Fire port on cowl

[Bevan]

Because of the size and weight of FWF fire suppression systems, I'm considering a small port (say one inch diameter) on the side of the cowl that one could easily push open (spring loaded to close from the inside) with a fire extinguisher hose if there ever was an engine compartment fire while on the ground. Anyone done this?

My thinking is, where does one aim the fire extinguisher when there's a fire in the intake or lower cowl area?

Bevan

 

[Mike S]

My thinking is, where does one aim the fire extinguisher when there's a fire in the intake or lower cowl area?

Bevan

Normal use of a fire extinguisher is to point it at the base of the fire.

In the case of an engine fire in an RV, this would probably be beneath the oil sump area.

Really, most any area below the engine with a somewhat direct view of the carb/FI should do pretty well.

 

[Snowflake]

Up the lower cowl opening? Would require bending down to get the extinguisher jet pointed up into it, but it would work.

A port on either side of the cowl below/behind the cylinders would have internal cowl pressure to keep it closed... I suppose it would be handy if you had to put a cowl fire out, but I think I can count on one hand the number of times i've heard of such a thing happening to an RV.

 

[Bevan]

Hi Rob,

I'm not sure I would want to crawl under a burning aircraft to spray into the cowl exit area.

Aircraft fire...Yes rare but just happened to an RV posted here recently. See

http://www.vansairforce.com/community/showthread.php?t=114797&highlight=fire

A few years ago there was a post shut down fire on the taxiway just down the way from your hangar. Not an RV but destroyed the aircraft none the less. Pilot shut down, got out, turned his back to talk to someone and didn't notice the smoke.

Anyway, we are required to carry fire a extinguisher on board. Fires are possible when on the ground. Just wondering if a "fire port" is the best way to make use of the limited resource (extinguisher). I wouldn't think the oil filler door would be very effective location to spray from, nor would the any of the cowl openings at the front.

Bevan

 

[Paul Tuttle]

I'd just give it a shot with the extinguisher where the opening is for the exhaust.
Anything that is going to burn will be in that area, gas, oil etc. These airplanes are so tightly cowled the area would be saturated with extinguishing agent.
These extinguishers have a pretty good reach of stream so you don't need to get that close.

If that doesn't work call your local ARFF crew over, we live for this stuff.

 

[Snowflake]

I'm not sure I would want to crawl under a burning aircraft to spray into the cowl exit area.

I don't think you'd need to get very far under the plane to get a shot up the exhaust intake... I suspect if I couldn't get that close, I wouldn't want to get close enough to push open a panel on the side of the cowling either.

A few years ago there was a post shut down fire on the taxiway just down the way from your hangar. Not an RV but destroyed the aircraft none the less. Pilot shut down, got out, turned his back to talk to someone and didn't notice the smoke.

Note also that he did have an extinguisher, knew he had fire when he got out, and used the extinguisher to put out the fire on the side of the cowling that it was visible from. Only after he stopped putting it out did he realize that the fire was continuing on the other side, and he had already emptied the extinguisher. There wasn't anyone else around to borrow an extinguisher from, so his best choice at that point was to back away. Unfortunately his wallet, cell phone, and car keys were in his jacket in the cockpit.

Just wondering if a "fire port" is the best way to make use of the limited resource (extinguisher). I wouldn't think the oil filler door would be very effective location to spray from, nor would the any of the cowl openings at the front.

The oil filler door would probably be quite effective. If you've ever set off an extinguisher, you'll know that it can fill a volume very efficiently from any opening. I agree the cowl openings at the front wouldn't be ideal though... The fire is likely to be below the engine, and anything shot through the front would have to get through the cylinder fins first.

 

[Bevan]

I stand corrected on the details.

Unfortunate all the way around. Also, sometimes when using a dry powder extinguisher, saving a little for a flare up doesn't alsways work as the powder can prevent the valve from closing completely. If you pick it up a few minutes later, it may have powder but no more pressure. Best to use the whole thing at once and clobber the fire. Have a second extinguisher on standby for any required second tries.

Contemplating a race car type built in system ( about 8 lb) with pre-aimed and mounted nozzles. I hate fire, so for me it's peace of mind.

Bevan

 

[gasman]

Most fire extinguishers that are mounted on the exterior of city owned hangars are very corrosive to aluminum, and will most likely render your airplane a total loss even after the fire is out.

But the fire will be out.

 

[RV7A Flyer]

Most fire extinguishers that are mounted on the exterior of city owned hangars are very corrosive to aluminum, and will most likely render your airplane a total loss even after the fire is out.

But the fire will be out.

Which is why I bought my own extinguisher of the proper type, mounted it next to the one the hangar owner hung (of the wrong type), and made big-*** labels for both of them...one says "NOT FOR USE ON AIRCRAFT" and the other "FOR AIRCRAFT USE".

I don't know why they put an ABC type extinguisher in all the hangars, and neither did they when I asked them...just "we have to put extinguishers in there" (the fact that I already had one in the hangar apparently didn't matter).