The Vulcan XH558 & General Aviation Thread

[mtskull]

...and that Spitfire was already having engine runs today, yay! Just a few dented panels, but fortunately, no shock loading of the engine then.

I haven't seen a video of the incident but, judging by the state of the propellor blades, it appears that it was windmilling rather than under power when the prop struck.

[Renegadenemo]

cause was a seized hydraulic pump that fractured the quill shaft at the design weak spot.

We know all about those having had to re-engineer the hyd' pump drive for the Orph' to get our water brake working but surely the Sea Vixen has a pump on each engine and accumulators and all that gubbins? How can a single failed pump cause an accident like that?

[Renegadenemo]

that'll need repainted before it goes back on...

[Renegadenemo]

Apparently it does have two pumps as you'd expect, and when the Green one failed, the Red one failed to supply pressure, likewise the RAT.

Would suggest that either the failed pump took something crucial with it when it gave up or it didn't fail at all and the problem lies elsewhere. Keep us posted.
I know it's a smidge off-topic but we have a case going on here at the moment where a surgeon inserted a replacement aortic valve in a patient the wrong way around so instead of opening when it should have it slammed shut and destroyed her heart. Bad day at the office, was that.
http://www.bbc.co.uk/news/uk-england-tyne-40332761

[mtskull]

Apparently it does have two pumps as you'd expect, and when the Green one failed, the Red one failed to supply pressure, likewise the RAT.

I'm very surprised that there isn't a last resort manual pump or, at very least, a cable or linkage system by which the pilot could directly release the uplocks and residual pressure so that the gear free falls down. I don't think I have ever flown an aircraft fitted with retractable undercarriage that didn't have one or the other.
Then again, that is military, rather than civil, aviation philosophy at work: Have a malfunction, abandon the aircraft and the taxpayer buys you a new one. Doesn't work so well for a rare, preserved historic aircraft, though.

[Richie]

You then run the risk of a partial drop.. i.e. One leg dropping and the other two staying up.


Then your in a world of hurt. In my most humble opinion better to belly land than try with one leg lowered.

[mtskull]

You then run the risk of a partial drop.. i.e. One leg dropping and the other two staying up.


Then your in a world of hurt. In my most humble opinion better to belly land than try with one leg lowered.

Maybe so in some tailwheel aircraft but with a tricycle configuration, received wisdom has always been that it is better to land on one or two legs than none at all; sufficient control to keep wings, noses, etc. from contacting the ground can be maintained until quite a low speed, which is certainly preferable to allowing parts of the aircraft that are not designed for the purpose to contact the ground at touchdown speed.

Back in the 1990's when I worked for the now-defunct Manx Airlines, there was a spate of incidents involving the BAe ATP fleet: If I remember correctly, there was one nosegear collapse, one nosegear failed to extend and one main gear partial extension. They all landed on what remained, without casualties and without major structural damage.

[Renegadenemo]

Clearly it can happen even on modern commercial airliners.

https://www.youtube.com/watch?v=vKo4Eee7V3s

[mtskull]

Clearly it can happen even on modern commercial airliners.

https://www.youtube.com/watch?v=vKo4Eee7V3s

I had to google that one; they made a nice job of the landing. A pity about the popped circuit breaker which prevented the alternate landing gear system from working; some airline managers I know would have crucified the Captain for not spotting that and re-setting it.
I would be very interested to know whether they modified the emergency checklist in the aftermath, to read something like:
Gear fails to extend -operate alternate gear extension -does gear extend? -no -check circuit breakers nos. xxx & yyy....

[Renegadenemo]

I would be very interested to know whether they modified the emergency checklist in the aftermath

Hard to imagine that they wouldn't but humans will still find a way to scupper themselves even with a checklist. There was the Kegworth accident where, had they bothered to read it properly and not thrown their aircraft at the ground, they'd likely have picked up that they'd shut down the wrong engine. Contrast that with Swissair DC10 that caught fire and they sat up there reading checklists instead of throwing it at the ground until they burned to death...

Great friend of mine is the 737 fleet manager for a major airline and a training captain too. He's been in all sorts of scrapes and is always first to fly new routes ahead of scheduled operations but he went completely to pieces when his wife fell pregnant because... there was no checklist!
I had him send the complete 73 checklist from ground checks to startup, takeoff, cruise, landing and shutdown and rewrote it to cover pregnancy and childbirth whereupon there's a massive depressurisation and a new crew member arrives. It described ventral tanks full to bursting and don't even go there where flaps are concerned but it also contained much useful info like, find out where the nearest florists is, pack an overnight bag and take change for parking meters and coffee machines. He loved it and settled right down.