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TOGA Tap
18th Sep 2018, 13:41
A question for sim trainers / examiners ( and applicable in real life too ):

Suppose we are taking of at maximum design take off weight.
On take off there is an engine failure with damage and smoke in cabin so we have first to follow the engine the EOSID and land over-weight almost immediately after that - at least there is no time to reduce weight.

On the short final the proverbial aircraft on the runway appears and the ATC issues the Go Around commmand.

So now aircraft is close to MAX To and single engine in a Go Around.

What we have to follow the Missed Approach procedure or the EOSID and what are the performance considerations then?

agg_karan
18th Sep 2018, 14:44
Anytime our company came out with a EOSID, we were also told whether to follow that EOSID for a MAP as well for that runway. In HKG circular for us says follow EO routing if MAP with singLe engine.

i think your operator as well should tel you to resolve this ambiguity. What criteria they determine to do or NOT to do is upto them.

underfire
18th Sep 2018, 15:43
You have an EOSID, but not an EO Missed? Aside from that, When you GA don't you follow the missed approach?

eckhard
18th Sep 2018, 19:35
The two profiles start under different circumstances.

1. EFTO: approaching the end of the runway, ground level, gear down, fixed flap setting until accel ht, probably reduced thrust.

2. EO GA: 2/3nm from threshold (potentially nearly 3nm before the EFTO point), 200ft agl, gear about to retract, flaps retracting to the GA setting and full thrust available.

So, while following the EOSID might be wise, it depends on the circumstances and may not be necessary.

Goldenrivett
18th Sep 2018, 19:54
All Jeppesen missed approach profiles quote a minimum climb gradient up to MSA, first stop Alt or Acceleration Altitude. If you canít make the published gradient then youíll need another plan.

underfire
18th Sep 2018, 22:32
So, while following the EOSID might be wise, it depends on the circumstances and may not be necessary.

So if there is an EO SID, you ignore the Missed Approach procedure?

J74
19th Sep 2018, 00:41
As somebody tried to point out the scenario, basically if you take off and you have and EO, taking for example HKG, and you are at MTOW you have to follow the contingency procedure, as the normal SID gradient maybe too high in respect what you need (you have to calculate this according your actual aircraft mass and see if you still able to produce the requred climb gradient)
But if you go around, depends, at which distance and/or Height you go around, probably able to follow the go around profile...if not able due the gradient be too high for your actual condition, again, you need to follow your contingency procedure!
need to ask your Company!!

Skyjob
19th Sep 2018, 10:22
The two profiles start under different circumstances.1. EFTO: approaching the end of the runway, ground level, gear down, fixed flap setting until accel ht, probably reduced thrust.
2. EO GA: 2/3nm from threshold (potentially nearly 3nm before the EFTO point), 200ft agl, gear about to retract, flaps retracting to the GA setting and full thrust available.
eckhard is spot on, the missed approach starts at a different location, from a different height, therefore requires different performance for obstacle clearance, as obstacles are lower and further (comparable to OEI Takeoff). Using the departure OEI profile is SAFE, but is not REQUIRED to meet regulations. Your aircraft type and the associated minima for approach define published missed approach capability, hence on some charts minima are a factor of aircraft classification and climb gradient, which is based on your actual weight, ambient conditions etc, use the OPT (or equivalent) to find out what the capability of your type is.
Only ONE situation arises which is dubious, which is a missed approach below published minima in which case you cannot guarantee obstacle clearance as charted exists, then following the OEI profile would be safest option.

Mr Good Cat
19th Sep 2018, 10:39
All go-around procedures are based on attaining 2.5% gradient (in europe), or higher due obstacles/terrain etc(in which case it should be on your chart).

If you calculate your single-engine climb gradient (approach climb) at your current weight you can see if you will be able to achieve the required go-around gradient for that approach. If you can't achieve it then most airlines give you the option of flying the engine-out takeoff procedure for that runway (for reasons as described above).

Above all, if you're returning to land immediately due to some major time-critical event like an uncontained fire then going around isn't likely to be one of your available options - you can't plan for every eventuality and multiple scenarios.

maggot
19th Sep 2018, 10:48
Check the m.app gradient on the chart, check your gradient, if no good use the t.o. eo chart or similar.
your performance will be much better than at V1

exfocx
19th Sep 2018, 13:15
In past companies the story was, below the minimum follow the EOSID, above follow the IAP MA procedure and if that was not sufficient at max weight, the company would have procedures in place to cover that.

john_tullamarine
19th Sep 2018, 13:31
Suppose we are taking of at maximum design take off weight.

