737 fire handle - reset in flight?
 

If an engine fire handle in a 737-400 is pulled (but not turned), can it be reset in flight to attempt a restart, or is it strictly a one-way system?

Thanks,

Dave.

Hi Dave,

it is possible to push in the Fire Handle. Nothing is latched.
All the Shutoff Valves (Fuel, Hydraulic, Bleed) move to open.
Restart of the Engine is Possible.

so long
Frank

Hola David -
xxx
Typical Boeing fire handle - shut down fuel, hydraulic, bleed air, electrical...
As a matter of fact think of this. In flight, your CFM-56 windmills.
Not too good for that engine driven hydraulic pump. They are expensive.
Maybe a good idea, to let some fluid "lubricate the pump" from time to time.
All that depends on the reason why you pulled the handle.
On the ground, in 747, we occasionally shut down the engines with these.
To see... if they work. Sometimes maintenance requests us to check them.
Some fuel valves sometimes fail to close, and engine runs on, and on, and on.
xxx
Brgds/
:ok:
Happy contrails

Often an excellent idea - With the mob I used to work for, that was tried on one of the 747's on engine #1. After twenty seconds or so at idle power (most people don't know it takes that long at idle after you pull the handle to get shutdown) the #2 engine quietly shut-down, with #1 still running away nicely.
Oh joy ..... :)

the #2 engine quietly shut-down, with #1 still running away nicely.

(a) which is why some of us mandate independent inspections for critical engine mx

(b) didn't the operator do operational acceptance checks after significant mx ?

.. red faces.

Not with that 'airline' they didn't..

That incident is but one of several 'they' have been caught out with.

Plus the usual things for these types of operators -

- co-signing independent inspections by the same person.

- doing phantom maintenance at the last moment on items that are about to expire their MEL time limit.

I guess that's a reason for me not going back there after my 'vacation' a couple of years ago!

BTW - Hi 18-Wheeler, how you doin' these days, long time...

Cheers...FD...:)

Having pulled the fire handle, why would you want to push it in again?
Is it a new procedure you have found somewhere?

Maybe it was the wrong one......

If you did pull the wrong one, it would be a fair call to reset it, and quick-smart before the boss finds out. Next action would probably be the CVR 'erase' followed by free beers to the co-pilot for the rest of his career.

But if you ever pull one in anger, DO NOT reset it at intervals in the interests of lubricating fuel pumps etc. unless you have a QRH that tells you to do that. I have yet to see one that does. If the problem was serious enough to shut the engine down, don't even think about a relight unless the other one develops a worse problem. Attempting to relight a cold-soaked engine could be a lot more costly than a seized fuel pump. Don't get creative.

On the B777, the fire handle closes the HP valve as well, so its like a normal shutdown.

On the BA Tristar there was a MEL item that had you pulling the fire handle on every shutdown. I believe it was with APU Bleed air inop. You shut down Nbr 3 eng on the fire handle, and maint then chkd that the HPSOV was closed when you reset it. Yes it took about a minute to shut down on the fire handle.

Attn - gas chamber...
 

Blind execution of procedures published in QRH...
xxx
The Q in QRH means "quick" (and dirty) solving of emergencies or malfunctions which require later reading and following further notes found in expanded check-lists in AOMs. Then, there is what is taught (or used to be taught before the days of modern worthless CBT programs) in classrooms.
xxx
Such attitude "I follow QRH - that is it - no more - check list completed" lead into the disaster of ELAL 747 cargo in Amsterdam by stalling the airplane because of extension of leading edge flaps on one side of the airraft, the other wing's leading edge being disabled, "as per QRH"... which Boeing quickly corrected after the accident.
xxx
I will give you gentlemen an example. You are familiar with the Boeing engine fire procedure. The tune of the procedure is silence the bell, pull the handle, shutting down the engine, then activate a fire extinguisher. If the "red light" goes out - you stop there. If the "red light" does not go out, 30 seconds later, discharge the second fire extinguisher. Agreed...? That is the end of the QRH procedure.
xxx
The crews I trained and briefed in my classroom and simulators learned a further step, not published on any QRH. After "red light" is out 30 seconds later, test your fire detection system, light and bell, again for that engine. There is a slight possibility that your detection system burned out and got disabled by the engine fire and resulting severe damage. There might still be a raging fire there on your engine, despite the red light being "out"...
xxx
You see, in Pprune, there are student pilots, and (highly) qualified line captains, some of which are/were TRE/TRI or training managers. So "stick to your QRH" and do not use your brains. This old dog can still teach tricks you would be surprised to learn.
xxx
:E
Happy contrails

