Brenner,

It means taking a stock APC and laminating it with carbon fiber cloth. Wayne Ulery has been doing this (and other modifications to props) for a number of years. Last year, I started experimenting with CF on some of the APC-E props. At relatively low RPMS, the stock prop runs the same as a prop with CF added. At higher RPMs, the stock prop starts to flex and this increases noise, current draw, and reduces RPM. At that point, adding CF to stiffen the prop results in minimal to substantial performance increases (the amount depends on just how much flex was occuring).

Regards,

Dave