Luiz,

I remember we had another thread on this topic. Something that I found interesting in the article linked to by Tornado in this thread ( Farrier Capsize article ) is that instead of using any kind of water sensor, they were looking at using a pitch sensor such that if the boat exceeded 90 degrees, it would deploy the mast bag.

I would also imagine that the bag could be made to fit in a recess in the top of the mast somehow.

Jake,

Thanks for the link!

Some remarks:

1) An "airbag" is not a good idea because it is activated by explosives. A small gas cilynder is better and safer. That's why I prefer to call it "automatically inflated masthead float".

2) If we use a fixed device in the top of the mast, then one can not take it out for races. This makes maintenance more difficult. In my case, this means I would not give it any... so I prefer to have it attached to the mainsail, with freedom to use it or not.

3) The mast top is subjected to high accelerations when the boat moves in waves. A sensor activated by the angle would require LOTS of damping to avoid accidental activation. It is feasible, but not simple, nor imediately available in the market (I think).

4) If you agree that attaching the device to the head of the mainsail is the best choice, then activating by pitch angle doesn't work, because the sensor may (will) be activated when the sail is floggind, being hoisted or lowered.

BUT if the only device available was a fixed one, activated by explosives and using a pitch angle sensor - I'd use it anyway.

If a water activated, gas filled, masthead float that can be attached to the head of the mainsail ever becomes available - I'd prefer that.

Cheers,

I think the article had intended that a small CO2 bottle would be housed somewhere near the base of the mast as well as the pitch sensor. It should be reliable located down low as opposed to the top of the mast. The valve for the air could also be kept down low.

I wouldn't want to put explosives anywhere near a carbon fiber mast!

Jake