You have an electrical fire in the cockpit...
 

As your first action, do you:

- Declare an emergency?
- Turn off the master switch?


My initial instict was to immediately turn off the master. However, I then thought that maybe you want to send a mayday as this is a serious problem, and this may be your only chance to communicate; once the master is off, you don't want to turn it on again...does this warrant a change in "Aviate, Navigate, Communicate"?

I discounted option 3, "Turn off the fuel valve", as just making a bad situation worse.

Aviate, Navigate, Communicate.

Flying the aircraft comes first over anything else. Deal with the problem, sort out your diversion, only then worry about talking.

I'd only cut fuel if it was a fire in the engine compartment. Either way I'd return to terra firma pronto, only worrying about calling Mayday etc. after the circumstances are dealt with.

I wonder how many dead pilots are found in their wreckage still clutching the PTT/hand mic? Sobering thought. :(

Smithy

I think I'd agree with you here, Katamarino. A Mayday call takes a few seconds and this may well be your last chance to communicate.

Master switch OFF
Don't forget to fly the plane
Extinguish the fire if possible, prevent spread
Communicate with handheld radio or telephone

Severity of the problem might dictate an immediate off-airport landing.

I've had a few batteries short out on me but never a fire. Once a flap motor had been cannibalized and replaced with a clapped out one making flap operation five times slower and almost causing a fire. Luckily it hadn't.

If you have a handheld, then you can use that. Alternatively, if you need to stick it in a field/divert to a strip and land no radio, then do that first and then telephone the ATC unit you were speaking to.

Personally, speaking as someone who works with electrickery and electronic gubbery of various sorts, and having experienced electrical fires (thankfully on the test bench, not in the air :uhoh:), including a power supply that blew up almost in my face sending two-foot flames shooting into the air (big capacitors y'see :suspect:), very good idea to kill the power straight away and extinguish the flames. Fire doesn't take long to spread at all.

Prioritise. Deal with the circumstance, then talk.

Communicate what? The position where they can pick up your charred remains? What does "mayday" mean: "help me" in french. No one can help you when you have a fire in the cockpit except maybe your fire extinguisher. Talking to someone far away on the ground is really a waste of time when every second counts.

Would your answer differ in any way if you were in a Cessna with electric flaps?

Talking to someone on the ground who could roll the fire trucks for your return, or come and collect you after you've crawled away from the field landing with a broken leg and burns, could be very valuable indeed.

I cant think of an emergency where the priority would not be deal with the emergency first and only when things are stable deal with letting the rest of the world know. I think most of us feel a mayday somehow makes everything comfortable but in reality there is very little those on the ground can do for us in most emergency situations.

Why turn off the master switch????

Aviate, Navigate, Communicate.

If you have them, don oxy mask and smoke goggles, then determine which system is on fire by isolating systems using the circuit breakers, I am assuming you are flying a light aircraft so there shouldn't be to many systems that would cause an electrical fire, if the aircraft is larger with more complex electrical systems then follow the initial memory items if any, then the checklist.

For example the type I operate has a 6 page checklist for this senario that eventually turns off all electrical systems except for standby instruments then re-instates systems to determine what is causing the fire.

Of course the senario out come is also determined by where you are at the time of the fire, over a remote area or nearby airports etc etc.

This is an interesting discussion, and I wish we had more of this sort of thing on PPRuNE.

Katamarino - good point about summoning help e.g. AFS, rescue etc., there again I would argue for Fuji's point that fire appliances etc. are not much use in the air. Letting someone know where you are is a good idea, however it is a question of priorities.

If there's a funny burning smell or slames start to lick up around the instrument panel any RT would be the last thing on my mind. My own priority would be to fly the aircraft, bring the situation under control and then get on the ground ASAP. Most likely one would be forced to divert into a field, or if the fire had been brought under control, the closest airfield, if it isn't too far away (i.e. a few minutes flight time). If there's been a fire you don't know what sort of damage may hav been done and so I'd want down ASAP. Plus I'd leave all electrics off just in case of re-ignition.

If flying an aircraft with electrically-operated flaps, I would argue it's still not a major issue. Most light aircraft will quite happily land flapless without a huge loss in landing performance. Larger, faster, more complex types perhaps but not C172s etc. A flapless C172 will still get into a field without flaps. If landing distance is really an issue then I'm sure that whacking into a hedge/fence fairly gently at the end of a forced landing is much more surviveable and hence desireable than being burnt to a crisp in mid-air whilst farting about trying to get the flaps down.

