Rotary rockets. Computer illustration of two Roton rotary rockets in orbit. One (right) has deployed a satellite (lower right). Roton is a revolution- ary design: far lighter than normal rockets due to its unique engine. Unlike normal rockets, it does not have a single combustion chamber with weighty pumps feeding in fuel. Instead it has a 7 metre wide rotating disc with 96 small combustion cham- bers around it, into which fuel is thrown by the force of the disc's rotation. The craft has rotor blades on its nose (not seen here) which are used to stabilise and slow its descent in the manner of a helicopter. Roton has been designed by the Rotary Rocket Company, based in California, USA.