737 fire handle - reset in flight?
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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
guys,the devil is in the detail and pedantic though it may be,Boeing do not refer to a 'fire handle' on the 737 series but an 'engine fire warning switch...'
all the best
all the best
Any guesses what happened next....?
Now if the ignition was still on and they energized the spray (or dribble) function then the fuel would simply dribble to the tailpipe and out on the ground. But if they still had a fair amount of air left in the compressor than the fuel would ignite in the combustor and quickly spread to the fuel dribbling into the tailpipe with a big swoosh, upon which they would put the engine on the starter and pray for rain.
These kind of trials are a whole lot more fun to do in real life than in a simulator since the results have a way of varying from bad to worse
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Hi guys
Hola BelArgUsa, as usual I enjoy reading your posts even when you was a member in another aviation forum.
Excuse my ignorance, it will be nice if you can give me some clarifications because I didn’t get the point of your “further step” (After "red light" is out 30 seconds later, test your fire detection system, light and bell, again for that engine).
Let say that after this step or procedure the fire detecting system is still intact/operant, do you continue your flight to your destination or do you divert to the nearest/adequate airport?
So I am wondering if it is possible to continue the flight after engine fire on B747 (I assume you are talking about this aircraft).
If the second fire extinguisher bottle is discharged, can this penalize the adjacent operant engine? (I don’t know how many engine fire extinguisher bottles are in B747, may be 2 bottles for each 2 adjacent engines???).
BigBusDriver, what’s the goal of such procedure in B 737 (testing fire detection system after discharging the second bottle).
I guess I am missing something, so please enlighten me.
Thanks
Regards
Hola BelArgUsa, as usual I enjoy reading your posts even when you was a member in another aviation forum.
Excuse my ignorance, it will be nice if you can give me some clarifications because I didn’t get the point of your “further step” (After "red light" is out 30 seconds later, test your fire detection system, light and bell, again for that engine).
Let say that after this step or procedure the fire detecting system is still intact/operant, do you continue your flight to your destination or do you divert to the nearest/adequate airport?
So I am wondering if it is possible to continue the flight after engine fire on B747 (I assume you are talking about this aircraft).
If the second fire extinguisher bottle is discharged, can this penalize the adjacent operant engine? (I don’t know how many engine fire extinguisher bottles are in B747, may be 2 bottles for each 2 adjacent engines???).
BigBusDriver, what’s the goal of such procedure in B 737 (testing fire detection system after discharging the second bottle).
I guess I am missing something, so please enlighten me.
Thanks
Regards
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1. Does not the QRH say fire the bottle if the handle is still red after fuel to cutoff? It is not a given, but conditional.
2. Testing the Fire system after completing the QRH is hardly going against the QRH. You have done as told, but then, for your own comfort, done a little extra which would appear not to effect any other system.
3. What I was taught, and pass on with enthusiasm, is "QRH complete" check Recall. There may have been a multiple failure and there are other issues to be addressed. It also tells you the status of the a/c and will help in the review phase of what to do next. "QRH complete" does not end the thinking process, but sadly that is what many seem to think. The classic is "no crew action required", only to find at the next landing the MEL grounds the a/c. Oops; the QRH says nothing about checking MEL in flight, but the C.P. will think it bad captaincy if you park the a/c at the wrong airfield and they have to spend mega bucks getting it home.
There is much the QRH doesn't tell us. It needs to be used with intelligence and common sense and airmanship.
2. Testing the Fire system after completing the QRH is hardly going against the QRH. You have done as told, but then, for your own comfort, done a little extra which would appear not to effect any other system.
3. What I was taught, and pass on with enthusiasm, is "QRH complete" check Recall. There may have been a multiple failure and there are other issues to be addressed. It also tells you the status of the a/c and will help in the review phase of what to do next. "QRH complete" does not end the thinking process, but sadly that is what many seem to think. The classic is "no crew action required", only to find at the next landing the MEL grounds the a/c. Oops; the QRH says nothing about checking MEL in flight, but the C.P. will think it bad captaincy if you park the a/c at the wrong airfield and they have to spend mega bucks getting it home.
