Has anyone on here discharged a fire extinguisher in flight?

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rudy
I'm interested in hearing about it if you have!

Any in flight fire stories are welcome actually.
 
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Not in flight, but squirted a small Halon extinguisher into the engine compartment after fuel in the bottom of cowling caught fire during a cold weather start. Should have preheated, but really wasn't an option. It was impressive, about a 1/2 second squirt of the extinguisher through the oil access door (C-150) and the fire was out.

Brian
 
Similar situation. I over-primed a Cessna in the middle of winter. The fuel fell out the bottom of the carburetor and somehow ignited. I ran for the fire extinguisher next to the fuel farm, but it didn’t work. I don’t know if the thing was frozen or not charged or what. The fire burned itself out after a few seconds – but when you’re in the midst of something like that, it seems to take forever.
 
Not exactly in flight, but here is an example in the cockpit:

 
In flight or on ground, Halon (if you can get it) or Halotron (its replacement) is what you want.

It doesn’t conduct electricity, isn’t toxic, and works extremely well.

Don’t get the CO2 or Powder type. Toxic in a small enclosed space and the powder is corrosive.
 
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This doesn't really count, but yes, we fired two fire extinguishers into number four engine about 200 miles out over the Atlantic on our way to Europe at night. Talk about pucker time! Fire warning came on, copilot shut down the engine and fired bottle 1, then the remaining bottle, and the fire warning continued. We started losing altitude as soon as the engine stopped. Turned back toward land, declared an emergency as everyone who could stared out the window to see if there were any flames. No one had ever successfully ditched a C-130, and if anyone jumped, they would never be found.

It turned out to be a failure in the fire warning system.

In a small plane, only once had smoke in the cockpit from an electrical fire. This was a flight review in the owner's C-150. He immediately shut off the master and returned to land. Uncontrolled airport.
 
Many years ago the Army came to the realization that one of our major computer rooms at APG didn't have a fire impression system. They ordered us a bunch of large Halon hand extinguishers. Then just to make sure we knew what to do, they brought some more Halon extinguishers in and set pan fires out behind the building and let all those with computer room access take turns putting them out. I can't even imagine what that all cost (and the damage to the ozone layer).

Halon is pretty nifty stuff.
 
One of the places I used to work at, had a CO2 system for the tape room. If the alarm went off, you had 30 seconds to either get out or don an SCBA, before the system fired. There were enough liquid CO2 bottles that if it fired, it would take less than 10 seconds to run the room atmosphere to 90% or higher CO2.
 
Craig said:
One of the places I used to work at, had a CO2 system for the tape room. If the alarm went off, you had 30 seconds to either get out or don an SCBA, before the system fired. There were enough liquid CO2 bottles that if it fired, it would take less than 10 seconds to run the room atmosphere to 90% or higher CO2.
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Note that with either Halon or CO2, the goal isn't to displace the oxygen (though if your room is tight that may indeed be a problem at least in some areas). Halon interrupts the chemical reaction of burning. CO2 primarily operates by cooling things down below where they'll burn.

Back when I was a fireman I learned there are four things you have to have to have a fire: Heat, Fuel, Oxygen, and a Battalion Chief. Take away any one and you can't have a fire.
 
Craig said:
One of the places I used to work at, had a CO2 system for the tape room. If the alarm went off, you had 30 seconds to either get out or don an SCBA, before the system fired. There were enough liquid CO2 bottles that if it fired, it would take less than 10 seconds to run the room atmosphere to 90% or higher CO2.
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Most gaseous supression systems using Halon, and its replacements like FM-200, are sized to produce a 10-12% displacement of oxygen in the protected space. Since the air is already 80% nitrogen, the added fire retardant effectively stops combustion. At that concentration, the gas products are generally not harmful provided the space is evacuated promptly.

I don't have any experience with CO2 systems, because in the era in which I built data centers, it had almost always been superseded by Halon and later products.
 
