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Go Around procedure for One Engine Out

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Go Around procedure for One Engine Out

Old 13th Aug 2019, 08:35
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Go Around procedure for One Engine Out

I understand that some airport under special conditions such as high terrain within the vicinity of it, has their own special engine failure procedure, so as to keep the aircraft within a safe margin from the obstacles around it even with the aircraft reduced performance.

Now the question is, when we execute a go around, do we follow the original missed approach procedure or are we supposed to follow the special engine failure procedure?

Some of my colleague says to follow the missed approach procedure while others to follow the special engine failure procedure...

Can anyone enlighten me on this?

Last edited by Ondraayyy; 13th Aug 2019 at 12:40.
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Old 13th Aug 2019, 08:48
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How many engines are operating? That should give you the answer you are looking for. The engine out go around procedure is often company specific provided by your own performance engineers.
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Old 13th Aug 2019, 10:42
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Not really as simple as that, I'm afraid.

(a) the usual takeoff should only be used for takeoff OEI if your performance folk have done the sums for OEI, as they should have, determined and published words to the effect that the departure is acceptable for OEI.

(b) if the normal takeoff doesn't work for OEI, then there should be published an acceptable escape procedure for takeoff.

(c) when it comes to the miss, neither of the above necessarily fit the profile for the miss (or vice versa, if you prefer). Reasons will relate to speeds, turns in relation to specific terrain (speed/radius of turn) configuration and changes, and position in respect of the runway at the commencement of the miss, tracking and tracking accuracy and so on. That is to say, unless the performance folks have done some sensible sums, and published a way out, you can't necessarily presume that this or that will be acceptable and work.

(d) do all operators look after this stuff ? Not for me to opine - however, for my customers the answer is yes. Same for Old Smokey, Mutt and other ops engineers who have an understanding of frights from the cockpit ....
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Old 13th Aug 2019, 11:08
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My company publishes separate engine failure procedures for takeoff and go around. A320
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Old 13th Aug 2019, 11:36
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Depends on type of aircraft, operation and company. Most if not all companies have an EOSID/EOMA procedure for each runway if the published SID/M-APP procedure doesn't provide enough terrain clearance
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Old 13th Aug 2019, 12:19
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Well. this is a first...

Originally Posted by Ondraayyy View Post
I understand that some airport under special conditions such as high terrain within the vicinity of it, has their own special engine failure procedure, so as to keep the aircraft within a safe margin from the obstacles around it even with the aircraft reduced performance.

Now the question is, when we execute a go around, do we follow the original missed approach procedure or are we supposed to follow the special engine failure procedure?

Some of my instructors says to follow the missed approach procedure while others to follow the special engine failure procedure...

Can anyone enlighten me on this?
There is debate amongst your instructors about wether to apply Special Engine Failure Proceedure OEI??
I've seen this written on PPRuNe a handful of times before, but never thought I'd have to say it...
-Please tell me the name of your Airline so everyone can avoid flying it.

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Old 13th Aug 2019, 12:33
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Standard Missed Approach procedure designed i.a.w ICAO Doc 8168 requires you to make 2,5% gradient. Warning: there is no allowance for a level acceleration segment, just 2,5% all the way until the MisApch altitude.

For OEI, it is the operators' responsibility to do the math (tkof, enrt and ldg) - at all times. The performance for MisApch from the airworthiness requirements requires is 2,4% for modern twins (Perf class A), and so 2,5 is doable or you must restrict the LW accordingly anyway. So the AOC holder should run the figures for 2,5 (or as charted) before dispatch and later following the prescribed MisApch is enough. Well, until you run out of MAX TOGA time on the remaining engine (maybe keep this element for a later debate).

Cannot speak for quads, trimotors or other performance classes.

A pretty decent layout is (in general)
- AEO at minima or above -> follow the MAPr
- AEO below minima -> avoid close-in obstacles visually and rejoin the MAPr
- OEI at minima or above AND the charted gradient (2,5% unless stated higher) is checked OK -> follow the MAPr
- OEI below minima OR unable to make the published gradient -> follow a specific procedure (most likely the OEI instrument tkof procedure for that runway)

If the above is not sufficient, then by definition we are talking about an airport requiring special performance considerations. The assessment of which is a legal responsibility of the AOC holder, who must then provide the necessary procedure / calculated solution AND training how to apply it to the crews.

That's how I heard it.

Last edited by FlightDetent; 13th Aug 2019 at 14:53. Reason: grammar, at least some.
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Old 13th Aug 2019, 12:37
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Simply stating special engine out procedure is vague. Is it for takeoff or missed approach or both? The takeoff procedure or SID maybe turning you to the right the MA may be turning to the left. Assuming both are in the same direction the vertical profile starts at different points. MA may may make it takeoff may not meet it.
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Old 13th Aug 2019, 12:38
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Originally Posted by neilki View Post
There is debate amongst your instructors about wether to apply Special Engine Failure Proceedure OEI??
I've seen this written on PPRuNe a handful of times before, but never thought I'd have to say it...
-Please tell me the name of your Airline so everyone can avoid flying it.
I asked for an answer, not an opinion. Thanks

