On Sun, 11 Oct 2020 07:18:06 -0700, Kenn Sebesta wrote:

Before I jumped on the camera train, though, I'd give careful
consideration to what it means to detect a fire. You might find that the
kind of fires you want to detect are far earlier than would be seen by a
camera. I don't have a firm concept of fire detection (What does it mean
to detect a fire? How do we even define "fire" in this context?) so I'm
at a loss for what are the precursors to a fire.

Good point: I know of a Duo that was burnt out on the ground. The fire
source was a binding wheel brake that, while the glider was being towed
out, ignited dry grass in the wheel box. This in turn melted plastic
(factory fitted AFAIK) fuel tubes running alongside the wheelbox to the
fuel cock in the cockpit, The wheelbox fire damaged the fuel tubes enough
to let fuel escape and burn.

I didn't see this: just the glider-shaped black patch on the airfield.
The fire spread fast enough that the owners were lucky to get the car
unhooked and away from the glider before it burnt as well.

I'm not saying that this particular ignition event could occur in the
air, just that a turbo or SLMG may well have potential ignition points
outside the engine compartment.


--
Martin | martin at
Gregorie | gregorie dot org