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Old 19th Sep 2018, 12:31
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john_tullamarine
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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.
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