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ENG Failure Strategy

Old 10th Jul 2019, 19:14
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ENG Failure Strategy

2 strategies for ENG Failure in CRZ for A320
1. Standard.
2. Obstacle.

Recently Training Captain was suggeting Green Dot should be the intial speed selection in all circumstances of ENG Failure in CRZ. Rationale was aircraft will maintain ALT until speed reduces to Green Dot, and then slow descent at Green Dot. This will give you time. Time for a PAN/Mayday call in busy airspace, time to think about options. Also as Company policy is not to restart an engine unless the cause of the failure can be determined, there was no rush to descend at 300kts/M.78.
Also as we have TCAS, remain on route if there is no conflicting traffic, as a deviation may put you in conflict with traffic on other airway routes. Flying in busy European Airspace, both points seem logical to me.

Next day, new training Captain, said NO. Immediately to 300kts/M.78 and turn off the airways to the right by 30 degrees. Exactly as the Manual says.

Except the Manual doesn't say that. Jepps advise to remain on the airways until at least advising ATC. The turn off the airways is a contingency in the event that no communciation can be established and only to descend by 500ft or 1000ft. Also different States have different Contingency procedures, and my brain is not capable of remembering them, and when to apply them.
And the speed, because the engine will try to restart automatically, so needs to be at 300kts to do that.

I agree with the logic of option 1, but the FCOM does say 300/M.78. So, who is right, what is wrong and does it really matter in the actual event?
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Old 10th Jul 2019, 19:52
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Originally Posted by IBE8720 View Post
2 strategies for ENG Failure in CRZ for A320
1. Standard.
2. Obstacle.

Recently Training Captain was suggeting Green Dot should be the intial speed selection in all circumstances of ENG Failure in CRZ. Rationale was aircraft will maintain ALT until speed reduces to Green Dot, and then slow descent at Green Dot. This will give you time. Time for a PAN/Mayday call in busy airspace, time to think about options. Also as Company policy is not to restart an engine unless the cause of the failure can be determined, there was no rush to descend at 300kts/M.78.
Also as we have TCAS, remain on route if there is no conflicting traffic, as a deviation may put you in conflict with traffic on other airway routes. Flying in busy European Airspace, both points seem logical to me.

Next day, new training Captain, said NO. Immediately to 300kts/M.78 and turn off the airways to the right by 30 degrees. Exactly as the Manual says.

Except the Manual doesn't say that. Jepps advise to remain on the airways until at least advising ATC. The turn off the airways is a contingency in the event that no communciation can be established and only to descend by 500ft or 1000ft. Also different States have different Contingency procedures, and my brain is not capable of remembering them, and when to apply them.
And the speed, because the engine will try to restart automatically, so needs to be at 300kts to do that.

I agree with the logic of option 1, but the FCOM does say 300/M.78. So, who is right, what is wrong and does it really matter in the actual event?
Hi, it's been a little while and a few types since I was on the bus (A330/A340) - I/We used to teach, as a demo, why there was no rush or the need for flashing hands and that if you wanted to you didn't need to do anything - as I remember it the aircraft will maintain altitude and the speed will reduce - I'm sure it was a much lower speed than green dot (top of red?) when the autopilot would disconnect (which, of course, it doesn't really do) and the aircraft would descend at that lower speed and, yes, depending on weight and altitude you had a great deal of time to advise ATC and safely negotiate a lower altitude. It really is no drama at all (unless you're on fire).

Your first training captain is absolutely correct about staying on the route etc - you go diving off and down and you could well hit another aircraft - what's the rush to try a restart which is usually a waste of time (this is usually done after you order a coffee). Most engineering departments will say no thanks" (unless it's an emergency you should have a chat to them before a restart) - they don't want any damage (secret for you - unless it's an engine stall most jet engines do not restart). After you've had your coffee, engineering have said yes, you've had a chat about continuing to destination or diverting then you can check the engine start envelope.

As you talk to the controller squawk 7700 - it is the best thing you can do (same on a depress) ...... with the complex, multi-layered airspace throughout Europe this is the best way to immediately get the message to all controllers nearby - 7700 appears on their screens and they can clear traffic from below - quicker than your current controller can talk to them and advise.

