Tail Pipe fire. Not memory item but should the pilot know what to do, anyway?

[Tee Emm]

The Boeing 737 QRH publishes the drill for Engine Tail Pipe Fire on the ground with no engine fire warning.

Now the wise pilot will have a good working knowledge of each QRH Non-Normal, even though he is not expected to know every word by memory. That is why there are some Non-Normals as Memory Items.

Looking at a pilot's general knowledge of the 737 QRH Non-Normal items, he was presented with the situation of a Tail Pipe fire shortly after the engine were shut down after a flight. When asked to complete the required actions without reference to the QRH, to put it bluntly he didn't have a clue. Further amplification is unnecessary. Yes - it is a non-memory item. But a fire is a fire is a fire, and I would have thought this alone would be sufficient for him to have a reasonable knowledge of the drills required. Was I expecting too much of this captain with thousands of hours on type?

Is it unreasonable to expect a broad knowledge of Non-Normal non memory items drills? Or is it a case of don't worry about a thing - its all in the QRH my friend so don't waste your time learning things you don't have to?

[BOAC]

I understand the philosophy is that with fuel shut off, and no fire warning, the burning is inside the engine only and that is designed to have burning inside, so there is no huge urgency. There is, of course one memory item unless that has changed?

BTW - what do you do if the APU is not running?

[F14]

I think many moons ago it was memory. But then they changed it, probably because people screwed it up (fired bottles, etc)

Question you need to ask is, what do you do if you have no APU bleed, or other engine bleed available? how can you motor ?

[Sciolistes]

Is it unreasonable to expect a broad knowledge of Non-Normal non memory items drills? Or is it a case of don't worry about a thing - its all in the QRH my friend so don't waste your time learning things you don't have to?

I think a broad knowledge is essential. But I also believe that only memory items or insignificant yet essentially normal but still non-normal checklist items (like altitude alerts - for example) should be done from memory.

But one should know what they are about to enter into before they start the checklist. The checklist is just detail that needs to be got right.

[BOAC]

if you have no APU bleed

- then you have to wait for the two Spanish firemen, HoseA and HoseB to attend.

[mad_jock]

Its the way the schools are teaching now not to remember any of the QRH apart from the memory items.

Even if you do know your meant to sit on your hands and wait until its run.

I can sort of see where they are coming from in Europe because of the number of 200 hour magenta line borgs on the line. The sop's and dealing with issues has to be tight otherwise they don't have a clue whats going on and the Captain is single crew as soon as they step a mm away from the book.

On my type its at the age that its inventing issues which were never considered possible when they wrote the QRH. If you don't know the systems your stuffed. And potentially making things worse by using the best fit QRH checklist.

[lomapaseo]

What symptoms are available to the pilot in the event of a tailpipe fire after engine shutdown at the gate?

Screaming passengers in the back?

A cabin call ?

A radio call ?

An engine temp indicator?

Should this key their response to a memory item ?

I would have thought that all this was taught when a pilot moved over to jets. Now with the question tunring up on PPRune I'm a little concerned, because in this case a fire is not a fire and we don't want passengers going down the chutes if they don't have to.

A quick pilot action is required to assess and control the situation.

[Checkboard]

A ground crew member doing this:

BALPA | Emergency Hand Signals to Pilots

[BOAC]

loma:

Screaming passengers in the back? - possibly

A cabin call ? - possibly

A radio call ? - less likely

An engine temp indicator? - unlikely

ADD - Groundcrew running away.

The biggest hazard is, as you have highlighted, inexperienced c/crew initiating an evacuation or pax panicking. Another one rarely seen (by me anyway) these days is the 'wet start' with clouds of smoke.

[mad_jock]

I don't even have a tail pipe fire QRH page on the TP331 presume because its a sealed oil system.

[Meikleour]

mad jock: what do you mean? I have always thought that a tailpipe fire was caused by excess fuel which has "pooled" in the tailpipe catching fire?

[mad_jock]

To be honest thats what I thought as well.

It just seems strange to me that TP's don't seem to have QRH page for tail pipe fire yet jets do.

We can get the fuel pooling with the fixed shaft ones if you turn and pull and then spin the props you can get a 30ft after burner effect coming out the back with a huge whoosh. Which can alarm the ground crew.

The only burnable stuff up there that I could think of was the bearing oil which we tend not to have as its a sealed system that very rarely needs topping up and when its does its usually because its coming out the gear box.

[Centaurus]

What symptoms are available to the pilot in the event of a tailpipe fire after engine shutdown at the gate?

In the 737 simulator, we initiate the exercise by the instructor banging on the side of the simulated fuselage and shouting "Tail Pipe fire and it is spreading flames below the engine onto the tarmac" There are enough clues there for the crew to take appropriate action. It is assumed the APU is operating and an aircon pack is on and the passengers are disembarking at the gate.

