Eng out accel height?

[toung]

What is normally EO accel ht.
in your company and which fleet?
For me is 400ft / B777
Just wanna know for some idea.

[pineteam]

1500 feet by default for us. 400 feet is the strict minimum but we never use it. A 320 Family.

[motley flight crue]

777 company policy is 1000’. FAA min is 400’

[76-er]

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.

[xray one]

Engine secure first then level off not below 1,000' in mine

[slowjet]

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.

[AerocatS2A]

600’ for a BAe146 (relevant? No :).) Sometimes higher if terrain requires it.

[AerocatS2A]

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.

[His dudeness]

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 ?

[Start Fore]

Most airlines it's a 1000 feet.

[Long Haul]

1500 feet. (B777)

[aterpster]

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.

[AmarokGTI]

Company provides an airport specific (and runway specific) acceleration altitude and minimum turn altitude for every scheduled and alternate port.

[cappt]

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.

[Juan Tugoh]

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.

[His dudeness]

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.

[Jack D]

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.

[ejet3]

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?

[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!)

[aterpster]

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.

[RUMBEAR]

I don't disagree. However this question results in "normally" and "presumably" being included in almost all answers. I fly to many airports that don't have the standard 2.5% missed approach gradient. The charts also include the statement " MDA / DA based on 2.5% gradient not provided". Would should also say "hopefully" will not have to consider this situation for real!!

[john_tullamarine]

If you have a difficult runway approach, so far as the miss is concerned, then the ops engineers need to have a look at in a manner similar to the takeoff situation.

On another point, for takeoff, where terrain dictates, one can schedule a turn from runway head and 50ft.

[JammedStab]

If you have a difficult runway approach, so far as the miss is concerned, then the ops engineers need to have a look at in a manner similar to the takeoff situation.

On another point, for takeoff, where terrain dictates, one can schedule a turn from runway head and 50ft.

True, we used to have a couple of airports with engine-out procedures that started at 50 feet with a 15 degree bank through 180 degrees of turn to avoid close-in high terrain. I believe the company makes the choice of what altitude they want(or is it the manufacturer?). Over the years on various aircraft, I have seen 400, 600, 800, and 1000 feet. But on the most recent aircrat with 1000 foot acc heights, there are specific runways with slightly higher atitudes. The interseting thing is that the OPT might adjust them slightly based on the final numbers as compared to the original calculation, so you might want to double check the acc altitude after getting the loadsheet numbers into the performance calculator.

[ejet3]

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.

Say your at MLW or over! either way you need to have something to hang your hat on in court.

I think the safest option would be to fly the jepp missed approach and clean up at the accel altitude that's in OTP (Boeing) or the 1 inop procedure (CDP)? if your below the MDA/DA or can't met the missed approach gradients fly the 1 inop take off procedure (CDP) and clean up at that accel altitude.

Thoughts? goes for both 1 and 2 engine!

[aterpster]

True, we used to have a couple of airports with engine-out procedures that started at 50 feet with a 15 degree bank through 180 degrees of turn to avoid close-in high terrain. I believe the company makes the choice of what altitude they want(or is it the manufacturer?).
It's up to the operator. The manufacturers don't concern themselves with obstacle clearance, per se, or with the manner in which the takeoff path is flown. The manufacturers assure the aircraft with meet the Part 25 takeoff flight path at MTOW under optimum conditions, and provides OEI data for various weights, elevations, temperatures and runway lengths.

The operator then has to assure compliance with 121.189, or its equivalent. Many today now use the Part 25 takeoff path applied to AC 120-91, rather than the impossibly narrow lateral limits specified in 121.189.

AC 120-91:

https://tinyurl.com/ydd9e7zp

Large operators have their own planning and performance departments. Smaller operators often use contract planning and performance companies.

[aterpster]

Say your at MLW or over! either way you need to have something to hang your hat on in court.


Should be provided by the company for every approved IAP.