Electrical Fire

[slick1537]

What are the indications of an electrical fire vs a regular fire. For example, you are flying along and you smell smoke, how will you diagnose it as either an electrical fire, or a regular fire?

[rick1128]

By the smell. Electrical fires have an acid like smell. The first thing I would do at this point is gangbar the electrical system and see if it goes away. If it does not, it is most likely a short somewhere between the battery and the master switch. Follow the checklist. If it does go away, I would turn everything off and pull all the CB's, turn the master switch on and wait, then turn one item on at a time and wait. when you get the smell back the last item you turned on is the problem.

[Guest pokey]

In flight fires are babababaaaad--no matter what started it. Electrical fires do have a certain smell to them as Rick pointed out. What is a "regular" fire? did you drop your cigar? lol just kidding. But the smell will usually give you some indication of what is burning, in any case, i would consider it an extreme emergency & land immediately & not mess w/ resetting any circuit breakers or electrical components--shut them ALL off, leave them off & land as soon as posssible. ( i must say my joke about fires: "always carry a pack of hot dogs & long sticks just in case, you dont want to waste a good fire").

 

Now about circuit breakers, there is alot of controversy about them in flight. Owner of airport that i used to be based at bought these 3 Russian seaplanes (BE-103,, look them up on the 'net if you want to see a really strange bird), and ALL of the circuit breakers were in a nose panel- inaccessable to the pilot. Now i got to digging into the regulations to see if in fact this was "legal" (they ARE US certificated planes) & low & behold? Only circuit breakers critical to the safety of flight are required to be accessable to the pilot. Now think about it, is there ONE electrical circuit that is critical to the safety of flight? answer?--NO. then i asked, what about electric landing gear? -- that my fine feathered friend is critical to the safety of the landing, NOT the flight--go figure !! Then i got to talking to a few of the airline pilots ( heavy iron pilots) & they informed me that alot of the airline rules do NOT allow resetting a popped breaker in flight. I would and have, but they frown on me for saying that.

 

 

in short, dont try to diagnose a fire in flight, land as soon as possible & enjoy your weenie roast

[PhotoFlyer]

I don't think I would be diagnosing what circuit the fire came from in the air. First of all, it takes a lot of your attention away from your primary job, FLYING. Second of all, if you do find the offending circuit, the fire might not go out when you pull the circuit breaker again. Third of all, if the original fire burned away the insulation around other wires you will have an even bigger problem on your hands since multiple circuits can start a fire now.

 

Better to just turn everything off, land safely, and then let maintenance handle the problem. If maintenance isn't available, then depending on the situation you might need to diagnose the problem, but you had better be on the ground and able to get away from the aircraft if it catches fire again.

 

Fire isn't anything to be trifled with in an aircraft. Depending on what's burning, the smoke can incapacitate a pilot in SECONDS! Even if it doesn't incapacitate, it can be so heavy that opening vents and doors can't ventilate the smoke fast enough and your outside view and view of the instruments (if they still work) can be obscured causing loss of control.

 

Just land and let the mechanics handle it.

[slick1537]

Well I was just reading is that water is conductive to electricity, so dumping water on an electrical fire if the source of current is still active, will only serve to aggravate the fire. Just something to know.

[Liner]

I thought I was always taught - white smoke for an electrical fire.

Maybe I'm "mis-remembering". Thanks George Bush for that word

[rick1128]

Maybe my point was not too clear. Follow the checklist procedures. HOWEVER, landing immediately MAY NOT be a viable option. It would be a shame to wreck a multi million dollar helicopter because of a bad $.02 diode. Also while you are flying to a suitable area, you may still need (not want) some electrical items. That is why you turn everything off and turn them one at a time.

 

As for resetting CB's, it depends on your company's policy or the procedures in the Flight Manual which ever is more restrictive. My personal policy is that unless the Flight Manual says not to, I will reset it ONCE. This does not apply to CB's you pull. You can reset them all day long if you want. As they were not popped, they were intentionally pulled.

[PhotoFlyer]

Forgive me, but unless you are IFR, what items do you NEED? Your right, landing immediately may not be a viable option, but if turning everything off stopped the fire you should have plenty of time to fly to an acceptable landing site. And I would rather shut everything off and make an emergency landing (no reason to crash unless your actually on fire) for a $.02 diode, then continue flight and play circuit breaker roulette because I *need* some piece of equipment turned on.

