I'm not familiar with an Airstream dinette except from floor plans.
I had an Aristocrat that had a dinette and it made a full size bed. The table
top laid on ledges on the seat boxes and the cushions were proportioned to
lay down into a full size mattress. If the cushions had been good sprung ones
instead of foam blocking it would have been more comfortable. It wasn't bad,
though, and better than the convertabed sofas I have slept (sort of) on.
Al Grayson