Ive got a Desert Aircraft DA50 and I want to wire in an ignition kill switch.

I could just add a switch that will disconnect the ignition battery, but with my other gas engine (a Quadra 42) I cut the engine by shorting the LT lines (ie the ones comming from the magnetic pick up).

The advantage of shorting the LT lines as oppose to disconnecting the battery is that if the switch fails (ie goes open circuit) then the engine continues to run where as with the 'disconnect' method a failed switch would stop the engine.

...The problem I have is that the DA50 has three LT lines where as I would normally expect either 2 lines or 1 line (using case as earth)

Does anyone know how DA have wired up these LT lines and if its possible (ie without damaging the module) to cut the engine by shorting the LT lines.

Thanks

David Bevan