>the only way to keep the fire out is to keep the air out

>being able to shut the cooling air flow, at the exit or intake will help a

lot.

 

I'm trying to put this in perspective.

Assuming no way to shut off the intake air, is firing a halon extinguisher

in flight going to have ANY worthwhile impact on an engine fire? Keep in

mind that the fiberglass cowl is likely to be breached early on, thus any

control of airflow is lost. I'm beginning to think that the most important

issues here are detection, and removal of the source (fuel) and that an

extinguisher would be useful to save the plane once landed, but worthless

(and wasted) if used while airborne.

 

Not that I like the conclusion, but I tend to agree with this assessment.  Early detection and shutdown of the fuel sources is key. Containment of the fire - keep it out of the cabin, protect the flight controls, and protect the wiring for a restart when you have no other option than a rocky hillside - is also very important.

 

I have spare thermocouple inputs to the EM-2 in the area of the fuel rail and exhaust with temp limits set to trigger the engine alarm in the event of a high reading. It was the simplest approach.  Better would be to wire in a heat fused link to a separate alarm so you wouldn’t have to first figure out which channel is triggering the alarm.

 

I don’t know that having the engine in back is advantageous or not, but one disadvantage in the canard configuration (at least the Velocity) is the having the aileron push-pull cables running inside the cowling.  I have high temp cables that I intend to firesleeve, but they do have some sort of plastic outer sleeve which will likely burn/melt and could result in difficulties with control.

 

I have a SS sheet (I think 26 guage) backed by fiberfrax for firewall protection.

 

Al