by
Fareastdriver
I had a novel experience with a 332's undercarriage. On landing on a platform our attention was drawn to an oil leak coming from the starboard sponson area. I shut the aircraft down and investigated.
There was a small pool of hydraulic oil on the deck and the undercarriage had streaks of oil on it. I wiped everything in sight with absorbent paper and that cleaned it up. There was now no evidence of the whereabouts of the leak.
I got on the blower to engineering and they asked my to have another go at finding the leak as it would narrow down the bits they had to bring out. I went out and as there was still no sign of the origin I thought that I would put some pressure in the system.
I switched on the power, confirmed that there were three greens, inserted the emergency pump handle so as to manually pump some pressure into the system. It was quite stiff and after four or five pumps there was a commotion at the back of the aircraft as the undercarriage collapsed to the kneeling position.
I had always thought that an aircraft on the ground with three greens was sacrosanct; apparently not so.
The engineers knew about it; it was a dodge for lowering the aircraft to pack it into a 747 but nobody had told me or any other pilot I knew.
Now you all know.
You were famous for that one! Yes, if you put pressure onto the hydraulic locking valves, the hydraulic lock is released and with weight on the aircraft the gear will partially retract. Best not to be under the helicopter looking for leaks at the time!