 

Edit: I have attached a NTSB accident report as a PDF from a crash that resulted from an in-flight fire in 2007. If you don't want to read the whole thing, check out section 3.1. For an easier read, AOPA published an article about this crash in the May 2009 issue of AOPA Pilot magazine.

 

AAR0901.pdf

 

Edit #2: If you want to see more of those accident reports (including the ENG crash in Phoenix) then click here.

Edited April 30, 2009 by PhotoFlyer

[rick1128]

Forgive me, but unless you are IFR, what items do you NEED? Your right, landing immediately may not be a viable option, but if turning everything off stopped the fire you should have plenty of time to fly to an acceptable landing site. And I would rather shut everything off and make an emergency landing (no reason to crash unless your actually on fire) for a $.02 diode, then continue flight and play circuit breaker roulette because I *need* some piece of equipment turned on.

 

Edit: I have attached a NTSB accident report as a PDF from a crash that resulted from an in-flight fire in 2007. If you don't want to read the whole thing, check out section 3.1. For an easier read, AOPA published an article about this crash in the May 2009 issue of AOPA Pilot magazine.

 

AAR0901.pdf

 

Edit #2: If you want to see more of those accident reports (including the ENG crash in Phoenix) then click here.

 

What you need depends on your judgment as the pilot and your location and situation. Each situation is different. Just because you do it one way and I do it another, doesn't make either of us wrong. We each looked at the situation differently. It is easy for other pilots to sit on the ground and tell you what you should have done, but they were not there and had a great deal more time to look at the situation than you did.

 

And YES I have had fires in flight, both electrical and non-electrical. I have been both VFR and IFR in these situations and had the need to utilize some of the electrical equipment. In each case I landed as soon as practical. In a couple of cases, landing immediately was not even close to be a viable option. So I am talking from experience. The electrical systems on the newer aircraft are much more reliable. But they still have problems from time to time.

[Darren Hughes]

I had an electrical fire in flight a few years ago. Best way to describe it is lots of white smoke and smells like burning plastic.

[Justin DBC]

From my limited experience....

 

Bottom line... If the POH says "land immediately", it's probably for a good reason. The only time I would want to try to diagnose the problem mid-flight is if I was over water, and that would only be after I had set myself up to ditch and only if it hadn't become so severe that it was an immediate threat to myself or my passengers. Wouldn't you end up getting screwed afterwards anyways if anything happend and you didn't follow the book? I can see what you're saying, but it just seems like too much of a gamble.

 

J-

[Guest pokey]

It would be a shame to wreck a multi million dollar helicopter because of a bad $.02 diode.

 

 

just being a wisenheimer here, but?

 

1) how much would the diode have to cost to verify wrecking a multi million dollar helicopter?

 

2) what is the maximum cost of the helicopter that can be wrecked for a 2 cent diode?

 

[AngelFire_91]

Air Canada flight 797 is the reason why the majority of 121 and 135 operators have policies to not reset circut breakers in flight, or only specific breakers can be reset.

 

I don't think when flying VFR there is anything I would absolutly NEED to have on. Personally if I wanted to troubleshoot, I'd find the nearest sutible site and set her down, then start pushing breakers and such. That way I could 1)Actually spend the time pushing breakers, waiting or troubleshooting without having to fly in a smoke filled cockpit, and 2)If I do catch on fire I can get the hell away from it without having a parachute on. My idea of fun is not flying around in a smoke filled cockpit with my eyes burning, butt getting hotter, not being able to breath, and whatever else.

 

Not saying any one way is right or the other, just my personal opinion.

 

But to answer the original question, It's mainly a smell issue. I was always taught the white smoke vs. black smoke thing too, until I had an engine fire of my own (in fixed wing) and now I can tell you, color is in NO way a good way of telling where the fire is. I also would STRONGLY advise against discharging the extinguisher in the cabin without adequite ventilation. Sodium Bicarb is an irritent and Halon is an Asphyxiant, and if you've ever breathed in a dry chem (Sodium Bicarbonate) extinguisher it's not a good time, you will caugh and choke on it. Imagine a feeling like driving down a dirt road with your head outside the car, behind a semi when it hasen't rained for 2 months.

