I expect it's been mentioned elsewhere, but this is an appropriate place to post this...
Here's a link to a rather poor quality (but great sound) 2007 upload of the 1972 Cowes-Torquay-Cowes:
Nearly all Cig 36's - apart from Yellowdrama (Ex-Miss Enfield II) standing on her transom...
This film was made by an oil company (possibly Shell) and I remember it being shown on cine film at end-of-term at Midhurst Grammar in '73. Be good to get hold of a better quality copy...