Engine fire B737-300/900 QRH procedure
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Engine fire B737-300/900 QRH procedure
Hi All
Appreciate if I could get some opinions on this procedure..... Based on the B737 QRH....................
step 5
"If the engine fire switch or ENG OVERHEAT light is
illuminated:
Engine fire switch . . . . . Rotate to the stop and hold for 1 second
If after 30 seconds the engine fire switch or ENG OVERHEAT light stays illuminated:
Engine fire switch. . . . . . . .Rotate to the other stop and hold for 1 second
In the first instance when does the timing start for the 30 seconds then????.......
this is not clear in the QRH is this after confirmation of the fire bottle "DISCHARGE LIGHT has illuminated"???
thank you.
Appreciate if I could get some opinions on this procedure..... Based on the B737 QRH....................
step 5
"If the engine fire switch or ENG OVERHEAT light is
illuminated:
Engine fire switch . . . . . Rotate to the stop and hold for 1 second
If after 30 seconds the engine fire switch or ENG OVERHEAT light stays illuminated:
Engine fire switch. . . . . . . .Rotate to the other stop and hold for 1 second
In the first instance when does the timing start for the 30 seconds then????.......
this is not clear in the QRH is this after confirmation of the fire bottle "DISCHARGE LIGHT has illuminated"???
thank you.
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Well... I don't think that waiting more 10 or 15 seconds will do any further harm to the engine.
I just wait for the bottle discharge light to come on, then start the clock.
I just wait for the bottle discharge light to come on, then start the clock.
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Wait 30 seconds before discharging the second bottle. After rotating the Engine Fire Switch, always verify that the related BOTTLE DISCHARGE amber light illuminates. Therefore, the timing starts after you have confirmation that the first agent was discharged.
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The logic being that you allow 30 sec for the agent to do it's stuff, therefore the timing has to start at successful discharge. This will also lead you into confirmation that turning the handle has worked!
Whether you timed 28 seconds or 32 seconds, in real life it does not matter. In the sim even the most anal checker won't pick the difference, and even if he did what will he do - fail you?
In typical simulator scenarios, after the second bottle is gone the fire will either go out if the intention is to continue flying, or you will still be burning if the sim instructor wants you back on the ground quickly.
In real life if the fire warning goes out - whether after the first bottle or second bottle - assume nothing. Do a fire warning system test. If it does not test there is no guarantee that the fire is out (personal experience, related elsewhere in these forums). If you have reason to believe that fire is still present, land, NOW...if that means there is only time for speedbrake armed, gear down, flaps 15, add 15 knots, cabin alerted, so be it.
In typical simulator scenarios, after the second bottle is gone the fire will either go out if the intention is to continue flying, or you will still be burning if the sim instructor wants you back on the ground quickly.
In real life if the fire warning goes out - whether after the first bottle or second bottle - assume nothing. Do a fire warning system test. If it does not test there is no guarantee that the fire is out (personal experience, related elsewhere in these forums). If you have reason to believe that fire is still present, land, NOW...if that means there is only time for speedbrake armed, gear down, flaps 15, add 15 knots, cabin alerted, so be it.
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I think the OP meent something different, if you have to wait 30 seconds before you discharge the first bottle. The checklist covers 3 scenarios( actually four if you count the engine overheat light that directs you to this checklist if the overheat light does not go out), engine fire or severe damage or separation. In the last 2 you might not have a fire warning light.
If you have an engine fire, after you pull the engine fire switch and the the light stays on(which it probably will), you immediately discharge the bottle. Then, after 30 seconds, you discharge the second. You don't wait for thirty seconds after pulling the fire switch to see if the fire goes out by itself before discharging the first bottle.
If you have an engine fire, after you pull the engine fire switch and the the light stays on(which it probably will), you immediately discharge the bottle. Then, after 30 seconds, you discharge the second. You don't wait for thirty seconds after pulling the fire switch to see if the fire goes out by itself before discharging the first bottle.
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Mach E Avelli
As a side note...
"In real life if the fire warning goes out - whether after the first bottle or second bottle - assume nothing. Do a fire warning system test." I never knew this from a practical point of view.... do you mean to conduct the Supplementry procedures in the FCOM section 8???????????.......
please explain the meaning of what you wrote I am a bit unsure by what you mean and what are you looking for in the test.....
thank you
As a side note...
