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ssflying
22nd Aug 2011, 03:04
Just a hypothetical scenario,following a take off at vr we encounter an engine stall,after getting airborne and once safely established in climb we throttle back the affected engine to lets say idle ,at this point the eng stall characteristics cease and there have been no parameter exceedances.Do we now climb to our eng out acc altitude,clean up the aircrft and then do the Qrh eng stall paper checklist or do we call for it right away,complete the checklist,cleean up at eng out acc alt.:hmm:

Microburst2002
22nd Aug 2011, 10:08
in a sim check, you have to ask for the checklist after airplane is under control and 400 ft AGL. Retarding the thrust levers you can do that without checklist, of course.

in real life I bet that captain will simply advance the throttle slowly until stall recurs, then retard it again till it ceases. If this happens at eng idle, levelling off may be necessary to accelerate to green dot and report the situation to ATC. Otherwise, normal departure.

If stall was very severe or there were many before they ceased, I would keep lever retarded till MSA while carrying out the eng out procedure and informing ATC and then I would troubleshoot with the checklist being very conservative. Or simply return to the airfield.

rudderrudderrat
22nd Aug 2011, 11:28
Hi MB2002,

in a sim check, you have to ask for the checklist after airplane is under control and 400 ft AGL.
in real life I bet that captain will simply advance the throttle slowly until stall recurs,...
Why not do the same in real life and in the sim check?

If the engine was not delivering take off thrust - then perform the engine out profile as you will have eroded your normal take off profile. If the engine was stable at a reduced thrust setting, then keep it running whilst it is still helping.

Microburst2002
22nd Aug 2011, 16:02
In the sim they will tell you that you have to call for the checklist, rather than doing things on your own.
In real life Captain will not be influenced by the training captain's criticism, so he will disregard the checklist, or call for it much later.
it is just my opinion, coming from experience

rudderrudderrat
22nd Aug 2011, 20:57
Hi MB2002,

Thanks for being so honest.

If it was me - I'd fly the engine out profile (both in the sim or real life.) Once above 400 ft agl I'd ask for the "Eng 1(2) Stall QRH Checklist".
If the engine looked normal with the TL at idle, then ENG & Wing antiice on and advance TL slowly etc. iaw the check list.

3holelover
22nd Aug 2011, 21:37
If the engine looked normal with the TL at idle, then ENG & Wing antiice on and [etc]
Curious.... Could you explain that to me? The anti-ice part? I'd have thought the last thing you want to do is rob an iffy engine of air?
..also, If the aircraft has CFM-56's, I'd add, "if you know why it stalled" , etc...
My experience, with the CFM's in any case, has been that they won't stall without good reason, (they need a good cross wind, not just a bit, if they're in good shape) and it's the vbv's more often than the vsv's that mess up....
I think if they stall once, you're more likely to be better off considering them out of the game for this trip. I'd be surprised if they didn't repeat the performance if power was to be re-applied.

....Obviously you do what the books tell you to do... I'm just sort of offering a heads up...
If it's a CFM, and it goes BOOM, it ain't likely you'll have two good motors again today.
If it's a Pratt, you can probably carry on. ;)

rudderrudderrat
22nd Aug 2011, 22:13
Hi 3holelover,

Apparently the CFM engine will surge if the compressor gets overloaded (damaged compressor blades etc.) By taking more bleed air off with Eng & wing anti ice selected on, it's possible to reduce the compressor stall and permit the engine to operate at a reduced thrust setting.

If it was me - I'd rather have 1 & 3/4 engines than just one.