I remember an incident with a Cessna in Scotland a few years back - 2007 perhaps? The 60A CB for the alternator tripped, it was then reset and because of a short-circuit it welded the CB closed and caused a fire. They ended up doing a forced landing and everything was OK... anyone have the report for it?

'No one can help you when you have a fire in the cockpit except maybe your fire extinguisher.'

...and you will probably die from the extinguisher fumes if you do use an extinguisher whilst in flight in most small light aircraft!

A number of years ago I was flying as a FO on a Citation out of Biggin.
We departed at night en route to Majorca and passing FL240 in the climb working London I noticed a shimmer around the Captains head which made me think my eyesight had gone funny.
I could then smell burning.
The smoke got worse and became very acrid and dense. We went through the normal procedures for smoke and London Control were brilliant giving us an emergency descent and vectors straight down through Gatwick in a direct line to Biggin.
We had by then evacuated the smoke which was now diminishing and landed at Biggin to be met by the Fire engines who removed the petrified passengers who all though they were going to die.
That smoke was so acrid it ruined all my pilot clothes which reeked.
It is a horrible experience and the passengers could not believe how laid back and casual I was about the whole thing (Show for their benefit :E
Obviously in a piston single if you have an oxygen mask put it on a cheap pair of swimming Goggles will keep eye watering smoke from your eyes.
If not open the side window which will help to remove smoke as well as giving you access to fresh air. Even think of carrying a short piece of tube you can breathe through?
Yes if you suspect an electrical fault switch off the electrics then switch off all the avionics bar one radio. Switch back on to make a call and appraise the situation.
If the smoke continues to build with the master on and one radio go sans radio but ATC can be of help if for no other reason than giving you vectors.
How else will you navigate with maybe diminished visibility and all the electrics off?
But usually get on the ground as quick as possible and ATC can help there!
BTW in our case it was a fan motor in the ducting system.

Pace

MAINTAIN CONTROL
masters off
vents and windows closed
discharge extinguisher ( ur fu*ked if its the old 'fire axe' on board)
when fire is out ventilate cockpit

Now its time to decide
Forced laning in a paddock or strip near by
If tracking to an airfeild make standard overhead or published joining procedure
Make phone calls when you are on the deck

Unless you have burnt through the mag switch wires the engine will still run the wings will still be flying and your eyes can still see.

other than the brown smear in your pants its like loosing your alt and running out of battery juice.

“Unless you have burnt through the mag switch wires the engine will still run”

It will run just as well if they are burnt through!:ugh:

Rod1

Was just thinking the mags fail to live if the wires are cut/destroyed. Flying an aircraft with a smoke filled cabin is probably a bit more stressful than an alt+batt failure too!

I think smoke/fire anywhere *inside* the aircraft is probably the worst emergency you'll ever have to deal with. I'd agree that the first thing to do with an obviously electrical one in a light aircraft is to turn everything off, removing the initial heat source, at least.

My thoughts then would be for an immediate forced landing/ditching, unless it was obvious the fire was completely out. You have so little time to do anything if the fire re-ignites or spreads out of view. Unless an airport was literally a minute or two away, it'd be field/road/lake/river, etc. Without 100% O2 you can be overcome in seconds - even then, you may not be able to see enough to do much other than crash.

As far as using the radio - well, that might be the source of the fire! Hopefully, someone might see you land and ring in with "I've just seen an aircraft go down in flames!" and be right for once...

Not a nice place to be.

This is something that should be aircraft specific. Consider a C152 with vents up high. Closing them only makes sure that you are going to breathe what's already in the cabin. In the case of an electrical fire it will be smoke which will then start to build up in the cabin. Why not open the vents and windows/ doors to get air flow through the cabin? Fire needs oxygen yes but it will surely get sufficient oxygen from the air flow through the cowl? I thought the point of turning ventilation off was to prevent smoke being recirculated to other parts of the aircraft cabin? This doesn't really apply to light aircraft. Hot or mixer air vents would be worth closing.

Would anybody consider turning the avionics switch off first to see if the smoke started to clear? Might be worth considering if you have electric flaps/ gear or what not and you do it as soon as you first smell or see any sign of smoke.

Structured load shedding
 

Electrical fires don't just start burning instantly, usually there is some warning from malfunctioning equipment so turning off this equipment and tripping the circuit breakers may well stop the problem.