That is to say, the operation likely is WAT-limited

- at least there is no time to reduce weight.

Or else one follows the B727 double failure scenario .. initiate dumping with NO delay (presuming you have a dump provision). By the time the aircraft is back on final, a lot of fuel (and weight) has gone under bridge, as it were.

On the short final the proverbial aircraft on the runway appears and the ATC issues the Go Around command.

The mayday call on takeoff should have made this a miniscule probability

What we have to follow the Missed Approach procedure or the EOSID and what are the performance considerations then?

The main problems relate to the obstacle environment and tracking accuracy. For the missed approach the aircraft's varying (with reconfiguration) gradient capability may make the obstacle clearance considerations rather difficult unless the sums have been run ahead of time .. certainly not something to do on the fly. For the takeoff OEI escape, the problem is tracking to capture the escape path and ensuring that the aircraft configuration/speed/height is not less than the takeoff case when the aircraft gets to the runway head position.

we were also told whether to follow that EOSID for a MAP as well for that runway

That is the sums need to be run ahead of the game

You have an EOSID, but not an EO Missed? Aside from that, When you GA don't you follow the missed approach?

The unfortunate reality is that not all operators address the OEI miss case. Not much point following the published approach miss if it results in a highly likely CFIT due to degraded gradient capability ?

All Jeppesen missed approach profiles quote a minimum climb gradient up to MSA, first stop Alt or Acceleration Altitude. If you can’t make the published gradient then you’ll need another plan.

Fine AEO. However, the OEI miss is a dynamic procedure with changing gradients throughout associated with reconfiguration and acceleration. How do you match the two sets of data ?

So if there is an EO SID, you ignore the Missed Approach procedure?

If the published miss isn't going to work for you due to CFIT considerations, is there much in the way of alternatives ?

But if you go around, depends, at which distance and/or Height you go around, probably able to follow the go around profile

"Probably" doesn't cut the mustard, I fear.

Using the departure OEI profile is SAFE

But only IF you can find your way to the starting point - keep in mind that the splays aren't all that wide and there may be real tiger country to the sides ..

but is not REQUIRED to meet regulations

.. which may be paraphrased "don't crash". Now, the problem is just how you can go about making sure that that is the outcome.

Your aircraft type and the associated minima for approach define published missed approach capability

Tell me again, now .. was that AEO or OEI ?

Only ONE situation arises which is dubious, which is a missed approach below published minima in which case you cannot guarantee obstacle clearance

This is one rather MORE dubious situation ... all OEI escapes are problematic in the presence of terrain unless a bunch of sums has been run ahead of time with the calculated flight path overlaid on the terrain profile. Basically, you lose one and you are in a potential world of hurt UNLESS all the relevant and necessary sums have been done by competent personnel ahead of time.

All go-around procedures are based on attaining 2.5% gradient (in europe), or higher due obstacles/terrain etc(in which case it should be on your chart).

Hence things might be a tad sweaty in the case of OEI WAT limited situations if the pilot decides to wing things on the fly ?

If you calculate your single-engine climb gradient (approach climb) at your current weight

Now, were you going to account for the time/distance/gradients associated with reconfiguration and acceleration from landing to approach configurations ?

you can't plan for every eventuality and multiple scenarios.

That's in keeping with design and operating philosophies. We want to be very confident we can handle one major failure and reasonably confident that we have a workable plan for the second. Beyond that, sometimes it just doesn't pay to get out of bed in the morning ... Not that we don't always endeavour to have multiple fall back plans up our sleeves .. it's just a case that they might not always work out well.

your performance will be much better than at V1

Maybe yes .. maybe no. How about the case where the scheduled runway takeoff is for a low flap setting and you are starting the miss from landing flap ? Might be a bit messy ? You could have a significant speed delta to make up and a significant time/distance/gradient problem for reconfiguration. Throw away answers just don't cut the mustard, I'm afraid, for difficult airports and runways.

the company would have procedures in place to cover that.

Unfortunately, some operators fall down in this regard.

B737900er
19th Sep 2018, 19:50
The app gradient is based on OEI and usually the most limiting. The missed approach is based on a minimum of 2.5% if you cannot make this, then you cannot perform the approach, most cases at max landing weight this is not a problem.

To get extra performance being overweight, consider a bleeds/Packs off landing (of course if your performed any smoke removal checklist this may not be possible).

john_tullamarine
19th Sep 2018, 22:54
The app gradient is based on OEI and usually the most limiting.