Testing the fire system after a fire drill is one I teach as well. I have practical experience of just the very situation where the fire loop got taken out when a combustion can on a RR Dart blew and caused the fire warning to go away before the fire was out.
But like GC, I would not condone 'creative' departures from the QRH just for the sake of it. Not all pilots are particularly knowledgeable of systems and so the QRH is written for the lowest common denominator for good reason. It is when the situation is NOT covered by the QRH that one must use common sense and airmanship and whatever other resources are at hand. But in today's litigious society it would be a brave pilot that stepped outside SOPs and QRHs etc without compelling reason.

Both BelArgUSA and Mach E Avelli ( great name btw:ok::ok::ok:) speak lots of common sense.
I am a late 30's FO, aviation is my second career, fast learning about the 737, I get to fly Classic and NG, I always read with interst what BelArg USA, has to say, you should write a book!!!!

Reset cb's ?
 

I believe the fire handle will trip the generator cb and gene control relay cb.

Common sense vs QRH
 

The QRH is a tool that should be used in non-normal situations. Going against the QRH is a bad idea unless you are absolutely sure that you know what you are doing. It is written in blood.... Testing the fire system sounds like a good idea but I wouldn't do it myself since I don't have suffiicient technical knowledge about the fire system. As far as I'm concerned the fire test could just as well be disabled after turning the handle for that particular engine.

Being creative can be a good idea but there are plenty of more accidents when people have been creative than when they haven't. Furthermore, you need to be able to back up your actions in a court of law...

Naturally, the QRH doesn't cover all possible problems and it says clearly in the beginning of it. But being creative in an already serious situation that is uncalled for can prove devistating...

Some of you here do not have "sufficient technical knowledge". Well, thanks.
Confirms poor opinion I have of XXIst Century training product of graduates of 14 ATPL exams.
No wonder I rather take trains or rent cars in your part of the world.
xxx
In the good old days, we had 120 hours of initial classroom type training.
Systems knowledge, manuals study, procedures, performance.
Then simulator training, two weeks, then line training...
And many of us spent a few years as flight engineer before being pilot.
And often, many "this is not in the books" - "how would you troubleshoot this"...?
xxx
What do you do in initial and recurrent training...? Country club style...?
Cup of tea with biscuits, Earl Grey, certainly, in a cute little cup.
And AOM replaced by the Daily Mirror, with Flight Int'l to seek better jobs...?
Suggest improving your knowledge of airplane systems by reading Pprune.
It is available on the net - www.pprune.org - for free.
xxx
:(
Happy contrails

I quite agree, BelArgUSA.
For example recently I started a course on the A330 and much to my surprise there was hardly any information on the engines.
They were treated as a 'thing' that hung off the wings, and either they worked or they didn't - With checklists to suit both states.

I like everything I can about every part of the aeroplane.

18-Wheeler -
xxx
At times, I do not know if I should cry or laugh at what I read here...
I recall my purgatory (or inferno) of my first F/E 727 oral exam. - 1969.
Started day 1, at 09:00, lunch break 12:30-13:30. Finished evening at 17:00.
Day 2 was 09:00 again, completed oral at 12:30, was "lunch time".
Typical question - how many cycles per minute toilet flush operates...?
xxx
Did they tell you how many engines are installed on the A-330...?
Your exam question will be "how do they operate...?
Answer "B" - Good...
xxx
Brgds -
:eek:
Happy contrails

I have read this thread with great interest and I totally understand and respect where BelArgUSA is coming from...

BUT... it is a VERY dangerous area that you go into regarding 'Troubleshooting and being creative'. (I'm not specifically talking about the fire test post engine fire for the B737 I'm just talking in general).

I cant but help think you are a very experienced pilot but there are many pilots with far less experience than yourself here reading these posts. Troubleshooting is one thing but not sticking to the 'Emergency Checklist' is something totally different and if for whatever reason right or wrong, you will have to explain your actions... I would not recommend it to anyone!

Granted many pilots don't have the greatest technical knowledge of their aeroplanes but the emergency checklist/aircraft procedures have been thought through by many people (designers, engineers, pilots etc) and there are reasons why you do certain actions and particularly why you do them in a specific order.

Doing things out of order or getting creative without the 'approval' of the airline and manufacturers procedures, well your asking for trouble which may ultimately get you fired or worse case lead to an accident.

