You have an electrical fire in the cockpit... [Archive]

Captain Smithy

18th Jul 2012, 09:55

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.

what next

18th Jul 2012, 10:14

...this may well be your last chance to communicate.

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.

Jev Flyer

18th Jul 2012, 10:17

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

Katamarino

18th Jul 2012, 10:18

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.

Fuji Abound

18th Jul 2012, 10:19

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.

Above The Clouds

18th Jul 2012, 10:45

Katamarino
As your first action, do you:

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

My initial instict was to immediately turn off
the master.

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.

Captain Smithy

18th Jul 2012, 10:54

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?

Shoestring Flyer

18th Jul 2012, 10:57

'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!

Pace

18th Jul 2012, 11:13

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

Ralis

18th Jul 2012, 11:22

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.

Rod1

18th Jul 2012, 11:30

“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

1800ed

18th Jul 2012, 11:36

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!

FullWings

18th Jul 2012, 12:43

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.

The500man

18th Jul 2012, 13:10

vents and windows closed

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.

A and C

18th Jul 2012, 16:49

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.

peterh337

18th Jul 2012, 17:11

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).

Discorde

18th Jul 2012, 18:29

For the PA28 (http://steemrok.com/PA28EMERGY) (and perhaps similar types)

abgd

18th Jul 2012, 18:49

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.

A and C

18th Jul 2012, 19:11

peterh337

18th Jul 2012, 19:31

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.

Squawk_code

18th Jul 2012, 20:36

Folks,

Some good info and advice here...

Flight Training: Aircraft Fires (http://flighttraining.aopa.org/students/flighttestprep/skills/fire.html)

Cheers,

Squawk.

abgd

18th Jul 2012, 20:42

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:

Overcharging LiPo battery - YouTube

As for LiPos within electrical items... If I learned one thing during my childhood, it was that confining explosions tended to make them better! Either way, you I suspect that in a noisy aircraft it would all be over before it was possible to do anything much about it.

peterh337

18th Jul 2012, 21:46

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.

Discorde

18th Jul 2012, 21:59

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 ?

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.

Noah Zark.

18th Jul 2012, 22:03

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.

BigEndBob

18th Jul 2012, 23:12

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.

Big Pistons Forever

19th Jul 2012, 00:35

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.

abgd

19th Jul 2012, 00:48

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.

Katamarino

19th Jul 2012, 05:53

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.

The500man

19th Jul 2012, 07:34

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?

Pace

19th Jul 2012, 08:21

Timeline: Swissair 111 crash investigation - Canada - CBC News (http://www.cbc.ca/news/canada/story/2011/09/12/f-swissair-crash.html)

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

FlyingLapinou

19th Jul 2012, 08:46

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.

I've posted the link to the film below.

Swissair Flight 111

Pace

19th Jul 2012, 13:51

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

172driver

19th Jul 2012, 14:01

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.

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.

Big Pistons Forever

19th Jul 2012, 14:55

POH checklists tend to be a bit lacking in general, and no one uses the emergency one's during an emergency.

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.

A and C

19th Jul 2012, 15:09

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.

The500man

19th Jul 2012, 15:35

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.BPF, that is true but not everybody has a later model. My S2A POH includes emergency checklists for in flight engine restarts and freezing of the pitot-static head, and that's it. The S2C handling notes I have do include engine/ electrical fire checklists.

Interestingly it suggests if the fire doesn't go out or you need electrical power to continue the flight, switch the master switch back on and then start pulling CB's until it goes out. For an engine fire it suggests using a higher glide speed to find an airspeed which provides an incombustible mixture, then if it doesn't go out and you have a parachute with sufficient height remaining, it suggests you jettison the canopy and leave the aircraft!

Big Pistons Forever

20th Jul 2012, 00:49

BPF, that is true but not everybody has a later model. My S2A POH includes emergency checklists for in flight engine restarts and freezing of the pitot-static head, and that's it. The S2C handling notes I have do include engine/ electrical fire checklists.

