My 82 Cherubini came with a Qm30, with a fixed prop. manual says put in neutral. I have a max prop. and when I shift to neutral the shaft does not rotate. so either way there is no rotation.
The bulletin does call out shaft brakes and folding / feathering props as alternatives if you prefer not to keep the prop freewheeling. As for drag - several tests have shown that freewheeling is less drag. See, for example: http://forums.sailboatowners.com/index.php?threads/fixed-vs-free-wheeling-prop-updated.107118/Maybe a shaft brake is the answer. A spinning prop creates wear on cutlass bearings and stuffing boxes etc. Also more drag, I think.
Hi DavidThe bulletin does call out shaft brakes and folding / feathering props as alternatives if you prefer not to keep the prop freewheeling. As for drag - several tests have shown that freewheeling is less drag. See, for example: http://forums.sailboatowners.com/index.php?threads/fixed-vs-free-wheeling-prop-updated.107118/
http://www.yachtingmonthly.com/gear/lock-prop-let-spin-29526
http://www.flexofold.com/upload_dir/docs/Test_YachtingMonthly_low.pdf