Engine fire B737-300/900 QRH procedure
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Training, in this case, covers the possibility of the detector system not being a perfect indicator of whether the fire's been quenched or not. There may not be a procedure, but gathering information is not prohibited. Why not see what say the loops post discharge?
The delay between bottle discharge is due to the slow reaction of the loops. They are gas-filled metal tubes connected to (sometimes overly sensitive) pressure sensors and the system can take a few moments to recompose after being torched by burning kerosene or engine oil.
The delay between bottle discharge is due to the slow reaction of the loops. They are gas-filled metal tubes connected to (sometimes overly sensitive) pressure sensors and the system can take a few moments to recompose after being torched by burning kerosene or engine oil.
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I don't believe that anybody is advocating running a fire system test in the middle of the memory items, or interrupting a checklist to do so. The suggestion was to do the fire test at some stage after the fire warning has ceased, in order to ascertain whether the fire has indeed been extinguished or perhaps the warning has stopped for other reasons. This is something I have never heard of before & never considered, but it does make a lot of sense to me after thinking about it for a while.
Perhaps some should endeavour to step away from the trees & take a look at the forest. And don't always hang your hat on the training you have received. Sometimes it is a case of the blind leading the blind. The status quo is not always correct & it is often wise to consider new things objectively, rather than just repeating the mantra - "we have always done it that way"
Perhaps some should endeavour to step away from the trees & take a look at the forest. And don't always hang your hat on the training you have received. Sometimes it is a case of the blind leading the blind. The status quo is not always correct & it is often wise to consider new things objectively, rather than just repeating the mantra - "we have always done it that way"
It does not make any sense to makeup your own checklists or such, what you think Airbus Boeing and Fokker didn't think of this? They don't deem it necessary.
The only time I might consider a test is if the Fire Warning came on for a few seconds and went out before I started the recall items. Then I might just ask myself what's going on and perhaps perform a test.
I just hope I'm not faced with that scenario, especially en route miles from the nearest Airfield.
The only time I might consider a test is if the Fire Warning came on for a few seconds and went out before I started the recall items. Then I might just ask myself what's going on and perhaps perform a test.
I just hope I'm not faced with that scenario, especially en route miles from the nearest Airfield.
vapilot2004,
I believe there is another fire detection system consisting of dual loop detectors consisting of Inconel tubes filled with a salt impregnated ceramic core and a Nickel wire. An AC power supply is connected to the Nickel wire and the Inconel tube is grounded. At low temps, the resistance of the core is high and the capacitance is low.
When the temp increases to a certain set temp along the length of the Fire Detector or a higher set temp along say 30cm of the detector, the resistance decreases and the capacitance increases allowing current flow to ground and actuating the Engine Fire Indication.
McHale.
I believe there is another fire detection system consisting of dual loop detectors consisting of Inconel tubes filled with a salt impregnated ceramic core and a Nickel wire. An AC power supply is connected to the Nickel wire and the Inconel tube is grounded. At low temps, the resistance of the core is high and the capacitance is low.
When the temp increases to a certain set temp along the length of the Fire Detector or a higher set temp along say 30cm of the detector, the resistance decreases and the capacitance increases allowing current flow to ground and actuating the Engine Fire Indication.
McHale.
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Thank you Cap!
The following is anecdotal evidence from one of our crustiest engineers. (Take with a few grains of salty ceramics?)
Gas loops are prone to false alarms, says he, due to their sensitivity and the placement calibration, but are less likely to fail a BITE test. Inconel (or capacitive Kidde) loops are fragile and can be a pain in the keester (his word) to install unmolested, however they tend to produce fewer false alarms.
Our guy was unable to say definitively which loops are installed on which airplanes, but I assumed the gas loops are on newer NGs and the Inconel goes all the way back to the Jurassic, but do not know this to be absolutely true.
Any chance you might? Cheers!
The following is anecdotal evidence from one of our crustiest engineers. (Take with a few grains of salty ceramics?)
Gas loops are prone to false alarms, says he, due to their sensitivity and the placement calibration, but are less likely to fail a BITE test. Inconel (or capacitive Kidde) loops are fragile and can be a pain in the keester (his word) to install unmolested, however they tend to produce fewer false alarms.
Our guy was unable to say definitively which loops are installed on which airplanes, but I assumed the gas loops are on newer NGs and the Inconel goes all the way back to the Jurassic, but do not know this to be absolutely true.
