N1 - 0, N2 - 0 (737 argument with an instructor)
Totally agree with everything previously written, unless the instructor briefed something different, it is a Severe Damage situation.
In the company I work at, a few years ago they introduced a "feedback" channel where these incidences could be anonymously reported to the training department. they are also available to be read un edited by the pilot group. There is also the opportunity to comment on the feedback, so if it has happened to more than one crew, the others can add their weigh to it.
This has had a very positive effect in curbing the Rouge Instructor/Check captain behaviour.
In the company I work at, a few years ago they introduced a "feedback" channel where these incidences could be anonymously reported to the training department. they are also available to be read un edited by the pilot group. There is also the opportunity to comment on the feedback, so if it has happened to more than one crew, the others can add their weigh to it.
This has had a very positive effect in curbing the Rouge Instructor/Check captain behaviour.
It is incumbent on instructors and examiners to avoid negative training, or training in such a way that crews make assumptions simply because they are in a simulator. If the simulator has some non-realistic failure scenarios it's better not to go there. There are usually enough other failures in even quite basic simulators to test crew decision making.
A good examiner will work around simulator deficiencies in creative ways. For example, to reinforce that it is severe damage, and knowing that when the engine runs down vibration ceases (if that is what is in that particular simulator's tiny brain), introduce vibration preceding the actual engine 'failure' for long enough for the crew to recognise there is a serious problem. Or trigger fire warning before, simultaneous with, or soon after the failure. Then it's cut & dried what you expect them to do; no excuses for the wrong drill.
If you intend them to action a simple flame-out, at least create conditions that would be conducive to such an event, such as a contaminated runway and icing, or a fuel leak.
But back to the OP - as everyone here agrees, no rotation = severe damage.
A good examiner will work around simulator deficiencies in creative ways. For example, to reinforce that it is severe damage, and knowing that when the engine runs down vibration ceases (if that is what is in that particular simulator's tiny brain), introduce vibration preceding the actual engine 'failure' for long enough for the crew to recognise there is a serious problem. Or trigger fire warning before, simultaneous with, or soon after the failure. Then it's cut & dried what you expect them to do; no excuses for the wrong drill.
If you intend them to action a simple flame-out, at least create conditions that would be conducive to such an event, such as a contaminated runway and icing, or a fuel leak.
But back to the OP - as everyone here agrees, no rotation = severe damage.
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What’s more important Flying the aircraft or diagnosing the aircraft?
This length of this thread is exactly what Boeing is trying to avoid. Crews going heads down diagnosing what’s over and above the failure.
Fly the aircraft.
If vibration is distracting the crew from flying then take steps to stop the vibration.
and continue to
Fly the aircraft.
It’s been seen time after time crews diagnosing the problem, is it, is it not and next the aircraft is descending or not following the SID or being late to fly the engine out SID because the aircraft is no longer being flown accurately.
Worst case diagnose incorrectly and start messing with a good engine!
That last ones easy in the sim you programme simple indication faults on the good engine, zeros would be good and everyone gets sucked in diagnosing!
And no ones flying!
”So why did you get that GPWS warning?”
ahh because we were discussing wether it was severe or not.....
This length of this thread is exactly what Boeing is trying to avoid. Crews going heads down diagnosing what’s over and above the failure.
Fly the aircraft.
If vibration is distracting the crew from flying then take steps to stop the vibration.
and continue to
Fly the aircraft.
It’s been seen time after time crews diagnosing the problem, is it, is it not and next the aircraft is descending or not following the SID or being late to fly the engine out SID because the aircraft is no longer being flown accurately.
Worst case diagnose incorrectly and start messing with a good engine!
That last ones easy in the sim you programme simple indication faults on the good engine, zeros would be good and everyone gets sucked in diagnosing!
And no ones flying!
”So why did you get that GPWS warning?”
ahh because we were discussing wether it was severe or not.....
Last edited by Avinthenews; 20th Nov 2020 at 02:46.
So that is what I am sure of: N1 indicated 0, N2 indicated 0. I have been trained that this indicated an Engine Severe Damage, which made me call for a memory drill of the appropriate checklist.
Assuming the sim was on motion and therefore the motion is felt through the whole cabin. Suddenly N1 and N2 run to zero and aircraft yaws and rolls to the failed side. Is it a flameout or a severe damage event? Was there airframe vibration? If the answer was Yes then severe damage and use the appropriate non-normal QRH checklist.