At the end of the day the pilot is not there to trouble shoot (I say this with a pinch of salt) like a flight engineer would per say. Back in the day aircraft and there systems were different and had different levels of reliability... there were many cases of what you speak of 'Not in the books tips and tricks' to solve a situation/problem and thats why many of us always preferred having 3 pilots and having the experience and technical knowledge of the flight engineer with us.

Times have changed with the improved reliability of a/c, 2 man flight deck, better systems and maintenance along with better crm practices, pilot training. The whole industry is learning and getting better hence why air travel is so safe. We do as we are trained because we are trained well and thats why our industry is the safest.

To finish given a serious situation DO what your trained to do!! This does not mean you stop THINKING! Common sense is always good practice along with airmanship. The time to think about doing things differently to what you were trained or actions not in checklist or against them is ON THE GROUND outside of the aircraft, not in the air.


Happy and safe flying!


Aka.




--------------------------------------

Experience is something you gain 3 seconds after you needed it!

I teach the 737 for a US Major Airline. Our QRH procedure for Fire/Severe Damage has Immediate Action Items (not memory items) that end with the second bottle discharge, if required. Then the crew is directed to the expanded QRH procedure, where the first step is to test the fire detection system.

AKA Fresh I think he's trying to [forcefully] highlight the vast differences between airmanship and procedures,so Now,...LISTEN TO THAT GENTLEMAN,...HE'S JUST TELLING YOU !!!!:ok:

What happens if ...... ?
 

Okay, let's get the ritual over. I am not a pilot (Booo!) I'm an Engineer (Hurrah!) I'm not an aeroplane engineer (Boooo!) but I am an engineer on very high tech equipment ( Hur ..... oh, all right then.)

This thread is very interesting from the SLF/Flight Deck Groupie (retired :{) point of view, mainly because of the responses from pilots. Which seem to be largely; 'Does it?' And then a sharp intake of breath followed by; 'Ooo, I wouldn't touch it - the checklist won't let you.'

Reading a forum like this is fascinating stuff, but its a bit like reading Welsh or Hindi - every now and then there's a phrase in English that helps you understand a bit of what is going on. All the rest is in TLA - Three Letter Acronym, but really, I shouldn't be surprised. I expect if you heard me and my mates talking shop, you'd get confused by the TLAs as well.:)

I take it that QRHs are the procedures, chiseled into tablets of stone, that guide you through the admittedly fantastically complicated machine that is a modern airliner. To follow them is divine, you say, but then you say; 'but keep thinking - use common sense'. To which I say Ahmen.

I was startled at the number of pilots on this thread who were clearly a bit surprised when 18Wheeler mentioned it takes about 20 seconds to shut the engine down after pulling the fire handle. Right there is good enough reason to at least push it back sometime, in the simulator, without it being part of an evolution, surely?

Is it not 'thinking and common sense' to know that, and know what happens if you push the thing back without discharging the extinguishers? Quite honestly, I don't think my engineering curiosity could be contained, if the procedure did not expressly forbid me from pushing the fire handle back again - assuming I didn't do it to put out a fire.

Okay, I've bared my soul and await the terrible flames. :eek:

Roger.

Mate, the QRH stands for Quick Reference Handbook, written by Lawyers for Lawyers and pilots who are just Dumb, me included:cool:.
Hell the dammed thing states that there are situations where the book will not help you.

A proper understanding of the aircraft systems is simply put airmanship.
I teach in Airframes and Systems and that is what I tell my students.
Once airborne you have the weather, and you have the plane and the aerodynamic laws and yourself and a colleauge. Ofcourse, rules of the air must be followed. But when the plane breakes down and is degraded, the rules don't apply anymore. In that case, knowledge is your best friend. Knowing that it takes 20 seconds to shut down an engine with the fire handles may be worth a lot when the time comes.

And knowing which systems affect other systems. In my case on the little Saab, the fuel is heated by prop gearbox oil. If we get a fuel temp low warning, the pilot with no particular interest in systems design may dive into the the checklist for "fuel temp low". In the mean time the prop gear box might fail due to lack of oil (hence lack of heating to the fuel) and this could have been easily averted by looking at the prop oil indicators as an instinctive reaction to the initial fuel temp low warning.

This kind of reaction isn't in any book. It requires an interest in what we are actually doing and an interest in our surroundings.

Bel Arg, you are truly a wealth of knowledge! Thanks for all the good tips and keep them coming!

