When Phase II turned into The Motion Picture, and due to the increased resolution demands of movie photography, Magicam’s model had to be discarded. Andrew Probert, who joined Star Trek as a concept designer for the first feature film, was tasked with redesigning the facility.
Probert told Starlog magazine (Issue #32, March 1980) that his first concept was “to have the dry dock fit the shape of the Enterprise as snugly as possible. This would allow the dry dock to unfold and open — dramatically — to allow the ship to exit,” he said.
Given the variety in shapes and sizes among Starfleet vessels, “I thought it would be a good idea to have an all purpose dry dock that would change shape to conform to these other ships as well,” he said. “In one design, I utilized hinged modular sections.”
This was further simplified and eventually, “the design came back full circle and we ended up with a box shape again” — similar to Minor’s original idea.
The drydock reappeared in Star Trek II: The Wrath of Khan but due to that movie’s limited budget, footage had to be recycled from The Motion Picture.
It also later appeared in Star Trek Generations when Industrial Light & Magic heavily modified it for the scene in which the Enterprise-B is seen leaving drydock in a scene reminiscent of the one in The Motion Picture.
Nick Ottens is the man behind the Forgotten Trek website. The site bills itself as "the largest resource about the production and behind the scenes of Star Trek." Online since 2002, it features concept art, photographs and interviews, some of which has never been published before.. or until now. Be sure to visit the site at Forgotten Trek and keep an eye on StarTrek.com for future pieces from the site's archive.