Andy,

Good advice, thank you. Only one point; after it happened the first time, I did change out the turbine, ECU and temperature probe (as the lead was badly burnt). I did not change the pump or the solenoid.

I agree with your black soot statement. The sound as you say, may very well be the kero catching fire - when the fire start it's like a 'rich' IC engine trying to burn off an over supply of fuel. After the last time I had the feeling that with flames also coming out the tail pipe at the back of the jet, that it was almost like an afterburner effect - in other words, burning fuel behind the turbine. (Once had the same situation with diesel pumped at idle with as make system).

I will run some tests and see if I can reproduce the situation under a prepared (controlled) situation, but I guess these will all be without the bypass. So if I can't get it to do it like that, I'll be back to the bypass theory. Should this happen I will then take one of my other turbines (I have 5 of the same engines) and install it completely into this model - and try again.

Cheers,

Jan