Approach climb OEI gear up, landing climb AEO gear down, and different speeds. As to what limit may be critical, that will depend on the aircraft. The big problem is going to be reconfiguration and acceleration to get to the appropriate speeds

The missed approach is based on a minimum of 2.5%

As a procedures design consideration but doesn't consider what the aircraft constraints may be

if you cannot make this, then you cannot perform the approach

or you need to adjust the approach by, for example, adopting a higher minimum

most cases at max landing weight this is not a problem.

The OP's concern was for a maximum takeoff weight situation with an immediate return .. things might be a lot tighter now, don't you think ?

To get extra performance being overweight, consider a bleeds/Packs off landing

For a significantly overweight landing, that is a bit like rearranging the deck chairs on the Titanic, methinks.

Capn Bloggs
20th Sep 2018, 00:22
To get extra performance being overweight, consider a bleeds/Packs off landing

For a significantly overweight landing, that is a bit like rearranging the deck chairs on the Titanic, methinks.
Both packs off gives me another 0.9% compared to leaving one pack on. :ok:

john_tullamarine
20th Sep 2018, 10:29
Except that, for a lot of aircraft at MTOW OEI in the landing configuration at Vref or so ... 0.9 isn't a lot of immediate assistance ?

B737900er
20th Sep 2018, 11:20
What do you suggest John? Without being rude, you have picked apart everyones suggestions so far.

FlightDetent
20th Sep 2018, 11:53
I think JT points out that the suggestions are shoes which do not fit perfectly. He's not saying there's a better pair...

The fact alone, that there's no regulation requiring an all-round valid solution for the given scenario, provides a bit of insight.

If you have concurrently:
- MTOW tkof
- ENG fail
- A/C where MTOW >> MLW so that 2,5% is definitely not achievable even with Bleeds OFF and reduced approach flap
- the absolute necessity of a G/A in spite of a previous MAYDAY
- there are real obstacles below the MISAP path
- valley so complex where EO SID is not possible to intercept properly (bit of scaremongering here, right?)
- IMC
- and you did not run the figures beforehand at the dispatch phase

... the options are spelled out nicely above, and JT did a peer review of the risks with each of them. The task may as well be finished at this stage.

2pc.

john_tullamarine
20th Sep 2018, 13:37
Apologies if I appear to be on a black hat check witch hunt here. My concern is that a great many folk try to oversimplify that which is not amenable to such.

Two points of note -

(a) this stuff is not suitable for line crews to wing on the fly with simplistic notions .. better than nothing, certainly, but not satisfactory at all. If it is to have much show of working, it must be done in the back room ahead of time and preferably by the ops engineering folk with good OEM data and a sound engineering understanding of flight dynamics. Unfortunately, it's a rubbery area which many of us have had concerns about for decades .. can't see anything changing too soon, though.

(b) as FlightDetent infers .. the certification and operational rules cover us so far ... only ... if you get too far out of left field, it might just not be your day. There are no guarantees .. only probabilities. We do our best to load the dice our way but .. if we get too far out of line .. it just might not work out to our advantage.

What really concerns me is that folk don't appear to be hammering on the Flight Operations Manager's door to get good, sound, ops engineering work done on all non-trivial runways ... sure, it costs ... but try the cost of a CFIT with a full load of passengers.

underfire
20th Sep 2018, 19:56
John, Getting the information from Flight Ops is the best. Simply following the EOSID when going missed, especially as a blind statement, is fought with disaster. Look at MEL, follow the EOD SID when going missed RW 16, and you risk an encounter with the crossing traffic from Essendon. There are several missed approach procedures at airports where you have to do a right turn at the midpoint of the runway.
Go missed at the MAP, level, then follow the EOSID? It is unclear how you would blend the 2 procedures together in many places, not to mention other aircraft that departed after you.

Mr Good Cat
20th Sep 2018, 20:16
The missed approach is based on a minimum of 2.5%

As a procedures design consideration but doesn't consider what the aircraft constraints may be


Hence why most airlines recommend you follow the engine out takeoff procedure for that runway. If you can follow it on takeoff you can definitely make it on a go-around!

As I said - if you're returning that quickly, unplanned - you're already time critical and committed, and you can't plan for every eventuality such as a blocked runway in that scenario. In fact you probably wouldn't have time to discuss the engine out procedure and would be looking at landing ASAP however you can (taxiway / ditching?) if you're about to burn out of the sky...

HPSOV L
20th Sep 2018, 21:43
In short..:

If you took off from that runway you can land on it.
Go-round performance is assured by:

1) Check the Approach Climb gradient table to confirm available performance exceeds the MAP gradient (and Overweight Landing checklist if applicable).
2) If it doesn’t, OR a go-round is made from below the MDA/DA, then follow the engine out procedure ( which, in the case of a quick return you know because you just took off).
3) If there is a special published engine out MAP follow that instead.

