It’s hard to keep in mind how strange the design of the Enterprise really is. Because it’s very, very strange. Especially at the time, the Enterprise represented a radical design that wasn’t just futuristic, but shockingly outside of what anyone at the time imagined when they imagined a spaceship. It is both industrial and sleek, and somehow looks like both a science vessel and a warship. Even today, it is one of the rare designs that feels both fresh and iconic.
The image above is from the collection of Star Trek blueprints at Cygnus-X1.
Here’s more from Forgotten Trek’s piece on the origin of the Enterprise:
Although Roddenberry knew a lot about his ship, he had never visualized it and consequently made the situation more complicated since he could not give Jefferies a detailed sense of direction. His only guidelines was firm list of what he did not want to see — not any rockets, nor jets nor firestreams. The starship was not to look like a vintage science-fiction rocketship but neither could it resemble anything that would too quickly date the design.
[From lead designer Matt Jeffries] I was concerned about the design of ship that Gene told me would have warp drive. I thought, ‘What the hell is warp drive?’ But I gathered that this ship had to have powerful engines — extremely powerful. To me, that meant that they had to be designed away from the body. Boy, I tried a lot of ideas. I wanted to stay away from the flying saucer shape. The ball or sphere, as you’ll see in some of the sketches, was my idea, but I ended up with the saucer after all….
For the hull, I didn’t really want a saucer because of the term flying saucer and the best pressure vessel of course is a ball, so I started playing with that. But the bulk got in the way and the ball just didn’t work. I flattened it out and I guess we wound up with a saucer! I did it in color on a black matt board, and by the time I finished I thought we really had something.