Interestingly it suggests if the fire doesn't go out or you need electrical power to continue the flight, switch the master switch back on and then start pulling CB's until it goes out. For an engine fire it suggests using a higher glide speed to find an airspeed which provides an incombustible mixture, then if it doesn't go out and you have a parachute with sufficient height remaining, it suggests you jettison the canopy and leave the aircraft!

I would suggest that the Pitts S2A is not a "typical" training aircraft at your average flight school. However if the point of the post is to point out that all POH's may not contain all of the information that is in the "typical late model Cessna or Piper POH's" ( ie anything built after 1970) that represent probably 95% of the aircraft that the are in a flying schools and clubs; then you are correct. For those aircraft it is up to the pilot to fully understand the systems and develop appropriate procedures. For the other 95 % it would seem reasonable to me to start by knowing and following what the factory POH says rather then just ignoring it and making something up.

Since the Pitts is a Day VFR machine I can't think of any situation where electrical power is essential for continued safe flight. It would seem to me that just turning off the power and landing NORDO at the nearest practicable airport would seem the best course of action. That is of course assuming that the smoke/fire immediately stopped. In any airplane an uncontrolled cabin fire is a desperate emergency and an immediate landing at the nearest survivable surface carried out as quickly as possible is IMO the best course of action.

As for engine fires the good news is every incident/accident report I have ever seen where the engine was immediately shut down and secured at the first positive sign of fire resulted in the fire spontaneously going out. The disasters occurred when an engine which was on fire was for what ever reason, left running.

Big Pistons Forever

20th Jul 2012, 01:11

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.

[

The 3 memory (bold) items in the C 172 checklist for a cabin or electrical fire are:

Master ............. Off
Vents, cabin air...Off
Fire Extinguisher..Activate.

The non memory items call to ventilate the cabin after assuring the fire is out and land ASAP. Personally I don't see a lawyers hand in what to me represent a pretty practical set of actions.

I think leaving the master on for a whole minute when suspecting a cabin fire is lunacy. 60 seconds is plenty of time for a dead short to heat up to many hundreds of degrees with the heat feeding a fire which can quickly get out of hand. If you flying day VFR in a light GA aircraft which I think applies to the majority of people reading this form, then again, I can't think of any circumstance where electrical power to the cabin is essential for continued safe flight.

Rod1

20th Jul 2012, 08:37

“I can't think of any circumstance where electrical power to the cabin is essential for continued safe flight.”

Flight in 112 could be an example…

Rod1

riverrock83

20th Jul 2012, 09:15

“I can't think of any circumstance where electrical power to the cabin is essential for continued safe flight.”

Flight in 112 could be an example…

Rod1

Well if you have an electrical failure then "help" is going to be with you so much more quickly there...:}

172driver

20th Jul 2012, 14:10

BPF, I'm as much a stickler for the POH as the next guy, in fact the one of the a/c I mostly fly sits right next to me now.

However, nowhere in a POH have I yet found the phrase:

Brain - switch off

I would switch the master off PDQ also, but especially when flying in remote areas I'd really try to get a Mayday and an 'ident' out first. Obviously, if the flames are already licking at my feet I might not.....

Re the handheld - fuggetaboutit for most situations. Unless you have an external antenna and have it rigged and ready, these things just don't have the range required.

From AOPA Flight Training, referenced somewhere else on this thread:

If we have time to communicate before powering down the electrical system, we have three options. Call ATC, broadcast in the blind on the emergency frequency of 121.5 MHz, or tune the 7700 emergency code into the transponder and IDENT. Taking a few seconds to do any of these things before we shut down the electrical system might alert someone to the problem and bring fire/rescue services to the scene as we head for an airport. Finally, if it has a manual switch, we can activate the emergency locator transmitter. The beauty of the ELT is that it has its own power supply and will bring help to the scene of a forced landing should that become necessary.