Any chance you might? Cheers!
vapilot2004,
Our engineers can definitely confirm that I too am from the Jurassic period, but with regards to the fire loops, they seem to think that it could be either operator specific or manufacturer specific. Hope this helps.
McHale.
Our engineers can definitely confirm that I too am from the Jurassic period, but with regards to the fire loops, they seem to think that it could be either operator specific or manufacturer specific. Hope this helps.
McHale.
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On a related question, say the fire warning light came on and you pulled the thrust lever back, then the warning light went back out. Would you continue the memory items per QRH or leave it at idle power?
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Thank you Capt McHale! You're from the Jurassic era? 
Procedure calls for stopping just shy of discharging the bottles.
Procedure calls for stopping just shy of discharging the bottles.
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back to the discussion on the fire test procedure after the fire QRH items have been actioned, can people please tell me if you would test with fault/inop or ovht/fire switch??????? and what are the indications you should be looking for on the overheat/fire protection panel relating to the 737-300/900 type. I am a bit confused about this point that one of the posters is talking about, as of now no one has told has ever told me about this for a FAR 25 style aircraft??
Well the fundamentalists will say that there is no requirement to check anything beyond what the bible says because the great God Boeing will ensure that nothing can go wrong go wrong if your prayers are offered up directly from the bible.
The atheists and agnostics among us will say believe in nothing, trust not entirely in God or His bible but cover your arse by checking everything to be sure to be sure.
You are looking for a failed test to indicate the possibility - however remote - that the lack of a warning is no longer confirmation that the fire is truly out.
What you do with that information is beyond the scope of the QRH because that document can not cover every eventuality and does not claim to cover every eventuality. That is why you get paid the big bucks. Anyone can read a QRH and unthinkingly follow procedures.
Capts Haynes and Sullenberger are prime examples of pilots who went beyond the QRH to save lives. There are others like the skippers of the Gimli glider and the topless 737.
The atheists and agnostics among us will say believe in nothing, trust not entirely in God or His bible but cover your arse by checking everything to be sure to be sure.
You are looking for a failed test to indicate the possibility - however remote - that the lack of a warning is no longer confirmation that the fire is truly out.
What you do with that information is beyond the scope of the QRH because that document can not cover every eventuality and does not claim to cover every eventuality. That is why you get paid the big bucks. Anyone can read a QRH and unthinkingly follow procedures.
Capts Haynes and Sullenberger are prime examples of pilots who went beyond the QRH to save lives. There are others like the skippers of the Gimli glider and the topless 737.
Last edited by Mach E Avelli; 31st Jul 2015 at 10:16.
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Sorry for the confusion here. I read a few posts above 'engine overheat light', and was answering according the QRH. Read again the posts and discovered people were discussing 'engine fire'.
The memory items are obvious.
The memory items are obvious.
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Hi,
Mack E Avilli, can you explain exactly what Capts Haynes and Sullenberger & the skippers of Gimli gliders and the topless B737 did beyond QRH to save lives?
Are there examples of pilots who went beyond QRH and caused incidents, disasters...?
Feedback appreciated.
Regards
Mack E Avilli, can you explain exactly what Capts Haynes and Sullenberger & the skippers of Gimli gliders and the topless B737 did beyond QRH to save lives?
Are there examples of pilots who went beyond QRH and caused incidents, disasters...?
Feedback appreciated.
Regards
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I am with Mach E Avelli here.
The ones who 'live by' the QRH probably did not read the Introduction section of it.
Airmanship is still an essential, but more and more hard to find part of flying aeroplanes.
To go even further, even SOP's can kill you, if exercised without critical analysis in some circumstances.
The ones who 'live by' the QRH probably did not read the Introduction section of it.
Airmanship is still an essential, but more and more hard to find part of flying aeroplanes.
To go even further, even SOP's can kill you, if exercised without critical analysis in some circumstances.
Last edited by latetonite; 1st Aug 2015 at 22:27. Reason: Spelling
Ok then experts:---
After a real Fire warning where the fire warning has gone out
What's the test supposed to show, Pass or fail?
What do you do if it passes or fails?
Is your thinking different?
Do you decide to hurry up and land or take your time?
Please enlighten me.....
After a real Fire warning where the fire warning has gone out
What's the test supposed to show, Pass or fail?
What do you do if it passes or fails?
Is your thinking different?
Do you decide to hurry up and land or take your time?
Please enlighten me.....
Last edited by ACMS; 2nd Aug 2015 at 07:48.
Fire indicated out, test shows warning system still good, it is reasonable to believe fire is out. But check for damage elsewhere anyway and land ASAP. ASAP still implies that you will be landing on an airport that will at least accommodate your aeroplane safely.
