Egg Jet

Doctor Eggman's Rocket Ship is seen at one time in Sonic the Hedgehog 2 and is possibly created by doctor himself. It is large, grey and red colored space shuttle with four wings each side and five rotors. This rocket ship also is later seen at few comic adaptions.

It is used once, when doctor escapes from Wing Fortress Zone to his space station Death Egg, after he failed to capture and get rid of Sonic at the cockpit room of Wing Fortress Zone. While Sonic manages to miss the rocket ship, Tails returns with repaired Tornado (now with rocket add-on set below) and Sonic and Tails starts chasing Eggman at the sky. After for while Sonic manages to grab from rocket ship's side and keeps hanging on there when rocket ship starts to rise and come close of earth's atmosphere and docks to the Death Egg. The game then progress to Death Egg Zone, the last zone in the game. The rocket ship is not seen since then and gets possibly destroyed during the explosion of Death Egg in the game's ending.

Sonic the Comic
The rocket ship is seen in Fleetway's Sonic the Comic issue 6's story "Attack of the Death Egg", which is seen to take place after storyline adaption of Sonic the Hedgehog 2 in the comic's run. In the story, Sonic the Hedgehog (Sonic the Comic) and Miles "Tails" Prower (Sonic the Comic) used rocket ship (which might be the second model) to get from Wing Fortress Zone to the floating ruins of Death Egg in space. In the comic, it is shown to have four wings as the game originally rest of two at other side are unable to see. As the Death Egg later crashes to the ocean, the rocket ship is completely destroyed.

Archie Comics
Two rocket ships have made appearances in Archie's Sonic the Hedgehog comics, based on appearance from Sonic the Hedgehog 2, even through there are only have two wings above and under the rocket ships. The first one is used by Doctor Eggman himself in issue 229 during his quick escape from Wing Fortress to the Death Egg Mark 2, while Sonic manages to hop on the rocket ship in right time. Later as the rocket ship gets docked at the space station and Eggman with his Death Egg Robot and Sonic starts fighting, Eggman used rocket ship to throw it toward Sonic, as destroying it at same time. While Sonic manages to dodge it, destruction of rocket ships makes place to arena go on fire.

After the GENESIS arc., Eggman is shown to have second rocket ship with different color scheme at storage areas inside of Death Egg Mark 2, which is used by Snively in Sonic Universe's issue 37 to escape from space station. He used it again in the next issue, after his failure of bringing Hope along with him. It is not seen since then as Eggman later caught Snively at Stormtop Village.

Trivia

 * Eggman is known to have more space shuttles inside of his hidden pyramid base during the events of Sonic Adventure 2, as one that Sonic, Tails, Knuckles and Amy used to get to the Space Colony ARK and then possibly used to get back to the earth in the end of the game.
 * While in the game rocket ship shows to have only two wings, others are seen be hidden at the other side and thus unable to see.
 * The rocket ship in Sonic the Comic resembles X-Wing from Star Wars franchise.