Makes sense to me.

A and C

20th Jul 2012, 14:24

Big Pistons Forever

20th Jul 2012, 14:42

It is very hard what qualifies an electrical fire in the early stages, the first unusual smell should get the pilot looking for a problem and mentaly getting into electrical power down mode......... But not an unconsidered electrical shutdown.

A few years ago I had the low volts light come on and the alternator load fall to zero along with a smell of burnt rubber, I was thinking about shutting down the electrical system but with no other indications and all the other electrical equipment functioning I just off loaded all unnecessary electrical equipment and landed normaly....... The reason for the trouble was a broken alternator belt that had come to rest on the cylinders.

It would become very quickly apparent if things were progressing from a minor problem into one that could not be contained unless drastic action was taken, I take the view that you need to be sure that he action you are taking is the correct one for the situation and not a vast over reaction that will put the aircraft in more danger than is necessary.

Of course if you are starting to get acrid smoke, erratic indications etc there is no doubt that the electrical master switch has to go off, what I don't want to see is very low time pilots shutting own electrical systems in blind panic and then making a panic approach with no flaps or stall warning system and getting it all very wrong.............and then the accident investigators find that the inital problem was a system had shorted, there was a slight burning smell, the system CB had tripped to protect the system as it should have and there was no danger of the problem escalating.

The title of this thread is "you have an electrical fire in the cockpit". The original poster asked about dealing with this emergency by first making a radio call. I reiterate my absolute belief that when you think you have a fire, which to me would be a strong burning smell, and/or the presence of any smoke and of course when visible flame is obvious, then you don't waste time talking on the radio you immediately follow the POH fire checklist starting with turning off the master. I do however support the recommendation of an earlier poster to turn on the ELT via the remote switch.

The bottom line is simple. Every emergency should start with fly the aircraft , deal with the emergency, then talk on the radio. Again I am struggling to think of any light aircraft emergency where talking on the radio is going to be the first thing you do.

I guess we will have to agree to disagree on this one.

Finally if landing with no flaps would cause British PPL's to "panic" then the state of your flight training is worst then I thought. Oh and single engine Cessna's do not require power for the stall warning horn to operate, something that is clearly discussed in the POH, for those who bother to read it. (Note, electrical power is however required for Piper stall warning systems).

peterh337

20th Jul 2012, 14:46

The thing is that no matter how you toss these arguments, the smart thing is to carry a handheld GPS and a handheld radio.

If you don't carry these two, one day you are going to get seriously bitten on the bum, and that applies to all planes that have a single point of failure for the electrics, and that includes most twins also.

172driver

20th Jul 2012, 15:53

Oh and single engine Cessna's do not require power for the stall warning horn to operate, something that is clearly discussed in the POH, for those who bother to read it.

Oh yes, some do. 172RG for example (not that that was the most important piece of kit, though....).

The500man

20th Jul 2012, 16:02

The thing is that no matter how you toss these arguments, the smart thing is to carry a handheld GPS and a handheld radio.

For most people a mobile smart phone will do.

172driver

20th Jul 2012, 16:51

For most people a mobile smart phone will do.

Haven't seen a 121.5 App yet.....:E

Big Pistons Forever

20th Jul 2012, 22:39

BPF, I'm as much a stickler for the POH as the next guy, in fact the one of the a/c I mostly fly sits right next to me now.

However, nowhere in a POH have I yet found the phrase:

Brain - switch off

.

IMO following the POH doesn't equal "brain...switch off".

To me using your brain in the case of an inflight emergency is knowing the actions to take that will the most quickly and effectively stop/reduce your problem. Then assessing the problem and taking appropriate steps to deal with the situation.

So in the context of an electrical fire instead of as you suggest making a radio transmission with all the electrical services still energized and potentially about to make the situation worse, I think the best way would be to follow the POH electrical fire emergency checklist starting with immediately turning off the master to hopefully stop the ignition source.

