We have been using Brunton Autoprops for about 12 years, I guess, and put massive motoring hours on the one on the old boat (I guess around 5,000 hours of motoring on the old one) without ever changing any bearings, just grease them up good every year or two. We've never had the slightest problem (other than I just burned up the one on the new boat with electrolysis
, but that's not the prop's fault). Some other people have had various kinds of trouble so I can only tell about my own experience and you have to make up your mind. We have not found them particularly demanding of maintenance
. Maybe we've been lucky. I do have the impression that the the Autoprop has to be very exactly and very successfully designed for your particular boat, and maybe some kinds of drive shafts and underbodies are better and some are less suitable for the peculiarities of the Autoprop. But they worked flawlessly in both our old boat (semi-long keel) and new boat (high performance bulb keel), despite very different design. Butter-smooth, silent, no vibration at all, and that great feeling which I can only describe as saying -- you always feel like you're in just the "right gear".
In any case, I think it's pretty clear that motoring performance of the Autoprops is superior to anything else, and I personally find the "automatic transmission" like variable pitch
, which is very different from all other props, is really extremely useful, optimizing thrust and revs under all conditions, saving you beaucoup fuel
, wear & tear. Some people don't quite understand that the design prevents lugging the engine
, so you can just loaf along at a relaxed RPM
with every bit of power of the engine
being tranformed into motion. We love them. But maybe we've been lucky. Your results may vary.
Oh, and sailing performance is just about the worst of all the moving-blade propellors. Quite a lot of drag, compared to folding props, although it's still a fraction of that of fixed props.