/LnS

mutley320
 

I think you may have misunderstood some of the terminology along the way. It is the Genrator Breaker (GB) and Generator Control Relay (GCR) which will be tripped or opened when fire handle is pulled not Circuit Breakers, altough admittedly the circuit will definitely be broken! Point is that GB and GCR will close on fire handle reset, all things being equal.

Another point is that it doesn't in fact matter even if the fire handle had been turned in addition to being pulled, it can still be reset and engine restarted (depending on original fault of course). Turning the handle simply discharges the extinguishant (freon gas) into the areas external to the core. i.e. around all of the accessories which may have caused the fire warning. The detection system does not normally monitor the core (certain exceptions monitor turbine overheats but this is not affected by extinguishers). So no harm is done to the engine core by firing the extinguisher. HOWEVER it is definitely not recommended to attempt to relight an engine which has been shutdown following a fire indication unless a greater danger exists.

Rubik 101 asks See above caveat but I have always maintained that those poor guys in the Kegworth B737 incident would have lit a paraffin lamp if they could find one in the circmstances they found themselves in.

Private fear.
 

I'm sure Kegworth causes the hair on all pilot's necks to stand up, but it has also always given me a particular frisson of rather selfish horror. As an engineer, a life long lover of aeroplanes and an interested SLF, I have a recurring image of sitting in that 737, watching the engine spit out its innards. I know enough about aeroplanes and their engines - if you knew my surname, it might make you smile - that I am certain I would have known that one was not long for active service. My fear is; if I had spoken quietly to the cabin crew and asked them to tell the captain what I had seen ..... would they have believed me or would they have 'not bothered the flight deck in the circumstances'?

Were the crew obliged to land at East Midlands or could they have continued to Belfast? It has always seemed to me that if, at their maximum attained height, they had elected to go on, they would have needed power and thus found out about the genuinely failed engine when it was less critical.

I know 'what if's' are a little pointless, but its the way your mind works.

Roger.

It's the way they're made to work on the 747 Classic. The one in question was a GE CF6-50 powered contraption, (with the reversed wiring being done at a certain Chinese maintenance company, not the company I flew for) and the reason it took so long is because they are really intended to be used in-flight, where the fuel-flow is far higher and so they will run out of fuel much faster than they would at idle. As mentioned in another post, other aeroplanes have slightly different systems, such as the 777 which has another shutoff valve closer to the engine so it shuts down much faster - the negative side of that is that the fuel line from the wing down to the engine still has fuel in it.

Nope, gotta have them ground engineers doing it while aircraft is parked on the ground.
Classsic and NG that be. :ok:

quote : "After "red light" is out 30 seconds later, test your fire detection system, light and bell, again for that engine. "

in my present SOP, it is not my "switch" anymore at preflight, certainly not in flight !

If an engine fire handle in a 737-400 is pulled (but not turned), can it be reset in flight to attempt a restart, or is it strictly a one-way system?

Thanks,

Aircraft systems wise the simple answer to your question is "YES" the handle can be re-set in flight, and assuming there is no damage to the engine it can be re-started. Once the engine has started the tripped generator can also be brought back on line. (I have personally demonstrated this in flight)

As to why, and if you would do it is an operational decision and would depend entirely on the circumstances at the time. :cool:

Sorta on-topic - What happened with the BMI Kegworth 737-400 when they shut down the RH engine? They tried a restart so it would seem that they didn't turn the handle ... ?

Capt Inop
Explain please? You are suggesting G/Es have to reset a fire handle on the ground? Where did you get this? Are you mixed up with CSD disconnect?

Which is precisely why this sort of examination was quite superfluous and useless knowledge. I had the same crap on DC3's - knowledge of the torque strength of the rudder and trim cables - all by engineers who delighted in looking down at new pilots with scorn. Best thing that ever happened was to throw away this so called "chalk and talk" in favour of need to know as against nice to know. Hence computer based training for aircraft systems. Nothing wrong with pilots seeking out extra information to their hearts content - although it was not necessary for the purpose of flying the aircraft safely. It was the trouble-shooting experts on the ground and in the air that resulted in the death of all aboard the MD80 that had the stabiliser jack-screw defect.

Time to get the report out and review it :)

Timing and conditions of a restart attempt are critical. Too little time and too little speed doom the attempt. If they had realized soon after they shutdown the wrong engine then a restart attempt would have been successful on the good engine. But since the flight conditions were such to keep the bad engine docile (vibs went away) they didn't realize their mistake until they spooled the bad engine way up for landing and trashed it. By then there was too little time and airspeed to restart the good engine. I don't believe that the fire handles entered into this until they trashed the bad engine during landing, but the details are in the report.