I must say it is often the case where the first officer will look wide-eyed at this news saying WTF and start to fumble for the QRH and often is unable to locate the correct page for up to a minute after the first warning from the ground staff bloke. Meanwhile the captain is telling him for Christ sake get a move on and sits on his hands apart from telling ATC he needs help quick.

There is a neat little paragraph in the 737 QRH that states: "The pilot flying may also direct reference checklists be done by memory if no hazard is created by such action, or if the situation does not allow reference to the checklist"

Now interpret that how you wish, but it seems to me that a tail pipe fire as described above, calls for swift action to prevent fire from spreading. In the simulator scenario set up by the instructor, all the captain has to do while the hapless F/O is diving into the QRH index page, is to switch off the aircon pack (s) check there is pneumatic start pressure and motor the engine until someone on the ground tells him the tail pipe fire has blown out. Sure, that is not a memory item but isn't this where good airmanship starts? Or are crews so inured to having a checklist to instruct them what to do, that a simple commonsense action of motoring an engine is beyond their ken. Fires wait for no man
Not forgetting the precaution of switching back on the anti collision light which should get those close to the aircraft scattering quickly as they associate the anti-coll light with impending engine start. And by the way, I recall reading somewhere that the internal components of a jet engine can remain hot enough for up to 20 minutes after shut down to ignite residual fuel.

[lomapaseo]

Not forgetting the precaution of switching back on the anti collision light which should get those close to the aircraft scattering quickly as they associate the anti-coll light with impending engine start

Even looking away or down at the ground, the first hint to mechanics or loaders is the noise of the air rushing through the starter.

[rudderrudderrat]

Hi Centaurus,

...all the captain has to do .... is to switch off the aircon pack (s) check there is pneumatic start pressure and motor the engine until someone on the ground tells him the tail pipe fire has blown out.

It used to be a memory item on previous fleets - and it is still not rocket science.

I recall reading somewhere that the internal components of a jet engine can remain hot enough for up to 20 minutes after shut down to ignite residual fuel.

Do you mean hot enough to raise the fuel to above its flash point?
wiki/Flash_point
Not to be confused with "autoignition temperature".

[Dan Winterland]

It's not a big issue as the amount of residual fuel is usually small and it's contained within the jetpipe - which as we know has been designed to withstand temperatures higher than the burning fuel. My company had a review of it's SOPs and it was made a memory item. Airbus said "no need" and the drill went back into the QRH.


What to do if the APU is shut down? Start it. If no APU, then you're going to have to get external air connected - or use a hand held extinguisher. The engine extinguishers are designed to spray extinguishant around the outside of the engine - so they won't be much use.

The 744 required HP air to be connected if the APU was US. The drill was to shut down three engines, connect the air and then shut the running engine down. One day at LHR, a foreign airline did the drill but forgot to do the last item and walked away with an engine still running!

[chimbu warrior]

It's not a big issue

I beg to differ...........It s a known problem on the B737NG (-7 engine) where oil pooling occurs in the tailpipe. The appropriate mix of oil and certain wind conditions have been responsible for several serious incidents.

I think there are other issues that make this potentially a big problem -

• increasing use of ground power at some airports (instead of APU) to reduce noise and/or fuel burn
• reduced manpower by some carriers, meaning that as soon as ground staff chock your aircraft they must move on to other aircraft (crucial time is typically 5 to 10 minutes after shutdown). Another issue here is the propensity for some carriers to require their crew to constantly run from one aircraft to another during brief turnarounds, potentially leaving aircraft unattended during the period of greatest vulnerability
• use of "less skilled" manpower on the ramp by some carriers, and consequent ignorance of what symptoms and signals may mean. This can be crucially important, as differentiating between an engine fire and a tailpipe fire is essential to enable the correct response from the tech crew
• greater use of airports where there are no ARFF facilities, especially by LCC's

Anyone who has seen the video of the China Airlines B738 at Okinawa a few years ago (admittedly not a tailpipe fire) will realise how quickly any fire can get out of control (one flash and you're ash).

[rudderrudderrat]

Hi chimbu warrior,

All that you said seems to be in contrast to this Airbus guidance see page 6
"A tailpipe fire will only occur on ground, during engine start or engine shutdown."

What causes the ignition of your "oil pooling in the jet pipe" 5 to 10 minutes after shutdown?

[tom775257]

I have had a tailpipe fire on shutdown A321 IAEV2500 due to oil pooling. I ran the drill from memory myself. By the time the fire brigade arrived it was all out.

The cause was a faulty oil scavenge pump.

[chimbu warrior]

What causes the ignition of your "oil pooling in the jet pipe" 5 to 10 minutes after shutdown?

Short answer : I don't know, but think it might be the combination of latent heat and a tailwind. The classic B737 (-3 engine) had a problem with tailpipe fires during start.

The CFM-powered A320 (-5 engine) does not seem to have these issues. I have no idea why, but perhaps an engineer could shed light on this.

The Airbus info you provided is very interesting, and would seem to validate some of the points made by various posters to this thread. It suggests that oil will ignite at 260 degrees C, so this would certainly seem possible with a still-hot engine.