3holelover
22nd Aug 2011, 23:17
Interesting, thanks for that RRR... Yessir, I get the 1 3/4-is-better-than-1 notion!

ssflying
23rd Aug 2011, 01:31
Thanks,my only concern was the wing anti ice part,as i felt that we would be straining the remaining engine,on a hot day with a full flight(max tow).So i was wondering if it would be better to clean up at eng out alt and then carry out the check list.

rudderrudderrat
23rd Aug 2011, 08:34
Hi ssflying,

Since you have stopped the engine from surging by closing the TL, the engine is now technically "stable", so you may delay any further actions until you are clean and have MCT set.

ssflying
23rd Aug 2011, 09:12
Thanks for the clarification,does make one think in a clearer fashion

I-2021
23rd Aug 2011, 15:56
Just a hypothetical scenario,following a take off at vr we encounter an engine stall,after getting airborne and once safely established in climb we throttle back the affected engine to lets say idle ,at this point the eng stall characteristics cease and there have been no parameter exceedances.Do we now climb to our eng out acc altitude,clean up the aircrft and then do the Qrh eng stall paper checklist or do we call for it right away,complete the checklist,cleean up at eng out acc alt.

Hi,

the general idea behind is that a jet engine with such a high level of FADEC standard won't stall for minor problems, or at least there are very few chances that it will. If it happens in a situation as you described, my advice is to stick to the procedures that are designed for these situations, ie ENG STALL paper checklist. You will retard one engine at IDLE, therefore you can consider yourself being single engine until you may get back the engine to normal thrust settings, but you may not. In the mean time, at the back passengers and crew will probably hear loud bangs coming from the engine, so expect everybody to be a little scared, or at least to think what the hell is going on. Follow your single engine procedure and the QRH, put yourself in the legal side, that makes the difference between tea and biscuits with the chief pilot or a cold coffee with your local CAA. You come back safely, most probably with 2 engines, you applied all your procedures and you pass the ball to the maintenance.

Cheers.

I-2021
23rd Aug 2011, 16:10
In the sim they will tell you that you have to call for the checklist, rather than doing things on your own.
In real life Captain will not be influenced by the training captain's criticism, so he will disregard the checklist, or call for it much later.
it is just my opinion, coming from experience

Hi MB2002,

the SIM IS real life. The training captain's criticism comes if there is something wrong somewhere, and that's the point where you do not want to end up. Some old school old fashioned guys will probably behave as you say, but probably they're still back on their mind on how they use to do it on a DC-8 or a 742. Here we are talking about different material and everything happens for a reason. My advice is that whatever you will do in the SIM and whatever you will show the trainer, he will expect you to do it when you will be up there flying, that's the main and only reason of SIM sessions. If you apply your procedures and you are legal and safe you will have a friendly chat with flight safety ops in the worst scenario.

Cheers.

irishpilot1990
24th Aug 2011, 21:39
Above is the post of someone in a loco airline?? That needs to cover their ass...I am not disagreeing with your approach it still works.:ok: I would do the same.

However, sim and line trainer are not always correct. Airmanship comes BEFORE SOP. SOP's are not perfect, if they were, all companies would all use the same SOP, we dont.

Airmanship, aviate, navigate.....

then worry about ops:ok:

I-2021
25th Aug 2011, 11:27
Hi irishpilot1990,

Above is the post of someone in a loco airline??

No, I am not flying for a "loco airline", but I really don't see the point of your question.

That needs to cover their ass...

So you mean that pilots of "loco airlines" need to be careful towards safety and legal issues while pilots of national carriers and other can do whatever they like ? Interesting.

However, sim and line trainer are not always correct.

Hopefully.

Airmanship comes BEFORE SOP. SOP's are not perfect, if they were, all companies would all use the same SOP, we dont.

We are not actually talking about SOPs here, we are exactly talking about airmanship. Ssflying asked a question about how people here would react to an engine stall and people are giving their opinions, based on how they understand that situation and possibly based on their experience.

Airmanship, aviate, navigate.....

then worry about ops

Good quote of your last CRM recurrent training, but why don't you go a little bit more in depth of what you are stating ?

Cheers.

I-2021
1st Sep 2011, 08:29
Check this thread (http://www.pprune.org/middle-east/462458-emirates-777-incident-moscow.html#post6674192)