The Glitch & the Gemini

It began as one of those flawless launches that the U.S. public has come to take for granted in the eighth year of the space age. Weather was ideal; the complex countdown proceeded without a hitch. Precisely on schedule, the reliable Atlas booster roared up from Cape Kennedy and out over the Atlantic carrying an unmanned Agena rocket as its payload. Astronauts Walter Schirra and Tom Stafford watched the action on TV as they waited for their own scheduled liftoff, 1 hr. 41 min. later, in Gemini 6, the capsule in which they would make the first attempt at rendezvous and linkup in space. Then, six minutes later, the Agena target vehicle mysteriously disintegrated. The whole mission was scrubbed, and from Houston to the Cape, U.S. spacemen began to search their telemetered data for some sign of what had gone wrong.

No Joy. It was easier to record what had gone right. Agena and Atlas had separated on schedule, and a secondary engine had fired to stabilize the Agena and ensure that the fuel was positioned correctly in the tanks. Then the primary engine, capable of 16,000 lbs. of thrust, was supposed to kick Agena into a 185-mile-high orbit around the earth. But already ground control was receiving the first ominous signals. In the tank that stored the rocket's oxidizer, pressure was racing up above the red danger line.

Then, 143 miles high and 541.9 miles downrange over the Atlantic, the Agena suddenly went silent. At the Houston control center, flight directors hunted desperately for their missing spacecraft, still hoping that there might be something in orbit for a Gemini rendezvous. But after a futile radar hunt, a technician at the Carnavon tracking station in Australia announced the end by moaning "No joy, no joy."

Quick Critics. In Houston, Flight Director Chris Kraft, NASA Manned Spacecraft Center Director Robert Gilruth and his deputy George Low glumly surveyed the failure of a mission. It may be weeks before the experts can identify the "glitch," the space-age devil that caused the trouble. And if it turns out to be a major design failure in the Agena, the Gemini program is in deep trouble. Five of the next six Gemini missions involve rendezvous and docking exercises with an Agena target.

Critics were quick to point out that the Agena had been extensively modified for its docking mission, and many of its components had never been tested in space flight. NASA's calculated risk, it was suggested, had resulted in catastrophe. Test flights, however, would have been both costly and timeconsuming, and the Agena's previous record of reliability made them seem unduly wasteful. An identical twin of the lost rocket had been extensively checked on the ground, fired in a test stand, put in a vacuum chamber to simulate operating altitudes, started and restarted until all the glitches seemed gone. The fact is, says one of the country's top rocket-motor experts, that "sometimes these birds just flop—even though the chances are something like 9 in 10 that it won't happen."