Your info re. contingency procedures is correct.

They can't cover everything that could ever happen to you in an ops manual so they'll give you a basic procedure that works and the rest is why they pay you the big bucks. You need to operate the aircraft and select the solution that fits your situation (one size does not fit all).

I should remember the Airbus info in better detail after three engine failures on it (and another 9 on other stuff) but getting old !

Best


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Old 11th Jul 2019, 05:52
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Originally Posted by IBE8720 View Post
2 strategies for ENG Failure in CRZ for A320
1. Standard.
2. Obstacle.

Recently Training Captain was suggeting Green Dot should be the intial speed selection in all circumstances of ENG Failure in CRZ. Rationale was aircraft will maintain ALT until speed reduces to Green Dot, and then slow descent at Green Dot. This will give you time. Time for a PAN/Mayday call in busy airspace, time to think about options. Also as Company policy is not to restart an engine unless the cause of the failure can be determined, there was no rush to descend at 300kts/M.78.
Also as we have TCAS, remain on route if there is no conflicting traffic, as a deviation may put you in conflict with traffic on other airway routes. Flying in busy European Airspace, both points seem logical to me.

Next day, new training Captain, said NO. Immediately to 300kts/M.78 and turn off the airways to the right by 30 degrees. Exactly as the Manual says.

Except the Manual doesn't say that. Jepps advise to remain on the airways until at least advising ATC. The turn off the airways is a contingency in the event that no communciation can be established and only to descend by 500ft or 1000ft. Also different States have different Contingency procedures, and my brain is not capable of remembering them, and when to apply them.
And the speed, because the engine will try to restart automatically, so needs to be at 300kts to do that.

I agree with the logic of option 1, but the FCOM does say 300/M.78. So, who is right, what is wrong and does it really matter in the actual event?
There are a few aspects that need to be addressed. FCOM gives you aircraft operational procedures that need to be followed for optimum results in terms of range or ceiling.The second is the applicable airway procedures which have to be followed to the possible extent. I can't remember will not do. Like in China it's mandatory to turn right 30 and fly parallel only five miles.
Now technical details. When engine failure is recognized by FADEC it tries auto relight for 30secs. If it doesn't succeed then there is no more relight attempt and auto relight is switched off.
When it comes to execution of the procedure it is true that it's not like EMER DES where you want to descend as soon as possible but rather opposite of that, it's a reluctant descent because you cannot maintain level. The speed drop is gradual. So first check from MCDU that the ceiling is lower otherwise just put the thrust levers to MCT and keep ATHR on, no need to do anything else as you will remain on the airway, just inform ATC. If there is need to descend then disconnect ATHR in MCT. Inform ATC and take action as per airway procedure turn or continue. Set the strategy speed, HDG if required and the ceiling. Descent can be initiated last but there's no virtue in going to GD if air way instructions are received and being followed. Manual auto relight may be attempted in the relight envelope.
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Old 11th Jul 2019, 07:50
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IBE8720 Check what exactly the FCOM says about the STANDARD strategy and what is the right technique to make the FCU selections.

Chances are that you are not the first facing this dilemma and the answers may actually already be in place. Is it possible to observe the wise guidance of the first instructor, and at the same time obey the FCOM as demanded by the other one?

Come back and tell, we share opinions then.

There should really be 4 strategies
a) obstacle - green dot for minimum altitude loss
b) LROPS - fixed high speed for increased planning distance CRZ OEI
c) restart - optimum relight speed
d) the normal one

Funilly, the D) is not defined or described by Airbus in any way. The various bits and pieces from the other 3 might not be best suited for the simple enroute diversion plan.

I also hear that if an engine quits, another reason not to start is to keep the FADEC memory logs intact for investigation. A new start might wipe them out. It is stretched thinking ... but?

