Microsoft co-founder Paul Allen and aerospace pioneer Burt Rutan have announced they’re building a giant plane and spaceship to zip people and cargo into orbit.

But unlike traditional rockets and government spaceships, this new commercial spaceship will drop from a high-flying plane instead of blasting off from a launch pad.

Mr Allen and Mr Rutan join a field crowded with Silicon Valley veterans who grew up on Star Trek and now want to fill a void created with the retirement of NASA’s space shuttle. Several companies are competing to develop spacecraft to deliver cargo and astronauts to the International Space Station.

The duo won a prize in 2004 with a spaceship that went into space but not orbit. Their new business model includes tourism and satellites. Their new plane will have a wingspan of 116 metres, longer than a football field.