If there was no vibration but N1 and N2 went to zero, then it is a basic engine flameout since there was a yaw and roll. The fact that N1 and N2 both went to zero could be an aberration in the fidelity of the simulator or a deliberate ploy by the instructor to test the pilot's diagnostic knowledge. The presence or absence of airframe vibration is the key to the actions to be taken.
The OP never mentioned anything about airframe vibration yet he did mention the simultaneous falling to zero reading of the N1 and N2. Nor did he mention anything about vibration indicator readings. .
In other words, he failed to include all the relevant items that could have assisted responders to this thread to make a meaningful assessment of the state of the failed engine. For example, did the cunning instructor select a staight forward engine failure (flameout) and simultaneously select a failure of the N1 and N2 instrument indications?
if indeed he did, could that scenario actually happen in real life? Answer: Almost certainly not.
On the face of it, and going by what the OP described, it seems the instructor may have introduced three totally unrelated non-normals at the same time. That was unfair and poor instructor technique.
With the cockpit indications provided by the instructor, coupled by the assumed absence of airframe vibration, the pilot under test should have diagnosed the fault as engine failure - not severe damage. This suggests the instructor was correct even though he used a sleight of hand by failing the N1 and N2 gauges simultaneously with the flameout.
Last edited by Centaurus; 20th Nov 2020 at 05:51.
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Assuming the sim was on motion and therefore the motion is felt through the whole cabin. Suddenly N1 and N2 run to zero and aircraft yaws and rolls to the failed side. Is it a flameout or a severe damage event? Was there airframe vibration? If the answer was Yes then severe damage and use the appropriate non-normal QRH checklist.
If there was no vibration but N1 and N2 went to zero, then it is a basic engine flameout since there was a yaw and roll. The fact that N1 and N2 both went to zero could be an aberration in the fidelity of the simulator or a deliberate ploy by the instructor to test the pilot's diagnostic knowledge. The presence or absence of airframe vibration is the key to the actions to be taken.
The OP never mentioned anything about airframe vibration yet he did mention the simultaneous falling to zero reading of the N1 and N2. Nor did he mention anything about vibration indicator readings. .
In other words, he failed to include all the relevant items that could have assisted responders to this thread to make a meaningful assessment of the state of the failed engine. For example, did the cunning instructor select a staight forward engine failure (flameout) and simultaneously select a failure of the N1 and N2 instrument indications?
if indeed he did, could that scenario actually happen in real life? Answer: Almost certainly not.
On the face of it, and going by what the OP described, it seems the instructor may have introduced three totally unrelated non-normals at the same time. That was unfair and poor instructor technique.
With the cockpit indications provided by the instructor, coupled by the assumed absence of airframe vibration, the pilot under test should have diagnosed the fault as engine failure - not severe damage. This suggests the instructor was correct even though he used a sleight of hand by failing the N1 and N2 gauges simultaneously with the flameout.
If there was no vibration but N1 and N2 went to zero, then it is a basic engine flameout since there was a yaw and roll. The fact that N1 and N2 both went to zero could be an aberration in the fidelity of the simulator or a deliberate ploy by the instructor to test the pilot's diagnostic knowledge. The presence or absence of airframe vibration is the key to the actions to be taken.
The OP never mentioned anything about airframe vibration yet he did mention the simultaneous falling to zero reading of the N1 and N2. Nor did he mention anything about vibration indicator readings. .
In other words, he failed to include all the relevant items that could have assisted responders to this thread to make a meaningful assessment of the state of the failed engine. For example, did the cunning instructor select a staight forward engine failure (flameout) and simultaneously select a failure of the N1 and N2 instrument indications?
if indeed he did, could that scenario actually happen in real life? Answer: Almost certainly not.
On the face of it, and going by what the OP described, it seems the instructor may have introduced three totally unrelated non-normals at the same time. That was unfair and poor instructor technique.
With the cockpit indications provided by the instructor, coupled by the assumed absence of airframe vibration, the pilot under test should have diagnosed the fault as engine failure - not severe damage. This suggests the instructor was correct even though he used a sleight of hand by failing the N1 and N2 gauges simultaneously with the flameout.
Have a read of the comments above. No rotation = severe damage. And if we must keep harping on about vibration, the checklist refers to airframe vibration so the engine vibration isn't hugely relevent.