"In real life if the fire warning goes out - whether after the first bottle or second bottle - assume nothing. Do a fire warning system test." I never knew this from a practical point of view.... do you mean to conduct the Supplementry procedures in the FCOM section 8???????????.......
please explain the meaning of what you wrote I am a bit unsure by what you mean and what are you looking for in the test.....thank you
real life if the fire warning goes out - whether after the first bottle or second bottle - assume nothing. Do a fire warning system tes
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Originally Posted by downwind
As a side note...
"In real life if the fire warning goes out - whether after the first bottle or second bottle - assume nothing. Do a fire warning system test."
I never knew this from a practical point of view.... do you mean to conduct the Supplementry procedures in the FCOM section 8???????????....... please explain the meaning of what you wrote I am a bit unsure by what you mean and what are you looking for in the test.....
thank you
"In real life if the fire warning goes out - whether after the first bottle or second bottle - assume nothing. Do a fire warning system test."
I never knew this from a practical point of view.... do you mean to conduct the Supplementry procedures in the FCOM section 8???????????....... please explain the meaning of what you wrote I am a bit unsure by what you mean and what are you looking for in the test.....
thank you
If the test fails the fire might still be there, if it still works and the light comes on
No one is likely to fail a simulator check if they ONLY complete the items as per the FCOM, but then no one is likely to fail for applying extra precautions.
We should not be treating simulator exercises any differently to the way we would act in a real emergency. It appears that I am not alone in running a fire test after any fire drill.
But no, neither I nor other examiners I know REQUIRE it, because so far it has not found its way into the QRH.
Having said that, were you to dispute or belabour good advice you probably would do yourself no favours when the examiner graded the non technical skills section on your check form.
We should not be treating simulator exercises any differently to the way we would act in a real emergency. It appears that I am not alone in running a fire test after any fire drill.
But no, neither I nor other examiners I know REQUIRE it, because so far it has not found its way into the QRH.
Having said that, were you to dispute or belabour good advice you probably would do yourself no favours when the examiner graded the non technical skills section on your check form.
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I don't call that Airmanship.
I call that Making **** Up.
Boeing specifically recommends against further troubleshooting unless the situation is beyond the scope of the QRH.
Do the checklist and land the aircraft. Don't make **** up.
I call that Making **** Up.
Boeing specifically recommends against further troubleshooting unless the situation is beyond the scope of the QRH.
Do the checklist and land the aircraft. Don't make **** up.
We should not be treating simulator exercises any differently to the way we would act in a real emergency. It appears that I am not alone in running a fire test after any fire drill.
if so what are the resulting actions to be based on the result?
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In real life if the fire warning goes out - whether after the first bottle or second bottle - assume nothing. Do a fire warning system test. If it does not test there is no guarantee that the fire is out (personal experience, related elsewhere in these forums). If you have reason to believe that fire is still present, land, NOW...if that means there is only time for speedbrake armed, gear down, flaps 15, add 15 knots, cabin alerted, so be it.
Wasting time performing a fire test (albeit seconds) is just that, wasted time. It could also lead you into a situation of confirmation bias, where you now believe the fire is out and have more time that actually do.
Of course you should land ASAP whenever the QRH says so! Has anyone suggested otherwise?
But often in the simulator we see crews who don't apply any sense of urgency to a situation when cues are given to them that the damage really is a threat to their existence. A good one is to throw in a fuel leak, such as could be caused by shrapnel from the engine going through the wing. Some crews are quite happy to head for the holding pattern for a detailed approach briefing, all the while losing fuel at an alarming rate.
Others will blithely start cross feeding to the good engine even though the asymmetry is all wrong. Some will go for a full approach with the fire warning still illuminated, rather than cut it short. One can only hope that in a real situation fear for survival would trigger more decisive action.
I won't relate in detail my personal experience on another type with a similar fire detection system to the older Boeings here, as it is to be found elsewhere. Suffice to say, new aircraft out of the factory only a week, faulty combustion chamber, very intense flame, warning system disabled within seconds, leading initially to thinking perhaps the warning was spurious. Fortunately fire was visible from the cabin so both bottles were discharged despite no warning in the cockpit. From the initial very short indication to recognition that it was for real, to action commencing was less than a minute, yet considerable damage was done, including almost burning through some vital engine control linkages.
Some years later I had the pleasure of completing a Type Rating with an American Check Airman who had flown in excess of 30,000 hours. This guy had done a lot of work on early wind shear escape techniques for jet aircraft, so was no student pilot big on theory small on practice. During simulator training he also recommended a fire test after the drill. He had either experienced a similar event, or thought about the possibility.
