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ENG Failure Strategy

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ENG Failure Strategy

Old 12th Jul 2019, 19:28
  #21 (permalink)  
 
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Originally Posted by sonicbum View Post
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.



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.
In case of Emergency/ abnormal don't you think the use of any available information is allowed ? What is the reason to select TCAS "below" after the TOC?

"If possible" also means "whenever possible".

I think the main issue is due to the fact that an engine failure is considered a LAND ASAP amber situation (pan-pan). But keep in mind that if you are performance limited (single engine) with a slow speed, you are also vulnerable to the effects of adverse wx (Turbulence, Icing etc).
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Old 12th Jul 2019, 19:47
  #22 (permalink)  
 
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Originally Posted by pilot-737 View Post


In case of Emergency/ abnormal don't you think the use of any available information is allowed ? What is the reason to select TCAS "below" after the TOC?
The TCAS information is not good enough to provide your own separation with other aircrafts and, in addition, you are not trained for it nor it is its purpose. It definitely gives you the big picture of surrounding traffic though, and you can hence estimate where you would cause less damage should you start descending like a bleeding stone... but to be accurate you need the picture of atc radar or to be in a fighter jet.

Last edited by sonicbum; 12th Jul 2019 at 20:00.
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Old 12th Jul 2019, 20:59
  #23 (permalink)  
 
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Originally Posted by sonicbum View Post

The TCAS information is not good enough to provide your own separation with other aircrafts
It is good enough to let you know if an aircraft is on the same airway or off to one side or the other.

Originally Posted by pilot-737 View Post
I think the main issue is due to the fact that an engine failure is considered a LAND ASAP amber situation (pan-pan).

i would suggest declaring a MAYDAY for an engine failure.

​​​​​​​The way I see it PAN PAN is an urgency call, and I would think that ATC still remains in control but gives you preferential treatment. Whenever you need to start doing your own navigating, and letting ATC know after the fact then you should be declaring a MAYDAY.
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Old 12th Jul 2019, 23:00
  #24 (permalink)  


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My reasoning for the obstacle strategy is that it seems to be much calmer structured and ultimately safer.
Cruise at 38/390 at normal Operating weights and CI is around 230-245 kts IAS. To accelerate to 300kts requires a significant nose down and high descent rate - you may achieve relight parameters by 30000ft but at a loss of 8-9000ft in busy airspace? As has been mentioned an engine that has failed and then failed to autorelight has issues. MCT, drift to GD then A/T off and open descent FCU to seng opt will, in my opinion give more capacity to ANC! Sort the eng failure according to SOPs / ops requirements and if necessary use the APU. Hardly think that's being a Maverick.
Likewise Airbus recommends “When clear of obstacles, revert to Standard Strategy.” Any idea on the height sacrificed to get from GD to 300kts !! Why no mention of assisted relight with APU or if u/s other eng?
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Old 12th Jul 2019, 23:41
  #25 (permalink)  
 
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Originally Posted by Greek God View Post
Cruise at 38/390 at normal Operating weights and CI is around 230-245 kts IAS. To accelerate to 300kts requires a significant nose down and high descent rate - you may achieve relight parameters by 30000ft but at a loss of 8-9000ft in busy airspace? As has been mentioned an engine that has failed and then failed to autorelight has issues. MCT, drift to GD then A/T off and open descent FCU to seng opt will, in my opinion give more capacity to ANC! Sort the eng failure according to SOPs / ops requirements and if necessary use the APU. Hardly think that's being a Maverick.
Likewise Airbus recommends “When clear of obstacles, revert to Standard Strategy.” Any idea on the height sacrificed to get from GD to 300kts !! Why no mention of assisted relight with APU or if u/s other eng?
You are not able to accelerate to 300kts at FL 380/390 because you are MMO limited.Just keep .78 until you meet the equivalent 300 Kts indicated.Combined with MCT thrust on one engine, what is the reason to "Dive"?
The same when clear of obstacles, just descent 2000ft below your Green dot ceiling and let the MCT do the job.
I think some pilots confuse the Emergency Descent with the STD strategy drift down procedure. Although open descent mode is used in both cases, you are not in idle thrust.
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Old 13th Jul 2019, 00:04
  #26 (permalink)  
 
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Originally Posted by Airmann View Post
It is good enough to let you know if an aircraft is on the same airway or off to one side or the other.
i would suggest declaring a MAYDAY for an engine failure.

