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Don't use ABC fire extinguishers!

vic syracuse

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The only fire extinguishers that should be used around our airplanes are Halon and perhaps CO2. The ABC fire extinguishers typically found in the stores are highly corrosive.

We had an airplane come to the shop for its first CI. It had been built by one of the "pro shops", whose name I will leave off. We discovered that the 4 spar bolts were missing as per the Van's SB, which there is no excuse for, as the airplane was less than a year old. In the process of opening up the flooring to insert the bolts, we noticed a horrible amount of corrosion on everything, including spar botls, trim motor, trim springs, and all metal screws throughout the interior, and even the rear spar bolts. The pictures would make you cringe.

There was also a very fine powder throughout the interior of the aircraft, which I thought could have been fiberglass sanding residue. The corrosion looked like someone had spilled a bucket of acid inside the airplane, so we encouraged the owner to reach out to the builder.

He was informed that there had been a fire on the first engine start due to a disconnected fuel line and a fire extinguisher was used to put the fire out. Obviously the wrong type of extinguisher!

I spoke to an arson investigator today who has a metallurgist on staff. He says the airplane should not be flown without being completely disassembled and throughly cleaned, as the dust from the fire extinguisher is now everywhere and it is extremely corrosive.

I can only imagine that some of the dust has also penetrated into the avionics and can only guess as to its impact down the road. The dust is as fine as flour. I posted some pics on my FB page. https://www.facebook.com/vic.syracuse.7 or this link https://baselegphotos.shutterfly.com/pictures#n_5

Vic
 
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Vic,

After seeing the pictures (which are available now), is there anything that can be done with that plane now or is it destined for the scrape yard?

What should have been done after the ABC fire extinguisher was used? Is there anyway to clean up that mess?
 
As Vic said, ABC agents wreak havoc on aluminum and electrical. I'd try not to use them at all.

Get a Halotron or CO2 extinguisher.

My hangar has a 40 pound CO2, 10 pound CO2 and two 10 pound ABC extinguishers. I'll use the CO2 ones first, if still burning I'll use the ABCs as last resort.

Fortunately, I can see the fire station from my hangar if things got out of hand.
 
The Proteng looks interesting, appreciate it if you could answer a few questions:

Are you using the standard or the heavy duty model, the standard ruptures at 158 degrees F and the heavy duty at 194 degrees F.

What is the cost for this device?
 
Good posting, Vic. I saw the photos, and they are sickening.

Two years ago, the airport board here [Pryor Field (KDCU) Decatur, Alabama] mandated that each hangar have a standardized ABC fire extinguisher. I politely pointed out to the board that the powder would be highly corrosive to aluminum. The response was that they were concerned about stopping a large fire from spreading to other hangars and the airplane would be a total loss anyway.

I bought the required ABC extinguisher but also bought a Halotron and a CO2. I also bought a Halotron extinguisher and a CO2 extinguisher for my shop at home. If I have to extinguish a fire in my hangar I plan to use the ABC only as a last resort.
 
Vic,

After seeing the pictures (which are available now), is there anything that can be done with that plane now or is it destined for the scrape yard?

What should have been done after the ABC fire extinguisher was used? Is there anyway to clean up that mess?

I don't know all of the answers to this yet, Bill. The dust seems to be throughout the airplane, so things will continue to corrode over time. I was amazed at the how the cad plated bolts and screws are so corroded, including the rear spar bolts that were outside the cabin.

The GTN has stopped communicating with the G3X, and I tried everything I can think of with regards to configurations, so I don't know if it is beginning to affect the avionics too.

Vic
 
I don't know all of the answers to this yet, Bill. The dust seems to be throughout the airplane, so things will continue to corrode over time. I was amazed at the how the cad plated bolts and screws are so corroded, including the rear spar bolts that were outside the cabin.

The GTN has stopped communicating with the G3X, and I tried everything I can think of with regards to configurations, so I don't know if it is beginning to affect the avionics too.

Vic

Yup, just the beginning for the avionics and electrical problems. This is nasty stuff for those components.

BTW, don't have an ABC in your airplane either. Your lungs be finished too if you discharge that in the cabin.

Good of Vic to bring this topic up. May save someone's airplane in the future.
 
I'm glad I read this post, I rent a county hangar and they all have ABC fire extinguishers next to the door. I'm going to get a Halon or CO2 and put it in place of the ABC one, then put the ABC one in the corner.
 
Pictures don't seem to be visible to the general public, maybe you guys are already all Facefriends...
 
