Gear extension problem(C421)

[kasulevictor]

Hi,
i recently pulled the emergency T handle on ground (C421) when the plane was parked at the hangers and pushed it back again.The following day,the gear failed to retract.What could be the problem? and ho can it be diagonised?

[avcraft]

The emergency extension system on a 421C blows high pressure nitrogen into the down ports of the undercarriage actuators. I would suggest it didn't retract due to 2000psi of nitrogen remaining in the down side of the hydraulic system preventing retraction... Are you the pilot of this machine? Did you read the Pilots Operating Handbook? The aircraft should not have been flown following this incident and will need to be jacked and retractions carried out to reset the shuttle valve and also have the nitrogen bottle recharged..

[goldeneaglepilot]

The obvious question is why pull the emergengcy extend on the ground? Is it like someone having the desire to set off a fire extinquisher to see if it works?

[pfflyers]

I'm a noob here, gotta make a first post somewhere right? As a retired A&P who'se actually worked on a couple 421's I've goota hope the OP pulled that handle by accident. To have allowed the a/c to be flown without being serviced is a little scary. I hope that guy doesn't work on or fly any planes I might ride in.