The QRH does not call for cabin crew to be asked to look for signs of damage either, but if you had a fire/severe damage situation, after completing the drill would you not have someone look and report or send the F/O back if workload permitted? The QRH is only one part of managing emergencies and certainly does not prohibit further investigation, though of course one would be ill advised to start throwing extra switches or resetting circuit breakers.
After a fire or severe damage drill, if crew reported that they could not see anything would that be confirmation bias? Only for someone who subscribed to the notion that ignorance is bliss. Most would still land ASAP, as per QRH. However, if fire was visible or fuel was everywhere except in the tank the term ASAP could take on a whole new degree of urgency.
But often in the simulator we see crews who don't apply any sense of urgency to a situation when cues are given to them that the damage really is a threat to their existence. A good one is to throw in a fuel leak, such as could be caused by shrapnel from the engine going through the wing. Some crews are quite happy to head for the holding pattern for a detailed approach briefing, all the while losing fuel at an alarming rate.
Others will blithely start cross feeding to the good engine even though the asymmetry is all wrong. Some will go for a full approach with the fire warning still illuminated, rather than cut it short. One can only hope that in a real situation fear for survival would trigger more decisive action.
I won't relate in detail my personal experience on another type with a similar fire detection system to the older Boeings here, as it is to be found elsewhere. Suffice to say, new aircraft out of the factory only a week, faulty combustion chamber, very intense flame, warning system disabled within seconds, leading initially to thinking perhaps the warning was spurious. Fortunately fire was visible from the cabin so both bottles were discharged despite no warning in the cockpit. From the initial very short indication to recognition that it was for real, to action commencing was less than a minute, yet considerable damage was done, including almost burning through some vital engine control linkages.
Some years later I had the pleasure of completing a Type Rating with an American Check Airman who had flown in excess of 30,000 hours. This guy had done a lot of work on early wind shear escape techniques for jet aircraft, so was no student pilot big on theory small on practice. During simulator training he also recommended a fire test after the drill. He had either experienced a similar event, or thought about the possibility.
The QRH does not call for cabin crew to be asked to look for signs of damage either, but if you had a fire/severe damage situation, after completing the drill would you not have someone look and report or send the F/O back if workload permitted? The QRH is only one part of managing emergencies and certainly does not prohibit further investigation, though of course one would be ill advised to start throwing extra switches or resetting circuit breakers.
After a fire or severe damage drill, if crew reported that they could not see anything would that be confirmation bias? Only for someone who subscribed to the notion that ignorance is bliss. Most would still land ASAP, as per QRH. However, if fire was visible or fuel was everywhere except in the tank the term ASAP could take on a whole new degree of urgency.
Last edited by Mach E Avelli; 21st Jul 2015 at 17:51.
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Been reading this one and had nothing to add - until now and that is to say I agree with Mr. Avelli. The more information at hand, the better equipped you are to handle a situation, whatever that may be.
Now there is a possibility of information overload - something that happens with automation these days when the computers can't settle in on the problem, but that's another kettle of cod.
Now there is a possibility of information overload - something that happens with automation these days when the computers can't settle in on the problem, but that's another kettle of cod.
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Interesting discussion. I'm not a pilot, but I am an engineer with experience designing commercial aircraft propulsion systems.
There are extensive fire detection instrumentation systems inside the nacelle of a commercial aircraft like a 737. But most nacelle fires are due to severe engine damage, and they are often fed by oil or fuel leaks. It is difficult for the fire suppression systems to extinguish these fires.
On the other hand, the engine pylon and engine systems are designed to survive largely intact for a 20 minute exposure to a nacelle fire.
There are extensive fire detection instrumentation systems inside the nacelle of a commercial aircraft like a 737. But most nacelle fires are due to severe engine damage, and they are often fed by oil or fuel leaks. It is difficult for the fire suppression systems to extinguish these fires.
On the other hand, the engine pylon and engine systems are designed to survive largely intact for a 20 minute exposure to a nacelle fire.
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It's always best to know the status of our machines. That, in my mind, includes an evaluation of the engine after a fire, severe damage, or separation event.
A consequence of training for this in simulators is that things one could, and arguably should, do, in the aircraft, are not possible. For example, in a reject for an engine fire, and after the appropriate drills, I would get the cockpit window open and lean out and have a look (or ask my copilot to do so if it's on his side). When airborne, and assuming one doesn't have the misfortune to be flying a loaded freighter or at night, a visual inspection, ideally with images taken from the cabin with an iPad or similar, may be of great value.
