is repackaged from the backend of Space Shuttle Orbiters into a more traditional inline rocket stage. SLS upsized the Shuttle elements — the big fuel tanks are now longer, and there are more ...

When a rocket motor using solid propellant is lit it continues to burn until all of the fuel is consumed ... for a valve which connects to the oxygen tank. There is a nozzle on the outflow ...

It uses a rocket engine that runs on hydrazine fuel ... The Hummingbird bus was also the fuel tank, and it had additional slots for CubeSat components. These components could be used for further ...