GA Turboprop

[uavmx]

In the 1990's United Airlines was taking deliveries of B-757 's and I had a Pratt & Whitney tech rep riding jumpseat with us on a trip. UAVMX, when he finished taking engine parameter readings I asked him the EXACT question you have raised about a 300-400 hp turbo prop we could afford in GA. His answer was as long as we machine the blades we cannot get the cost down. I asked about making ceramic blades and he said they were working on that, but I have not heard anything about it since then. Adrian Bewley

Yeah, that's obviously where the cost is tied up....not in the technology. Axial flow blades don't seem like that are all that complex to machine.....where as a blisk, or centrifugal compressor seems like it would be very difficult. But again, with all the automation today, all these CNC machines, etc, you'd think that the cost would have come down.

The outer housings are pretty basic, pressed/welded tubes essentially. I think the shafts would be expensive because of the trueness required and often times you have shafts running inside another.

I know another VERY expensive aspect to the manufacturing cost are fuel nozzles. The amount of misting/atomization required, dual flow, conical spray patterns these suckers is complex and on a TPE run around $6k A PEICE!!! (and there's 8 of them....)


There's got to be a way to attack these issues with a group of smart guys and over come these limitations.