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Old 13th Aug 2019, 12:39
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Originally Posted by FlightDetent View Post
Standard Missed Approach procedure per ICAO Doc 8168 needs you to make 2,5% gradient. Warning: level acceleration segment is no longer a design requirement for those, thus 2,5 all the way up to Missed Approach final altitude may be needed.

pretty decent layout is (in general)
- AEO at minima or above -> follow the MAPr
- AEO below minima -> avoid the imminent close-in obstacles visually and rejoin the the MAPr and
- OEI at minima or above AND the charted gradient (2,5% unless stated higher) checked OK -> follow the MAPr
- OEI below minima OR unable to make the published gradient -> follow a specific procedure (most likely the OEI instrument tkof procedure for that runway)


Thank you for the enlightenment This answer my question...
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Old 13th Aug 2019, 12:59
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A) its not an opinion. It's reflective of the likelihood of CFIT.
B) The answer is -you fly the procedure for each scenario as defined by your Aircraft specific Company provided performance solution..
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Old 13th Aug 2019, 13:02
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On A320 and I believe on any modern airliners you are never limited in climb gradient with all engines operating.
We do our performance calculation using Flysmart on Ipad and we have the engine out go around gradient displayed for awareness so we know if we can comply with the required climb gradient or if we must follow the EOSID.
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Old 13th Aug 2019, 13:06
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Originally Posted by pineteam View Post
On A320 and I believe on any modern airliners you are never limited in climb gradient with all engines operating.
We do our performance calculation using Flysmart on Ipad and we have the engine out go around gradient displayed for awareness so we know if we can comply with the required climb gradient or if we must follow the EOSID.
Terrain Performance or Departure Performance?
In the US, the A320 is certainly limited in some Altitude Constraints on SIDs. In fact, ORD just added a lateral half mile to its' DME/Alt requirements, and a heavy 321 on a hot day out of LAS will struggle above Green Dot....
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Old 13th Aug 2019, 13:16
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Originally Posted by Ondraayyy View Post
I understand that some airport under special conditions such as high terrain within the vicinity of it, has their own special engine failure procedure, so as to keep the aircraft within a safe margin from the obstacles around it even with the aircraft reduced performance.

Now the question is, when we execute a go around, do we follow the original missed approach procedure or are we supposed to follow the special engine failure procedure?

Some of my colleague says to follow the missed approach procedure while others to follow the special engine failure procedure...

Can anyone enlighten me on this?
Hi,

when You do your calculations for dispatch landing performance You will realize that in those kind of scenarios the approach climb gradient will limit your MLW, therefore 2 options : 1) Your ops establish an alternative missed approach if feasible performance wise or 2) you decrease your LW to comply with the missed approach gradient.
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Old 13th Aug 2019, 13:17
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Originally Posted by pineteam View Post
On A320 and I believe on any modern airliners you are never limited in climb gradient with all engines operating.
We do our performance calculation using Flysmart on Ipad and we have the engine out go around gradient displayed for awareness so we know if we can comply with the required climb gradient or if we must follow the EOSID.
Missed approach climb is always considered single engine and can (and will) be a limiting factor.
The landing climb gradient is considered all engines and is generally never limiting.
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Old 13th Aug 2019, 13:21
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Originally Posted by neilki View Post
Terrain Performance or Departure Performance?
In the US, the A320 is certainly limited in some Altitude Constraints on SIDs. In fact, ORD just added a lateral half mile to its' DME/Alt requirements, and a heavy 321 on a hot day out of LAS will struggle above Green Dot....
Yes terrain performance. = ) Yeah Heavy A321 250kt won’t comply with some altitude constraints during departure.
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Old 13th Aug 2019, 14:23
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Originally Posted by neilki View Post
A) its not an opinion. It's reflective of the likelihood of CFIT.
B) The answer is -you fly the procedure for each scenario as defined by your Aircraft specific Company provided performance solution.
If you stood by your word, and would only fly airlines who provide their pilots with a monkey read - monkey do scenarios for the discussed case, I reckon you would not travel very far.

A heavy A321 is when after the DER turn you are climbing AEO with 11,5 deg pitch on flaps 3 at 300 fpm, and start questioning your memory banks what exactly was the engine out attitude after takeoff.
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Old 13th Aug 2019, 14:41
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Originally Posted by Ondraayyy View Post
Thank you for the enlightenment This answer my question...
If you do follow the MAPr on -1 engine, be prepared to answer the question when will you accelerate and how to observe the TOGA engine limits. In this regard people who advocate a dedicated OEI procedure at all times are standing on the cleaned side of the street.
-
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Old 13th Aug 2019, 15:26
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Originally Posted by sonicbum View Post


Hi,

when You do your calculations for dispatch landing performance You will realize that in those kind of scenarios the approach climb gradient will limit your MLW, therefore 2 options : 1) Your ops establish an alternative missed approach if feasible performance wise or 2) you decrease your LW to comply with the missed approach gradient.
I get it now, the key lies within the climb gradient... Thank you!
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Old 13th Aug 2019, 21:11
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Originally Posted by pineteam View Post
We do our performance calculation using Flysmart on Ipad and we have the engine out go around gradient displayed for awareness so we know if we can comply with the required climb gradient or if we must follow the EOSID.
Without checking, what is the default climb gradient shown in the Flysmart landing module (in flight)?
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