Apologies
 

My apologies here, for getting "high blood pressure" with some of you, when I am facing the sad state of oversimplification by "modern initial training and system knowledge" as some of you receive with your airlines. Although a line pilot, I got involved with all phases of pilot training, from aircraft systems or performance, to CPT procedures, simulators and line training of both pilot and flight engineers. And I got excellent training myself, not only from PanAm, my original airline, but also with other operators for which I provided contract training in various parts of the world. When I gave an oral exam to a newly qualified on an aircraft type, I always included these "nice to know" questions even if not published, or part of our SOPs.
xxx
None of the "techniques" I mention, or discuss, are meant to deviate from your SOPs, nor were "invented" by me, but are the result of years of training and research, and comparison of procedures adopted by other airlines. The training staff of airlines often get together with other instructors within the airline, or other airlines, or even the manufacturer (Boeing for me) to improve flight safety and reliability of the airplanes we operate.
xxx
I owe my knoweldge to numerous captains and engineers that I flew with during my many years - 1969 to 2008 - that is 39 years, with airlines. All I do here is pass along to those of you who want to know, the "how and why" of airplane everyday operations, that I learned myself from experienced aircrews from many airlines and many nations. Again - none of my recommendations are against your SOPs, they are merely "techniques".
xxx
An anecdote, to give you an idea, of a situation I faced a few years ago.
xxx
An airline (aircraft type is irrelevant) had a procedure where the engine normal ground start was performed with ignition on "both A and B" systems (or ignition "1" and "2" selected together). Fine and dandy. I had learned otherwise with PanAm, where we selected one ignition system only for start. I was training the crews on contract, and had an argument with their chief instructor (in a simulator) as I "deviated from their SOP" which called for both ignition to be selected "to get a better start"... The issue was brought to the chief pilot, and got accused to deviate from SOPs. I explained my position to the chief pilot.
xxx
The selection of one or the other ignition system is aimed at troubleshooting potential system failures (failed igniters, or ignition systems) prior to a flight. Suppose you fly in turbulence, and due to ignition time limitations, you select one system for a few minutes, then the other in turn. How do you know that "the other system works properly"... If you start engines with "both ON" you would never know, would you...?
xxx
Obviously, that airline tried to avoid dispatch delays (the decision of the management, not the pilots), to be sure that the planes "go on time". Of course, if you flame-out an engine in turbulence, is not the problem of accountants, it is a pilot problem... and flight safety.
xxx
So, I made my point to the chief pilot, who agreed with me, and also agreed to let me teach the technique of "single ignition start" and.. later, their SOP was even changed to reflect that technique, which became a normal "procedure" for them.
xxx
For the last 10 years, I was a training manager, and was the final authority as to change procedures... Since my retirement, I have been replaced by CBT, DVDs and computers. I see new editions of FCTMs and other manuals reduced from 600 pages, 2 volumes, to 150 page and thin binder. Saves on weight, paper and rain forests. Even though in my rocking chair since November, I constantly receive calls for training issues or recommendations... for free. Sounds like they miss me... If you dislike my recommendations, or you claim they are conflicting with your airline's SOPs (they know better than me), just ignore my recommendations, you receive their paycheck, not me. I just try to help you all, not to become one of the aviation statistics...
xxx
Again with my apologies, and best regards -
:ok:
Happy contrails

Will do, simply if you pull the fire handle in flight on a B737 you are not
gonna restart that engine again on that flight.
That's the reason why i never shut down an engine that can push it's own weight within the flight envelope, egt, wibs and even running at flight idle it's gonna provide me with hydraulics and electrics.:cool:

Well if the greater need arises, you should be aware that resetting the fire handle will allow normal access for restart, not as the impression you gave that it needs to be reset on the ground.

Quoting 18-Wheeler.

Just so we don't get confused with the initial airplane (737) the handle (on the 737) will only close the engine fuel shutoff valve. That's why the QRH tells you to shutdown the engine start lever first. If you wouldn't the engine would, indeed, continue to run for another 10 to 20 seconds because of the remainig fuel still present in the fuel system.

Well mr toxic guy. The way that i understads it you have downgraded from the allmighty B747 to the much simpler 737.

Having flown the Caravelle, the early versions of the DC9, and the very early versions of the B737 vithout a FMC, i'm telling you: Know your systems. And when you do you can come here criticicing me.

The only criticism is that you have posted misleading information!
Quite wrong. And quite what does what I fly have to do with it? Remove this nonsense and all will be sweetness and light again.