If after completing the memory items of emergency checklist a decision is made that a radio call should be made then you should follow the POH emergency checklist to restore essential power. This will involve turning off all switches, pulling all CB's except the ones you need for one radio, looking for obvious indicators of where the problem is, like hot /melted switches/components, then turning on the master switch and making your call. These actions will minimize the chance of the smoke/fire reoccurring.

From a practical perspective the likely result of quickly removing power will be to stop the effected circuit from moving from the smoking stage to the on fire stage. Existing smoke/burning odor will likely start dissipating and so you can save re-energizing the electrical system until you get to the edge of the airspace of the nearest suitable airport and then turn on the master and make a Mayday call indicating your intentions and the fact that you are turning off all electrics at the conclusion of the radio call.

That would be the best case scenario. The worst case would be flames suddenly spurting out of the instrument panel. Again leaving power on is only going to make things worse and to me the idea that the first thing you should do in this situation is talk on the radio, just doesn't fit into BPF's brain.

IMO knowing and following the POH procedures combined with a deliberate assessment of the problem followed by actions appropriate to the situation is the best way to handle this emergency.

Finally re your note about the stall warning horn on the Retractable gear, constant speed prop equiped C172RG. Your are correct unlike the simple fixed gear fixed pitch prop C 172's which are ubiquitous at flying schools and clubs, this model does indeed have an electrically operated vane type stall warning horn. The Cessna Citation jets also all have electrically operated stall warning systems and my guess is that the average reader of this forum is about as likely to fly one of those as a C172RG.

However I will take your point that I was incorrect when I implied all C172's do not require electrical power for the stall warning system. I was thinking of the simple fixed gear series which have a reed type stall horn which activated by airflow though a fixed orifice in the wing leading edge. Systems can vary even among similar models which I think reinforces my point about reading the POH to understand how the aircraft you fly, works.

A and C

21st Jul 2012, 09:02

I think you have taken a very literal view to this thread, most of the people posting on this thread have taken the view to reply along the line of the developing situation and have given answers that reflect the action that they would take from the first hint of an unusual smell and the actions that they would take as the situation developed.

You have taken the view that the situation has already reached the large quantitys of smoke and may be flames and for this switching off the master switch is the first thing to do. The fact is that electrical problems don't usually go from nothing to full blown fire without some other form of indication.

I don't think that 30 seconds of investigation of an unusual smell followed by a distress call & 7700 transponder selection is a reckless course of action, followed by a structued electrical power down. If the situation is rapidly getting worse then of course the electrical master switch must go off at once. A low timer reading your posts might well get the impression that at the first hint of an unusual smell the electrical system should be switched off and creating an emergency that never existed. After all that smell could be the smoke from the power station that he had just flown over.

As to the state of pilot training in the UK I would rate it no better or worse than in North America, Australia, NZ & Northern Europe, all these country's have almost identical accident rates with the UK having weather that is less predictable than most.

What I am sure of is that a very low time PPL who has done a panic electrical shut down and now has the wife & kids in a state of very high state anxiety is not going to be very well placed to land the aircraft ( possibly flap less and with a manual gear extension ) what ever country he is flying in.

Big Pistons Forever

22nd Jul 2012, 02:07

A and C

If the situation is serious enough that you feel the need to make a Mayday call then I would suggest the situation is serious enough to follow the POH emergency checklist which starts with Master Switch Off. Then as I said in my last post after an assessment of the situation you may elect to follow the POH procedure for restoring power which are designed to minimize the fire risk to make a radio call.

Just to be clear I consider a fire inside the cabin one of the worst things that can happen to a GA pilot. The cabin of your average light airplane is full of plastic and foam which will give of noxious fumes when heated, the small size makes it impossible to move away from hot areas and renders use of the fire extinguisher problematical.