​​​​The way I see it PAN PAN is an urgency call, and I would think that ATC still remains in control but gives you preferential treatment. Whenever you need to start doing your own navigating, and letting ATC know after the fact then you should be declaring a MAYDAY.
5.3.3.1.1 In addition to being preceded by the radiotelephony urgency signal PAN PAN (see 5.3.1.2), preferably spoken three times and each word of the group pronounced as the French word “panne”, the urgency message to be sent by an aircraft reporting an urgency condition shall:
a)​be on the air-ground frequency in use at the time;
b)​consist of as many as required of the following elements spoken distinctly and, if possible, in the following order:
1)​the name of the station addressed;
2)​the identification of the aircraft;
3)​the nature of the urgency condition;
4)​the intention of the person in command;
5)​present position, level (i.e. flight level, altitude, etc., as appropriate) and heading;
6)​any other useful information.

With a Pan call, according to ICAO, you just state your intentions.


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Old 13th Jul 2019, 04:24
  #27 (permalink)  
 
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Crikey, whatever happened to airmanship and managing the aircraft depending on what your situation is?

The FCTM or indeed any other manual is not a recipe book - have this failure do that - rather it is a document that outlines ways you can resolve common problems (or in reality not so common problems).

as other posters have pointed out modern jet engines don’t just throw in the towel and fail because they have nothing better to do. They either run out of fuel or have some serious problem which prevents the bits that go round in circles from going round in circles, so the debate about preventing auto relights etc is possibly valid BUT in my mind I am not sure I want an engine which has taken it upon itself to stop to keep trying to restart itself.

It may have stopped due to heavy rain or icing, which is fair enough, but other than that it would be a significant problem which makes it stop running.

My view on the world is perhaps too “maverick” as some call it, but I will assess the problem and hopefully react appropriately. I won’t predetermine how I will deal with each situation because the context is unknown.

I worry about pre determined actions to unknown circumstances because I reckon there are too many variables.

Perhaps that makes me unprofessional, I don’t know, I prefer to think of it as adaptable and professional.

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Old 13th Jul 2019, 08:02
  #28 (permalink)  
 
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Originally Posted by Snakecharma View Post
Crikey, whatever happened to airmanship and managing the aircraft depending on what your situation is?

The FCTM or indeed any other manual is not a recipe book - have this failure do that - rather it is a document that outlines ways you can resolve common problems (or in reality not so common problems).

as other posters have pointed out modern jet engines don’t just throw in the towel and fail because they have nothing better to do. They either run out of fuel or have some serious problem which prevents the bits that go round in circles from going round in circles, so the debate about preventing auto relights etc is possibly valid BUT in my mind I am not sure I want an engine which has taken it upon itself to stop to keep trying to restart itself.

It may have stopped due to heavy rain or icing, which is fair enough, but other than that it would be a significant problem which makes it stop running.

My view on the world is perhaps too “maverick” as some call it, but I will assess the problem and hopefully react appropriately. I won’t predetermine how I will deal with each situation because the context is unknown.

I worry about pre determined actions to unknown circumstances because I reckon there are too many variables.

Perhaps that makes me unprofessional, I don’t know, I prefer to think of it as adaptable and professional.

Greek God, Snakecharma - exactly

Experienced an engine failure in the climb through 37,000 to 41,000 - aircraft (A330) ran out of energy quickly but to complicate matters greatly due to a major bleed problem we also had a depress ....... which "strategy" on this ETOPS sector ? Which part of the manual covers that engine out combo ?
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Old 13th Jul 2019, 09:19
  #29 (permalink)  
 
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Originally Posted by Good Business Sense View Post
Greek God, Snakecharma - exactly

Experienced an engine failure in the climb through 37,000 to 41,000 - aircraft (A330) ran out of energy quickly but to complicate matters greatly due to a major bleed problem we also had a depress ....... which "strategy" on this ETOPS sector ? Which part of the manual covers that engine out combo ?
Obviously you can't climb. If you are closer to GD you got to descend, turn off, select .78 or whatever suggested.
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Old 13th Jul 2019, 11:27
  #30 (permalink)  
 
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Originally Posted by sonicbum View Post
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.
Tailored manuals are sometimes reflecting the personal opinion of the training / flight ops management of the company(sometimes affected by the previous type / experience of the managers). For this reason is always interesting to refer to the original documents.
Is there any sense to say :

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

Based on this, they should remove the STD strategy from your manuals as you are not allowed to use it anyway.
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Old 13th Jul 2019, 11:38
  #31 (permalink)  
 
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Originally Posted by Good Business Sense View Post
Greek God, Snakecharma - exactly

