Buran — first fully autonomous spaceplane orbital flight

At dawn on 15 November 1988, in low cloud and a biting wind off the Kazakh steppe, the Soviet Union launched a space shuttle with nobody inside. The Energia heavy-lift booster, the most powerful rocket the USSR ever successfully flew, lifted the orbiter Buran, meaning Snowstorm, from pad 110/37 at Baikonur, a site rebuilt from the failed N1 Moon rocket program. A first attempt on 29 October had been stopped by the computers 51 seconds before liftoff. This time the count ran to zero, and the white spaceplane vanished into the overcast.

Buran looked like NASA's shuttle but was a different machine underneath. Its main engines rode on Energia rather than the orbiter, freeing the airframe for cargo and letting the rocket lift other heavy payloads on its own. Above all, it could fly itself. After two orbits of Earth, 3 hours and 25 minutes after launch, Buran's computers fired the deorbit burn, flew the searing reentry, shed only a few of its roughly 38,000 thermal tiles, and lined up on the Yubileyniy runway with no human hand on any control.

Touchdown came at about 260 km/h in a crosswind near 60 km/h, within metres of the runway centreline and, by TASS's account, just one second off the predicted time. It was the first fully automatic landing of an orbital spaceplane, something the American shuttle never once performed across 135 crewed flights. Buran rolled to a stop after 1,620 metres and was towed back to its hangar to be prepared for a second flight that never came.

The Soviet Union dissolved three years later, and the program, among the most expensive in Soviet space history, was formally cancelled by Boris Yeltsin in 1993. The flown orbiter sat in storage at Baikonur until 12 May 2002, when its hangar roof collapsed, killing eight workers and crushing the only Buran ever to reach space. Its single flawless flight remains one of spaceflight's great what-ifs, and its autonomous landing prefigured the uncrewed spaceplanes flying today.