In 1992, Endeavour rescued stranded Intelsat VI; three astronauts captured it by hand, and a new booster sent the satellite to geosynchronous orbit

Some space missions go precisely to plan. Others become one of the most nail-biting rescue stories NASA has ever pulled off. STS-49 was the latter. NASA's official mission archive states that the space shuttle Endeavour launched on its very first flight ever on May 7, 1992, on what became a nine-day mission. It was simple to describe, and brutally hard to do: catch a satellite stranded in the wrong orbit, attach it to a new booster stage, and send it on its way. Three days of failed capture attempts, a record-setting unscheduled spacewalk, and an ending no one could have scripted.

A satellite stuck in the wrong orbit

The troubled satellite was Intelsat VI, which was intended to act as a telecommunications satellite for relaying telephone and television signals from a geosynchronous orbit, a high orbit in which satellites are kept stationary over one particular spot of the Earth. The satellite had been stranded in a low orbit since March 1990 because the rocket intended to push it higher malfunctioned partway through the job, per NASA's mission archive. For two years, a satellite worth tens of millions of dollars sat unusable in orbit. NASA's plan was unusually daring. It planned to send up the astronauts on Endeavour to pluck the satellite directly from its orbit, attach a booster rocket motor to it, and let that motor take it the rest of the way to geosynchronous orbit.

Two spacewalks, two failures

Astronauts Pierre Thuot and Richard Hieb performed the first spacewalk of the mission on May 10, 1992, in an attempt to lock a specially built capture bar onto the satellite with the shuttle's robotic arm. The attempt failed, NASA's mission archive notes, with the satellite beginning to wobble rather than locking into position. A second attempt followed on May 11, using the same method. It failed again. A 1993 paper on the mission by Roelof Schuiling, titled "Endeavour's arduous maiden voyage — STS-49" and published in the journal Spaceflight, captures the mood of a crew now faced with a satellite that had twice refused to cooperate.

Three pairs of hands and one wild idea

With two planned methods exhausted, mission planners tried something unprecedented: sending three astronauts outside at once to steady the satellite by their gloved hands instead of a tool. This happened on May 13, 1992, three days after the first attempt, not nine. In a dedicated account of the event, NASA's own record of the spacewalk states that Thuot, Hieb, and fellow astronaut Thomas Akers made an unscheduled but successful hand capture, while Commander Daniel Brandenstein carefully guided the orbiter to within a few feet of the satellite. It was the first three-person spacewalk in history and lasted 8 hours and 29 minutes. A fourth spacewalk occurred on May 14, with astronauts Kathryn Thornton and Thomas Akers testing space station assembly techniques as part of a separate experiment unrelated to the satellite rescue itself.

A new engine and a happy ending

When the satellite was finally secured, the crew attached it to a new perigee kick motor, which is basically a new engine bolted onto an old satellite. Endeavour returned Intelsat VI to space; its new motor fired as planned, and the satellite climbed to the geosynchronous orbit it was supposed to reach two years earlier. The satellite was then successfully redeployed for operational use after reaching the target orbit, NASA's mission archive confirms.

Why this 1992 rescue still matters today

This flight was notable for several reasons. NASA recorded several firsts from the mission: it was Endeavour's first flight, the first shuttle flight to conduct four spacewalks, the first shuttle mission to require three separate rendezvous with an orbiting spacecraft, and the first time a live rocket motor was attached to a satellite already in orbit. That mission also marked the first shuttle landing to use a drag chute, when Endeavour touched down at Edwards Air Force Base. More than 30 years later, STS-49 remains a reminder that even the most carefully planned space missions sometimes need improvisation. The tools failed twice, and it wasn't better engineering that saved the day; it was three astronauts together, willing to reach out and hold on.