The Space Plane appears much less rocket-like and more plane-like than standard spacecraft; thus, the name. The fuselage is very thick and bulky. A large portion of the fuselage top is a door to the cargo bay. The Space Plane is different from other spacecraft in that both its launch and landing are horizontal. It also does not require any external or temporary fuel storage; the entire plane goes into and returns from outer space without ejecting any portion of the initial vehicle. The Space Plane's first space mission was meant to last two-weeks; it is unknown for how much longer the spacecraft can operate without maintenance and new supplies. The Space Plane has a crane hand and carried at least one weather satellite on its first mission.
The first astronauts to fly in a Space Plane were Joy Rider, Roger Houston, and Buzz Airfields. Unknown to the humans operating the plane, Chip and Dale were accidentally aboard the Space Plane for its first space flight as well; the rest of the Rescue Rangers arrived during the mission.
As the above astronauts were referred to by Stan Blather as the "first space plane astronauts," the Space Plane is probably a new and experimental model.
The Space Plane appears in Out to Launch.