More of a 'thank feck it never happened...'
I work for an aircraft ground support company and (as I'm kind of well spoken and polite) get to go onsite a lot of the time.

Few years back we got a contract in Beirut to service and test their aircraft jacks. As one of the only people in the company with a valid passport, the boss asked if I'd like to go - of course, having grown up with Beirut on the news due to the civil war going on, I jumped at the chance (I'm off the drugs now).

Anyhoo, we're working away quite well, then Tim decides he needs to visit the 'little Arab's room' so off he trots leaving me to pressure test this 50 tonnes capacity jack with NO instruction.

So I merrily jack it up to it's full height, then proceed to put the full 50 tonnes pressure onto it - any by hand using a small pump, that's no easy feat.

Tim comes back and says "what load did you put on it?"
"50 tonnes," says I with a proud smile. Cue a VERY strange look and Tim practically flew to undo the pressure release valve. When the jack was fully retracted, the only thing holding the 50kg, 1200mm long ram inside the jack was basically a circlip, albeit about 10mm thick, and this circlip was so out of shape from having this massive pressure* put onto it.

Now, we were working at the airport, and there was a MASSIVE troop barracks next door...can you imagine if that circlip had failed, resulting in a 1200mm, 50kg lump of steel hurtling through the hangar roof and probably into the barracks?

Actually, it did render the jack unusable, but the cost to replace was about £4000 so not that expensive I guess...

*In normal usage, the pressure would be on the top of the ram, not just pressurising against the cylinder collar.

Length: 120mm
Girth: 200mm
( snee held his breath since, Wed 31 Oct 2007, 13:32, 1 reply)

Eh?
50 tonne load on something with a 50 tonne capacity doesn't sound terribly panic inducing - what did I miss?
(misanthrope is so adjective he's verbing nouns!, Thu 1 Nov 2007, 9:42, closed)