There is much the QRH doesn't tell us. It needs to be used with intelligence and common sense and airmanship.
f/d -I've just checked in our FCOM and it's still engine fire warning switch -uk ng operator;you could still be right with your company but it definitely isn't fire handle!!
b/rgds
b/rgds
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Aerotech -
xxx
Regarding the engine fire warning light - if you have an engine fire, when the light goes "out" - maybe the light bulb "failed" - or the fire detection loop got burned-out by the fire itself, and the warning light would no longer test. Note that on some airplanes - such as the 747, you have double fire detection loops and double temperature gages which permit perfect monitoring.
xxx
As far as fire protection equipment - freon bottle - some 747 have 2 bottles only per wing (selectable to any of the engines on that wing) or the option of 2 bottles per engine (4 per wing). It is an option. Most 747 have the 2 bottles per engine (and also for the APU in the tail). For education and statistics - most engine fire warnings are bleed air related (overheat) and often "stop" when power is reduced. Other fires are electrical accessories on the engine, such as generator wiring. Some airlines have the policy "engine fire warning, continue engine fire procedure in any and all cases". Some other airlines permit to stop the procedure if the warning goes out (power reduction or power to idle = bleed air).
xxx
There is a "constant fire" inside operating engines...! - And a "tailpipe" engine fire (often on engine starts) cannot be extinguished by discharging a freon bottle. The only thing that you can do in a tailpipe fire situation is to continue to operate the starter motor. If you would operate the fire handle, it would stop bleed air to the starter, and make a tailpipe a worse situation if unable to crank the engine.
xxx
I hope that some "nerds" will have acquired some "system knowledge" here.
xxx
In a 3 or 4 engine airplane, should you have an engine fire, or engine failed, you can continue to your destination. I would, as per company policy, more than aircraft performance capability, recommend landing ASAP after an engine fire. Engine failure... well, that is ok. A BA 747s crossed the Atlantic with an engine out. Since it is BA, nobody will critique their decision. Would it be a US airline, most here would say "bunch of idiots, these Yanks"...!
xxx
Happy contrails
xxx
Regarding the engine fire warning light - if you have an engine fire, when the light goes "out" - maybe the light bulb "failed" - or the fire detection loop got burned-out by the fire itself, and the warning light would no longer test. Note that on some airplanes - such as the 747, you have double fire detection loops and double temperature gages which permit perfect monitoring.
xxx
As far as fire protection equipment - freon bottle - some 747 have 2 bottles only per wing (selectable to any of the engines on that wing) or the option of 2 bottles per engine (4 per wing). It is an option. Most 747 have the 2 bottles per engine (and also for the APU in the tail). For education and statistics - most engine fire warnings are bleed air related (overheat) and often "stop" when power is reduced. Other fires are electrical accessories on the engine, such as generator wiring. Some airlines have the policy "engine fire warning, continue engine fire procedure in any and all cases". Some other airlines permit to stop the procedure if the warning goes out (power reduction or power to idle = bleed air).
xxx
There is a "constant fire" inside operating engines...! - And a "tailpipe" engine fire (often on engine starts) cannot be extinguished by discharging a freon bottle. The only thing that you can do in a tailpipe fire situation is to continue to operate the starter motor. If you would operate the fire handle, it would stop bleed air to the starter, and make a tailpipe a worse situation if unable to crank the engine.
xxx
I hope that some "nerds" will have acquired some "system knowledge" here.
xxx
In a 3 or 4 engine airplane, should you have an engine fire, or engine failed, you can continue to your destination. I would, as per company policy, more than aircraft performance capability, recommend landing ASAP after an engine fire. Engine failure... well, that is ok. A BA 747s crossed the Atlantic with an engine out. Since it is BA, nobody will critique their decision. Would it be a US airline, most here would say "bunch of idiots, these Yanks"...!
xxx
Happy contrails
Scenario that I experienced.
Classic 747 crew with `real` F/E in the cruise for about 40 mins. with the APU shut down normally before take-off.
APU fire warning occurs. F/E tests both fire loops which are OK so order given to fire the APU bottle.
Fire light goes out ................. for about 2 minutes then comes on and stays on!
En-route diversion carried out with fire warning still on until short finals.
Maintenance find that the two fire wire loops which should have been run parallel to each other in the bay have been crossed over! Thus the vibration in flight rubbed the insulation off and gave BOTH a fire warning AND a valid wire continuity check! Sometimes you just can`t outguess bad servicing.
Classic 747 crew with `real` F/E in the cruise for about 40 mins. with the APU shut down normally before take-off.
APU fire warning occurs. F/E tests both fire loops which are OK so order given to fire the APU bottle.
Fire light goes out ................. for about 2 minutes then comes on and stays on!
En-route diversion carried out with fire warning still on until short finals.
Maintenance find that the two fire wire loops which should have been run parallel to each other in the bay have been crossed over! Thus the vibration in flight rubbed the insulation off and gave BOTH a fire warning AND a valid wire continuity check! Sometimes you just can`t outguess bad servicing.