A small thing at last, ​​​ I would politely ask we keep the "7700 x Keep the assigned code" debate for later. Going to read Wiki on the Streisand effect now.
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Old 11th Jul 2019, 07:54
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IBE..You have to keep an open mind is the answer because both trainers are correct, one prefers to default to the obstacle strategy, the other to standard. Your company policy manual or fleet office should provide guidance on which method is preferred but as the other experienced posters have said, unless you have an uncontrollable fire there’s no rush. Chances are the airspace is congested if you’re in Europe so diving down is only going to increase your workload, threats and thus stress...which is why it’s generally the GD strategy for me.
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Old 11th Jul 2019, 08:19
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I think the name of each strategy is quite clear.
1 Obstacle strategy (to be used in case of engine failure, if the EO crz level is affected by en route obstacles).
2 ETOPS strategy (to be used in order to achieve ETOS certification).
3 Standard strategy (to be used whenever the 2 previous strategies are not applicable).

Standard strategy ensures the a/c will remain within the windmilling relight envelope and supports the automatic relight attempt.

Think about the scenario: by applying obstacle strategy, you prevent the automatic relight attempt performed by the FADEC during the first seconds after the engine failure.... and later on you read the ECAM "if no damage: engine relight consider". Imagine your final altitude in case of successful engine relight after applying the Engine failure / engine relight QRH procedure VS final altitude in case of successful automatic relight procedure.

In addition in case of IAE engines, you need at least 280 kts to prevent "core lock" situations as explained in an other procedure.

When i discuss the scenario with my F/Os while crossing the alps (a/c is able to clear the obstacles by at least 6000ft in case of engine failure), i ask them if for example they feel more comfortable to encounter turbulence while flying green dot speed VS speed of standard strategy. I also ask if they prefer to extend the time overflying the high altitude sector by reducing the speed.
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Old 11th Jul 2019, 09:58
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Think about the scenario: by applying obstacle strategy, you prevent the automatic relight attempt performed by the FADEC during the first seconds after the engine failure.
Nothing of that sort happens as I mentioned earlier autorelight attempt is made immediately by FADEC once sub idle N1 is detected by switching on both igniters and it continues only for 30seconds. If unsuccessful the ignition is switched off.
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Old 11th Jul 2019, 12:07
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Originally Posted by IBE8720 View Post
2 strategies for ENG Failure in CRZ for A320
1. Standard.
2. Obstacle.

Recently Training Captain was suggeting Green Dot should be the intial speed selection in all circumstances of ENG Failure in CRZ. Rationale was aircraft will maintain ALT until speed reduces to Green Dot, and then slow descent at Green Dot. This will give you time. Time for a PAN/Mayday call in busy airspace, time to think about options. Also as Company policy is not to restart an engine unless the cause of the failure can be determined, there was no rush to descend at 300kts/M.78.
Also as we have TCAS, remain on route if there is no conflicting traffic, as a deviation may put you in conflict with traffic on other airway routes. Flying in busy European Airspace, both points seem logical to me.

Next day, new training Captain, said NO. Immediately to 300kts/M.78 and turn off the airways to the right by 30 degrees. Exactly as the Manual says.

Except the Manual doesn't say that. Jepps advise to remain on the airways until at least advising ATC. The turn off the airways is a contingency in the event that no communciation can be established and only to descend by 500ft or 1000ft. Also different States have different Contingency procedures, and my brain is not capable of remembering them, and when to apply them.
And the speed, because the engine will try to restart automatically, so needs to be at 300kts to do that.