Experienced an engine failure in the climb through 37,000 to 41,000 - aircraft (A330) ran out of energy quickly but to complicate matters greatly due to a major bleed problem we also had a depress ....... which "strategy" on this ETOPS sector ? Which part of the manual covers that engine out combo ?
Engine failure during climb is a very interesting scenario. In this case if you just set the good engine to MCT, the autoflight will adjust the pitch to keep the speed resulting to a descent. Are you going to try to maintain the present altitude in order to request an ATC HDG? Just try this scenario in the sim while climbing to fl 380.
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Old 13th Jul 2019, 14:37
  #32 (permalink)  
 
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Originally Posted by pilot-737 View Post


Tailored manuals are sometimes reflecting the personal opinion of the training / flight ops management of the company(sometimes affected by the previous type / experience of the managers). For this reason is always interesting to refer to the original documents.
Is there any sense to say :

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

Based on this, they should remove the STD strategy from your manuals as you are not allowed to use it anyway.
Nope, that's not the case. In this specific context we are expected to start a hypothetical engine failure in cruise with the obstacle strategy and, when things are sorted out, revert to standard strategy.
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Old 13th Jul 2019, 16:03
  #33 (permalink)  
 
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Originally Posted by IBE8720 View Post

Recently Training Captain was suggeting Green Dot should be the intial speed selection in all circumstances of ENG Failure in CRZ.
...
I agree with the logic of option 1...
That last sentence says enough. It gives you enough time to inform ATC and come up with an initial plan.
Turning left of right is a contingency procedure for oceanic or remote airspace in case of being unable to get a revised clearance. Turning left or right in busy airspace is not necessary the best option. Going straight ahead might be safer due to traffic. Minimising your altitude loss is common sense to me, especially in EU RVSM. You can always revert to the standard strategy later.
If it happens, you decide what the best option for that situation is. There is no perfect strategy that covers all situations.
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Old 13th Jul 2019, 21:05
  #34 (permalink)  
 
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Originally Posted by pilot-737 View Post


Engine failure during climb is a very interesting scenario. In this case if you just set the good engine to MCT, the autoflight will adjust the pitch to keep the speed resulting to a descent. Are you going to try to maintain the present altitude in order to request an ATC HDG? Just try this scenario in the sim while climbing to fl 380.
Sorry guys, didn't mean to confuse - wasn't asking a question - it actually happened - was pointing out that airbus et all don't write strategies (def. Plan of action) for everything. They can't dream them all up so you need to use you knowledge and experience and deal with them accordingly.
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Old 14th Jul 2019, 10:52
  #35 (permalink)  
 
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Originally Posted by Bus Driver Man View Post
That last sentence says enough. It gives you enough time to inform ATC and come up with an initial plan.
Turning left of right is a contingency procedure for oceanic or remote airspace in case of being unable to get a revised clearance. Turning left or right in busy airspace is not necessary the best option. Going straight ahead might be safer due to traffic. Minimising your altitude loss is common sense to me, especially in EU RVSM. You can always revert to the standard strategy later.
If it happens, you decide what the best option for that situation is. There is no perfect strategy that covers all situations.

Agreed. If I ever lose an engine in busy EU airspace I will initially adopt the obstacle strategy. I consider other bits of high speed aluminium as obstacles. I can always change the strategy once things are under control and ATC are pointing me somewhere safe.

Unless you are a long way from a runway, surely the safest course of action is to land at the nearest suitable. Phone Ops and tell them their aircraft is broken. Send engineers to fix it.

Relight and continue? No thanks.

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Old 14th Jul 2019, 13:22
  #36 (permalink)  
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I have been through my manuals in fine detail. The answer is in the FCOM and on ECAM, and common sense and airmanship merely confirm the actions.
  1. Jeppessen states the preferred Navigation procedure is to stay ON planned route. The turn off is a contingency in the event no alternate clearance can be obtained.
  2. For CFM engines, A320 FCOM says, “if conditions permit, do not restart the engine.” Every simualtor check I have been required ot call engineering before re-lighting/starting an engine after any sort of malfunction. So why would it be any different in real life?
  3. If you are airborne, the engine will attempt an automatic relight regardless of the ENG Mode SEL rotary switch position. So the “if no relight after 30sec….” is from the time the failure was detected by FADEC, not when the rotary switch is selected to ignition. The selection of the rotary switch to ignition only CONFIRMS that continuous ignition is be applied.
  4. The ECAM calls for ENG MST - OFF. This action will stop any automatic attempted relight. Therefore, once you reach this point in ECAM, there is no reason to be flying at 300kts/M.78. My airline QRH calls for FL250 to be in the ENG Relight Envelope.
  5. As an exercise yesterday I timed myself running through the engine failure in cruise procedure. Tom Hanks doesn’t have the most successful aviation career, he did correctly say after he completed his famous controlled landing on water. “You can accomplish anything if you have enough time.”