[kodoz]

I read that AOPA article...just published in one of the last couple of issues. There's a link to it in their Safety Brief on electrical fires.

[rotorrodent]

.............. If it does go away, I would turn everything off and pull all the CB's, turn the master switch on and wait, then turn one item on at a time and wait. when you get the smell back the last item you turned on is the problem.

 

I wouldn't mess with success if I were you. Once everything is off and the smoke/smell stops, land the bloody machine ASAP, then once safely on the ground, do your trouble shooting. Then If you have isolated the problem, RISK mgmt call, to continue or call for help.

 

Your idea of trouble shooting in the air works for FW because they have no where to go in the immediate sense. However, in the RW, you should be able to land within a minute or two.

 

Fires inflight or on a boat requires immediate suppression. On boats at least, it's swim time!!!

 

IMHO

 

Cheers

 

rotorrodent

[rick1128]

I wouldn't mess with success if I were you. Once everything is off and the smoke/smell stops, land the bloody machine ASAP, then once safely on the ground, do your trouble shooting. Then If you have isolated the problem, RISK mgmt call, to continue or call for help.

 

Your idea of trouble shooting in the air works for FW because they have no where to go in the immediate sense. However, in the RW, you should be able to land within a minute or two.

 

Fires inflight or on a boat requires immediate suppression. On boats at least, it's swim time!!!

 

IMHO

 

Cheers

 

rotorrodent

 

Ask the guys flying off shore or in mountainous areas, landing immediately is not always an option. The pilot needs to keep in mind his total situation and act accordingly. It is like the story about the student pilot who was told the best way to conduct an emergency landing was to go between two trees to take the wings off, if he was forced down in a forested area. He had to make an emergency landing and put the aircraft between the only two trees in the pasture. He followed the procedure he was taught, but didn't keep in mind his total situation.

Edited May 1, 2009 by rick1128

[BOATFIXERGUY]

Not to keep this heated argument going, but any electrical fire has a simple solution. Here's the copy from a Bell L4 and is the same in any other bird I've flown:

 

3-7-B. EXCESSIVE ELECTRICAL LOAD

• INDICATIONS:

1. DC loadmeter indicates excessive

load.

2. Smoke or fumes.

• PROCEDURE:

1. GEN switch — OFF.

2. BAT switch — OFF.

3. LEFT FUEL BOOST circuit breaker —

Check in.

 

This is the procedure. Ya, you can trouble shoot all you want, but I don't want a smolder to become an inferno.

 

Just my .02

[gmsemel]

Smoke of any kind is not good, do what the check list for the aircraft you are flying says, and land ASAP. If VFR its not a major problem unless you are being burned, IFR, well then you have to try to Isolate the problem, let ATC know and declare an emergency. I would rather fill out a couple of forms and explain my actions {FAR-91.3 (}than getting really hurt or worse.

[rotorrodent]

Ask the guys flying off shore or in mountainous areas, landing immediately is not always an option.

 

 

agreed!!!

 

Rotorrodent

[West Coaster]

Only had an electrical fire once. My first indication was a wall of sparks raining down on my feet lol.

[Hedge36]

Only had an electrical fire once. My first indication was a wall of sparks raining down on my feet lol.

 

I had fireflies in the cockpit once, thought it was the same deal.

 

The thing to remember about Class Charlie (electrical) fires: they're short-lived. Most of the time the short will trip the breaker on the affected circuit before the electrical portion of the fire goes out of control. Within the published guidelines of the EPs in the POH and company policy, the general rule for a Class C fire is to secure power. Once that's done, the Class C portion of the fire is out. If you're lucky, that's all that'll happen.

 

HOWEVER, Class Charlie fires can quickly turn into Alpha or Bravo fires (depending on what's situated near the source of the initial electrical issue), and THAT is where you run into trouble. The smoke from the THHN and other compounds on the wiring insulation itself is toxic as hell, and obviously oil and/or fuel fires that started under Class C conditions... well, they suck all by themselves.

 

Point being, if you smell ozone, see the magic white smoke escaping from the instrument panel and the ammeter starts going hinky, you've probably got an electrical fire - but it doesn't matter unless you've got time to troubleshoot the problem. The likelihood is that the resulting NON-electrical fire will give you more issues than anything else. Just try to get the damn thing on the ground before you get your passenger to pull the trigger on that dry chem extinguisher.