I once had an employee fire off one of those ABC extinguishers in the (non-aviation) shop to try to mask the smell of the joint he was smoking when a Security Guard knocked on the door. Dumbsh*t.

Vic is right, that powder is incredibly fine and goes _everywhere_. It will put a fire out but the damage it may cause can be a bigger problem. It's a poor choice of extinguisher around airplanes and confined spaces.

This guy was coughing and hacking for days afterwards too. Serves him right..:mad:
 
Extinguisher

Don,

To answer you question directly, the 194 deg temp is a resistance temperature. The average activation temp is ABOVE 300 degrees, hence the 350 deg I mentioned in my previous post on another topic.
As far as cost, there are several determining factors such as length and chem mixture. The average RV-6 application cost is roughly $699.
Proteng is currently on the road to do presentations in Southern California and will gladly meet with EAA chapters to give a fine demonstration of their product. They will meet with individuals as well. Really nice people. Anyone reading this post from CA to FL can call and arrange same with them when they drive back.
Contact Nichole at: 561-776-8364
 
very ugly


Wow - that's really ugly. I'm convinced. I have two halon extinguishers but they are quite big. Got them as part of an old datacenter decommission, and I think they are still good. Too heavy to keep in the aircraft, unless I need some ballast in the back.

I bought one of these "FireEx" extinguishers at the recommendation of another RV8 builder here in CH, but I really am not sure what's in it. I need to test it.

https://www.contrafeu.ch/fr/produits/fireex.html
 
I have the same comment - wow.
That is amazing. We just shut down a high rise bank and there is a pile of about 50 fire extinguishers. My idea was to just mess around with them but I will for sure be careful where they get sprayed. Hard to believe the corrosion.
 
No proper pre-purchase ???

When I look at those pix I can see why the original builder wanted to off-load the aircraft. They also indicate that the buyer did not have a proper, if any, prepurchase inspection performed before parting with his money. Honestly, it just continues to amaze me that buyers in the Experimental category regularly shell out huge dollars to buy questionable amateur-built aircraft without having any sort of inspection performed by a suitably qualified person. Mostly they just don’t want to outlay a few dollars to protect a major investment. In this case that obviously turned out to be a disasterous decision. I’ve performed 3 prepurchase inspections over the years and I didn’t recommend a purchase on any of them...there’s a lot of real junk out there in the backyard-built market.
 
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When I look at those pix I can see why the original builder wanted to off-load the aircraft. They also indicate that the buyer did not have a proper, if any, prepurchase inspection performed before parting with his money. Honestly, it just continues to amaze me that buyers in the Experimental category regularly shell out huge dollars to buy questionable amateur-built aircraft without having any sort of inspection performed by a suitably qualified person. Mostly they just don’t want to outlay a few dollars to protect a major investment. In this case that obviously turned out to be a disasterous decision. I’ve performed 3 prepurchase inspections over the years and I didn’t recommend a purchase on any of them...there’s a lot of real junk out there in the backyard-built market.


To be clear, this wasn’t someone unloading an airplane. A shop in Florida was paid to build it and had a fire during the first engine start and mentioned it to the buyer and said they thought they cleaned it up.

I’m sorry, but A&P’s, and especially IA’s, are supposed to understand the corrosive effects of the wrong fire extinguishers in an aviation environment.

If you really want to get your head spinning, we also discovered the control column front attach bracket had one bolt not completely inserted and the other bolt did not even have a nut on it. It was near imminent failure which most likely could have had disastrous results. I don't think it would be very easy or even feasible to control the airplane when/if this bracket came loose from the spar.

Link to pics is attached. In one you will see the two bolts that hold the forward part of the control column to the spar. You will see one bolt inserted and one standing quite proud. When the seat pan was removed you could see that one bolt was not even through the spar and the other bolt did not have a nut on it!

https://baselegphotos.shutterfly.com/pictures#n_5


Vic
 
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The thing that really makes this story good in the end, is that they brought it to you, Vic. I don't even want to think about the ramifications to the pilot, the family, and then to the RV community, the insurance pool, and on and on, if you weren't brought into the picture. There are so many ways this could have completely never been brought to anyone's attention and had disastrous results. It's great that you are who you are, to this community.
 
I've been saying this for years:


My nickname for ABC extinguishers is:

"Corrosion In A Can"


I finally saw some proof. Thanks Vic!
 
Yikes!

I?m betting this will get sticky between the parties, and I bet the owner is just sick, but from a case study standpoint, it?s really valuable. Thanks for sharing.
 
