Right, just to clarify a couple of bits.
1. Definitely no scanning.
2. Phone/Tablet could be an option with the right ap but................
3. I've no idea what scale (and therefore what size) the drawings will be, since they're from Thornycroft rather than Admiralty. I assumed that I'd be standing at floor level, holding the camera at somewhere near arms length over a table. I'd therefore prefer a compact type camera, rather than an SLR type. I've still got my big Lumix FZ8 from donkey's years ago and it's the baby Lumix that had a broken shutter opening system. Trying to view the screen on the FZ8 from 2-3ft away, while holding it upright and trying to determine which line I'm looking at on the plan is very iffy!
4. Ideally, therefore, a decent compactish camera with a large screen and a short focal length lens.
Current thinking is the Sony DSCRX100
Cheers
Tony