Peter, thanks for the quick reply - most helpful. I thought that it might be as you described but wanted to double check. No doubt the capzise dislodged it. I will get it sorted for next weekend. Capzise was annoying, especially as I had won the first race beating Ospreys, a RS 400, a Finn and Solos amongst others! After 60 years of sailing, one would of thought that I would know not to let go of the main sheet when hiking out!
This cyclindrical shaped foam bung is located inside the bottom of the top mast to form a semi seal. It stops the top mast filling with water quickly in a capsize but has a small hole in the middle to allow it to drain. I am not sure if they are glued, they seem to stay in with friction and a couple of times I have simply pushed them back in. You could check with RS Sailing Customer Support [email protected] or simply add a little glue if friction is not holding it tight.
On de-rigging after yesterday's races and a capsize (let go of the main sheet whilst bearing away and pulled to boat over to windward!), I found a foam bung falling out of the mast top section. Can anyone let me know where this should be located and how it should be secured in place? I did not take a photo, since I was very cold after the swim and desperately needed to get into the warm car!