Test fails, suspect further damage and consider the POSSIBILITY that there may still be fire and act as if this is the case. It is all about understanding the relative seriousness of the latter possibility compared with the lesser probable risk of the former.
Uncontained fire or very severe damage MAY require a decision to land somewhere quite unsuitable (even unsafe in normal circumstances) but survivable, so could mean re-routing to minimise time in flight should the worst eventuate.
That is what they did with the Gimli glider, though with no fuel it was not likely to burn!
Capt Haynes had to 'invent' a new way of controlling an aircraft with thrust alone. It sure as hell was not in the QRH.
I believe that Capt Sullenberger went straight for the APU before getting into the rest of the QRH. It was out of sequence but they did not have time to work all the way through the QRH so needed to prioritise. Since then Airbus have probably rewritten the QRH but I am not an Airbus person so don't know for sure.
Test fails, suspect further damage and consider the POSSIBILITY that there may still be fire and act as if this is the case. It is all about understanding the relative seriousness of the latter possibility compared with the lesser probable risk of the former.
Uncontained fire or very severe damage MAY require a decision to land somewhere quite unsuitable (even unsafe in normal circumstances) but survivable, so could mean re-routing to minimise time in flight should the worst eventuate.
That is what they did with the Gimli glider, though with no fuel it was not likely to burn!
Capt Haynes had to 'invent' a new way of controlling an aircraft with thrust alone. It sure as hell was not in the QRH.
I believe that Capt Sullenberger went straight for the APU before getting into the rest of the QRH. It was out of sequence but they did not have time to work all the way through the QRH so needed to prioritise. Since then Airbus have probably rewritten the QRH but I am not an Airbus person so don't know for sure.
Last edited by Mach E Avelli; 2nd Aug 2015 at 09:51.
Sorry mate I don't believe your analysis is foolproof.
The actual Fire that the detectors detected will most likely damage the detectors won't it?
I would expect that the test for that Engine would not pass.
In this case you may be led down the garden path to land at an Airfield you don't really want to be at.
The Airbus ECAM has a RED LAND ASAP with a Fire and that about covers it....
There are other things you will do to ascertain the state of the Fire and :--
LAND ASAP.
I still say that both Airbus and Boeing would have considered this possibility ( everything they do is with litigation in mind and ass protecting ) and decided against it for very good reasons not least being it may not be a reliable check of the system or indicate the level of damage to the Engine.
Oh and yes most definitely there is a time and a place to vary procedures as required, as has been shown many times ( as indeed Airbus and Boeing advise )
The actual Fire that the detectors detected will most likely damage the detectors won't it?
I would expect that the test for that Engine would not pass.
In this case you may be led down the garden path to land at an Airfield you don't really want to be at.
The Airbus ECAM has a RED LAND ASAP with a Fire and that about covers it....
There are other things you will do to ascertain the state of the Fire and :--
LAND ASAP.
I still say that both Airbus and Boeing would have considered this possibility ( everything they do is with litigation in mind and ass protecting ) and decided against it for very good reasons not least being it may not be a reliable check of the system or indicate the level of damage to the Engine.
Oh and yes most definitely there is a time and a place to vary procedures as required, as has been shown many times
( as indeed Airbus and Boeing advise )
Last edited by ACMS; 2nd Aug 2015 at 10:07.
Nothing in aviation is foolproof. I would be the last to claim any foolproof analysis skills. In training I merely seek to get pilots thinking outside the square.
A Yank I knew many years ago worked out that Fokker's emergency gear extension drill for the F 27 could fail to do the job under certain circumstances. He wrote to Fokker about it, and offered an alternative procedure. They ignored it. I did not ignore it and in a memo advised my pilots to consider this guy's unofficial drill if the approved drill failed because it made so much sense. Sure enough, one day an aircraft had a problem with the pneumatics and the gear would not come down using the approved procedure. So the pilot did the unofficial drill. It worked.
A Yank I knew many years ago worked out that Fokker's emergency gear extension drill for the F 27 could fail to do the job under certain circumstances. He wrote to Fokker about it, and offered an alternative procedure. They ignored it. I did not ignore it and in a memo advised my pilots to consider this guy's unofficial drill if the approved drill failed because it made so much sense. Sure enough, one day an aircraft had a problem with the pneumatics and the gear would not come down using the approved procedure. So the pilot did the unofficial drill. It worked.
Last edited by Mach E Avelli; 2nd Aug 2015 at 10:34.