3393RP said:
Most gaseous supression systems using Halon, and its replacements like FM-200, are sized to produce a 10-12% displacement of oxygen in the protected space. Since the air is already 80% nitrogen, the added fire retardant effectively stops combustion. At that concentration, the gas products are generally not harmful provided the space is evacuated promptly.

I don't have any experience with CO2 systems, because in the era in which I built data centers, it had almost always been superseded by Halon and later products.
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flyingron said:
Note that with either Halon or CO2, the goal isn't to displace the oxygen (though if your room is tight that may indeed be a problem at least in some areas). Halon interrupts the chemical reaction of burning. CO2 primarily operates by cooling things down below where they'll burn.

Back when I was a fireman I learned there are four things you have to have to have a fire: Heat, Fuel, Oxygen, and a Battalion Chief. Take away any one and you can't have a fire.
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With CO2, you displace the oxygen. While there is some cooling from the adiabatic expansion of the carbon dioxide leaving the extinguisher, it primarily smothers the fire.

With halogenated extinguishers such as Halon, the halogens inhibit the oxidation of the fuel- it interferes with the chemistry. IIRC, it interferes with the production of free radicals. A long time ago, carbon tetrachloride (actually listed as a type of Halon!!) was used in fire extinguishers. Newer Halon formulations and its replacements are less toxic. Halon doesn't need to displace oxygen to be effective.

en.wikipedia.org

Carbon tetrachloride - Wikipedia

en.wikipedia.org en.wikipedia.org
 
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3393RP said:
Most gaseous supression systems using Halon, and its replacements like FM-200, are sized to produce a 10-12% displacement of oxygen in the protected space. Since the air is already 80% nitrogen, the added fire retardant effectively stops combustion. At that concentration, the gas products are generally not harmful provided the space is evacuated promptly.
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No, Halon systems do not work by reducing the oxygen below that is necessary for free burning. It inhibits the chemical reaction in fire. The flooding is purely to assure it gets to all the places that there might be fire.

In fact, after a halon dump (not a fire), the people in the adjacent offices found they couldn't light their cigarettes.
 
halon is impressive stuff. . it literally almost "seeks" out the fire when its discharged. .
 
Craig said:
One of the places I used to work at, had a CO2 system for the tape room. If the alarm went off, you had 30 seconds to either get out or don an SCBA, before the system fired. There were enough liquid CO2 bottles that if it fired, it would take less than 10 seconds to run the room atmosphere to 90% or higher CO2.
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There is a vault like that at Univ of OK in the library. It was about a 20x30 metal room with one door and we were told the same thing, roughly 30 seconds to exit before the door auto closed and fire suppression system fired off. Room had rare artifacts and things like a Gutenberg Bible and works from Isaac Newton (Principia Mathematica).
 
We had a button in one of our machine rooms that said "Press this button every 50 seconds to avoid Halon discharge." I suggested we get someone whose job it was to stand there and push the button.
 
flyingron said:
We had a button in one of our machine rooms that said "Press this button every 50 seconds to avoid Halon discharge." I suggested we get someone whose job it was to stand there and push the button.
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I thought it was every 108 minutes.

Nauga,
brought to you by the numbers 4, 8, 15, 16, 23, and 42
 
We've got Foam Abort buttons in our hangars, but one has to keep them pushed until the FD can disarm the foam system. Supposedly, they can do it in about 10 minutes after getting there.
 
flyingron said:
No, Halon systems do not work by reducing the oxygen below that is necessary for free burning. It inhibits the chemical reaction in fire. The flooding is purely to assure it gets to all the places that there might be fire.

In fact, after a halon dump (not a fire), the people in the adjacent offices found they couldn't light their cigarettes.
Click to expand...
I misspoke when saying it displaced oxygen. It was the percentage of Halon by volume of the space which inhibited the fire. It's been a long time since those days, and my brain is being effected by entropy.

:biggrin:
 
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