If it is clear that the that the supply part of the system is part of the problem then first turn off the alternator before turning off the battery master switch.

In the UK a very quick Mayday call and a thirty seconds or so of 7700 on the transponder will get you no end of help, D&D will tell all the local airfields about the problem and then if your primary trace on the radar heads their way and you try and land you will get a green light from the tower along with all the fire trucks you will ever need if you head for a military airfield, all without you having to talk to them on the radio that you have turned off.

So going back to basics you need three things for a fire.........Fuel, oxygen & heat, if you remove any of these the fire will go out.

The aim should be to remove the heat first by turning off the electrical supply, once ths has been done it is likely the fire will start to subside as most of the contents of the aircraft are fire resistant and won't support combustion alone.

The most effective fire exigushing agent is BCF or HALON as the gas cools, displaces the oxygen and has a chemical reaction with the fire it's self so a quick burst of BFF/ Halon in the direction of the fire will have great effect but be sure to ventilate the area quickly as the reactond between the gas and the fire produces a toxic gas.

So the actions that I would recomend would be:- try to isolated the faulty equipment, if this is not done quickly turn towards a suitable landing place, make a Mayday call and set 7700 on the transponder, turn off the alternator, if no improvement . turn off the battery master switch, land at the nearest place that is safe to do so remembering that you may not have flaps (CESSNA) and may not have stall warning.

I would open all external-air vents, get a quick radio call in, maybe drop the landing gear and Flap 1, and then turn off power.

I always fly with a handheld GPS and a handheld radio anyway.

In a modern cockpit, there isn't much that can burn well in an electrical fire. Most likely you might get a short setting fire to some wiring.

What might burn quite fiercely is a LIPO battery in some handheld device. I carry one of those LIPO protector bags sold in model aeroplane shops, which are supposed to contain the flames (if not the smoke).

For the PA28 (and perhaps similar types)

Are you talking about putting items such as laptops into the LiPo bag from the beginning to the end of the flight, Peter?

That would make sense to me, but from my experience of LiPo fires, once they're started you're probably not going to be able to get anywhere near the device safely, or pick it up.

If you could, I would have thought that throwing the thing out of the door would be both the easier and safer option, at least if you were over a reasonably rural part of the UK. Over central London or a tinder-dry forest there may be other considerations.

Discorde
 

Not a very good fire drill ! A panic turning off of the master switch before any investigation has taken place followed by the discharge of the extinguisher.

Oh , and then turn the whole lot back on for the distress call and to restart the fire !..........I hope the extinguisher is big enough to put out the fire twice?


Who publishes this stuff ?

abgd

If I had a laptop actually on fire, the plan would be

- engage autopilot for altitude hold (AP ALT)
- close the throttle
- rudder trim fully right
- at onset of stall buffet open door and chuck laptop out
- recover as normal

Otherwise try to remove the (hopefully only smoking at that stage) battery and put it in the fireproof bag.

Folks,

Some good info and advice here...

Flight Training: Aircraft Fires

Cheers,

Squawk.

I've had a LiPo flameball in the relative safety of my own home, and all I managed to do was to get out of the kitchen. I might have dared fling it out of the window if I'd been wearing Nomex but it all happened pretty fast. This video is pretty reminiscent of what I experienced. You get a puff of smoke, accompanied by the sound of venting gas, then the chain reaction starts very quickly:

I don't disagree with any of this, but the fact is that airlines do allow laptops to be used during flight, and one assumes they have done some sort of risk analysis, and most laptops have LIPO batteries.

I suspect that the risk of this is very low with any normal consumer product. Model plane batteries have been known to go incandescent more often but I think that is for a number of reasons

- they are charged at very high rates (a lot more than 1C in some cases)
- they are discharged at huge rates - 100A is not unusual
- they get a lot of physical hammering - when a model crashes, it could be 100s of Gs, and I know that often the battery is totally smashed, but if it is still "apparently" working the owner is not going to chuck it away because it probably cost £100
- I don't get the impression that model plane bits are of particularly good quality - they are constantly packing up...

To minimise the risk, I also tend to not charge batteries during flight. I tend to keep the device(s) charged so even though the supply is connected, the internal charger turns off ASAP.

In the PA28, switching off the master switch would not immediately compromise aircraft controllability or safety. In instrument conditions suction gyros would remain functional and pilots flying at night would most likely carry a torch for standby illumination of the panel. If the system causing the problem can be isolated then the option of switching the master switch back on is restored.

