Offshore Fire Warning

[the coyote]

You are in this scenario:

In a twin, offshore and the closest possible landing site is about 45 minutes away. You get an engine fire warning. There is no smell or smoke or other spurious engine indications.

Our checklist says confirm the fire then shut then engine down and activate the extinguishers in turn. If both fail then land immediately, which would involve a ditching.

The last 3 fire warnings I know of resulted from electrical malfunctions.

How do you define "confirming the fire" and what would you do in this situation, if all you had was the warning?

[fflyboy101]

I have heard that tha S61 (I think) or the super puma has a rear view mirror and the PIC can also ask crew members to check. I am sure there are others that can answer better than me!

[MOSTAFA]

Have you just flown through a shower? Older systems with firewire can sometimes get a drop of water that does not drip off and tends to evaporate. Sadly during the evaporation it tends to boil (hot engine) and can give you a spurious caption. Anyway, back to SSE and look for signs, normal guage scan and the odd turns to look over your shoulder for smoke. Positive signs, close it down. No positive signs, GI the the engine, now the dodgy bit!! caption remains, close it down and recover. Captions clears, leave it at GI and monitor, might!! use it for landing, depends on loads of factors, captaincy decision! all sorts of reasons, hot gas leak etc. Works for me

[NickLappos]

the coyote,

Some RFM's are specific, as example the S-76 calls for smoke, erratic engine indications or erratic engine behavior (that is from memory, but I wrote that paragraph so I hope it is close). Even if they dont say that, use your judgement.

If a single (albeit reliable) system such as the fire indicating system had the power to make you automatically ditch, the idea of Catagory A would be defeated, wouldn't it?

One very important observation that your question triggers is that the pilot's judgement is supreme, and worthy, in the face of little lights that scream at you to do something. If we truly trusted each individual light and gage, we'd just wire them to the sticks and leave you home!

One romantic version of this philosophy is shown in "The High and The Mighty" where Ernest Gann puts his pilots into such a situation, and tells us that judgement and airmanship cannot be dictated by blinking lights.

In the situation where an engine fire light/tone came on, I would look for INDEPENDANTLY dervived confirming indications, that is, something else telling me at least a hint that the light/tone were right. In the absence of confirmation, I would abort and place my aircraft and pax on a safe path, in case I was wrong.

Confirming indications will be there (think of all those indicator harnesses hanging in the fire zone - one of them will bake and tell you something!). On FAA aircraft (not military ones generally) the indicators are all independant, so they have separate wires, power and processing. One indication could be a flaky electron, two or more is the real thing, kimo sabe.

Even in the real thing, you have some time if your boss bought you a good helicopter. In a Part 29 transport twin, the fire zone must hold full integrity for 15 minutes in a rageing fire at 2000 degrees F. There are not 15 minutes of fuel in the fire zone. If you get the fuel firewall valve closed, the fire will burn itself out in most cases, even if the extinguisher fails (and the extinguisher has dual independant systems, with dual bottles, dual squibs on the bottles, dual plumbing and even dual double throw switches in the cockpit.)

If there is a real fire, and you can't get it out on a transport helo, it is really not your day!

What to do with a fire light/tone? Here are some examples:
1) No confirmation - get ready, start goint to the safest place, divert if necessary to do so. Don't shut down the engine, but beedy eye those other indicators and be ready.
2) Confirmation, like a few swinging gages, and maybe an erratic engine - slow to OEI speed and set yourself up. Bring the affected engine back to idle. CONFIRM that is the bad engine - both of you- and then think real hard, and confirm again. Some test pilots think the engine levers should be in the baggage compartment, bcause this step is so important, and so often screwed up. Do not be in a hurry, you have the rest of your life to live with the decision, and too slow is only a problem in tail rotor failures and sudden dual engine stoppage. More twins go down because the crews shut down the remaining healthy engine than for the cause they were trying to fix!!! Fly to the safest place now, OEI, and give up a foot of altitude as if it were a pint of blood. Tell everybody you know what is going on, and never fly over a safe landing place to get to a safer one! Your maintenance chief will hate you, but he does, anyway!

Ditch almost never. If it can fly, fly it. If the problem is quite serious, and handling/vibrations are really a mess, then think about ditching, but if it is -10C and sea state 4, get low, get ready to ditch and keep flying. If it is +30C and balmy, get your calls off, get everybody ready, and go for a swim.

Here is a training flick that Sasless and I prepared. It shows CRM at its finest:

http://www.s-92heliport.com/highmighty.wmv

[sycamore]

A couple of things to add would be to shut off anti-ice, if possible, if in use, and cabin heating. Try also to "skyline" your previous track, to check for a dark trail, or if you have a strong shadow ie above cloud , it may give you confirmation..., or not. Turn off all non-essential electrics, as every little helps.
Another airmanship point would be to have your Crit.Points for both engines, and s/e ,worked out so the decision to continue or return should be clear...