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Hi,
BelArgUSA, thank you for your post.
I was expecting more details regarding the goal or the utility of your procedure or “further step”.
After reading your posts (11 & 49), I guess your concern is there might be a raging fire in the engine despite the red light is off and discharging 2 bottles and the fire may spread. Hence there is a need for testing the fire detection system to ensure the fire is extinguished.
If you perform a test and you find out the light bulb is good and the fire detection loop is working. Do you still land ASAP?
If you perform a test and you find out either the light bulb or the fire detection loop is not working. Do you still land ASAP?
Per company policy you recommend landing ASAP after engine fire. Do you take in account your procedure of testing engine detection system to decide to land ASAP or not? Or you land ASAP regardless of the result of test?
xxx
BigBusDriver and other pilots who fly twinjet, what’s the goal or the utility of testing fire detection system since you will land ASAP anyway regardless of the result of the test? (after the second bottle is discharged and engine fire light is off)
Feedback appreciated.
Thanks
Regards
BelArgUSA, thank you for your post.
I was expecting more details regarding the goal or the utility of your procedure or “further step”.
After reading your posts (11 & 49), I guess your concern is there might be a raging fire in the engine despite the red light is off and discharging 2 bottles and the fire may spread. Hence there is a need for testing the fire detection system to ensure the fire is extinguished.
If you perform a test and you find out the light bulb is good and the fire detection loop is working. Do you still land ASAP?
If you perform a test and you find out either the light bulb or the fire detection loop is not working. Do you still land ASAP?
Per company policy you recommend landing ASAP after engine fire. Do you take in account your procedure of testing engine detection system to decide to land ASAP or not? Or you land ASAP regardless of the result of test?
xxx
BigBusDriver and other pilots who fly twinjet, what’s the goal or the utility of testing fire detection system since you will land ASAP anyway regardless of the result of the test? (after the second bottle is discharged and engine fire light is off)
Feedback appreciated.
Thanks
Regards
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Most modern aircraft have fire handles which shut off the fuel at the engine (FMU, HMU, etc) .... as well as at the fuel spar valve (usually in the wing). These include the 767, 747-400, 767NG, etc. This will result in a very quick shutdown.
I had to pull a 747-400 fire handle as part of a maintenance check last year. I reset the handle, but, at the time, I didn't realise that I would have to manually reset the associated generator field breaker (by cycling the GCB switches). Perhaps this is what ASFKAP refers to? Loss of all main bus power?
Rgds.
NSEU
I had to pull a 747-400 fire handle as part of a maintenance check last year. I reset the handle, but, at the time, I didn't realise that I would have to manually reset the associated generator field breaker (by cycling the GCB switches). Perhaps this is what ASFKAP refers to? Loss of all main bus power?
Rgds.
NSEU
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I should clarify our procedure. It's not only done after the second bottle is discharged, but after the fire light extinguishes, whether that is after one or two bottles.
The utility of testing the integrity of the system is obviously to confirm that the light is out because the system is not longer detecting a fire, as opposed to a problem in the fire detection. If everything works as advertised a FAULT light should give an indication of a problem in the detection system, but in the case of a real raging fire, who knows what's going on out there.
Again, after any fire event the crew are going to proceed to the nearest suitable airport and put the thing on the ground, but how the crew handle that divert may be different depending on whether they have a secured engine or a fire that cant be contained.
The utility of testing the integrity of the system is obviously to confirm that the light is out because the system is not longer detecting a fire, as opposed to a problem in the fire detection. If everything works as advertised a FAULT light should give an indication of a problem in the detection system, but in the case of a real raging fire, who knows what's going on out there.
Again, after any fire event the crew are going to proceed to the nearest suitable airport and put the thing on the ground, but how the crew handle that divert may be different depending on whether they have a secured engine or a fire that cant be contained.
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Hi,
It seems that 747 are fitted with double fire detection loops and double temperature gages which permit engine monitoring in case of engine fire.
Are temperature gages basic or optional items on 747.
Are fire detection loops for detecting overheat and fire (as in some aircraft) or only for detecting engine fire?
Are you required to shutdown engine if the gage temperature reaches certain limit?
Are there other aircraft that are fitted with temperature gage to detect engine overheat/fire?
It will be nice if someone can post the complete procedure of engine fire for companies that require testing the engine fire system after the fire light extinguishes and after discharging one or two bottles (aircraft with 2, 3, or 4 engines).
Thank you for your feedback
Regards.
It seems that 747 are fitted with double fire detection loops and double temperature gages which permit engine monitoring in case of engine fire.