As in all emergency situations, there will be judgement calls to be made following risk assessment. For example, is the fire severe enough to warrant discharge of the extinguisher, which will bring visibility and breathing problems (as will the combustion products of a fire which is not extinguished). The benefit of a distress call is that the emergency services will be alerted. You may well need them later, particularly if your landing is away from an airfield.

A final point is that checklists can never replace sound judgement. They are designed to assist you in dealing with most normal and non-normal situations. Occasions may arise where you need to deviate from published checklist procedures because circumstances demand it.

Further to a point mentioned a couple of times already in this thread, discharging a fire extinguisher on board an aircraft.
Obviously if a fire occurs, one of the things a person might do is to set off an extinguisher, but if it a powder-type device, and especially if it is a non-controllable (i.e. a one-shot empties all at once) and especially in an enclosed light aircraft (PA28, 152, 172, etc.) the chances are that you will almost immediately become incapacitated by the powder. It smothers everything, people included, and is harmful to inhale.
I am not 'up' on rules and regs. regarding fire extinguishers on board light aircraft, perhaps powder types are discouraged, or even banned, I don't know. But I have seen them in situ in various light aircraft I have seen fairly recently.

I had a short circuit in a Truimph TR7 car, a few wisps of grey smoke form behind the dashboard. I jumped out, grabbed a spanner i had in the boot and disconnected the battery. All that took was about 5-7 seconds.
The cabin by that time was filled with a grey acrid smoke, one whiff of which i caught as i opened the door took my breath away. If i where in that cabin i would be dead within a few seconds.

I had a Cessna ldg light switch short out, known for doing that, again a few wisps of cigarette type smoke, i gave very quick call to ATC and switched off the master switch and landed asap.
I wouldn't trust an aircraft fire extinguisher, used a dry powder twice to put fires out, useless. Just watch those motor racing crash videos.

I have to ask. Does anybody actually look at the emergency procedures in their POH? All Piper and Cessna POH's have a section in the emergency procedures manual that deals with cabin fires and all these procedures start with turning the master off.

To those who advocate other courses of action I am curious to know what makes you think you know better then the factory engineering test pilots that wrote the emergency procedures?

I would also add that both manufacturers and regulators have rethought the circuit breaker resetting procedures. The now virtually universal consensus is to never reset a circuit breaker unless the emergency checklist specifically calls for it and to never reset a circuit breaker twice.

For light aircraft I teach to never reset a circuit breaker in flight unless the electrical service it is protecting is essential for continued safe flight.

There are a few different types of LiPo batteries, and my impression is that some of the newer ones are much less likely to spontaneously combust than older ones - even with the trials of r/c use. I recently tried puncturing the battery from a dead PicoZ type helicopter (cheap £10 micro-helicopter) and... Nothing happened. I also had a small 850 mAh 3s battery where one cell died and the others got way overcharged. I disposed of it safely in a glass of salty water, but was pleasantly surprised that it hadn't already blown up - a few years back there would probably have been fireworks.

I'm not sure quite how popular LiPo batteries are in laptops - a while since I looked into them and at that time Lithium Ion types or LiFe were more popular and these are much more difficult to provoke.

Although LiPo fires are quite fierce, they are brief and probably don't release much more energy than an exploding cigarette-lighter - even for quite a large battery. I wouldn't be surprised if it were possible to deal with one burning up in the passenger compartment, but the cockpit (as in a light aircraft) might be another matter.

On the other hand, an UPS air-freighter may have been brought down by a LiPo fire in the hold, and MIT were recently fined for failing to label a packet of Lithium batteries that were sent by air-freight.

The other thing to watch out for is temperature changes. The voltage the batteries produce varies with temperature, but the critical voltage at which they spontaneously combust stays relatively constant, so if you charge them in the cold then bring them inside, this can send them off. At least two people have come to grief recently from the helifreak forum. One person lost his SUV a year or two back, and another lost his house. Thankfully his family and pug dog survived.

My helicopters mostly run on A123 batteries - LiPo are fine if you've got a garage with a concrete floor, or a detached shed. But when I lived in a flat they gave me the heebie-jeebies.

The POH does indeed specify Master Off as the first action. It would be naiive to unquestioningly assume this is the best course of action in every imaginable scenario.

POH checklists tend to be a bit lacking in general, and no one uses the emergency one's during an emergency. It's much more likely most pilots will use a generic memory checklist.