[Bravo 99 (AJB)]

Nick you post is extremely interesting and thanks.

but I have tried to get to you clip but it wont come up, any ideas

Sincerely

Andy

Bravo 99 (AJB)

[SASless]

Sounds like you work for the same outfit I did....various attitudes towards "slavish" adherence to the checklist.....some of the boss fellahs...and training captains would have you doing just as the checklist said.....

For example...Bell 212 checklist for an engine chip....it was specified by checklist to climb to a safe altitude and shutdown the engine.....or if you got a Gen Hot light.....same thing....blindly shutdown the engine....

I agree with Nick....use your best judgement...do that which puts you least at risk....and definitely....if you fly, one must be a reader of Gann. If you fly and do not know Gann....you are not a true aviator.

[NickLappos]

Sasless,
I even wrote those words at the front of the Emergency Procedures section of the S-76A flight manual that said that multiple energencies or unusual conditions could require the pilot to deviate from the published procedure - specifically to help the aviator who made it back to be able to justify what he or she did.

[helmet fire]

Intresting thoughts.

Personnally, I like the bit where Nick says to make your own judgement whithin the confines of checklists, etc. I think that as long as you can justify your decision as reasonable, you are good to go. I like to apply a risk management type solution where time allows and indications are questionable - exactly as SASless says - choose the assesed lowest risk option.

For example: in the offshore scenario mentioned by coyote, if the weather was fine and beaut, I was at sufficient altitude (or could climb there) and the landing area was a nice big fat runway, then I would try the diagnostics that sycamore suggests, and probably shutdown the donk. The chances of a secong donk failure are so minimal (and you should be at altidude that would allow engine relight) and an OEI landing to a runway should present minimal risk in comparison to the look on your face if there really was a fire and it did not give you secondaries until too late. BUT, if I was over tiger country, low level, in cloud at night, p1ssing pickhandles etc etc, then NO WAY would I touch that lever without secondaries.

In the example SASless gives and unlike SASless, I would, and have, climbed to sufficient height, and shutdown the engine in a 212 following an engine chip light with no secondaries. I diverted back to the airfield about 10 to 15 mins away, and as I had no secondaries prior to shutdown, and I was very heavy, I restarted the engine on long finals, and gently opened the throttle looking for secondaries to appear. I then committed to a running landing below OEI powers knowing that I could use both donks if I stuffed it up. In a BK117, in similar circumstances, I also shutdown a donk, but was really light and could hover OEI, so I didnt restart the donk. Risk management.

So are the chance multiplied by consequence of a second, sudden engine failure higher or lower than the chance times consequence of not following the checklist after a fire/chip light? That's what we get paid for, and everyone will have a different assessment of the answer, thus my original statement that you have to be able to justify your decision - particularly when you elect not to follow the checklist.

[Steve76]

Far be it from me to be the devils advocate.....or side with the pedantic individuals in management.

But in this occurance I think that the correct response is to follow the checklist to the letter.

I have learned that it is easier to defend your actions with a foundation of decision making based on the gospel of the SOP'S. Later on, there is very little that they can do to **** you, if you follow them to the detail. Especially the company Coyote works for.

They are not wanting you to make commonsence decisions in the two crew environment anymore. They want you to leave your experience and analytical skills back in the crewroom.

I'll wager that if you returned to the base with the fire warnings illuminated, thinking you had just saved two bottles and an aircraft from ditching that you would be held high. WRONG. That is BS.

They will fire or chastise you for not following the rules because the rules are very clear.

ME: I would ditch. Easy to defend. I have the little black book of commonsence from the wally's to tell me and the world that I acted with their blessing.

Unfortunately Nick, your words and intentions needed to be more explicit. Your assumption that everybody out there might be reasonable in dealing with these issues, was flawed.

I guess the world was a far different place in 76.

[the coyote]

Thanks all for the responses, keep them coming.

Nick, your info especially re the fire rating stuff is much appreciated. And the video was a good laugh!

Thats pretty much what we were wondering, if you decide to head on for land for 45 minutes with a light on, and there does happen to be a fire back there, is there any risk it could find its way to more than 15 minutes of fuel beneath the boot?

Flogging along with the light on also does leave plenty of time to wondering about covering ones ass at the other end, regardless of the outcome...

As any cojoe knows, there are Captains that blindly follow the checklist, there are others that almost couldn't tell you where it is located, and there are others that don't have a lot of capacity for common sense in a grey area scenario!

If anyone has had a genuine fire in flight, did it give you good solid secondary inidications, ie smoke and other systems failures?

I don't want to get to the point where next time the warning comes, my first thought is to presume electrical problem if you know what I mean.

