Complacency in crew handling of engine fire drills.

[Hudson]

Picked up an old 1969 flight safety magazine the other day and read about the Boeing 707 that experienced an engine fire in No 2 engine, 20 seconds after lift off from London Heathrow.

1.5 minutes after the the fire started, the engine fell off, however the fire continued to burn in the pylon area due to fuel pouring through a fractured pipe. This fuel was fed by the booster pumps at a rate of 50 gallons a minute.

The crew had omitted to pull the No 2 engine fire shut-off handle.

The aircraft was landed safely after reaching 3000 feet and 225 knots, and to help bring the aircraft to stop in the shortest possible distance, reverse thrust was used on Nos. 1 and 4 engines down to a very low speed, which caused the flames to be deflected towards the fuselage.

In a previous Pprune thread I recall that someone initiated discussion on rejected take procedure in event of a fire warning below V1. The discussion centred on whether or not reverse thrust should be selected on the engine that displayed a fire warning.

Most argued that in the heat (I like the intended pun, that's why I put it in!) of the abort procedure, there would be little time for the captain to identify the engine on fire and also consider the ramifications of reversing that engine, if indeed it was still producing thrust. Most thought they would still reverse the offending engine in the interest of getting the aircraft stopped quickly.

There was healthy argument possibly because there was lack of guidance in the manufacturer's FCTM with regard to use of reverse on an engine on fire.

From the accident report there is no doubt that use of reverse on the adjacent engine of the 707 fanned the flames towards the fuselage. Despite quick reaction by the Fire and Rescue Services, four of the 116 passengers and one stewardess were overcome by the heat and smoke and did not escape from the aircraft which was largely destroyed.

There remains the matter of the time interval from the first indication of fire in the No 2 engine and when, with part of its mounting pylon, it fell from the aircraft. It was 1.5 minutes. Granted the crew had failed to pull the fire handle in that time or fire an extinguisher.

The figure of 400 feet as a typical minimum safe altitude after take off is quoted in various manufacturer's manuals before the first action is taken to fight the fire. Under certain weight conditions it could take twin jet on one engine a long time to reach 400 feet - maybe even 45 seconds. The accent on careful considered reflection when dealing with a fire warning has often resulted in delays up to 1.5 minutes from onset of fire warning to actuation of the first fire bottle. (all this seen during simulator sessions, I hasten to add).

An oft quoted argument is that while combatting a fire is urgent it doesn't really matter how long it burns for, because in the end the engine will probably let go and fall off the wing. Then all your problems are over because happily the fire disappeared with the departure of the engine. Coffee is ordered and a leisurely return via radar vectors and an ILS is made.

The 707 engine fire scotched that theory with someone forgetting to pull the fire handle and fire a bottle, thus leaving the fuel pumps to feed the fire right down to touch down.

Finally, the canned exercises feature of many operators simulator sessions can often lull participants into a false sense of security. Rarely is time allotted to gain competency in a speedy return to land following an unextinguishable engine fire after lift off. Surely it is in these sort of exercises that the true value of simulators can be realised

[BEagle]

"Surely it is in these sort of exercises that the true value of simulators can be realised"

Very true. And if airlines were run by experienced pilots, there'd probably be as much simulator emergency training as there is in the military.

But airlines are run by beancounters - and they won't countnenance anything which takes pilots off the roster unless they're compelled to. A mate of mine in SirRB's airline told me that he made the same point as you, to be rebuffed by some suit who said "If reducing simulator times means that we might have an accident, well, that's what insurance is for".

Barking mad!!

[Crowsnest]

Points taken.

I realise that what we are taught nowadays is the finer evolution of procedures descended from incident reports such as this (and from theoretical exercises in the aforementioned simulator), yet it is my humble opinion that unless panic had descended upon the flight-deck, "someone" forgetting to fire the bottles would be a situation unlikely to happen as;

1. The Crew would have already confirmed the effected engine and run the Memory Items.

2. These would have been backed up by the printed QRH or equivalent.

I do, however, accept the assertion that in a heavy a/c on a hot day with one engine out, the rate of climb might have a fair bit to do with the curvature of the Earth.

By the time, in the worst case, the QRH had picked up the belated firing of the bottles and the second bottle had been fired after the realisation that the fire had not been extinguished, the elapsed time could well be in the region of two minutes.

The question is; how long do the fusible plugs (or equivalent) last, and would it be safer to cut corners in safety (confirmation of the engine, flap retraction on schedule, climb to MSA and backup drills) by splitting the attention of the Crew while the PNF does an early extinguishing drill?

I believe the second question answers itself, and that until a fully automatic Fire extinguishing system is fitted this may be the way it stays.

A degree of operational inexperience in such matters is admitted and comments are welcomed.

[411A]

Have worked for airlines that had two different thoughts on the matter.
1. Shut the engine down, and carry out drills at 400agl...period.
2. Finish flap retraction, then carry out drills.
Personally favor the latter.
Suspect the B707 in question would have been just fine had the proper engine fire procedure been followed...ie: pull the fire handle.
Actually, this is rather basic.
If pilots can't do these rather simple exercises, how much easier can it be made?:confused:

[Crowsnest]

"If pilots can't do these rather simple exercises, how much easier can it be made?"


A. Computer, Pilot, Dog.

B. UAV.


Whilst in no way suggesting that any pilot worth his Salt is unable to pull a handle; at 4am on an Icy night with an Emergency turn, high terrain and an inexperienced F/O, it might take "The Crew" in their combined wisdom and experience to get it all done.

i.e: Check, Check and Check again.

[Stan Woolley]

On balance I still think I would (try to) use full reverse on both engines during a rejected take-off, I'm not clever enough to start choosing options and the reject is one of the few emergency procedures that has to be carries out quickly (and accurately of course).

The 707 under discussion had a fully developed fire outside the engine by the time they came back for a landing. I would have thought most fires causing a reject would not be developed enough to fan the flames onto the airframe in the vast majority of cases?

All the airlines I've worked for commenced the engine fire on take off drill at 400'agl, seems to be the norm in the UK at least (Boeing types) so can't comment on other ideas.

I personally haven't yet seen it but I've just been discussing a video shown at fire training where an aircraft sits for an extended period with an engine burning on the ground (with the fire engines in attendance). The crew do not evacuate the a/c and I believe the fire is eventually extinguished. This video seems to polarise opinions and highlight the different approach to some emergency situations that is taken in different parts of the world.

[lomapaseo]

Most of the lessons learned from the 1969 incident have been incorporated.

Yes the pilot should/must shut off the fuel in a reasonable time period.

Yes the pilot should use all available means to stopping the aircraft as an overrun is sure as hell to worsen things.

and finally the fire regulations now ensure that a suitable margin against burnthrough of a fire wall between the fuel and critical aircraft structure must be demonstrated to accomodate slow crew action.

However like all crew/aircraft interface problems there are assumptions made in the design of the aircraft.