 Ralston , who considered the Enterprise ugly and the model hard to shoot , delighted in destroying the ship . Several shots were combined together for the complete destruction sequence ; while Ralston would have preferred to take a mallet to the original $ 150 @,@ 000 model , a variety of cheaper models were used . The first part of the ship to be destroyed was the bridge , a separate miniature with stars added to the background . The shot switches to the Bird of Prey moving away as the top of the saucer burns , where explosions ( filmed upside down to simulate the absence of gravity ) were superimposed over a motion control pass of the ship . The camera cuts to a closeup of the ship 's registration number being eaten away by inner explosions . George created a light Styrofoam model that was dissolved by acetone dripped on the saucer from above . By shooting at less than one frame per second and keeping light off the model , the drips were not visible in the print . Burning steel wool on the inside of the saucer created a glowing ember effect from the ship 's inner decks being destroyed . The saucer explosion was simulated by blowing up a talcum powder @-@ covered plaster dish . Two and four ounce bombs and gasoline were used as pyrotechnics in live action scenes of the bridge being destroyed . <unk> used spring @-@ loaded platforms to launch themselves in the air . 