So for me if I smell the distinctive harsh odor of overheated wires which will generally be the first indication of the potential of a progression to a full blown electrical fire is going to be the cue to take immediate action to take away the ignition source.

Personally I have trouble understanding the idea is that the first thing you do when you think you are in trouble is send out a mayday. D & D are not going to be able to do anything to immediately make the situation better and the first thing they are going to do is to start asking questions to find out what is going on, which is going to encourage a conversation that will eat up time and in the worst case allow the odor to smoke to fire progression to take place, something that can happen quite quickly. Once the flames have started you are in a very very bad place........

Finally electrical power is not required for safe flight for the average GA light aircraft flight. Frankly any pilot that can't handle the possibility of loosing electrical power, which of course could happen for many reasons, is IMO not ready to be flying on his/her own, especially with passengers. They need more training.

So to summarize BPF's bottom line. If I am flying around and I smell burning insulation or other smells suggestive of electrical mayhem, I will immediately follow the POH checks starting with the turning the master switch off. I will then asses the situation and if I feel that no immediate danger of fire exists consider using the checklist procedure to restore power for essential services only which will probably be confined to only one Comm and I will land at the nearest suitable aerodrome. Since an electrical fire is started by electrical power I simply will not take the risk of leaving the aircraft electrically powered for any length of time if I suspect the possibility of a serious electrical malfunction.

Piper.Classique

22nd Jul 2012, 04:36

Second Big Pistons here. Most light aircraft don't need any electrical services to fly......they do need a functioning pilot not incapacitated by smoke. Just a thought, but how many of us have actually practised this sort of shutdown? Either in training or later?

peterh337

22nd Jul 2012, 06:44

As to the state of pilot training in the UK I would rate it no better or worse than in North America, Australia, NZ & Northern Europe, all these country's have almost identical accident rates with the UK having weather that is less predictable than most.I am not sure that follows directly, because there is risk compensation.

If someone is badly trained, but still has a brain (and you definitely do have to have a brain to pass the PPL exams nowadays) they will avoid doing more complicated trips. Most people are smart enough to know their limits. Confidence plays a very big part in flying and if you don't have it, you don't do the flight (usually).

My experience of FAA training (both PPL and CPL, as well as the IR) is that it is a lot more rigorous than over here, with emphasis on aircraft control, unusual attitudes, soft field / short field takeoff techniques in the PPL, etc. A US trained PPL can fly all over the USA (facilitated admittedly by their uniform airspace etc structure). A UK trained PPL knows how to fly Goodwood to Bembridge; Le Touquet is a major adventure which needs emotional support from pilot forums :)

The Americans also don't fly massive circuits. Some of the circuits at the UK coastal airfields are almost into French airspace, and the last one I saw had an instructor aboard :ugh:

A and C

22nd Jul 2012, 10:07

The system is so variable that I don't think that you can generalize about pilot standards across the country's that I quoted, as an instructor I get to see a lot of pilots some have come directly from flying schools in the USA , some have not been able to land a PA 28 on the 700m runway at Booker, others have been practically faultless and much the same picture is evident from UK trained pilots who fly out of large airfields.

The long distance flying thing is due to culture not ability with most clubs in the UK taking a " there be draggons" attitude to crossing the channel, add paperwork required and you have all the conditions for those who want to be seen as important turning crossing 25 mies of water into a black art.

Poor aircraft control in the circuit is due to a combination of noise abatement procedures and young pilots who think at they are airline pilots and want to be stabilized at 1000 ft and three miles, fortunately I teach at a place that has the option of a 600 ft oval circuit so we don't have those problems. Once a student has got the basics of landing the aircraft i try to get at a minimun one visit to a 500m runway for the short field work. As I said recently on another forum when needs dictated I have flown a 737 around a circuit that would have fitted inside the circuit at Booker so I have a lot of sympathy with your situation at your base airfield.

