View Full Version : Engine failure on take-off
Nicholas49
6th Sep 2007, 18:01
I know that this question has most likely been asked before, but I have searched the forum and can't find it. I am hoping that there will be a friendly airline pilot here who will answer it and not shout at me.
If a TWO-engine passenger jet (a 737 for example) loses an engine immediately after take-off (within 0-10 seconds of leaving the ground), is there any chance of bringing it back down safely?
I'm sorry if the answer is bleedingly obvious, but I've not found it yet.
Performance Category 'A' aircraft (nearly all commerical 2-engine a/c) must be able to maintain specific rates of climb with an engine out. They can climb to a safe altitude (in fact probably towards 20,000ft, although it is very unlikely they would!) on the remaining engine. Normal procedures require landing at the nearest suitable airfiled.
Background Noise
6th Sep 2007, 18:53
This is a good example of what you describe and a well handled outcome: you tube engine failure(birdstrike) (http://www.youtube.com/watch?v=rQ2fqw0UWas)
The_Steed
6th Sep 2007, 19:47
Do you mean to bring it back down on the runway without actually flying away?
I think that for the reasons BOAC has detailed it's probably more dangerous to try that continuing the take off. I remember there being a video of a Ukrainian TU-134 trying to land immediately after take off and running off the end of the runway at some speed...
Nicholas49
6th Sep 2007, 19:58
No! I meant circling to land, not bringing it straight back down (surely even the longest runway would not be long enough). Sorry if this was not made clear.
BOAC and Background Noise: thank you very much for the explanation and video. Once again, youtube proves itself. Is that official airport footage?
If I can squeeze in a second question: would the autopilot be any help with this emergency or does it really require immediate intervention from the pilots?
PS If it fails before V2, is that still really not a problem?
chiglet
6th Sep 2007, 22:28
No! I meant circling to land, not bringing it straight back down (surely even the longest runway would not be long enough). Sorry if this was not made clear
It depends. At Manchester I have been on duty when a Dash8 lost an engine just after rotation. The circuit [and approach] was cleared, and he did a wide circuit, and landed about 5-6 mins later. A A320 rotated, lost an engine, and was on the ground, again in 5 mins or so, The TOM a/c went and sorted the a/c , probs because of weight.
PS If it fails before V2, is that still really not a problem?
V1 is the Stop/Go speed. That is the Maximum speed that the a/c can safely stop on the runway. Above the figure the pilot is commited to fly.
BTW As an ATCer, I stand to be corrected,:ok:
watp,iktch
An interesting example can be gained by looking at one particular middle east operator.
Years ago, one of their 737-200's had an engine fire just after liftoff....from a 15,000 foot runway.
The Commander elected to close throttles and land straight ahead, and deal with the engine fire on the ground.
The aircraft stopped at approximately the 9000 foot point on the runway, and the fire was extinguished.
No muss, no fuss.
However, the Commander was severely criticised by the respective fleet manager....until the Vice-President Flight Operations said (to the effect)....the Captain exercised the best judgement he thought, at the time, and he was there, no problems were encountered, so there will be no further discussion, as my name is on the door in the head office, and I am most definitely in charge...period.
And, not surprisingly, the respective Commander was back on flying statis very shortly thereafter.
In my personal opinion, the VP was quite correct.
Pilots are far too often criticised by folks who were not there at the time...a poor scenario.:uhoh:
Nicholas49
7th Sep 2007, 11:13
RE: V1/V2 - I am aware that V1 is the decision speed. Obviously, once you've passed V1 you have to go. But I said V2, which is the safe climb speed. My question is: what happens if your engine fails after V1 but before V2? Can you still climb away safely?
The impression I'm gleaning from recent posts is that the captain makes a decision on engine failure EVEN AFTER V1 as to whether to land without circling. Or have I got this wrong?
Incidentally, in the youtube video, can you tell who is the F/O and who is the captain? One guy is French and doesn't talk as much - is he the captain?
Or have I got this wrong? - basically yes. The standard procedure is to continue the take-off at or above V1. That said, it is always the Captain's call to deviate from this norm, although he/she needs to get it right if so and will be in conflict with published procedures leading to potential disciplinary actions.
As I said earlier, any Perf Category 'A' a/c should be able to continue at or above V1 and indeed, as you ask, below V2, although V2 is set as to be normally reached just after rotate.
chornedsnorkack
7th Sep 2007, 17:37
Performance Category 'A' aircraft (nearly all commerical 2-engine a/c) must be able to maintain specific rates of climb with an engine out.
Rates? Or gradients?
barit1
7th Sep 2007, 18:03
IIRC for certification, the engine-out climb GRADIENTS are:
2-engine a/c 2.4%
3-engine a/c 2.7%
4-engine a/c 3.0%
These are at Max TOGW and rated thrust on all remaining engines.
chornedsnorkack
7th Sep 2007, 18:11
They can climb to a safe altitude (in fact probably towards 20,000ft, although it is very unlikely they would!) on the remaining engine.
Why very unlikely? Especially when, say, not climbing well past 20 000 feet means going splat into the upper slopes of Illimani, well over 21 000 feet high? It has happened before, so it is a quite real concern...