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Eng out accel height?

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Old 23rd May 2018, 06:25
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Eng out accel height?

What is normally EO accel ht.
in your company and which fleet?
For me is 400ft / B777
Just wanna know for some idea.
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Old 23rd May 2018, 06:41
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1500 feet by default for us. 400 feet is the strict minimum but we never use it. A 320 Family.
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Old 23rd May 2018, 06:44
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777 company policy is 1000’. FAA min is 400’
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Old 23rd May 2018, 07:39
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We use 1500ft as default, but some airports with specific geografical issues may require something higher. Like Quito for example. We use the 400ft number as a triggerpoint to perform recall items etc. Below that all the attention goes into flying the aircraft. B744.
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Old 23rd May 2018, 08:11
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Engine secure first then level off not below 1,000' in mine
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Old 23rd May 2018, 08:53
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400ft seems scaringly low. It is not necessarily a level acc height but in most heavy transports the height at which you reduce rate of clb in order to accelerate & clean up. Do that, in a 777 with terrain around, you would probably hit something. Thread opener Toung, pop into your Fleet Office & get them to re-look. Might save a few bent airframes.
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Old 23rd May 2018, 08:57
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600’ for a BAe146 (relevant? No .) Sometimes higher if terrain requires it.
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Old 23rd May 2018, 09:05
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Slowjet, the job of the airline’s performance department or contractor is to ensure that accelerating at the acceleration height doesn’t result in ground impact.
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Old 23rd May 2018, 09:16
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Do that, in a 777 with terrain around, you would probably hit something.
Isn´t that exactly why one needs to do an analysis for every departure and not just use a generalized one ? To take terrain into account ?
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Old 23rd May 2018, 10:37
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Most airlines it's a 1000 feet.
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Old 23rd May 2018, 13:20
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1500 feet. (B777)
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Old 23rd May 2018, 13:49
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Originally Posted by His dudeness
Isn´t that exactly why one needs to do an analysis for every departure and not just use a generalized one ? To take terrain into account ?
Absolutely for Part 121, terrain and other obstacles. And, because of terrain at some locations, the acceleration height may be different than what a particular airline typically uses.
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Old 23rd May 2018, 15:13
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Company provides an airport specific (and runway specific) acceleration altitude and minimum turn altitude for every scheduled and alternate port.
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Old 23rd May 2018, 15:17
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In accordance with aero data or other tailored performance provider acceleration and flap retract from V2 is no less then 1000' then climb at VFTO. If a complex special departure procedure requires it a turn can be made at 400' but accel remains no less then 1000'. This is a U.S. CRJ/ERJ.
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Old 23rd May 2018, 16:10
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Eng Out Accel Height as dictated by originally BCARs in the UK and FAA rules in the States was set at between 400’ and 1500’ as standard. Companies can choose where they wish to place it, most seem to settle on either 1000 or 1500 aal. Some airfields dictate something different and the Perf A Calc takes all this into account.
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Old 23rd May 2018, 17:47
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Absolutely for Part 121, terrain and other obstacles. And, because of terrain at some locations, the acceleration height may be different than what a particular airline typically uses.
I´m a Part 91 dude (NCC - as I´m in EASA land) and we have to do it as well.
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Old 23rd May 2018, 18:11
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Originally Posted by His dudeness
I´m a Part 91 dude (NCC - as I´m in EASA land) and we have to do it as well.
2nd segment climb ... from 35ft ( dry Rwy ) screen height and gear up ends at 400 ft or accel ht, all a bit academic but that’s the calculation used to satisfy the 2.4 % 2nd segment climb performance requirements.
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Old 28th May 2018, 12:27
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Was looking at this the other day, does any body know if the standard 2.5% climb gradient includes a level off for accel?

For example if the missed gradient is %7 all the way to the missed approach alt, do you have to stay at vref+5 and not clean up until reaching the missed approach alt? or does that %7 include a level off at 400/800/1000ft?
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Old 28th May 2018, 12:46
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ejet3

You raise an interesting point. Missed approach climb does not include an acceleration segment. EO performance is focussed on the take-off phase. If commencing an approach EO and a missed approach is required, there are many different ideas among the pilot community as to what is a reasonable flight path to follow. But AFAIK very limited official guidance is available.

As in your example we can maintain Vref + ? ( V2 ) to the MSA however what if this exceeds the max thrust time limit? Be interested in other airlines methods of dealing with this? ( official policy, not just what everyone commonly briefs!)

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Old 28th May 2018, 14:15
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Originally Posted by RUMBEAR
ejet3

You raise an interesting point. Missed approach climb does not include an acceleration segment. EO performance is focussed on the take-off phase. If commencing an approach EO and a missed approach is required, there are many different ideas among the pilot community as to what is a reasonable flight path to follow. But AFAIK very limited official guidance is available.

As in your example we can maintain Vref + ? ( V2 ) to the MSA however what if this exceeds the max thrust time limit? Be interested in other airlines methods of dealing with this? ( official policy, not just what everyone commonly briefs!)
Normally, you would be at, or below, max landing weight. Plus, you presumably begin the OEI missed approach at, or above DA. So, you are in better shape than OEI just above V1 on takeoff. If you are doing a OEI overweight landing, you might want to avoid using an IAP that doesn't have a 2.5% clear missed approach procedure.
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