I agree with the logic of option 1, but the FCOM does say 300/M.78. So, who is right, what is wrong and does it really matter in the actual event?
Generally speaking when these kind questions arise, try to find what Your company policy is, ie. if You have a tailored FCTM or some kind of document where these kind of legittimate doubts are clarified. Don't rely on what training captain A or B say, unless they show You what on paper (or on screen) supports their statement, which is rule N1 for a training captain anyway, so unfortunately it looks like both of them haven't done their job properly I am afraid. Regarding the strategies, they are "tools" that You will use when and how it is deemed necessary. In my company we fly 90% of our narrow body Airbus network in EU airspace, therefore busy & congested. Our tailored FCTM requires us to always start a hypothetical engine failure in cruise with an obstacle strategy to minimise altitude loss while getting things sorted out with ATC and/or terrain and then revert to standard strategy if possible.
Next time You fly with a trainer check what the official word of your operator is, basically what the guys behind the desks (that would eventually interview you after an event) would like you to do. In case there is no fixed rule but it depends on a casa by case scenario then use sound judgement as you did in Your first explanation.
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Old 11th Jul 2019, 18:13
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Originally Posted by pilot-737 View Post
I think the name of each strategy is quite clear.
1 Obstacle strategy (to be used in case of engine failure, if the EO crz level is affected by en route obstacles).
2 ETOPS strategy (to be used in order to achieve ETOS certification).
3 Standard strategy (to be used whenever the 2 previous strategies are not applicable).

Standard strategy ensures the a/c will remain within the windmilling relight envelope and supports the automatic relight attempt.
(my underline)

Just like you describe, the STD strategy is in fact a recipe for an immediate descent with a relight attempt. The naming is not optimal, that's a Relight strategy. What you'd end up doing for a simple (ehm) flameout as "standard" actually might be
- maximize level flight
- talk to ATC, no steep descent needed
- about .76 / 275 speed
- consider the relight NOT.
Unless there are reasons to adopt something else.

Funny fact, if you really had high terrain beneath, is that not just about the only case, where a relight shall be attempted at all cost?

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Old 11th Jul 2019, 18:59
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Personally use the Obstacle strategy - have you tried the relight strategy in the sim and noted the Altitude loss?
Also Apu can be used to start if required at 20 000ft.
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Old 11th Jul 2019, 20:56
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Originally Posted by Greek God View Post
Personally use the Obstacle strategy - have you tried the relight strategy in the sim and noted the Altitude loss?
Also Apu can be used to start if required at 20 000ft.
Yes i had. I was able to recover the engine well above FL 300..... but why should you maintain your cruising level at all cost in case of engine failure if you are not obstacle limited? After all you are in a "pan-pan" situation .... is there any reason be hesitant to leave the airway and to start a descent in case of engine failure ? I suppose the TCAS below function is used to enhance your SA for this kind of situations......

In case of engine failure during T/O, the ATC is expecting you to follow the SID in order to be clear of traffic as well. Would you first ask for a
clearence in order to join the EO escape route? Will you just fly the escape route and then declare the situation/ inform the atc about your intentions?

During normal operation, Fly-navigate-communicate is the right way..... during abnormal the communicate part becomes the first priority.....????

I'm always talking about the 320 so an engine failure means 50% loss of thrust.... and if you are 1000 ft above opt altitude and you fly an Econ CI..... just try in the sim how much time is available to coordinate your descent before reaching GD speed.....

Last edited by pilot-737; 12th Jul 2019 at 08:35.
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Old 12th Jul 2019, 03:05
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I politely suggest to keep the discussion on the use TCAS position display for traffic avoidance for later as well.

The idea is to maximize level flight BEFORE (until the point when) a heading and descent clearance is calmly negotiated with ATC, one that fits the best for both sides of the radio. Definitely not at any cost.

If you can work the steps of the STD (relight) strategy in a measured pace, talking first, there is no need for something else, really. But blindly applied, forcing A-N-C thus descending first and coordinating later is not a way to do it.

It is a STRATEGY. Not a SOP, not a technique, just a course of action. For the 3 limiting cases Airbus has put it on paper, to plot the area. We do not necessarily operate at its edges.

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Old 12th Jul 2019, 03:46
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Originally Posted by Good Business Sense View Post

I should remember the Airbus info in better detail after three engine failures on it (and another 9 on other stuff) but getting old !

