Reusable rocket
A rocket that is recovered after launch, serviced and flown again. Not throwing the vehicle away brings down the cost of launch.
Most of the cost of a rocket is the vehicle, not the fuel. The Space Shuttle, which first flew in 1981, was meant to be reusable, but each flight required such extensive inspection and maintenance that it ended up costing more. Reuse pays only when the returned vehicle can fly again with hardly any work.
In 2015 SpaceX's Falcon 9 slowed its first stage with its engines and landed it upright. By the reckoning of NASA's Harry Jones, the cost of carrying one kilogram to low Earth orbit fell from tens of thousands of dollars on the Shuttle to about $2,700 on Falcon 9, roughly a twentieth[1]. Reuse of the whole vehicle, second stage included, is now being attempted.
Related terms
- Multistage rocketA rocket that sheds the parts whose fuel is spent as it flies. With that weight gone, the remaining stages accelerate faster.
- Convex optimizationThe class of problems of finding the best answer that have no false answers to get stuck on, so the true best can always be reached quickly.
- Liquid-propellant rocketA rocket that burns liquid fuel and oxidiser fed into a combustion chamber. The burn can be throttled, stopped and restarted.