I am trying to ascertain what statutory equipment is required on a UK
flagged yacht when deep ocean sailing. So far I have only found 5 UK
Parliament Statutory Instruments that affect a 15m pleasure vessel -
SOLAS Ch 5 under SI 2002 No 1473, Lifesaving Appliances SI 1999 No
2721, Firefighting Appliances under SI 1998 No 1998 No 1011, Collision
Regs under SI 1996 No 75 and Pollution under SI 1998 No 1377. Failure
to comply with these regs could result in prosecution. If there any
other statutory requirements for equipment, then I'd be interested to
know.

The statutory requirements do not even include a radio.

There are of course long lists of recommended equipment, which is
another matter, and an insurance company may take a dim view if various
items are not onboard.

Thanks.