Emergencies

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Emergencies

Even after forty-five years of experience, traveling to and living in space is a risky proposition. Both of the world's major spacefaring nations, the United States and Russia, have had close calls and catastrophes.

American Incidents

On the American side, an early emergency in space occurred during the Gemini program. Neil Armstrong, who would later become the first person to set foot on the Moon, had to abort his mission when a stuck thruster sent his spaceship tumbling. Close to losing consciousness, Armstrong fired his maneuvering engines to leave orbit and landed safely in the ocean.

A few years later, the National Aeronautics and Space Administration (NASA) nearly lost the Apollo 13 crew when an oxygen tank exploded, crippling the spacecraft. The mission to the Moon was quickly aborted, and NASA now had a single goal: bring back the crew alive. The module designed to land on the Moon was refashioned into a crude lifeboat as engineers struggled to come up with a way to bring the spacecraft back to Earth. They finally succeeded. Exhausted and freezing, the crew splashed down in the Pacific Ocean on April 17, 1970. NASA later determined that a design flaw had caused the oxygen tank to overheat and explode.

During launch of a space shuttle in 1985, one of the orbiter's three main engines shut down early. Without enough power to lift the spacecraft to its intended orbit, the shuttle pilots carried out an abort-to-orbit procedure and were able to successfully conduct their mission after some hasty replanning by NASA ground control teams. If the shuttle's engine had shut down any earlier, the crew would have been forced to attempt a risky touch-down at one of the shuttle's transatlantic emergency landing sites. In 104 flights of the shuttle, five times engine failures have triggered last-minute launch aborts while the shuttle was still on the ground.

Early the following year, the space shuttle Challenger exploded shortly after liftoff, claiming the lives of seven astronauts in an accident that was not survivable. The shuttle's solid rocket booster, which triggered the explosion, was subsequently redesigned, but the first two minutes of flight, when the boosters are burning and cannot be shut down, still present the most risk to the shuttle and its crew.

Russian Incidents

Russia suffered fatalities during two missions in the early years of human spaceflight. On April 23, 1967, cosmonaut Vladimir Komarov was killed when the parachute of his Soyuz spacecraft failed during the return to Earth. On June 30, 1971, three cosmonauts returning from a twenty-four-day mission on the Salyut 1 space station died during re-entry when the air leaked out of their spaceship through a faulty valve.

Another emergency occurred in 1984, after two Russian cosmonauts climbed aboard their Soyuz spacecraft for a ride to the Salyut 7 space station. Two minutes before liftoff, a fuel line valve failed to close and propellant spilled out and ignited. Flames engulfed the rocket. Ground controllers worked frantically to send radio commands to jettison the crew compartment. An escape rocket fired with just six seconds to spare, carrying the cosmonauts to safety as their launcher exploded on the pad.

During its final years in orbit, the Russian space station Mir suffered a number of mishaps. Among these were two emergencies—occurring within a period of four months—involving fire and depressurization, two of the most dangerous things that can happen to a spacecraft in orbit. In February 1997, a faulty oxygen candle caused a fire to break out. The blaze blocked the route to one of the station's escape vehicles, but quick action by the crew saved the ship. The next Mir crew had an even more hazardous experience in space. An unpiloted Progress resupply craft crashed into Mir, puncturing its hull. The crew had to work frantically to seal off the damaged module.

see also Apollo (volume 3); Challenger (volume 3); Cosmonauts (volume 3); Escape Plans (volume 3); Mir (volume 3).

Irene Brown