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But, before making a decision on the actions I need to take, I studied the engine indications. So that is what I am sure of: N1 indicated 0, N2 indicated 0. I have been trained that this indicated an Engine Severe Damage, which made me call for a memory drill of the appropriate checklist.
Having had long experience at simulator training involving hundreds of engine non-normals including engine seizures, I cannot recall ever selecting on the instructor panel a deliberate engine seizure without the first indication to the flight crew being significant airframe vibration. Of course the seizure will eventually cause the N1 and N2 to fall to zero as the seizure takes effect. But without amplification by the OP of any other engine indications to back up his opinion the non-normal was a seizure, the discussion goes around in circles.
In the example given by the OP he seems to rely solely on the readings of two instruments N1 and N2 as proof of an engine seizure. The instructor disagreed and said it was an engine failure. After all, it was the instructor who "arranged" the the event so we should assume he knows which button he selected on his own panel.
Sorry mate but thats a load of rubbish
As with all situations it is the context which frames our judgement. Context is often limited in simulation, and furthermore by instructor application.
Time / duration of events add different meaning. A flameout can result in zero rotation, but takes time; quicker at low airspeed and/or with combinations of fan rotation but core stopped.
A fast, violent stop will be dominated by dissipation of energy. Engine vibration might not be as significant as potentially more disturbing and misleading aircraft vibration.
There may be no turbine vibs - because the component has departed the aircraft, but the noise and airframe vibration could be interpreted as an alternative scenario, e.g. stalling, depressurisation; thus attention could be on stall avoidance or not over-stressing - first fly the aircraft.
Alternatively a flame out could be unnoticed until the oil pressure light comes on, both engines being at idle during a fast descent which maintains rotation; each type and situation has unique characteristics, as does human reaction - pilot and instructor - who's point of view.
Consider the objectives of training; safety. Awareness and actions (SOPs) are never perfect, but the outcome should be sufficiently safe, … and always an opportunity to learn, both crew and instructor.
Time / duration of events add different meaning. A flameout can result in zero rotation, but takes time; quicker at low airspeed and/or with combinations of fan rotation but core stopped.
A fast, violent stop will be dominated by dissipation of energy. Engine vibration might not be as significant as potentially more disturbing and misleading aircraft vibration.
There may be no turbine vibs - because the component has departed the aircraft, but the noise and airframe vibration could be interpreted as an alternative scenario, e.g. stalling, depressurisation; thus attention could be on stall avoidance or not over-stressing - first fly the aircraft.
Alternatively a flame out could be unnoticed until the oil pressure light comes on, both engines being at idle during a fast descent which maintains rotation; each type and situation has unique characteristics, as does human reaction - pilot and instructor - who's point of view.
Consider the objectives of training; safety. Awareness and actions (SOPs) are never perfect, but the outcome should be sufficiently safe, … and always an opportunity to learn, both crew and instructor.
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The OP description of what he looked at in deciding the action to take is too simplified. As Centaurus noted there was no mention by the OP of any other engine parameters. The whole subject under discussion is not worth arguing about until the OP provides more detail on what else he saw other than the readings of two gauges, the N1 and N2.
Having had long experience at simulator training involving hundreds of engine non-normals including engine seizures, I cannot recall ever selecting on the instructor panel a deliberate engine seizure without the first indication to the flight crew being significant airframe vibration. Of course the seizure will eventually cause the N1 and N2 to fall to zero as the seizure takes effect. But without amplification by the OP of any other engine indications to back up his opinion the non-normal was a seizure, the discussion goes around in circles.
In the example given by the OP he seems to rely solely on the readings of two instruments N1 and N2 as proof of an engine seizure. The instructor disagreed and said it was an engine failure. After all, it was the instructor who "arranged" the the event so we should assume he knows which button he selected on his own panel.
An interesting and informative thread spoilt by a rude remark civf88
Having had long experience at simulator training involving hundreds of engine non-normals including engine seizures, I cannot recall ever selecting on the instructor panel a deliberate engine seizure without the first indication to the flight crew being significant airframe vibration. Of course the seizure will eventually cause the N1 and N2 to fall to zero as the seizure takes effect. But without amplification by the OP of any other engine indications to back up his opinion the non-normal was a seizure, the discussion goes around in circles.
In the example given by the OP he seems to rely solely on the readings of two instruments N1 and N2 as proof of an engine seizure. The instructor disagreed and said it was an engine failure. After all, it was the instructor who "arranged" the the event so we should assume he knows which button he selected on his own panel.
