Carbon fiber driveshaft

sireland67 said
Modern helicopters run a carbon fiber driveshaft to the tail rotors.
But they are about 200K each.
Fiber density and resin system is the key, plus they are autoclave cured.

Helo's used to use AL tail rotor shafts, it's where the idea came from to use them in cars years ago, 1st in race cars and then the factory caught on.

And it is very important where that CF tube is made and how. . .