We used a similar setup a couple of years later for the film Crimson Tide to show the Russian Akula sub going through explosive decompression. For that model we used 6 much larger vacuum bell jars, placed end to end in the 18 foot long model submarine. The hull of that Akula model was made from sheet lead. When the bell jars were shattered by the charges in rapid succession from back to front, they imploded, sucking in the lead hull. Unfortunately the camera angle used in the cut of the film didn't show off the shot the best, but there is a very good behind the scenes bit that does on the DVD extras.
Those were the good ol' days, none of the mamby pamby CG stuff. We really got our feet wet back then. Literally!