It would be silly to assume the aircraft manufacturer checklists are the be-all and end-all and I say that because if you look at a POH and then look at, for example, the engine manufacturers manual they often are somewhat different about engine handling. So who knows best? The aircraft manufacturer or the engine manufacturer?

Timeline: Swissair 111 crash investigation - Canada - CBC News

There was a very good film made of the Swissair MD11 crash where the Captain was an official procedures man! The First officer made all the right judgments but the Captain insisted on going by the book and left the final approach to go out to sea to dump fuel with awful consequences.
Every situation is different but priority with smoke in the cockpit has to be to land as quickly as possible.
As stated I have been on a flight with an electrical fire and until you have experienced just how dense and acrid the smoke can be it is hard to appreciate the reality of such a situation.
In a light GA first port of call has to be to isolate the source of the fire so the master switch has to be the first point of call in an electrical fire.
I would probably then manually shut everything down apart from one radio and then go back on with the master and monitor the situation.
ATC were a massive help in our night fire basically because they reduced the work load by giving us direct vectors and clearing airspace for an uninterupted descent so if its possible to keep radio contact all the better even if the radio is on for short periods of time.

Pace

I've posted the link to the film below.

Thanks for the link its a must watch as it highlights a number of points.
One in this instance is that every situation is different and while going by the book is correct in most circumstances there are times when you should chuck that away and go with your instincts.
The first officer was sensing the right decisions the Captain was a by the book man but whatever a sad result!

Pace

Exactly. I may add that in the UK you'll never land far from someone (some remote parts of Scotland excepted), but if you fly in places without human presence, letting ATC know what's up is, IHMO a very good idea. You don't even have to travel very far for that, parts of central France or Spain are pretty empty.

If possible, I would therefore do a quick Mayday, hit the squawk ident button and then shut everything off PDQ.

I completely disagree with this statement. All the typical later model aircraft you will find at flight schools and clubs have a pretty comprehensive set of procedures for the likely emergencies and they all specifically cover the cabin fire emergency.

The outfit where I do some part time instructing flies C 172P's. The POH for this aircraft has emergency procedures which follow the industry convention of showing those items which are meant to be done by memory in bold face type and the remainder in plain type. I require my students to know all of the bold items by memory and quiz them regularly to insure they know them. There are not a lot of procedures to memorize so I do not consider this an onerous task.

When the bad thing happens and the pressure is on, this is not the time to start making things up, you have to have the initial procedures down cold. The POH emergency procedures are not perfect and will not fit every problem but I firmly believe every emergency should start with the publish procedure and deviations from it should only occur when its actions are not making the situation better.

The bottom line is a cabin fire in a light aircraft is IMO the worst possible emergency. They are almost invariably caused by electrical problems and removing power ASAP is vital to limit the progression of smoke/flames. I would also add that at the accident record suggests that the majority of the accidents caused by electrically induced cabin fires where in aircraft with known or knowable preexisting electrical problems.

My person belief is that flight schools do place sufficient emphasis on the potential dangers of misbehaving electrical services. I am also surprised and disappointed with what seems to be a widespread UK attitude in UK light aviation towards the POH. It seems to me that the POH of a UK aircraft generally sits on some shelf still in its original wrapper and instead aircraft are operated on a series of locally made up procedures. The POH, especially the ones for later model Cessna's and Pipers has a wealth of valuable operating data and IMO should be well read and understood by every pilot.

Big Pistons
 

I don't think that the Piper or Cessna test pilots are the only input to the POH, I would guess that the company lawyers have quite a bit to say on the subject and most of what lawyers say is about protection for the client, not for the protection of the pilot.

A quick assessment of the situation is far better that rushing blindly into a situation that you could have prevented by a small amount of thought. I don't advocate keeping the electrics running for more that about 60 seconds, 30 seconds of thinking and trouble shooting and 30 seconds for the mayday call & 7700 on the transponder. At no time did I say reset any circuit breakers, I said TRIPP the CB's of suspect system, after all it could be a problem with the CB it's self.

Big end bob the electrical cable fitted to aircraft should be of a much higher quality than that fitted to cars and one of the requirements is for the cable not to support combustion, I doubt if an aircraft would catch fire in such a dramatic way as your car unless you did nothing about the problems that were becoming evident. The higher quality construction of aircraft electrical systems won't prevent a fire but it will give you more time to do something about it.