The space company of billionaire Microsoft co-founder Paul Allen on Monday unveiled details of medium-lift rockets and a reusable space cargo plane it is developing, injecting more competition into the lucrative launch services market.

With its rockets, Allen's Stratolaunch Systems Corp. is trying to cash in on higher demand in the coming years for vessels that can put satellites into orbit. But his vehicles will have to compete domestically with other space entrepreneurs and industry stalwarts such as Elon Musk's SpaceX and United Launch Alliance — a partnership between Boeing and Lockheed Martin.

Seattle-based Stratolaunch, founded by Allen in 2011, said in a news release its launch vehicles will make satellite deployment "as easy as booking an airline flight," though the first rocket launch is not slated until 2020 at the earliest and the massive airplane it is building to deploy the rockets is still in preflight testing.