I was out on Carsington water last autumn in my mkIV in some very gusty conditions. At some point it all went wrong and she turned over. As I swam around the hull, she turned turtle. I couldn’t get her up by myself and had not fitted any heaving lines. I got the help of the safety boat and with two of us on the hull, we got her up.
I found out quite a lot that day including:
My rear storage locker was not waterproof and filled up with water
The transom flap factory setting was too tight for them to operate.
All of this water made the boat too sluggish for the self-bailers to work.
Since then I have:
Always made sure the storage locker is held tightly and I have fitted a drain plug in it.
Bought some detachable masthead buoyancy for gusty days.
Changed the fitting of the jib sheets from a loop to ones that can now be thrown over the gunwales to the person on the dagger board to be used as a heaving line.
changed the arrangement of the transom flap bungee so that it now has tight and slack settings.
Finally I recently did some capsize practice in calm weather and with my 13 year old. His 8 stone could bring the boat up on his own and we had plenty of time to swim round to the underside of the hull without inversion.
I now feel much more confident in my boat.