An interesting and informative thread spoilt by a rude remark civf88
The analysis going on in this thread really concerns me. The simulator session regarding engine failure symptoms should not be ad-hoc. Follow the FCOM. At least that can be changed to recognize important new techniques, As some have said Fly the Aircraft First. Don't try and interpret beyond what you are trained unless you run out of options in flying the aircraft.
If there is general agreement that the FCOM has missed something important, let the experts fix it.
If there is general agreement that the FCOM has missed something important, let the experts fix it.
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No vibrations (in the sim),
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This failure is a function of the radial drive shaft rupture.
If You think a high bypass turbofan engine flying at 140+ kt can go from 90+ % N1 or N2 to ZERO in a matter of a few seconds without damage then I guess we are not on the same page, but it is always good to discuss and learn more.
If You think a high bypass turbofan engine flying at 140+ kt can go from 90+ % N1 or N2 to ZERO in a matter of a few seconds without damage then I guess we are not on the same page, but it is always good to discuss and learn more.
What’s more important Flying the aircraft or diagnosing the aircraft?
This length of this thread is exactly what Boeing is trying to avoid. Crews going heads down diagnosing what’s over and above the failure.
Fly the aircraft.
If vibration is distracting the crew from flying then take steps to stop the vibration.
and continue to
Fly the aircraft.
It’s been seen time after time crews diagnosing the problem, is it, is it not and next the aircraft is descending or not following the SID or being late to fly the engine out SID because the aircraft is no longer being flown accurately.
Worst case diagnose incorrectly and start messing with a good engine!
That last ones easy in the sim you programme simple indication faults on the good engine, zeros would be good and everyone gets sucked in diagnosing!
And no ones flying!
”So why did you get that GPWS warning?”
ahh because we were discussing wether it was severe or not.....
This length of this thread is exactly what Boeing is trying to avoid. Crews going heads down diagnosing what’s over and above the failure.
Fly the aircraft.
If vibration is distracting the crew from flying then take steps to stop the vibration.
and continue to
Fly the aircraft.
It’s been seen time after time crews diagnosing the problem, is it, is it not and next the aircraft is descending or not following the SID or being late to fly the engine out SID because the aircraft is no longer being flown accurately.
Worst case diagnose incorrectly and start messing with a good engine!
That last ones easy in the sim you programme simple indication faults on the good engine, zeros would be good and everyone gets sucked in diagnosing!
And no ones flying!
”So why did you get that GPWS warning?”
ahh because we were discussing wether it was severe or not.....
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An interesting and informative thread (I use that loosely) which had come to a valid consensus. Only for someone who had not bothered reading any of it to start repeating the same points which had been successfully argued against above.
A simultaneous N1 / N2 instrument failure
A simultaneous N1 / N2 instrument failure
Ladies! Please!
In the rush to find a “wrong” answer, is it possible that both diagnoses have some merit and there is not 100% certainty because of lack of detail? Faced with a completely seized engine on both rotors, it’s not going to run again until it’s left the repair shop, so there is no harm whatsoever in doing the Severe checklist. Being pedantic you could argue that it was just a rundown(!) without vibration so it just needs securing.
Both are points of view and both could be “right” but, in real life, what would you do if an engine failed (and you know this because of the yaw and loss of performance) and even though there is no vibration N1 & N2 have gone to zero over a short time interval? Would you really go “oh yes, definitely fine, let’s start it back up later”? I think I’d be checking under the wing to see how much of it was left...
In the rush to find a “wrong” answer, is it possible that both diagnoses have some merit and there is not 100% certainty because of lack of detail? Faced with a completely seized engine on both rotors, it’s not going to run again until it’s left the repair shop, so there is no harm whatsoever in doing the Severe checklist. Being pedantic you could argue that it was just a rundown(!) without vibration so it just needs securing.
Both are points of view and both could be “right” but, in real life, what would you do if an engine failed (and you know this because of the yaw and loss of performance) and even though there is no vibration N1 & N2 have gone to zero over a short time interval? Would you really go “oh yes, definitely fine, let’s start it back up later”? I think I’d be checking under the wing to see how much of it was left...
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But after that, I was interrupted by the instructor – stating that he gave me a simple engine failure.
