Spaceballs: The Wiki

This is the back of the spacecraft.

Dark helmet and Sandurz

Spaceball I (also Spaceball One) was a spacecraft owned by Planet Spaceball and commanded by Dark Helmet. It was a spoof of Darth Vader's personal Star Destroyer, The Executor, as well as the Death Star (although, ironically, the overall profile of the ship resembled the Rebel Blockade Runner). It was extremely long. (After the prologue of Spaceballs finished, it took almost two minutes for the camera to finish panning across Spaceball I.) In addition to some of the rooms usually found in a spacecraft, it held a shopping mall, a three-ring circus, and a zoo. Hundreds of people were on its crew. It had the ability to transform into Mega Maid, a transformer. After much use, Dark Helmet accidentally pressed the Self Destruct Button in the climax of a duel with Lone Starr due to his Schwartz backfiring on him, so it exploded. Most of the crew escaped the explosion. However, President Skroob, Dark Helmet, and Colonel Sandurz did not (the former due to a bear taking the last spot of the final escape pod at the last second). They ended up crashing on the Planet of the Apes.

Spaceball I was eleven kilometers or 6.8 miles in length.