B777 Engine Fire and Acceleration Height

[Airman2000]

Dear Fellas,

Suppose you have and acceleration and thrust reduction height of 1000' and you are taking off near you maximum take off weight with flaps 15.

You rotate and right after lift-off, bingo!, you get an engine fire. By 400' you start the drill nice and easy, but before you turn the fuel off the airplane starts accelerating and the thrust is now set to climb thrust.

You end up trying to accelerate with one engine inop, in very heavy weight and with climb thrust set. The result is a crappy acceleration.

Each instructor came out with a miracle solution of his own::}
- Set vertical speed near 0 (but, we are still with climb thrust...);
- Hurry the drill to switch the engine off before reaching thrust reduction (but, we risk messing things up);
- Hit TOGA after CLB is announced (so we get roll mode=TOGA, have to switch it back to LNAV, more thust is added complicating rudder control, and you risk exceeding the fixed derate thrust limit);
- Disconnect A/T in order to freeze the take off thrust were it was (looks weird, but you don't risk exceeding any derate limit);
- Hit the Init Ref and reselecting GA power (again, there is the risk of exceeding the fixed derate limit)
- Use thrust reduction as a function of flap settings on take-off ref (but we risk flying TOGA to 3000' when we are flying any noise abatment, and operating sistematicaly with high EGT will do no good for your engines...)
- Use a higher acceleration height (but you can have a fire anytime between V1 and Flaps up, and again, you end up trying to accelerate engine out with climb thrust..)

Any ideas? Does anybody knows what Mr. Boeing think of that? Or we simply should accept to accelerate with climb thrust and one engine out?:ugh:

Thanks in advance!

[lion-g]

Hi,

First of all, the performance calculated are catered for OEI. Therfore, if you are allowed" to takeoff by the software, therotically, it is safe to continue on CLB thrust.

However, at the extreme end of the performance, we definitely wants to get away from ground as soon as possible.

Here's what I used to do on the 777,

- Engine Fire at 400ft AGL ....
- Engaged AP if allowed !!
- Carried out the drill ! Once we retard the thrust lever on fire, we TOGA the other one immediately if we feel that additional power is needed. (It takes less than 2 sec to push the TOGA button while the PM is reading the next step of the EICAS.)
-accerlaration comes in ONLY we have secured the engine( that is put out the fire and we have a 10min allowance on TOGA power in case of OEI.

Noise abatment and all other regular ATC requirements are thrown out of the window once you have an emergency.

By exercising good airmenship, should the need of TOGA power be needed, just use it. We can't put a blanket on this, for example, a very light 772Er might have VMCA issue. Further more, since you are on very heavy weight T/O, your thrust might be very close to TOGA power as well.

Just my 2 cents worth, haven't flown the 777 for a year or so, do correct me if I am wrong.

Cheers,
lion-g

[fdr]

TOGA is a simple option which also brings attention to the desired roll command for EO SID requirements.


fdr