Something that Jefferies and the other production staff for Star Trek wanted to avoid was to add any unnecessary detail to the ship, like fins attached to the nacelles, which would make it look more like something out of Flash Gordon or Buck Rogers. Jefferies also believed that the hull of the ship should be smooth, with no exposed circuitry or mechanisms, and thought that vital parts of the ship’s inner workings ought to be accessible from inside the ship.
In many ways, the “saucer section” of the Enterprise is one element that harkens back to older-style science-fiction. Flying saucers were a staple in many iconic sci-fi movies of the 1950s, most notably The Day the Earth Stood Still (1951) and Forbidden Planet (1956). The latter movie in particular seems to have been a heavy influence on Star Trek, though one that has seldom been acknowledged. Note, however, that the “laser pistols” used in Star Trek’s original pilot episode, “The Cage”, are actually the same props as used for the hand weapons in Forbidden Planet.
Many of the technical details regarding the ship were deliberately left sketchy. Jefferies had calculated the ship was 947 feet (ca. 288 metres) long, and the crew complement was eventually said to be 430 (though througout early episodes of the show, this number is often quite a bit lower, down to around 200). For faster-than-light travel, the ship relied on a “warp drive”, and it’s never made especially clear exactly what was warped or how it worked, except that you could travel at different “speeds” depending on the “warp factor”.
After Star Trek got cancelled in 1969, re-runs of the show exploded in popularity in the 1970s, eventually leading to the production of an animated series, before pre-production started on a full-blown new TV show, dubbed Star Trek: Phase Two. With the success of Star Wars (1977), plans for the show were scrapped and a decision was made to do a movie instead.
Already for Phase Two, it had been decided to update Matt Jefferies’s original design. For The Motion Picture (1979), Andrew Probert was asked to redesign the vessel more drastically to ensure it would look good in cinemas, and the changes were explained in the movie as the result of a rather extensive refit program following the Enterprise’s return to Earth after its legendary five-year mission. Andy Probert has his own website, which features sketches of work he’s done for Star Trek: The Motion Picture (as well as for The Next Generation).
Taking inspiration from the Phase Two vessel, Probert took the basic elements of Jefferies’s design and updated them. The secondary hull was made more rounded, its belly flowing more naturally to the curve underneath the shuttle bay; the sensor/deflector dish in front was better integrated into the hull. The dish was copper in colour when powered down, a reference to the original vessel’s dish, and would light up bright blue when travelling at warp. When the special effects were handled by Industrial Light & Magic (ILM) from the second movie onwards, this colour difference was dropped, however.
The saucer hull had more details added that were largely hidden on TV screens, like the deflector grid. The saucer was also meant to be able to separate in case of a disaster, and Probert added details to the top of the neck to support this idea. He added outlines on the bottom section of the saucer hull for landing pads that would extend down when the saucer landed on the surface of a planet. Some cross-section drawings of the refit Enterprise depict these landing pads.
The nacelles received a more radical redesign, becoming more flattened. Jefferies had always intended these to be modular anyway. There’s even a line in the episode “The Savage Curtain” that suggests that in an emergency, the nacelles could be jettisoned from the rest of the ship. The straight struts of the original design were also replaced by more aesthetically pleasing struts that were swept back, and made the ship look like it was going somewhere even when it wasn’t.
In The Motion Picture, the model had been given a very intricate paint job, which gave it a pearlescent finish. When ILM took over visual effects duties, they repainted the model in a more simple way, making it appear more flat. Fortunately, the Director’s Cut edition of Star Trek: The Motion Picture has restored the footage and even corrected some mistakes left in the original cut (mainly associated with blue screen effects), so that the paint job of the original model can still be admired.
The original Enterprise design was inspired and has exacted a lasting influence on science fiction. In the original show, all Federation starships used the same model, with different names and registries (like the Constellation in the episode “The Doomsday Machine”, or the starships featured in “The Ultimate Computer”). The Enterprise was even referred to as belonging to the “starship class” (later retconned to Constitution class), as if there was only one type of vessel that deserved that designation.
For The Motion Picture, the design of the Enterprise was updated, and we were also shown different kinds of Starfleet vessels. These included the Reliant in Star Trek II: The Wrath of Khan and the Grissom in Star Trek III: The Search for Spock. Both of these were intended to be smaller, less capable vessels than the Enterprise. Perhaps their operational range was more limited than the Enterprise, which was specifically designed for long-term exploration of deep space.
But The Search for Spock also introduces us to the would-be successor of the Enterprise and other vessels of her class: the USS Excelsior. With a similar mission profile to the Enterprise, the Excelsior has the exact same hull configuration as its predecessor: a saucer attached via a neck section to a secondary hull, from which sprout two struts supporting warp engine nacelles. This basic configuration would be repeated again and again for a variety of Starfleet vessels moving forward, not in the least the USS Enterprise-D from Star Trek: The Next Generation (also designed by Andrew Probert).
For the Starfleet ship designs in the 1990s, the neck section was often removed and the primary hull and secondary hull were more fully integrated, as demonstrated by the design for the USS Voyager in the TV show Star Trek: Voyager and the Enterprise-E in the movie Star Trek: First Contact. Nevertheless, Matt Jefferies’s original design continues to live on in these newer ships.