I look at this totally in a different view. ABC fire extinguishers are good fire extinguisher. They do an excellent job on electrical fires! When I pull that pin On my ABC fire extinguisher I figure the airplane belongs to the insurance company. Halon is good, but you take a chance of suffocating yourself. I have heard people say there is to much air flow for that to happen. If that is true then it isn?t going to put out your fire either. On more thing, if you have a fire behind your dash and try and use Halon it will settle to the floor very fast. Just not a good choice IMHO. Just some food for thought! I just want to make it to the ground to fly another day.
 
Two different topics here. Fire while flying and fire on the ground.

Original topic is use of ABC fire extinguisher due to fire during first engine start (ON THE GROUND) and resulting corrosion due to the ABC powder in the airframe.

The fire while flying topic should be discussed in another thread.
 
Homework needed

I look at this totally in a different view. ABC fire extinguishers are good fire extinguisher. They do an excellent job on electrical fires! When I pull that pin On my ABC fire extinguisher I figure the airplane belongs to the insurance company. Halon is good, but you take a chance of suffocating yourself. I have heard people say there is to much air flow for that to happen. If that is true then it isn’t going to put out your fire either. On more thing, if you have a fire behind your dash and try and use Halon it will settle to the floor very fast. Just not a good choice IMHO. Just some food for thought! I just want to make it to the ground to fly another day.

I think you seriously need to do some homework on Halon (and ABC powder) before you make such comments. Much of what you say is incorrect. Halon is used by the military in tanks, submarines, and aircraft because of its unequalled advantages in quickly and effectively suppressing fires in confined situations. It was even used in the space shuttle. Halon is unique in that it does not function by reducing oxygen levels at the source of the fire...it actually disrupts the combustion process itself. So it does not need to deplete oxygen levels to extinguish a fire.
ABC extinguishers are not recommended for use in aircraft. Apart from the fact that ABC agents can cause irreparable corrosion, inhaling the powder can cause choking and lung damage and in a very confined space such as an RV cockpit all vision could be totally obscured. Halon on the other hand will not obscure vision.
The reason for the push to replace Halon comes solely from its ozone layer depleting characteristics. However as an effective fire extinguishing agent for use in confined spaces NOTHING comes close to it. Pound for pound it is also considerably more effective in terms of rapidly extinguishing a fire than any other extinguishing agent. Typically you’ll need over 2 kg of CO2 to achieve the same result as 1 kg of Halon.
 
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What about BC extinguishers?

Think I read on here that the A component in ABC extinguishers caused the corrosion and that BC extinguishers (mine is white) didn?t. For in the hangar anyway I have Halon in plane.
 
I recall reading halon is not such an asphyxiation hazard even in confined spaces, but I'm too lazy to look it up now so I'll just share my unsubstantiated memory.
 
BC only?

I have both, a small ABC and a bigger BC only in my hangar. They were provided by the hangar builder.


2 airplanes are in there. A flying Cessna and the RV-8 project.


Reading this thread, it isn't reassuring to use the ABC inside the hangar...


How about the BC only?? it's indicated that it's Sodium Bicarbonate, you know, the stuff that absorbs odors or used in bakery...???


Anyone know how corrosive this would be to our planes???
 
How about the BC only?? it's indicated that it's Sodium Bicarbonate, you know, the stuff that absorbs odors or used in bakery...???

Anyone know how corrosive this would be to our planes???

This is exactly what I want to know too. I was at our local Fire ext shop and the guy told me that the pure Sodium Bicarbonate B:C extinguisher should be fine for my plane. Since there's no wood in there.

He also told me that Halon extinguishers has to be installed upright since the Halon will eat away at the o-ring and start leaking over time. Is this a fact...? :confused:
 
This is exactly what I want to know too. I was at our local Fire ext shop and the guy told me that the pure Sodium Bicarbonate B:C extinguisher should be fine for my plane. Since there's no wood in there.

He also told me that Halon extinguishers has to be installed upright since the Halon will eat away at the o-ring and start leaking over time. Is this a fact...? :confused:

I recall the same thing being discussed here many years ago, which is why I put a BC extinguisher in the hangar, and a Halon extinguisher in the plane. Then, of course, the county comes along and insists that the hangar owner install an ABC extinguisher. Sigh. Well, at least I marked it "NOT FOR USE ON AIRCRAFT", but I doubt anyone would pay any attention in the event of a fire.

I'm skeptical that someone would design a fire extinguisher such that the contents of it "eat away" at the containment system. That seems like it'd be pretty bad engineering.
 
