Ryanair B738 at Mallorca on May 29th 2014, wheel well fire indication

[Depone]

PMI to FMM. 148 pax. That's a short flight. Highly unlikely to be anywhere near MLW and a wheelwell fire warning would justify an overweight landing anyway. I suspect you're looking at creative reporting.

[captplaystation]

In my humble opinion of course, any use of the word "fire" where incidents are concerned reminds me of one occasion where time WAS of the essence (although the lack of urgency was not judged to have affected the eventual outcome ) . . . Swissair.


When I did my 1st jet rating on the DC9 back in 1988 my trainer in the Sim said to me "you have one thing to remember more than any other in any of the fire checklists . . . LAND"

I believe his advice was sound (although more than likely influenced by an occasion when an uncontained failure on a Viscount nearly burnt the wing off by the time they completed a very short circuit back to land on the x-rwy at LHR.)

[JW411]

Just as a matter of curiousity; in my long aviation career I never got near a 737. In fact, I have never flown an aircraft equipped with a wheel well fire indicating system (although I always thought the DC-10 could do with one).

My question; is the wheel well fire indication system listed in the MEL and can you despatch without it?

[DogSpew]

MEL

In answer to your question. Yes the Wheel Fire Detection System in accounted for in the B737 MEL.
You can dispatch with it inop, provided the BTMS (Brake Temperature Monitoring System) is operating normally. Or if BTMS is not fitted (or inop) then the brakes must be cool to touch before engine start.
Also, after takeoff the landing gear must be left extended for 10 mins (unless engine inop climb performance and/or ice accumulation is a consideration).
There is also a increase in fuel and trip time to account for the delayed gear retraction.

[muten]

Yes, you can go with it inop

M) (O) May be inoperative provided brakes are
inspected and are cool to the touch before engine
start.
NOTE: In case of engine failure after V1,
performance is the prime consideration, and the
landing gear should be retracted normally until
performance penalty with gear down is not a
problem. Pilots must consider the possibility of ice
accumulation on the gear associated with delayed
raising of landing gear or lowering landing gear
during winter operations.

[JW411]

muten:

I am very grateful for your reply. Thank you. I am not surprised.

[CaptClumsy]

We do have CCTV so we can see exactly what is going on.

[Aluminium shuffler]

As mentioned earlier, the fire det loop may be detecting a fire with the gear up but may not detect the same fire once the gear is lowered because the flames are directed away from the loop due to the changed airflow. The extinguishing of the light does not signify the extinguishing of the fire.

Regardless of whether I thought any fire, including a cabin fire, was extinguished, I would get a shuffle on to land at the nearest available. Any QRH fire drill that permits the flight to continue I would take umbridge with - you can't always determine if the fire is out, will stay out and hasn't already spread to somewhere undetectable. In my books, a fire will always result in an immediate landing; it's the one emergency that has no extra time beyond that for the quickest landing possible for troubleshooting. You get the thing on the ground ASAP and run what checks you can along the way.

I can see the point that Rat5 and 16024 are making, but if the fire is spreading so rapidly that these other systems are compromised in such a short time, then the airframe is going to unzip pretty quickly - better to skid off the end than disintegrate in flight.

[stator vane]

Flight deck drinks into the fire panel..

I had a wheel well fire event during two consecutive push backs on a 737-200 and was called later by the chief pilot that I had most likely spilled my coke on the fire warning panel since the mechanic found liquids and various goods in the switches there.

I told him i didn't drink the stuff and had watched Fate is the Hunter long ago and had learned not to make that mistake with any of my drink.

[Aluminium shuffler]

That sort of explanation seems plausible. You'd think, given the cost of the components on the pedestal, that they'd be splash proof by now, given how many times units have had to be replaced for spilled drinks and the lack of alternative locations pilots can drink their water, coffee and so on... It just shows the lack of intelligence in the design of so many aircraft systems and components, and how little the industry really learns from events.