Technical matters are along with aerodynamics probably the worst taught subjects, I try to get at leaset one visit to the maintenance base during a PPL' s training as looking at an aircraft that is in pieces helps a lot with the understanding the construction and the systems.

We insist that a coppy of the POH is in the aircraft and have them avalable on PDF for the students to download.

To return to the electrical fire subject I think that the diference of opinion we between Big Pistons and myself is about 30 seconds before the master switch is turned off, he advocates a structured power up, ( with the possibility of re-starting the fire ) I advocate a structured power down with no re-powering of the electrical system. It is likely that in both cases after the first indication of posable electrical fire the system will be powered for about 60 seconds, in the case of Big Pistons that would be in two 30 second bursts.
This assumes that in both cases it takes the pilot about 15 seconds to react to the inital indication.
The other thing that is a factor in the UK is that unlike anywhere else that I can think of the ATC D&D cell can command instant help on the ground that will be awaiting you on arrival, and the proximity of airfields in the UK. I might take a slightly different attitude if I was in Alaska or out in the GAFA were any form of help was a long way away and there was practically no other air traffic.

Genghis the Engineer

22nd Jul 2012, 11:02

I'm in violent agreement with most of my learned colleagues above.

(1) Master switch off

(2) Fly the aeroplane

(3) Divert if nothing seems to be still burning, land immediately if something does still seem to be

(4) Fuel off ONLY if there seems any risk of fire near the fuel. But if that risk exists, just do it immediately, then fly the forced landing.

(5) IF TIME AND CAPACITY PERMIT, turn off surplus "stuff", then turn the master switch on long enough for whatever combination of RT / gear / flaps seem necessary and appropriate,then off again. If time and capacity don't permit, or there's new smoke as soon as the power comes back, just fly the aeroplane with the master off, and don't worry about the rest of it.

(6) Flapless landings in Cessnas are pretty much non-events - add about 5kn to the approach speed, and expect to use maybe 25% more runway. I've had a C150 electrical failure on a night cross country; the non-radio flapless night approach and landing that resulted, was stressful, but perfectly safe and nothing to write home about.

G

italia458

30th Sep 2012, 07:56

Looking up stuff regarding alternators and came across this thread.

I say I have to strongly agree with Big Pistons. You do NOT want to deal with a cabin fire. I sure hope I never have to experience it.

Even if you're just getting a bit of smoke coming out from under the panel you have no idea what the status is. There could be flames which are out of view from you and the fire could be already self-sustaining. The fire might not be self-sustaining at the point you first see the smoke and turning off the electric power could be the difference between the fire going out and the fire continuing to burn - taking 1 second longer could be that difference. Even when you have hindsight you still won't know exactly how it would have gone if you reacted differently. Do you really want to bet your life on being able to make that one transmission? - the one thing that does absolutely nothing to put the fire out and could make the fire worse. If you had the benefit of knowing exactly how the fire would progress and what the consequences would be for every action you take then you'd be able to determine if you do or don't have time to make a radio call instead of dealing with the fire. You don't have that benefit so why are you going to bet your life on it? I don't think people realize how bad a cabin/electrical fire is.

Like was mentioned previously, switching the ELT to on is an excellent idea. When ATC loses you on the radar and then sees your ELT come on I think they will understand that you might have an emergency - I mean, you just switched on your EMERGENCY Locator Transmitter. You should do that AFTER you have dealt with the fire.

UL730

30th Sep 2012, 11:45

What Ghengis said 1-5 and don't wear shorts.

The RAF don't wear growbags for the fun of it. I not suggesting NBC clothing but a nod in the direction of the correct clothing can be helpful in the event of a fire.

I've seen people flying in flip flops.:ugh:

JEM60

30th Sep 2012, 12:23

In my PPL days, I always wore flying gloves. Much more handy to put cockpit wiring fires out with, rather than bare skin. Only used to fly 172s etc., but always wore them in case........

peterh337

30th Sep 2012, 16:48

You could argue this like you can argue wearing a drysuit for over water.

