Originally Posted by
wrench1
No. It's a free turbine. The only items driven by the Power Turbine on most PT6 fixed wing are the prop gov, PT ovspd gov, and PT tach/gen. Everything else is driven by the Compressor Turbine. My guess the reason for the AT igniter delay is more airframe electrical system related than anything else.
I understand it is a free turbine. My question related to fixed turbines/pistons and if seperate ignition was a carryover from those designs.
I suspect your point about the airframe electrical system is correct though.