Space 'taxis' could cut the cost of spaceflight

IN 1982, an Australian spy plane snapped photographs of a miniature space shuttle being fished out of the Indian Ocean by a Soviet ship. The craft turned out to be a BOR-4, which the Russians were testing as part of their short-lived space shuttle programme.

So intrigued was NASA by the photographs that it developed its own mini-shuttle, the HL-20 – intended as a possible astronaut rescue vehicle until the project’s funding was cut in the early 1990s.

But a modified version of the HL-20, called Dream Chaser, could yet reach the final frontier, if its developer,…