Are temperature gages basic or optional items on 747.
Are fire detection loops for detecting overheat and fire (as in some aircraft) or only for detecting engine fire?
Are you required to shutdown engine if the gage temperature reaches certain limit?
Are there other aircraft that are fitted with temperature gage to detect engine overheat/fire?
It will be nice if someone can post the complete procedure of engine fire for companies that require testing the engine fire system after the fire light extinguishes and after discharging one or two bottles (aircraft with 2, 3, or 4 engines).
Thank you for your feedback
Regards.
Warning Toxic!
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Disgusted of Tunbridge
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In no Boeing Engine Fire checklist that I know (737,747,757) is one required to check the fire warning system after discharging an extinguisher following a fire. Not required, not recommended and not done. Period. Our 747s did not have engine temperature gauges other than EGT and oil temperature. Only firewires.
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It seems that 747 are fitted with double fire detection loops and double temperature gages which permit engine monitoring in case of engine fire.
Are temperature gages basic or optional items on 747.
Are temperature gages basic or optional items on 747.
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Steve,
The Classic range of B-747s had individual engine nacelle temperature indicators which were in addition to the actual fire warning system. The follow up procedure following a fire warning and discharging one or both fire extinguishers as applicable was to check the Nacelle Temperature Indicator.
A reading above 7 units was a good indication that the engine fire had not been extinguished.
There was also a "Fault Light", which indicated a failure of one or both fire detection loops. A fault in both loops was also treated as a fire.
Does that help? Cheers.
The Classic range of B-747s had individual engine nacelle temperature indicators which were in addition to the actual fire warning system. The follow up procedure following a fire warning and discharging one or both fire extinguishers as applicable was to check the Nacelle Temperature Indicator.
A reading above 7 units was a good indication that the engine fire had not been extinguished.
There was also a "Fault Light", which indicated a failure of one or both fire detection loops. A fault in both loops was also treated as a fire.
Does that help? Cheers.
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ASFKAP,
In case of an overheat light, the QRH says reduce thrust until the light goes out and operate at the reduced thrust. If light remains on, carry out "engine fire, severe damage, separation" drill. This does require you to pull the fire switch . If the light is still on you activate the extinguisher.
I'm fairly sure your QRH won't tell you to pull the fire handle for a high nacelle temperature.....
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Fire detection 747-287B (JT9D-7Q)
Boeing AOM page 12.20.01
ENGINE NACELLE OVERHEAT
A nacelle temperature indication between 2.5 and 7.0 (amber range) should be monitored closely. NOTE A maintenance log entry should be made if nacelle temperatures stabilize in the anmber range or of A and B indicators do not agree within 2.5 units in the amber range.
IF NACELLE TEMPERATURE INDICATION IS APPROACHING 7.0 (RED):
Bleed Air Valve Switch... CLOSE
- Check VALVE CLOSE light illuminated.
Fuel Heat Switch... CLOSE
- Check OPEN light extinguished.
Nacelle Anti-Ice Switch... OFF
- Check VALVE OPEN light extinguished.
Engine Trust Lever... RETARD TO IDLE
- If nacelle temperature indication continue to rise, shut down engine.
See Chapter 2. INFLIGHT ENG FAILURE/SHUTDOWN
NACELLE FIRE DETECTION/FAULT LIGHT ILLUMINATED
Nacelle Temperature Indicators... CHECK.
- Identify engine and detector indicating in "red band"
Nacelle Fire Detector Switch... POSITION TO UNAFFECTED DETECTOR
- FIRE DETECTION and FAULT lights should extinguish.
Nacelle FIRE/FAULT Test Switch (Unaffected Detector) POS TO FIRE then FAULT.
- Position Test Switch of unaffected detector switch FIRE then to FAULT and check nacelle temperature indicator in the "red band" for FIRE TEST and for FAULT TEST. Fire warnings should occur in both positions.
- If unaffected detector test is normal, leave Detector Switch as position and continue normal engine operation.
- If unaffected detector does not test normally, position Detector Switch to the detector indicating in the "red band" and accomplish ENG FIRE SEVERE DAMAGE/SEPARATION checklist (Chapter 2 AOM or QRH)
Boeing AOM Page 12.50.01- 747-200/300 JT9D-7Q
Fire Protection Supplementary Information
Engines
Two engine fire detector systems are installed for each engine. Each system provides both relative temperature level indication and fault or fire detection capability and may be operated independently of the other.
xxx
For normal operations, both detector systems are required to indicate a fire warning. A fault in both detector systems will result in a fire warning and during single detector system operation, either a fault or a fire will result in a fire warning.
xxx
If an electrical short occurs, the affected nacelle temperature indicator will be locked in the "red band" and the necelle fire detector fault lights will illuminate. Selecting the operative detector system will extinguish the fault lights.
xxx
A detector open will NOT affect the operation of the detector system but will be evidenced by NO response to the fire test.
xxx
The fire detector system will respond to the following indications and warnings:
- Master FIRE warning lights will illuminate.