Flying alone it's up to you what you wear but in the end it comes down to how "civilised" you want to make your flying with other people. Most people will not want to participate if the barrier is set at this level.

IMHO, a fire (that would go out of control and disable the pilot even if power is turned off promptly) on a well maintained certified aircraft is such a massively unlikely scenario that if you get it, your luck has truly run out.

On some homebuilts, it is less unlikely, and I recall reading of some homebuilts using aluminium fuel pipes to the engine, which is stupid because as the engine vibrates on its rubber mounts, the fuel pipe will break. A few AAIB reports I recall reading more or less said that the thing was on fire and the pilot was overcome by flames while still in the air. But certified types will have a high standard of fuel plumbing, which is not exactly rocket science...

Katamarino

30th Sep 2012, 22:25

I started this thread prompted by a question on a checkout questionnaire at a flight school I was going to rent from.

The answer that they gave in the end was, indeed, master off first; but they said that they would consider squawking 7700 then immediately turning off the master. Faster than a radio call, and they said that as soon as you hit 7700 it will transmit, it won't wait to be interrogated by primary radar...is this correct?

Fuji Abound

30th Sep 2012, 23:01

Katmarino - interesting question, i dont know the answer.

My gut feeling is with mode c the transponder will only respond when interrogated, 7700 or not.

With mode s extender squitter was implemented. This means the transponder will transmit certain information include the emergency call without being interogated.

So i think with mode c they would be wrong.

abgd

1st Oct 2012, 02:19

For mode c:

How would the radar identify the aircraft if it was not being interrogated? And would the dish be able to pick up a weak transmission if it was not pointing at the aircraft? And if it were pointing at the aircraft, wouldn't it be likely to be interrogating it?

italia458

1st Oct 2012, 03:50

The answer that they gave in the end was, indeed, master off first; but they said that they would consider squawking 7700 then immediately turning off the master. Faster than a radio call, and they said that as soon as you hit 7700 it will transmit, it won't wait to be interrogated by primary radar...is this correct?

I'm not a specialist in transponder electronics but I've heard from a few sources, including an IFR Center controller, who said that even if you have 1700 set and then turn the first digit's knob quickly through 7, you will hit 7700 and it will immediately set off alarms in all towers and centers that are picking you up on radar.

It's interesting that they'd tell you to squawk 7700 but not do a radio call. I can almost guarantee you that I'd be able to get out a mayday call before I'd be able to set my transponder to 7700. Plus, anyone who hears the mayday call will know where you are but if you squawk 7700 and immediately turn off the master, you will disappear from radar and no one knows where you are now!.. unless a controller happens to be looking right at your location when the alarm goes off. You've just wasted a few precious seconds for nothing.

I'm not sure if ATC has the capability to 'replay' their radar screen to see what just happened, I think that would be the only way to figure out your position. Someone who is from ATC would be the one to answer that.

I still advocate that you follow your checklist immediately and turn off the electrical power. If that fire is self-sustaining before you get the master turned off... you will be having a bad day. Don't waste time!

Tinstaafl

1st Oct 2012, 04:22

Older transponders used to transmit their reply even as a new code was being selected. Newer transponders delay their transmissions until a set period after digit was selected, giving sufficient time to complete the code selection.

Anyway, I'm in the 'Master OFF' camp. There's bugger all that ATS can do for me while I'm in the air & potentially on fire. On the ground, maybe, *if* I land at an airfield that has RFFS. But in the air? No. They'll get a hint that something is wrong when the transponder stops replying and I don't respond to their calls. Meanwhile I'll be doing what's necessary to deal with the problem.

If things deteriorate then the ELT can do much of the needed MAYDAY notification with the flick of a button. If things go OK then I can inform ATC after restoring power and cancel whatever alert phase they probably invoked when the plane went 'dark'.