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Engine relight!!

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Old 20th Feb 2007, 17:15
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Engine relight!!

http://www.youtube.com/watch?v=V06LBgfuxgA&NR

Anyone explain why the engine apparently self re-lit?
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Old 20th Feb 2007, 18:58
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because jets do that. they are designed to relight if they flameout.
magic called fadec or eec
cheers
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Old 21st Feb 2007, 07:27
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Impressive video....landed ,offloaded the pax and tried to takeoff again...ups,it was in the water....
What kind of pilots were flying that plane...landed with high tailwind,wet runway ,ended in water,and forgot to even shutdown the engines...?
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Old 21st Feb 2007, 08:03
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Ironicly enough, the registration number on the replacement aircraft is
OY-WET


http://www.airliners.net/search/phot...nct_entry=true

Last edited by Capt. Inop; 21st Feb 2007 at 08:17.
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Old 21st Feb 2007, 09:44
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automatic re-light - definetly maybe.
on airbus they do, or at least can if the atari detects a flameout. on boeing? no way, because the whole relight thing requires smart design. on citation? don't know and don't believe. i heard the engine control got a short circuit in the water and did a restart....
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Old 21st Feb 2007, 15:53
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Hmmm, Boeing 744s do have auto-relight - well it's an option on the Rollers anyway - and I assume that all later models do too.


VnV
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Old 21st Feb 2007, 18:40
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But didn't it take something like 5 minutes before the engine started again?

That's not relight lads. That's just weird.

Relight is supposed to instantly (more or less) relight an engine that has suffered flame out. The idea being that the flame will be recovered before the engine spools down below a critical level. If the engine has stopped altogether (as it must have in this video) then all the cracking ignitor plugs on the planet won't get it going again. You need it to turn first......
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Old 22nd Feb 2007, 06:56
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OK, I was commenting on the previous post rather than the link (being at work it is difficult to view it without someone taking exception!). When I am home I will take a proper look at the whole thing, and perhaps check my design notes on the N1/N3 thresholds for igniters and fuel on.

VnV
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Old 22nd Feb 2007, 08:42
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Paddy , that was kind of my point. I know all about auto relight but in this case it had been completely shut down and then appears to just start up all by itself!
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Old 22nd Feb 2007, 13:50
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That is an amazing video!

As has been said, the engine suddenly spooling up seems to have nothing to do with relight/auto-ignition. Maybe it's just a result of the impact from the overrun and going into the water. To remember the "fuel shut off" switches as you are heading for the water (or before evacuating) would take a fairly good aviator (as can be gathered from the video, the picture below(?) and the accounts from the accident - this was not the case...)

Some questions and observations come to mind;
Why is one of the women getting out topless(!)?

[pure speculation - I know...]Wouldn't the first "fly-by"/pattern have to be pretty spectacular for the guy to get his camcorder out, run towards the runway and say "we got a nutball trying to land" (or maybe just the fact that any jet was coming in for landing was enough?).

As I was watching the video and saw the paint scheme and the shots of the people getting into the boats I came to think of a picture that someone sent me a while ago (I managed to find it on airliners.net):

http://www.airliners.net/open.file/0171522/M

I had a good laugh when I realized that it IS the same operator!
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Old 25th Feb 2007, 16:07
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Jet ignition

All jets have 3 position ignition systems.
"Start" (for just that!), "Continous" and Off.
Normal procedures dictate "Continous" be selected
prior to landing. Start is a high energy ignition
and Continous is much lower as would be required to light
off a hot spinning engine.
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Old 25th Feb 2007, 16:51
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All jets have 3 position ignition systems.
"Start" (for just that!), "Continous" and Off.
Normal procedures dictate "Continous" be selected
prior to landing. Start is a high energy ignition
and Continous is much lower as would be required to light
off a hot spinning engine.
Eh, grand so.....

Oh and my jet doesn't say have continuous ignition on for landing.

......what was the point of your post again?
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