I'm pleased to say I've travelled on the SRN2 and a couple of SRN5s.
Westland used the SRN2 on the Southsea-Ryde service for a short while in the early 60s at the same time as using the much smaller SRN5s on the same route. The SRN2 was hugely impressive and towered over us even when landed on the gravel beach, and my then wife, then former Mrs_PR19 :), did a film star-like 'turn and wave' at the top of the gangway even though there was no-one seeing us off! The SRN2 was fitted with some very bulbous skirts in service then which I think were the 'fingerless' type and so they lay in canvas heaps alongside the hull and looked most untidy, but I think they had fingers added later on.
The SRN5 was a tiny thing which we boarded over a fold down ramp right in the bow and which actually incorporated part of the windscreen! The SRN5s didn't last very long on that route and were soon replaced by the much larger SRN6s which were just lengthened versions of the SRN5s but had a more versatile control system. On a couple of the SRN5 trips I made the Captain/Pilot had the devil of a job getting the craft lined up with the beach and had to turn away and have another go. I think the SRN6s used Harrier-like ports on the bow to improve their turning ability, and I can't remember any trips on an SRN6 being anything but smooth and straightforward.
They still use hovercraft on the route to this day, indeed the current Mrs_PR19 and I travelled on them earlier this year, but the current craft use DIESEL engines for goodness sake, and almost seem throwbacks, especially after the magnificent SRN2.
[Later] I just looked at JCF's drawings again and noticed the torpedo tube on the SRN3! I've never heard or seen of that idea before but I guess it made a lot of sense. I saw the SRN3 'do it's thing' at an IHTU Hoverday demo at Lee-on-Solent and it was SERIOUSLY impressive! There are some good photos of it in action here :-
http://www.jameshovercraft.co.uk/hover/srn3/srn3.phpIn fact that whole site is a very useful source of hovercraft information.