This was posted in a draft ruleset for the F12 class


I was wondering about what a "sealed air compartment" really is, how you build it, and how you drain it if/when water condensates inside it? Via a drain plug, or is a hatch good enough?

I did not want to muddy their rules discussion with a technical question, so I choose to post the question here in the homebuilders forum.

Rolf,

this rule is in both the F16 and F18 rules in some form or another. One option I've seen used is a water tight bulkhead at the forward beam. with a screw in (transom style) bung in the base. This creates a watertight compartment forward of the beam and the bung is released through an inspection port when the boat is on shore. As you're probably aware most people get around this rule using foam.

All those years ago when I started building my boat. I had foam cut out at every second bulk head. Now I have used the bung method, but I have also put an inspection port in the bulkhead as well.
Just something else to forget to put in.

But it should work. Just hope I don't get T Boned on the bulk head.

What about some sort of airbag inside the bulkhead? This would preserve the floatation integrity in a "t-bone" unless the float, well, floats away.

With the bung method, how do you keep the pressure changes from affecting the integrity? If you forget to open it up on the beach between races, will it cause issues or is the bulkhead strong enough?

With that wording, only a single compartment is required, which doesn't provide the level is safety that I believe is intended.

Preferred wording should state something along the lines of requiring two compartments of atleast 30 litres each, which I believe is the intent.

Something like...

1.5.2 Each hull shall carry atleast two compartments of alteast 30 liters of flotation each. The hull may be divided into two suitable compartments with a watertight bulkhead or a single compartment hull may be fitted with solid closed cell foam, solid blocks of compacted foam granulate or air bags of 30 litres volume each suitable attached to the hull.

A bit wordy but hopefully less ambiguous.

oops, probably wrong location for this.

I sometimes carry an air bag as crew.

Woops hope she dosn't read this.