BOR4: the mini-shuttle that almost was

BOR4The Soviet Union launches a scaled-down test model of a compact space shuttle design into orbit, part of an ultimately abandoned study of a vehicle design called Spiral. The BOR4 structural test article is photographed being recovered from the Indian Ocean by the Australian government, revealing the design to the western world for the first time. NASA begins a study of the BOR4 lifting body design, finding that it has a stable flight profile and unusually good reentry and landing characteristics, and though NASA’s version of the vehicle, HL20, is later mooted as a shuttle replacement, both countries’ space agencies pass on the design, which will later be revived by Sierra Nevada Corporation as the Dream Chaser. BOR4 is launched three more times through 1984, at which point the Soviets instead press ahead with development of Buran, a near-exact copy of the American Space Shuttle.