Thanks all for your input, PPrune can be a handy resource as well as interesting reading!

[imabell]

the video reminds me a lot of student training techniques.

i'm flying on nick's aircraft, if it flies keep flying it.

deep water, sharks, cold, miles out, not this little black duck.

:{ :{

[VTA]

Steve 76 has a good point there. As a company training pilot, part of my job to ensure the company emergency check list is followed at all times. The emergency check list is there to keep an average pilot out of trouble within the confines of approved company procedures. However, I would certainly look long at hard for secondary indications of a fire before shutting it down and encourage all to do like wise. Look for smoke by turning in the direction of the fire, fly out of balance a bit (at reduced speed), is there a smoke shadow over land etc etc. You don't always need a mirror. Like Nick said, one of the most important things is "DON'T RUSH!!!"

[Nigel Osborn]

Having had numerous fire warnings over the years, the only real fire I had gave no warning. The chief engineer in Mt Hagen, PNG asked me to do a ground run after an overhauled C18 engine had been fitted to a FH1100.
The start went normally and the first surprise was when the engineer opened my door and took the fire extinguisher! This drew my attention to a possible problem. Even more so when he opened my door again and said switch off and start running! The C18 had an internal fire with flames coming out of the exhaust and hence it could not be picked up by any engine bay detectors. The strange thing was the T & Ps were all normal and if he hadn't been there, I would have expected all to be normal.
All the points raised about checking for a real fire make sense, especially if you are miles over the sea. I had a BO105 give a fire warning while air taxying at Aberdeen. I immediately landed, shut down and got the pax to move out. There was no fire but totally unconnected with that problem, I had a massive fuel leak which would have caused unpleasant problems after take off.
So I believe if you can, land & check; if you can't land, make whatever checks you can including opening windows or doors and sticking your or someone else's head out!:O

[B Sousa]

As usual Nick has a very good piece on the subject. One that I believe to be best at least from someone who has single engine time across the Caribbean is "if it flys, fly it" but be prepared for a swim. Ditching many miles out into Jaws land is not always the best idea, if it can be prevented. Sort of like a Main Rotor Transmission light, get ready and as long as it flys, the shorter the swim.
On the same note, I just read an article in World Airnews June 2004 www.airnews.co.za It was regarding the fatal accident of Swissair flight 111 in 1998. Article is entitled "Procedures or Survival." Basically it was that the crew followed procedures to the letter when the copilot had wanted to deviate to eliminate things rapidly. Its a good read on the subject.

[Attila]

My 2 pennorth for what it is worth.

I have had an engine fire in a B212 which resulted in a ditching. This one had treble indications, a bang from the back, an engine chip warning plus a high ITT, followed by the fire warning. Two shots of the bottle, still indicating a fire, so I ditched. No worries.

I have also suffered engine chip warnings, and shut down an engine, only to relight it for landing.

The generator overheat referred to by SASless indicated, I think, a potential breakup in the generator itself, hence the reason to secure the engine.

The S61 does indeed have a rear view mirror, and I have had spurious warnings. The initial part of the drill calls for the speed select of the affected engine is retarded. This checks for a split combustion chamber, as the fire warning will gradually diminish if the chamber is split, but remain illuminated if either genuine or spurious. You then check for secondary indications.

However, consider this actual scenario, which occurred about 18 months ago to an S61 SAR aircraft operating at low level just off the south coast of UK.

Engine fire, confirmed by warning light and smoke, followed by a loss of one hydraulic system, followed by a main gearbox loss of pressure warning. The crew made land, a couple of miles away, landed and got away safely. The aircraft was a totally burned out. Time from start to finish was 80 SECONDS!! I have done this in the simulator in 90 seconds and I knew what was going to happen.

[The Nr Fairy]

The link for the accident report Attila hunts (sorry, it's weak, but it IS 5 am) is here (http://www.dft.gov.uk/stellent/groups/dft_control/documents/contentservertemplate/dft_index.hcst?n=10078&l=4).

[NickLappos]

Great link, typically very thorough report.

Note that this event was really not a fire, it was an engine bearing failure, followed by a split engine and broken engine mount, followed by engine misalignment, shaft rubbing, and a transmission case fire. The fire warning sounded because the engine split and combustion products spewed into the fire zone, where they lit the fire warning light.

The subsequent failures of transmission oil and servo systems were new and drastic emergencies in the sequence, certainly justifying the ditch/immediate landing. Great job by the crew, well handled, IMHO.

Nice advert for HUMS, too, with all that great data to help diagnose, and prevent the next one!

[Attila]

First of all, let me apologise for the abrupt manner in which my last post terminated. I had intended to say a little more. Laptop battery failure, followed by an total mains failure!

Nr Fairy, thank you for finding the appropriate link.

NIck, you are right in your precis of the report. Another chip dectector is now fitted in the region of the number 5 bearing, with an appropriate change in procedures.

