Rocket propellants come in two parts, fuel and oxidizer, which work together to keep an engine burning.
Spaceship One burns a material called hydroxy-terminated polybutadiene (HTPB), a common ingredient in tyre rubber, as fuel with nitrous oxide serving as the oxidizer. According to press statements by Scaled, the combination was chosen for Spaceship One after a lengthy study into potential engine systems.
For SpaceShipOne, reaching space takes three things: a pilot, a spacecraft, and enough to propellant to rocket away from Earth.
But the fuel in SpaceShipOne’s tank is about as exotic as the spacecraft’s design. SpaceShipOne, the first non-governmental crewed vehicle to reach space, uses a combination of rubber and nitrous oxide — also known as laughing gas — as it’s powerhouse.
This is a very stable and non-toxic system.
Based in Poway, California, SpaceDev is responsible for refuelling Spaceship One after each flight as well providing crucial elements of its hybrid rocket engine, a cross between traditional liquid and solid rocket motors.
SpaceShipOne was designed by aerospace veteran Burt Rutan and his Mojave, California-based firm Scaled Composites. The craft
represents one of 26 teams vying for the Ansari X Prize competition to privately build a vehicle capable of transporting
three people 62 miles (100 kilometres) above Earth twice in two weeks, with the winner snagging a $10 million purse.
Rubber-based hybrid engines tend to burn at slower rates compared to solid materials, which can affect the final amount of thrust an engine can produce. Some of that burn reduction can be recovered by SpaceDev’s use of pie-like ports for its solid fuel, but additives in the solid fuel could also boost performance.