Best
With that sort of experience, thats good enough for me. Green Dot it is.
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Old 12th Jul 2019, 04:44
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Sorry to digress a little bit - has anyone used the Flysmart inflight application to calculate OEI ceiling? On my app, it doesn’t tally with the paper QRH OEI ceilings. The app always calculate an altitude about 5000ft above compared to the paper QRH. Why the huge discrepancy?
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Old 12th Jul 2019, 08:55
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Originally Posted by FlightDetent View Post

It is a STRATEGY. Not a SOP, not a technique, just a course of action. For the 3 limiting cases Airbus has put it on paper, to plot the area. We do not necessarily operate at its edges.
According to Airbus FCTM :

There are three strategies available for dealing with an engine failure in the cruise:
. The standard strategy
. The obstacle strategy
. The fixed speed strategy


Unless a specific procedure has been established before dispatch (considering ETOPS or mountainous areas), the standard strategy is used.


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Old 12th Jul 2019, 09:50
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Funny fact, if you really had high terrain beneath, is that not just about the only case, where a relight shall be attempted at all cost?
Why this obsession with relight. Auto relight has failed now the next relight attempt will be in relight zone. CFM envelope starts at 250. There is an Airbus presentation on Dual Engine flame out which clearly describes the area above relight envelope as No relight zone. So descent can wait till ATC is informedd turn to leave the airway is initiated. May be do not have to reduce to GD.
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Old 12th Jul 2019, 12:36
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Originally Posted by vilas View Post
Why this obsession with relight. Auto relight has failed now the next relight attempt will be in relight zone. CFM envelope starts at 250. There is an Airbus presentation on Dual Engine flame out which clearly describes the area above relight envelope as No relight zone. So descent can wait till ATC is informedd turn to leave the airway is initiated. May be do not have to reduce to GD.
Agree - Aviate, Navigate, Communicate, Relight (Maybe)

Sometimes the universe doesn't acknowledge airbus engine out strategies . :-) ...... and, in my experience, it rarely happens in the cruise
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Old 12th Jul 2019, 14:31
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Originally Posted by pilot-737 View Post


According to Airbus FCTM :

There are three strategies available for dealing with an engine failure in the cruise:
. The standard strategy
. The obstacle strategy
. The fixed speed strategy


Unless a specific procedure has been established before dispatch (considering ETOPS or mountainous areas), the standard strategy is used.



I totally agree with pilot-737. Why is it we always come across Mavericks who like to force their own inputs and interpretations on others. If there is no other safety reason or factor involved, just do what the books tell you and navigate to wherever and however you need to to survive.
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Old 12th Jul 2019, 14:42
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Originally Posted by pilot-737 View Post


According to Airbus FCTM :

There are three strategies available for dealing with an engine failure in the cruise:
. The standard strategy
. The obstacle strategy
. The fixed speed strategy


Unless a specific procedure has been established before dispatch (considering ETOPS or mountainous areas), the standard strategy is used.


It is pretty much operator's specific.
Quote from my operator's tailored FCTM (EASA land major) :

When an engine failure occurs during cruise, three possible strategies apply:

‐ The standard strategy

‐ The obstacle strategy

‐ The fixed speed strategy.

Unless a specific procedure has been established before dispatch (considering ETOPS or
mountainous areas), the Obstacle strategy is used.

Airbus gives You tools, the way You decide to use them is up to you as an operator. When you tailor any documents it is important to have a no objection/green light from the manufacturer so that you can adapt the procedures to your specific needs.

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Old 12th Jul 2019, 14:50
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Originally Posted by pilot-737 View Post


Yes i had. I was able to recover the engine well above FL 300..... but why should you maintain your cruising level at all cost in case of engine failure if you are not obstacle limited? After all you are in a "pan-pan" situation .... is there any reason be hesitant to leave the airway and to start a descent in case of engine failure ? I suppose the TCAS below function is used to enhance your SA for this kind of situations......



The TCAS is a valuable tool but cannot be used to provide Your own separation with other traffic. In busy airspace you need some kind of coordination with ATC.

Originally Posted by pilot-737 View Post
In case of engine failure during T/O, the ATC is expecting you to follow the SID in order to be clear of traffic as well. Would you first ask for a
clearence in order to join the EO escape route? Will you just fly the escape route and then declare the situation/ inform the atc about your intentions?
You are expected (if possible) to declare a mayday and inform ATC of your flight path deviation before reaching the diversion point between the SID and the EO procedure. Fly, navigate, communicate, as You say.
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