Anti-Capsize Systems.

[noelex 77]

I have been experimenting with a GPS compass and one of the surprising features is the speed and accuracy of the angle of heel measurement. It would seem viable to rig this to an electronically controlled clutch to release the sheets.

It would obviously need some practical experimentation, but I think this would be fast enough. The load needed to release a clutch/jammer is not very high so the release mechanism need not be difficult to manufacture. GPS compasses are not enormously expensive these days and have a lot of other useful attributes. I suspect the heel angle calculation is primarily from the multitude of gyros that are part of a GPS compass rather than just the GPS signal, so a device that was just constructed for a heel angle display could probably be made better and cheaper.

Rapid changes in wind strength/direction is a concern for a short handed crew sailing a cat. A system like this if it could be made to work would add some peace of mind, especially when the crew were a long away from the sheet controls such as when using the head.

[Seabeau]

There is an excellent article concerning anti-Capsize systems, especially concerning multihulls in this months issue of Practical Sailor.

[Nicocrispi]

Originally Posted by noelex 77

I have been experimenting with a GPS compass and one of the surprising features is the speed and accuracy of the angle of heel measurement. It would seem viable to rig this to an electronically controlled clutch to release the sheets....

Interesting. I once asked my son to design a system where the sheet release can be actuated whenever a coupled digital anemometer exceeds a certain wind speed. He designed it and talked to Raytheon about a potential license but they eventually said that their sales projections wouldn't justify the prototyping and validating.

I like the French systems and I hope that they will be better and cheaper in two years when I expect my boat to be launched.

[TonyBe]

Originally Posted by Cotemar

OR you can Spend $40,000 and have a COMPLEX unproven Anti-Capsize Systems do it for you.

I think that perhaps you are thinking of one of the bespoke systems designed for superyachts.

The basic system for cats up to 50', called "UpsideUp Easy" costs around €1,200.

As to them being unproven, I don't believe that there have been any reports of the system not working (unless anyone knows otherwise?).

There was also a recent article about the latest HH66 that was launched (hull no. 5 I think) and the designer said that, as part of the sea trials, they were deliberately trying to fly a hull but they just could not do it. They then realised that they had the UpsideUp system on so they turned it off and were then able to fly a hull without any problem.

Capsizing may be an issue for the likes of Gunboats or Outremer 5X etc when they are being driven hard, but for most cruising cats the issue is not so much capsizing as damage to the mast and rigging caused by excessive loads before they get anywhere near to even flying a hull, never mind capsizing.

I would suggest that a typically loaded cruising Lagoon or FP is much more likely to lose its mast or rigging before it ever flys a hull.


Is it worthwhile installing? Well, if you have a typical cruising cat and are the sort of person who reefs rather late instead of early and are concerned about damage to your rigging then I would say it is probably worth considering.

If you have something like an Outremer 5X then this really is just a bit of cheap, extra insurance and why wouldn't you go for it?