Steve76 and VTA both advocate the use of the checklist, to which I would like to add one rider, "Fly the aircraft". The use of the checklist is called standardisation. In a two-crew environment in particular, each crew member needs to know that the other will react to an emergency in a standard manner, and not confuse the issue with any surprise decisions. At the end of the day, though, as in this emergency with the SAR S61, the captain has the overriding authority to make such decisions as he sees fit.

I note that this is my 12th post in about 5 years, so I'll quit now, as I don't wish to be accused of being too verbose.

[NickLappos]

Bless you Attila, for saying it so well, "At the end of the day, though, as in this emergency with the SAR S61, the captain has the overriding authority to make such decisions as he sees fit."

This is not carte blanc to do whatever, but it reminds us that the checklist is an informed guideline, not a set of handcuffs. Picture captain Jean-Luc saying, "Romulan Battle Cruiser at 2.5 parsecs? get out the Romulan Battle Cruiser check list!"

[VTA]

Ah Yes Nick,

What we see here is Jean Luc using his "Immediate Actions" for Romulan Battle Cruiser within 10 parsecs....During the commercial break, Number 1 will be told to get the checklist out and go through the "Subsequent Actions". But we never get to see that!!!:E

[Collective Bias]

Great thread, need to get it going again.

In the Flight Manuals I have come across, I have never seen a specified time peroid before you use the second fire extinguisher bottle.

I tried to get an answer from Sikorsky once about getting a recommendation for the system that is in the S76, but they declined.

The emergency checklist in the S76 says "If fire persists - use reserve bottle".

What is that 10 sec? 30 sec? long seconds anyway.

It varies depending on many factors I'll guess, type of detector, size of engine bay, manufacturer????

Anybody have a suggestion, or experience I'd be glad.

[NickLappos]

collective bias,

How to measure persistence? The fire supressant only creates a fire snuffing environment for a few seconds. If the fuel and ignition source are still available at the end when the gas is scavenged out by the normal airflow thru the compartment, the fire will reignite. That is why you shut off the firewall valves and shut down the engine first.

If the first bottle doesn't work almost immediately (several seconds?) then ready the second bottle. Recall that you have minutes even if the fire is raging (great theory, right? Imagine at night, overwater, how long 10 seconds of a screaming fire light seems!)

Exactly how long to wait? It is impossible to script all the possible fire scenarios, thus you can't really expect a procedure. Theoretically, the first fire can't happen. Theoretically, the shutoff of fuel/oil and engine should be enough. Theoretically, the first bottle should be enough. Now ask for precisely how long to wait for the second bottle.

Not too long.

[Collective Bias]

Nick

Good comments.

Not really an answer though, I'll quess that's because there is no absolute answer. If I read you right you should use the second bottle in about ten seconds - thats fair, given the quick reaction of the S76 detectors. The scoop on the side of the engine cowling most also do it's best to blow away all the extinguishing agent rather quickly.

Speaking of the scoops.

Why was the Arriel engine cowling scoops air direction changed from the Allison, to get better function of the extinguisher? or just because of a diffrent heat source?

[offshoreigor]

WOW!

What a great thread! Everyone is using common sense balanced against the check-list.

I never had any problem with what my course of action would be on the 61 or 212 because it was a No Brainer. If the light came on immediately, it was 99.9% for sure that it was a false indication. If it started to glow dimly then get brighter, it was the full meal deal!

The 76 is a different animal. Because it uses IR instead of heat, it will only come on immediatly not slowly so even if you are having a bad electron day and the system is just giving you a false indication, unless you are VMC where you can possibly visually confirm or rule out a fire, you are committed to the Check List. Which means, OEI and a healthy dose of that Tri-Bromo whatever crap in the bottles going into the atmosphere! Nasty stuff!

Cheers, :eek: OffshoreIgor :eek:

[maxtork]

Well not that anyone wants the mechanics perspective but...

I say if you can get it home safely and let me fix it ...great, but if you for one second have doubts about it I would rather have to fish the machine out of the drink and bring you home wet and in one chunk then to have you push your luck and get the dreaded phone call about your aircraft going down and no survivors. The pilots and mechanics may pick on each other worse than any brother and sister the world has ever known but we always worry about you guys.

As for common sense that even works on our side of the house. Not all of lifes questions are answered in the almighty maintenance manual. Luckily for us we can make a decision always on the side of saftey and only cost down time and parts.

Fly safe!

[Rotorus]

Collective Bias:

You have two bottles, and you wont be needing the second one later would you? I`ll say use them both....

[Collective Bias]

Rotorus

Yeah, I'll guess you are right on that. It ain't your day anyway, and chanse of having a second fire later on, if you put out the first one good should be very small.

Anybody who has experience:confused: