I was flicking through the RCDB and found this:

http://rcdb.com/9283.htm

An enclosed 'Four Man Bob' type ride at Brean Leisure Park... Loudoun had one when they closed:

And it's amazing what can be done to one by putting it inside a building:

Something like this would be incredibly good for PWH! I've always said that enclosing Enigma would be a fantastic idea...