Advise ATC of your intentions.

john_tullamarine
21st Sep 2018, 09:58
Getting the information from Flight Ops is the best

D'accord, providing that the data is sourced from appropriate folk on a basis of integrity. Centaurus tells a tale of an operator of his acquaintance where management didn't like the numbers for one runway with the obstacles included so they contracted to get data based on the runway and obstacle information they provided to the contractor ... guess what ? Only a problem if one quits on takeoff, I guess.

Simply following the EOSID when going missed, especially as a blind statement, is fought with disaster.

The major problem is getting the aircraft onto the escape path at or above the takeoff computed elevation with appropriate speed and configuration in the first instance. The flight path during reconfiguration and acceleration is the difficulty for calculation as the AFM generally doesn't give you any information. Then you have to worry about traffic, as you suggest. Nothing's easy .. hence the way to go is have a pre-computed ops engineering procedure for a critical miss.

Go missed at the MAP, level, then follow the EOSID?

You tell me. Keep in mind that for the overweight case postulated, lose one with landing flap/gear down and you are likely to keep going down for some time until you get the aircraft reconfigured and faster .. I keep belabouring this as it is not generally well understood. A read of JW's mishap in the F27 (VH-FNH) at Launceston many years ago highlights the problems .. https://www.pprune.org/pacific-general-aviation-questions/484781-ansett-f27-crash-lst-1965-a.html has some recollections. Full flap, gear down with one out and you should expect to keep going down ... getting to the configuration and speed you need takes time, distance, and height compromises ... not nice stuff in a critical terrain situation ?

If you can follow it on takeoff you can definitely make it on a go-around!

That might be a tad optimistic if you are starting behind the play overweight, full flap and gear down .. Reality is that, for many cases, the only sensible solution is to adopt a higher missed approach point to accommodate the intervening bit of activity before you get to the takeoff configuration, speed and track.

If you took off from that runway you can land on it.

Again, not always a shoe-in .. depends on takeoff and landing configurations/speeds.

1) Check the Approach Climb gradient table to confirm available performance exceeds the MAP gradient (and Overweight Landing checklist if applicable).

Now, where did you figure in the distance and height delta requirements for reconfiguration and acceleration ?

2) If it doesn’t, OR a go-round is made from below the MDA/DA, then follow the engine out procedure ( which, in the case of a quick return you know because you just took off).

Same question ..

3) If there is a special published engine out MAP follow that instead.

Ah, that's the better way to approach things.

Again, I may appear just to be a silly old pharte worrying about this and that ... really, I'd just like to think that you good folk might think it a bit deeper than you appear to be doing.

Might I suggest, next sim session playtime, that folks have a look at a MLW, full flap, gear down, scheduled landing speed miss from the minimum .. with a failure just before .. and see just how different it is from the AEO miss .. chalk and cheese .. and then try it again at MTOW.

FlightDetent
21st Sep 2018, 18:27
I wonder about the LR quad airplanes, as for the popular SH twin:

A320/CFM (MTOW 77t, MLW 66t) on an ISA day and sea-level
with some precautions
.
.
@76,5t EO GA % = 3,9 with GA SPD = Vapp + 8kt
@90t EO GA % = 2,1 with GA SPD = Vapp + 13 kt

HPSOV L
21st Sep 2018, 23:45
JT

you make some excellent points but remember the OP was specifically referring to approach and landing at MTOW with one engine out and no other failures. I can only speak for the 777, but with that caveat I’d point out that a go around in that scenario would be at F5 which would provide a gradient to acceleration altitude equal or better than any takeoff configuration, given it’s initiated from a point a mile or so back and with no V1/VR gap.
I can’t prove that with graphs and numbers. However pilots do have to trust the company performance technical dept to develop and test generic strategies to cover most situations, and to publish any exceptions (KTM springs to mind). We simply don’t have the resources to create our own.
Having said that, I acknowledge I’m lucky enough to have worked for major well resourced airlines on modern large twins and my experience won’t be everyone’s.
Enjoying the discussion.

john_tullamarine
22nd Sep 2018, 01:17
I haven't played with Airbus or the triple-7 so I have no specific data. The main thing people need to think about, though, is the time (and distance) taken for their particular aircraft to accelerate from a full flap/gear down landing approach - OEI - to whatever escape configuration and speed is pertinent. So long as the thread engenders sitting back with a coffee or port and what-iffing it will have been valuable to the readership.

I do commend having a looksee at the exercise in sim playtime, though.