On the topic of Halon, the asphyxiation hazard is not zero. I once had to use a large 150lb ground halon bottle that you see at airports to put out an engine fire, outside on the ramp, and I was coughing like I decided to start smoking with an entire pack at once. I wouldn't want to be flying and dealing with that and a fire. Had a nasty cough for days afterward too.
 
BC Fire Suppression

Here's what ansul puts in their BC fire suppression equipment:

Sodium Hydrogen Carbonate 144-55-8 60 - 100%
Calcium carbonate 471-34-1 1 - 5%
Attapulgite 12174-11-7 1 - 5%
 
Toxic decomposition materials...

xcape,

I used to know this stuff better when I taught about it. But the takeaways:

Halon is great at stopping fire by interrupting the chemical reaction of O2. Great!

The decomposition products generated with the chemical reaction with fire are toxic. Boo!

Bromides & bromine, fluorides & fluorine, chlorides & chlorine. Halon 1301 & 1211 make about the same stuff. Our lungs REALLY don’t like these things (Eyes don’t like them much either). Especially in a confined environment like a flight deck or GA cabin. I would teach donning the smoke hood or O2 mask/goggles before releasing the halon bottle. You experienced how bad it can be in an open air environment. Glad you’re ok.
 
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ABC fire extinguishers

Okay, an ABC extinguisher is not the best extinguisher to use on an aluminum airplane because the extinguishing chemicals are highly corrosive to aluminum.

The ABC letters are only indicators of what that extinguisher will put out. A: wood and paper, B: flammable liquids and C: electrical fires which become either B or C once the electricity is turned off. For exotic metals like magnesium, sodium you need a class D extinguisher.

Halon does not displace oxygen in a fire. The Halons, chlorine, bromine, florine and a few others somehow attach themselves to a radical molecule in the fire chain and extinguish the fire. The process is not totally understood why.

Remember your old fire triangle? To have a fire you need fuel/oxygen/source of ignition. To put the fire out you break the triangle! Halon dosen't do any of those things but the fire extinguishes. So the scientists think there is a fourth part of that triangle. A free radical.

2006 RV 6A sold
2010 RV 8A sold
2017 RV 12 sold
2020 RV 14A flying
 
Here's what ansul puts in their BC fire suppression equipment:

Sodium Hydrogen Carbonate 144-55-8 60 - 100%
Calcium carbonate 471-34-1 1 - 5%
Attapulgite 12174-11-7 1 - 5%

So is this good or bad for a plane...? What about a pure Sodium Bicarbonate B:C extinguisher? Good or bad?
 
This is exactly what I want to know too. I was at our local Fire ext shop and the guy told me that the pure Sodium Bicarbonate B:C extinguisher should be fine for my plane. Since there's no wood in there.

He also told me that Halon extinguishers has to be installed upright since the Halon will eat away at the o-ring and start leaking over time. Is this a fact...? :confused:

Mr. Vic, Please help. Can't find the answer on here. And nobody seems to really know. :cool:
 
Element Extinguishers

Antique Fire extinguishers are a problem.
Ever since the "Elements" came out I now no longer have ABC's. I do have a couple of halons hanging around somewhere.
I had a friend that used to service fire extinguishers for a living. Thousands per year. Factories, hospitals, repair shops, you name it. He did it for about 15 years servicing all makes and models.
He said that at least 90 percent of the powdered units he tested had compacted powder in the bottom of the bottle. The unit needs to be taken out of it's holder once a month and turned upside down and taped on something to keep the powder loose. After banging it on something, test it by rocking it back and forth, you should be able to feel the shift of the powder. HEY! better yet throw it away and get a better one.
If you try to fire off a unit that has set for a year or so (or God only knows), like they all do unless regulated by OSHA. It will probably fail to put out much powder as the hose will get plugged up. We proved his knowledge by trying one I had in "my" own shop. Bam the little sucker didn't work.. Just PHTT and no more.
Your mileage may vary, But, I've got Elements now and not looking back.
Oh, By the way if you discharge an ABC you're not going to get it recharged cause nobody wants to do that anymore.
Life's to short to be burnt up. I've been blown up twice and don't want to again. Both times got burnt up pretty bad.
My three cents worth
Art
 
