The Royal Yacht is not a topic that interests me much usually but when I spotted that a couple of files on the replacement - Project 96 - had been recently opened at The National Archives, Kew, I decided to have a look.
For reference the files are DEFE 23/393 and DEFE 23/397.
Basically, John Major's Conservative government were not willing to fund a new ship and indeed the Chancellor of the Exchequer, Ken Clarke, made a fairly scathing rebuff to the Queen's desire for a new ship, more or less saying the Royal Family had to get with the times. Up to 1993, only 13.8% of Britannia's service life had actually seen the Royal Family aboard. Efforts to interest other government departments in hiring the ship - or a replacement - for arms fairs and the like were similarly abortive. Nobody wanted to fork out cash and there were not enough likely events to make it worthwhile.
A few years prior, DGSS Bath had completed a Concept Design Study in 1989, issuing an Executive Summary in July that year. That is where the painting on p.1 of this thread comes from. The choices were a new-build ship for 1996, a SLEP for Britannia for 20 years more life (1996-2016), or running on Britannia until 2006.
For the new ship, possible wartime roles studied were: MCM Command and Support Ship; Hospital Ship; Casualty Clearance Ship; Forward Medical Support Ship. The latter role was selected as it was easier to rapidly refit in wartime for that role.
The ship was to have a helideck and refuelling facilities for a helicopter up to EH101 size.
Attached are the studies, external appearance choices and the final "Preferred Option". There is also a plan of the ship (the quality is pants because the ink of every page of the report had stuck to its opposite page and it took some careful teasing to open the files, but some of the ink remained on the opposite page.