Fire Bottle in engine compartment

Tfoster100

Tfoster100

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Tim
I've read a few posts and older articles about having some sort of breakable bottle in engine compartment that can be activated in case of fire in engine. Are those still used and what are thoughts on that. Seems like a good idea. I know there is extinguisher in cabin. But seems like if in flight you would really want to try to extinguish in engine compartment.
 
The compartment fire extinguishers I'm familiar with have frangible discs (replaceable part of bottle) that are broken by an electrically activated squib (explosive).
 
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I worked several years as a mechanic on IndyCars.

They have Halon 1301 fire bottles and stainless steel tubing routed to discharge nozzles in the engine compartment. The bottle was driver activated. I think the bottle held six lbs of agent.

The engine compartment on the car was tightly sealed for drag reduction. This also made the fire bottle effective. There has to be an 11% concentration of the Halon for it to prevent combustion of flammables IIRC.

With the large amount of airflow through a small aircraft's engine compartment, I would think using a gaseous fire retardant would be problematical.
 
3393RP said:
With the large amount of airflow through a small aircraft's engine compartment, I would think using a gaseous fire retardant would be problematical.
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It is. But that is why many of the airplane fixed extinguisher systems only cover the accessory section and not the engine itself.
 
Tfoster100 said:
I've read a few posts and older articles about having some sort of breakable bottle in engine compartment that can be activated in case of fire in engine. Are those still used and what are thoughts on that. Seems like a good idea. I know there is extinguisher in cabin. But seems like if in flight you would really want to try to extinguish in engine compartment.
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The only piston airplanes that I have come across with fixed extinguisher systems have been radial engines.

Like Glenn said, there is usually a blowout disk of some sort that is inspected as part of the preflight.
 
Fire extinguisher bottles are not typically placed inside the engine compartment. In fact I cannot think of any that are. They are placed outside of the engine compartment and have tubing that leads to nozzles within the actual compartment.
 
SkyDog58 said:
Fire extinguisher bottles are not typically placed inside the engine compartment. In fact I cannot think of any that are. They are placed outside of the engine compartment and have tubing that leads to nozzles within the actual compartment.
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True. But even then, the extinguisher nozzles are typically behind the power section.

My Beech has a single bottle in the right landing gear well with piping that goes to both engines.
 
My Bonanza came to me with a Fire Protection System - 3x Fire Detection probes with a red Fire warning ligt, and a Halon bottle, activated by a guarded switch adjacent to the Fire Warning light. Trying to figure out where to get it recharged. Its discharge is a braided stainless line leading down by the throttle body on the bottom of the engine; assume this is because it is the most likely place for a fire.

My A&P assures me he can easily replace the squib; this, told when I asked bout how we could reasonably assume it would work when needed.

The brand, according to the logs, is American Standard.

My plane was once, long before my ownership, a "demo" plane for an avionics outfit, had a mess of Narco's best once.
 
SCCutler said:
My Bonanza came to me with a Fire Protection System - 3x Fire Detection probes with a red Fire warning ligt, and a Halon bottle, activated by a guarded switch adjacent to the Fire Warning light. Trying to figure out where to get it recharged. Its discharge is a braided stainless line leading down by the throttle body on the bottom of the engine; assume this is because it is the most likely place for a fire.

My A&P assures me he can easily replace the squib; this, told when I asked bout how we could reasonably assume it would work when needed.

The brand, according to the logs, is American Standard.

My plane was once, long before my ownership, a "demo" plane for an avionics outfit, had a mess of Narco's best once.
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Was that an STC?
 
Fearless Tower said:
True. But even then, the extinguisher nozzles are typically behind the power section.

My Beech has a single bottle in the right landing gear well with piping that goes to both engines.
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Excuse my round engine ignorance, please correct me where I'm wrong.

You mention "behind the power section".

The cooling air is directed over the cylinders and out the cowl flaps, right? Is there an effective barrier aft of the cylinders that isolates the carburetor, magnetos, generator, etc?
 
3393RP said:
Excuse my round engine ignorance, please correct me where I'm wrong.

You mention "behind the power section".

The cooling air is directed over the cylinders and out the cowl flaps, right? Is there an effective barrier aft of the cylinders that isolates the carburetor, magnetos, generator, etc?
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There is usually a baffle plate between the exhaust collector shroud and the accessory section on the back side of the engine.

If I can get out to the airport tomorrow, I'll take a photo of my engines since we have the cowling removed for the annual.
 
Here is a photo of an R-1830 on a DC-3 with the cowling removed.

The fire extinguisher protected area is underneath that polished section of cowling between the fire wall and that baffle plate behind the exhaust. The area from the exhaust collector forward is not protected.
 

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The photo answers my question, thanks.
 
Fearless Tower said:
Here is a photo of an R-1830 on a DC-3 with the cowling removed.

The fire extinguisher protected area is underneath that polished section of cowling between the fire wall and that baffle plate behind the exhaust. The area from the exhaust collector forward is not protected.
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Radial engine maintenance is one of the few holes in my A&P resume that I really want to fill.
 
Here's pictures of the fire system on my 414. Engine is TSIO520NB. The R2D2 looking thing is the fire bottle which sits back at the firewall. The big hose at the bottom mainly goes to the top front of the engine shown in second picture. A smaller hose branches off and goes to the front side of the accessories. image.jpeg image.jpeg
 
SkyDog58 said:
Fire extinguisher bottles are not typically placed inside the engine compartment. In fact I cannot think of any that are. They are placed outside of the engine compartment and have tubing that leads to nozzles within the actual compartment.
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True. The Gulfstream 1 had/has a fire bottle in each nacelle with crossover tubing to the opposite nacelle. The bottles are accessed through their own exterior panel. The panel, sight gauge and blowout discs can be seen in this pic:
http://g159hrm.com/_Media/ww_med.png
 
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