That aside, I would agree with most of what Mach has written, but also hold the advice about making stuff up in high regard.
I can't help thinking that simulators with windows that can open, and some system of showing whats going on outside, might be valuable training aids. I know one TRE who has some photoshopped images on his iPad, showing engines in various states of disrepair, viewed from the cabin.
A consequence of training for this in simulators is that things one could, and arguably should, do, in the aircraft, are not possible. For example, in a reject for an engine fire, and after the appropriate drills, I would get the cockpit window open and lean out and have a look (or ask my copilot to do so if it's on his side). When airborne, and assuming one doesn't have the misfortune to be flying a loaded freighter or at night, a visual inspection, ideally with images taken from the cabin with an iPad or similar, may be of great value.
That aside, I would agree with most of what Mach has written, but also hold the advice about making stuff up in high regard.
I can't help thinking that simulators with windows that can open, and some system of showing whats going on outside, might be valuable training aids. I know one TRE who has some photoshopped images on his iPad, showing engines in various states of disrepair, viewed from the cabin.
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There is a huge difference between 'making stuff up' & maintaining a healthy suspicion of what is being presented to you.
I have found that many seem to be very happy to take the information presented by the aircraft systems as gospel these days & don't bother to check & cross-check. "Don't worry - the aircraft will tell you when something is wrong" seems to be the modern mantra. They seem to be content to deal with the issue when it becomes a problem, rather than head it off before it becomes a problem. Maybe I am old fashioned, but I call that a lack of airmanship.
I have found that many seem to be very happy to take the information presented by the aircraft systems as gospel these days & don't bother to check & cross-check. "Don't worry - the aircraft will tell you when something is wrong" seems to be the modern mantra. They seem to be content to deal with the issue when it becomes a problem, rather than head it off before it becomes a problem. Maybe I am old fashioned, but I call that a lack of airmanship.
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There is a scripted checklist for an engine fire. It wasn't dreamt up overnight.
If Boeing felt there was value in running a system test during that checklist, then they would say so. They don't. In fact, they say the opposite in the QRH introduction.
Prior to running a system test, good CRM directs that you first explain to the other pilot what you are about to do, and not do it until he/she is comfortable with it. Since you are going outside the checklist, good CRM directs that the other pilot will very likely question your actions and you will have to explain further. "Why are you conducting troubleshooting - we haven't even finished the checklist yet." The will result in distraction from the emergency at hand, cause possible delay to continuing the checklist and landing the aircraft, and (worst case) may result in you performing actions adverse to the continued safety of the aircraft due to conducting un-rehearsed and non-recommended actions to the amazement of the other pilot.
If Boeing felt there was value in running a system test during that checklist, then they would say so. They don't. In fact, they say the opposite in the QRH introduction.
Prior to running a system test, good CRM directs that you first explain to the other pilot what you are about to do, and not do it until he/she is comfortable with it. Since you are going outside the checklist, good CRM directs that the other pilot will very likely question your actions and you will have to explain further. "Why are you conducting troubleshooting - we haven't even finished the checklist yet." The will result in distraction from the emergency at hand, cause possible delay to continuing the checklist and landing the aircraft, and (worst case) may result in you performing actions adverse to the continued safety of the aircraft due to conducting un-rehearsed and non-recommended actions to the amazement of the other pilot.
I've never EVER been trained by Boeing OR Airbus OR Fokker to conduct a test of the Fire system during an Engine Fire warning or indeed after the warning stops.......
NO NO and NO.
FOLLOW THE BLOODY QRH NNC....
Land that Plane Maverick.....
I mean really.....
After the warning stops you conduct a test:---
1/ normal test result
or
2/ test fail
What does it mean anyway????? If the fire is out then do the loops reset?? I don't know???
Do you know???
Like I said, land the damn plane ASAP considering all factors relevant, it won't change your situation will it???
NO NO and NO.
FOLLOW THE BLOODY QRH NNC....
Land that Plane Maverick.....
I mean really.....
After the warning stops you conduct a test:---
1/ normal test result
or
2/ test fail
What does it mean anyway????? If the fire is out then do the loops reset?? I don't know???
Do you know???
Like I said, land the damn plane ASAP considering all factors relevant, it won't change your situation will it???
Last edited by ACMS; 27th Jul 2015 at 08:39.