- Fire warning bell will sound.
- Engine FIRE switch will illuminate and remein illuminated as long as fire exists.
- Nacelle temperature indicator will be in "red band" and remein as long as fire exists.
NOTE
The fire warning will be locked on if an electrical short occurs during a fire. Selecting the operative detector will allow the warning indication to cease when the fire condition has passed.
xxx
Each engine has two fire extinguishing bottles which may be discharged separately into the nacelle area. Two nacelle discharge indicators, one for each extinguisher bottle, are located on the RH side of the engine strut. An indicator, when not intact, indicates that the associated bottle has been thermally discharged as well.
xxx
(end of Boeing AOM text)
Happy contrails
ENGINE NACELLE OVERHEAT
A nacelle temperature indication between 2.5 and 7.0 (amber range) should be monitored closely. NOTE A maintenance log entry should be made if nacelle temperatures stabilize in the anmber range or of A and B indicators do not agree within 2.5 units in the amber range.
IF NACELLE TEMPERATURE INDICATION IS APPROACHING 7.0 (RED):
Bleed Air Valve Switch... CLOSE
- Check VALVE CLOSE light illuminated.
Fuel Heat Switch... CLOSE
- Check OPEN light extinguished.
Nacelle Anti-Ice Switch... OFF
- Check VALVE OPEN light extinguished.
Engine Trust Lever... RETARD TO IDLE
- If nacelle temperature indication continue to rise, shut down engine.
See Chapter 2. INFLIGHT ENG FAILURE/SHUTDOWN
NACELLE FIRE DETECTION/FAULT LIGHT ILLUMINATED
Nacelle Temperature Indicators... CHECK.
- Identify engine and detector indicating in "red band"
Nacelle Fire Detector Switch... POSITION TO UNAFFECTED DETECTOR
- FIRE DETECTION and FAULT lights should extinguish.
Nacelle FIRE/FAULT Test Switch (Unaffected Detector) POS TO FIRE then FAULT.
- Position Test Switch of unaffected detector switch FIRE then to FAULT and check nacelle temperature indicator in the "red band" for FIRE TEST and for FAULT TEST. Fire warnings should occur in both positions.
- If unaffected detector test is normal, leave Detector Switch as position and continue normal engine operation.
- If unaffected detector does not test normally, position Detector Switch to the detector indicating in the "red band" and accomplish ENG FIRE SEVERE DAMAGE/SEPARATION checklist (Chapter 2 AOM or QRH)
Boeing AOM Page 12.50.01- 747-200/300 JT9D-7Q
Fire Protection Supplementary Information
Engines
Two engine fire detector systems are installed for each engine. Each system provides both relative temperature level indication and fault or fire detection capability and may be operated independently of the other.
xxx
For normal operations, both detector systems are required to indicate a fire warning. A fault in both detector systems will result in a fire warning and during single detector system operation, either a fault or a fire will result in a fire warning.
xxx
If an electrical short occurs, the affected nacelle temperature indicator will be locked in the "red band" and the necelle fire detector fault lights will illuminate. Selecting the operative detector system will extinguish the fault lights.
xxx
A detector open will NOT affect the operation of the detector system but will be evidenced by NO response to the fire test.
xxx
The fire detector system will respond to the following indications and warnings:
- Master FIRE warning lights will illuminate.
- Fire warning bell will sound.
- Engine FIRE switch will illuminate and remein illuminated as long as fire exists.
- Nacelle temperature indicator will be in "red band" and remein as long as fire exists.
NOTE
The fire warning will be locked on if an electrical short occurs during a fire. Selecting the operative detector will allow the warning indication to cease when the fire condition has passed.
xxx
Each engine has two fire extinguishing bottles which may be discharged separately into the nacelle area. Two nacelle discharge indicators, one for each extinguisher bottle, are located on the RH side of the engine strut. An indicator, when not intact, indicates that the associated bottle has been thermally discharged as well.
xxx
(end of Boeing AOM text)
Happy contrails
Last edited by BelArgUSA; 5th Apr 2009 at 11:42. Reason: Changing "shit" to "shut" (cleaning caca...!)
