Originally Posted by
ww2birds
I've often wondered what's the fastest possible telemetry response to a flameout .. you could look directly at exhaust temperature, or the RPM or the pump voltage. I've always presumed that temperature would be the best, since the RPM response would be slowed by mechanical inertia, and the pump voltage (and the ECU code for flameout) only occurs after the ECU figures out what has happened and starts to take its own action.
But I've never done any actual tests .. and perhaps the time difference is only fractions of a second and would not really matter anyway.
I do like the idea of a stick shaker.
Dave
Dave,
The setup Paul described, which I use, works very well. The EGT > 300 to arm keeps the alarm from activating until after the engine is running. I think most ECU's shut down the fuel pump almost immediately if the EGT drops, so the pump voltage is a good trigger. Also, it activates every time you shut down the turbine, verifying it's set up correctly.
I suppose there are other reasons an ECU might shut down a turbine, such as overspeed or overtemp, but again, I think the ECU is going to kill the pump to do so.
Craig
PS: On my A-10, I have it set up to shake the left stick if the left engine fails and shake the right stick for the right engine. Unlike the rest of the programming, I thought of that myself.
