Airbus Flysmart TO Perf EO Acceleration

[Smooth Airperator]

The Flysmart Takeoff performance calculated Engine Out Acceleration Altitude for most airports with no terrain considerations is 800ft AGL. What happened to the days of 1500 AGL as a rule? I keep on telling guys that this is simply a minimum and I can adjust it to a higher value (limited by TOGA time limit) if I wanted to. Seems we have a lot of monkey say, monkey do going on. I'm being asked "where is it written that you can change it?" It's common sense that you probably don't want to be accelerating at 800ft AGL out of LGW given 3 GA airfields in close proximity. Thoughts?

[vilas]

The Flysmart Takeoff performance calculated Engine Out Acceleration Altitude for most airports with no terrain considerations is 800ft AGL. What happened to the days of 1500 AGL as a rule? I keep on telling guys that this is simply a minimum and I can adjust it to a higher value (limited by TOGA time limit) if I wanted to. Seems we have a lot of monkey say, monkey do going on. I'm being asked "where is it written that you can change it?" It's common sense that you probably don't want to be accelerating at 800ft AGL out of LGW given 3 GA airfields in close proximity. Thoughts?
Many LCCs use 800 ft THR RED/ACC ALT where possible for fuel saving. 1500/3000 was for noise abetment. So it depends on company policy.

[FLX/MCT]

Does Flysmart not give you the max EO accel altitude limited by 10 min OEI TOGA thrust? As long as you respect it you should be fine with a delayed leveloff/ acceleration.

[AerocatS2A]

OP is talking about the EO ACC so fuel savings and noise abatement are irrelevant. Our EO ACC is 1500 minimum with 800 only applying to the all engines operating case.

Personally I think it best to enter the Flysmart EO ACC in the perf page. That way you have a readily accessible reminder of the minimum value. If you suffer an engine failure, there’s nothing stopping you from delaying the acceleration until you’re comfortable. There’s nothing saying you MUST level off at the EO acceleration altitude, you have to secure the engine and complete any turns anyway, but there’s also no good reason to actually change it to a higher value preemptively. Unlike the all engines operating case, the EO ACC altitude has no effect on anything in the cockpit , it doesn’t automatically increase the speed for example.

[TheEdge]

From Airbus FCTM, FMGES PREPARATION:

The engine-out acceleration altitude must:

Be at least 400ft above airport altitude;
Ensure that the net flight path is 35ft above obstacles;
Ensure that maximum time for takeoff thrust is not exceeded.


There are generally a minimum and a maximum one-engine-out altitude values.

The minimum value satisfies the first two criteria. The maximum value satisfies the last one.

Any value between those two may be retained.

The one-engine-out acceleration altitude is usually defaulted to 1500ft AGL, and may be updated as required.

[vilas]

I missed out the OEI acceleration altitude which obviously is different.

[Smooth Airperator]

800ft out of a busy international airfield just seems wrong. Airmanship wise.

[BraceBrace]

800ft out of a busy international airfield just seems wrong. Airmanship wise.

There is nothing wrong with 800ft. The problem in dence airspace is the SID that you won’t be following. From that point of, 800ft or 1500ft doesn’t make any difference, your track change is the main problem. Even worse, you’re forcing your crewmember to be non standard and you’re deviating from a ’calculated’ vertical path.

Seems more like a false sense of security. It’s not because you’ve been doing it for all this time’ all this time it was the safest option. We should learn from the past.

[AerocatS2A]

800ft out of a busy international airfield just seems wrong. Airmanship wise.
"Mayday, mayday, mayday, [callsign] with an engine failure, require tracking straight ahead, climbing 4000', standby for further."

[FlyingStone]

800ft out of a busy international airfield just seems wrong. Airmanship wise.

Most busy airports will at least have a good chunk of controlled airspace around them. I'd worry much more about some regional airports, where only the CTR is controlled.

FWIW, at a Boeing operator I work for, we don't have an option to select a different EO acceleration altitude, so we're stuck with what we have - default is 1000ft AAL, unless higher required to maximise payload.

[Jwscud]

Ask your technical department or fleet technical pilot. There are a vast range of configurable options under the hood in Flysmart+ which will have been evaluated and set by your Technical Managers of which this is one.

We set it to 1000’ agl minimum.

[Rico_Corp]

If you suffer an engine failure, there’s nothing stopping you from delaying the acceleration until you’re comfortable. There’s nothing saying you MUST level off at the EO acceleration altitude, you have to secure the engine and complete any turns anyway

FCTM is quite clear on this: “delay the (EO) acceleration only for the purpose to secure the engine”

I don’t see the completion of a turn or being “comfortable” as a valid reason to delay EO acceleration.