Regardlees what the N1 and N2 readings were (either instantaneously or some time later), if we are to believe the OP username Emirares787 when he writes that the instructor told him he had given him a simple engine faillure, then readers of this saga must accept the instructor did just that. Even the copilot diagnosed an engine failure. The PF obviously disagreed with the copilot assessment. Fine - that is his privilege.
QUOTE.....in real life, what would you do if an engine failed (and you know this because of the yaw and loss of performance) and even though there is no vibration N1 & N2 have gone to zero over a short time interval? Would you really go “oh yes, definitely fine, let’s start it back up later”? I think I’d be checking under the wing to see how much of it was left...[/QUOTE]
Precisely! Pod mounted engines have been known to completely depart the wing. That would certainly cause the N1 & N2 gauges to be somewhat confused. Of course in the real machine there would be all sorts of other unpleasant cues, but older simulators will lack these. The OP mentions this was a B737 Classic sim, so it would not be 'state of the art'.
Centaurus/Sheppey may have been exposed to so much simulator he is only looking at it from the perspective of an instructor panel with a limited portfolio of failure modes. That's for the instructor to work around, not the candidate. Neither should the candidate be expected to read the instructor's mind to determine what is required; however it is certainly part of the instructor's job to look at what cues are being presented in the candidate's seat, and whether the actions taken are reasonable - not what buttons have been pressed on the IOS !
When doubt exists, a pilot under check should never be pinged for doing a worst case checklist.
Save the cheaper options for discussion during line checks.
Precisely! Pod mounted engines have been known to completely depart the wing. That would certainly cause the N1 & N2 gauges to be somewhat confused. Of course in the real machine there would be all sorts of other unpleasant cues, but older simulators will lack these. The OP mentions this was a B737 Classic sim, so it would not be 'state of the art'.
Centaurus/Sheppey may have been exposed to so much simulator he is only looking at it from the perspective of an instructor panel with a limited portfolio of failure modes. That's for the instructor to work around, not the candidate. Neither should the candidate be expected to read the instructor's mind to determine what is required; however it is certainly part of the instructor's job to look at what cues are being presented in the candidate's seat, and whether the actions taken are reasonable - not what buttons have been pressed on the IOS !
When doubt exists, a pilot under check should never be pinged for doing a worst case checklist.
Save the cheaper options for discussion during line checks.
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When You have spent decades in the sim You have a very wide view of the spectrum plus You probably have done TONS of snag clearances in the SIM.
Anyway I agree there is not much left for discussion, it was very interesting so far with different point of view and lots of food for thoughts !
When doubt exists, a pilot under check should never be pinged for doing a worst case checklist.
There is a tendency to drift towards the unquestioning following of SOPs and that there is only one way (my way) of dealing with an issue that gives a positive outcome. There are very, very few circumstances that require immediate action with no real time to think about it first (high-speed RTO comes to mind). Although an engine failure seems like a simple thing with clearly defined actions as a result, even this is not as straightforward as it seems.
One of our training documents is a 40-page interactive book covering some of the engine failure possibilities and ways to deal with them. OK, you say, but to keep things simple, the manufacturers have distilled all that into a few choices that are simple to action in a time of high workload. Absolutely true, I say, but you can still end up in a cul-de-sac if you rush in blindly without due mental process. Imagine you go through a flock of birds after takeoff (does happen) and there are a few pops but the engines are still running. Shortly after that you notice the EGTs are high on both and then there is a fire warning on one engine. SOPs say to shut it down and fire the bottle but is that wise *right now*, especially as it is still producing thrust? What are we going to do if we get a fire warning on the remaining engine?
I’m sure everyone reading this would pause and reassess the situation, should it happen to them, but if you continually beat people over the head to follow SOPs no matter of any indication to the contrary, it might lead to a sub-optimal outcome. The fate of the French Concorde was sealed when a running engine was shut down due to a fire warning, leaving not enough thrust to stay airborne. Yes, it was probably going to crash anyway but that action made it a certainty.
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When in doubt...
If you're unsure if it was a "simple" flameout or a severe damage, then treat it as severe damage.
It's best to land with a good engine shutdown than to try and re-start an engine with severe damage.
IMHO 0 N1 is a good sign of a seized engine. N2 may slowly wind down to 0 at low airspeeds, but N1 should always be rotating simply by windmilling.
It's best to land with a good engine shutdown than to try and re-start an engine with severe damage.
IMHO 0 N1 is a good sign of a seized engine. N2 may slowly wind down to 0 at low airspeeds, but N1 should always be rotating simply by windmilling.