Spaceplanes were vehicles that functioned as both aircraft and spacecraft. They first appeared in late 20th century and became popular in the 21st century.
Spaceplanes were a concept that dated back to Nazi Germany in the 1930s. The Nazis were seeking advanced technology. One concept they came up with was the antipodal bomber. The antipodal bomber was to be launched into space by a rocket booster. Once there, it would be propelled by a rocket in orbit around the Earth. It was designed for military reconnaissance and dropping atomic bombs. However, the plans never came to fruition because the Nazis were defeated in World War II. In 1958, after NASA was founded, work began on the X-15 spaceplane. Three X-15s were built and tested. They went through multiple spaceflights until being retired in 1970. The antipodal bomber concept was pursued by NASA with the Boeing X-20 Dyna-Soar in the late 1950s and early 1960s. However, the X-20 was cancelled in 1965 due to budget problems. And besides, satellites and ICBMs were cheaper. The first truly successful spaceplane was the Space Shuttle. Six Space Shuttles were built. They were Enterprise, Columbia, Challenger, Discovery, Atlantis, and Endeavor. Enterprise, which was named after the starship in Star Trek, only did landing tests. In 1986, Challenger exploded at take-off due a failed O-Ring that was temporarily blocked by aluminum. While the Space Shuttle was inactive, the Soviets designed their own spaceplane called the Buran. The Buran only made one unmanned flight in 1988 before the program was cancelled in 1993 by the Russian Federation. The Space Shuttle returned to service in 1989. The Endeavor replaced the Challenger. Then, in 2001, the International Space Station began construction. One idea for the space station was the X-38 Crew Return Vehicle. This was supposed to evacuate the ISS in case of an emergency, but it was cancelled in 2002 due to budget cuts. In 2003, Columbia broke apart while trying to land. Because of the presence of an Israeli astronaut onboard, terrorism was initially suspected, but ruled out. It turned out a piece of foam from the external fuel tank hit the shuttle's wing during take-off. This had happened before, but this time, the foam created a hole which resulted in the explosion. While the Space Shuttle program was inactive again and NASA was being overhauled, Virgin Galactic launched SpaceShipOne on a suborbital spaceflight. It had the same type of launch as the X-15. It took-off from a mothership. The Space Shuttle returned to service in 2005. It was retired in 2011 after 30 years of service. One replacement suggested was the X-33 VentureStar. It used aerospikes to get to space. However, the X-33 was already cancelled by the time the Space Shuttle was retired. Ultimately, what replaced it was the X-37. The first few flights of the X-37 were unmanned. In 2014, the first manned flight of the X-37 took place. It would be in service for years until more advanced spaceplanes came.
There were three kinds of spaceplanes: the rocket spaceplane, the scramjet spaceplane, and many advanced propulsion spacelanes.
(Note: For more info on the use of spaceplanes for passenger travel, see the page on suborbital passenger travel.)
Tech Level: 10
Early commercial spaceplanes, like SpaceShipTwo, were two-stage-to-orbit. The ideal spaceplane would be a single-stage-to-orbit spacecraft (SSTO). In 2019, Reaction Engines Limited conducted the first test flights of the Skylon, the first successful SSTO spacecraft. The Skylon was propelled into space by a Synergic Air-Breathing Engine (SABRE). The SABRE was combination of a precooled air turboramjet and a rocket. It was fuelled by hydrogen. By 2022, the Skylon was going to the International Space Station. The SABRE was the basis for the Scimitar engine used on the LAPCAT A2. Other SSTO spaceplanes used aerospikes. However, all these spaceplanes were replaced with scramjet spaceplanes.
Tech Level: 11
Scramjet engines allowed a plane to fly at hypersonic speeds. After World War III, scramjets were produced that could go at speeds up to Mach 25. This allowed the possibility of scramjet spaceplanes. The spaceplanes were equipped with a turbine-based combined cycle that used a combination of modified turbofans and scramjets that were precooled with hydrogen fuel. The turbofans started the scramjet spaceplanes up. They were also used for propulsion up to Mach 3. At that point, the spaceplane would switch to scramjet mode and accelerate to Mach 25. By that time, sonic boom had been eliminated. Scramjet spaceplanes became commonplace. However, by the late 21st century, more advanced forms of propulsion were being used.
Advanced Propulsion Spaceplanes
Tech Level: 12
In the late 21st century, new more advanced forms of propulsion were becoming commonplace. These were more advanced than conventional rockets and jets. In an era when suborbital and orbital spaceflight, new, more advanced forms of propulsion were necessary for spaceflight. These new more advanced propulsion systems made spaceflight commonplace.