Element Extinguishers

Antique Fire extinguishers are a problem.
Ever since the "Elements" came out I now no longer have ABC's. I do have a couple of halons hanging around somewhere.
I had a friend that used to service fire extinguishers for a living. Thousands per year. Factories, hospitals, repair shops, you name it. He did it for about 15 years servicing all makes and models.
He said that at least 90 percent of the powdered units he tested had compacted powder in the bottom of the bottle. The unit needs to be taken out of it's holder once a month and turned upside down and taped on something to keep the powder loose. After banging it on something, test it by rocking it back and forth, you should be able to feel the shift of the powder. HEY! better yet throw it away and get a better one.
If you try to fire off a unit that has set for a year or so (or God only knows), like they all do unless regulated by OSHA. It will probably fail to put out much powder as the hose will get plugged up. We proved his knowledge by trying one I had in "my" own shop. Bam the little sucker didn't work.. Just PHTT and no more.
Your mileage may vary, But, I've got Elements now and not looking back.
Oh, By the way if you discharge an ABC you're not going to get it recharged cause nobody wants to do that anymore.
Life's to short to be burnt up. I've been blown up twice and don't want to again. Both times got burnt up pretty bad.
My three cents worth
Art
By the way. Vic you nailed a big problem with ABC units.
 
Element extinguisher

I have these in my classic cars. I wouldn’t consider it for my airplane though. You light it like a road flare and can’t put it out after lighting it. Puts out a heavy smothering smoke that extinguishes fire.
 
Halon is a gas.

So no matter what position the bottle is in, it will be touching the o-ring.


So I don't see how the position of the bottle matters.
 
Lets not loose sight on the bigger risk here. A fire, especially in flight, is potentially fatal. Fire will also ruin the airframe. I'd rather blow off an ABC extinguisher and scrap the airframe than watch the whole plane burn, wreck the hangar. Worst case, die from a cabin fire in flight

I suppose my point is the wrong extinguisher is significantly better than no extinguisher.
 
There's a bit of philosophy embedded in these discussions about what the fire extinguisher is for.

The fire dept folks who show up at our industrial sites at work don't look at them the same way that most people I talk to see them. For our first responders, the primary purpose of a fire extinguisher isn't to put the fire out, it's to create a safe pathway to an emergency exit.

If, in the process of doing that, it puts the fire out, then that's a bonus.

But the worst use of an extinguisher is to deplete it by unsuccessfully fighting a spreading fire, and then be cut off from escape. Priority 1 is getting the heck out.

Part of that viewpoint includes acceptance that if a fire has become large enough to require consideration of an emergency exit, it's probably also large enough to condemn whatever it was that was burning, and anything after that is the insurance company's problem.

So the downside of an extinguishing agent which causes a corrosion problem several years down the road just isn't even a consideration because the thing the fire extinguisher was pointed at was already slated for replacement before the pin was pulled anyway.

Everyone in this thread is worried about being able to use the airplane again. The people who mandate the extinguishers are worried about threats to life and, secondarily, unburned property.

If the City is mandating ABC fire extinguishers in hangars, they're probably following the same philosophy.

- mark
 
Don’t forget, if you use a fire extinguisher in an airplane cockpit, you want to be able to continue to breathe. An ABC fire extinguisher will probably not allow that. Halon, which is designed to allow discharge in occupied areas and which will not displace oxygen or otherwise asphyxiate you, is the only viable choice.
 
BC Fire Suppression

So is this good or bad for a plane...? What about a pure Sodium Bicarbonate B:C extinguisher? Good or bad?

I don't believe anyone makes a "pure sodium bicarbonate" fire extinguisher.

from Amerex:

Sodium bicarbonate 205-633-8 Not Available 144-55-8 >92
Attapulgite clay 601-805-5 Not Available 12174-11-7 <5
Sericite
Potassium aluminum silicate
310-127-6 Not Available 12001-26-2 <2.5
Silicone oil
methyl hydrogen polysiloxane
NA Not Available 63148-57-2 <0.5
 
I didn't see this mentioned. Forgive me if it was.

Firegone foam extinguisher

We used to carry these on Blake's store, but they're available everywhere, including Home Depot, Walmart, etc. AND CHEAP!!!!! $12 to $15 at most stores.

According to the literature, the foam is non-toxic and non-corrosive. (Those terms are relative... don't eat the stuff, and don't use it in place of LPS 3.)

I've sprayed one at the shop and it seemed quite satisfactory. And easy to clean up. And didn't suffocate me. And it stays where you spray it, mostly, aside from some run off.

In flight, you could spray the fire... or spray it on your legs, hands, etc. if the flames were encroaching on your skin. That is something to consider.

The only down side to this type of extinguisher is that they WILL FREEZE in cold weather.

I have no skin in the game here, but I do think that I'd prefer a foam over dry chemical ABC every time. And over Halon in most cases, simply due to the high cost of Halon.

YMMV. Fly safely!
 
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