I gave myself 7sec (Tome Hanks was given 30sec for reaction time by the ATSB at the inquiry) to detect the engine failure.

Another 8sec to complete the ENG Failure CRZ actions (15sec total).

At least 10sec to get a call into ATC (25sec).

So at 25sec we are starting ECAM actions. In 5sec time I will have taken over 30sec, ECAM is going to tell me to turn the ENG MST - OFF. This action turns the engine off and will stop any automatic attempted relight, regardless of my speed, engine windmilling etc. So why am I still descending at M.78/300kts with my engine turned off?

Green Dot, MCT and V/S -500fpm is 2min before I will be conflicting with other traffic (1,000ft separation), by now ATC should have them getting out of my way.

As others have stated Airbus can’t write the manuals for every conceivable scenario. FCOM is more of a 1 size fits all manual to cover them legally in court.

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Old 14th Jul 2019, 14:54
  #37 (permalink)  
 
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I thought it was Tom Hanks who was actually playing Sully, not the other way around.
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Old 14th Jul 2019, 16:59
  #38 (permalink)  
 
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IBE8720
Moment engine fail appears on ECAM the FADEC switches on both igniters and and tries auto relight varies fuel flow etc. for 30 seconds. If it fails then ignition is switched off, no more auto relight. Only then ECAM appears not before. So when ECAM appears 30sec are over.
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Old 14th Jul 2019, 20:02
  #39 (permalink)  
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even more reason to adopt Obstacle Strategy.
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Old 16th Jul 2019, 16:32
  #40 (permalink)  

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@vilas: just to verify I read you correctly ENG 1: FAIL shows straight away but the blue action lines only appear after the 30 sec?

-------------

@IBE8720 My take on the schism between the general agreement here (slow, obstacle) and the original wording: go STD unless pre-determined otherwise.

The strategies come from the PERFORMANCE section of the manual. Such must be published to do the math necessary before dispatch. The STRATEGIES themselves are not a prescribed ABN PROC drill. We have some explanations available from the FCTM, but then again FCTM does not come near the diamond polished standards and clear cut wordings of the FCOM.

a) The STD strategy at M 0.80/300 kt overlaps with the IAS range for a possible restart. Though relight is officially advised against, but that is not mutually exclusive. BTW, the Stabilized Windmill Relight Envelopes are
IAE: only below FL300, speed above 260 kt
CFM: only below FL250, speed above 275 kt down to FL110 (simplified)
PW: only below FL280, speed above 260 kt



b) What does the FCOM (nee FCTM) actually say, even if in the PERF section? Here:
"Depending on the prevailing operational constraints, the most appropriate diversion strategy shall be selected, out of the following options:"
"based on the evaluation of the actual situation, the pilot in command has the authority to deviate from this planned one engine inoperative speed."

-------------

That's it. The OEI PERFORMANCE STRATEGIES are not ABN DRILL procedures. Designed to provide calculated profiles required before dispatch which must be realistic and flyable. Hence the instruction to use them in the FCTM.

Before typing this post I believed the STD strategy was based on an engine restart speed profile, which now think is definitely not the case. This is actually version 3 of what I write. The second one which suggested 300 kt is linked to the OEI CRZ speed and the 60 minute-distance rule is now binned too.

What I'd do with the best intentions is:
1) both TL to MCT, A/THR off. Advise PF to declare an emergency and get us a descent clearance with a heading as appropriate, PRONTO. Seat belt on. Immediate DES if unable to stay above GD.
2) Fly as cleared by ATC (or regional procedure) with selected present Mach at that moment.
3) ECAM actions, no relight intended. Do not push out the fire sw unless damage is suspected.
4) Review the diversion plan and start executing it.
5) Pick 280 kt +/- 10 after the IAS transition, depending on the weight, HWC/TWC and fuselage length.

While not one of the strategies exactly, I believe that satisfies the present FCOM requirements as laid out in the PERFO section, in the absence of specific ABN PROC and overruling operational constraints.

In the case of ETOPS ops, would fly 0,78 or 300 knots, not the 320 or 350.
In the case of limiting terrain, would fly the GD profile AND attempt a relight.


There is still one rather large piece of doubt if discarding the 0.78/300 is that easy, but I'd need to sleep over it. Along what @pilot-737 says.

Last edited by FlightDetent; 16th Jul 2019 at 16:51.
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