Dream ChaserA full-sized structural test article of Sierra Nevada Corporation’s Dream Chaser spacecraft begins “tow tests” at NASA’s Dryden Flight Research Center, verifying the vehicle’s handling on landing gear after touching down. Drop tests and glide tests are scheduled for later in 2013, though all such tests will be completely automated. Sierra Nevada Corporation also provides the main engines for Virgin Galactica’s SpaceShipTwo, and had already built the engines that propelled SpaceShipOne toward its X Prize-winning flight. The Dream Chaser design is based on an unused study vehicle, HL-20, studied by NASA in the 1980s and ’90s, which was in turn based upon a Soviet-era test vehicle called BOR4.