Frank Cepollina takes repair calls to new heights.
- By Robert Zimmerman
- Air & Space magazine, May 2010
(Page 3 of 5)
Amazingly, NASA managers were not interested in the idea at first. Goddard’s focus was on reducing the cost of satellites and increasing their reliability, and there was no money for servicing missions. Then Solar Max failed. The mission had been launched in 1980 as the first of Cepollina’s modular spacecraft; its job was to observe the sun at the peak of its 11-year cycle, and it had been designed to be retrieved by the shuttle.
Only nine months after the satellite was launched, however, three fuses in its attitude control system module failed. Shortly after that, a coronagraph-polarimeter designed to study the sun’s corona suffered an electrical failure. Though the spacecraft had been built with plug-and-play subsystems, NASA management was uninterested in a repair mission. Some feared it would be a waste of money: What if something else on the spacecraft failed soon after the repair? More importantly, there was no money for a fix; paying to repair Solar Max would have delayed or canceled some other project.
To Cepollina, not doing the repair when it was feasible was unacceptable. He began calling reporters, letting them know that the spacecraft’s repair would be a trivial matter. “He was not beyond going to the press,” remembers Rothenberg. “His ideas would be in the papers before anybody in the NASA management chain even had a chance to approve it.”
The outspokenness got him in trouble. “I can’t tell you the number of times his boss, including me, had him on the carpet, telling him to cease and desist,” adds Rothenberg. “He’d walk out of the room dejected, go home to sleep it off, and then return the next day as if he never heard what his boss said.”
Cepollina knew that if he could marshal public and Congressional opinion without causing harm to his superiors, they would eventually go along. Sure enough, NASA headquarters finally approved the repair mission, with Cepollina in charge.
He remembers it as the most terrifying time in his career. The future of in-space servicing, an idea he had promoted for years, hinged on this one flight. And immediately after space shuttle Challenger rendezvoused with Solar Max on April 8, 1984, the plan started to unravel. Astronaut George “Pinky” Nelson donned a Manned Maneuvering Unit backpack and flew from the shuttle to the satellite, but was unable to capture Solar Max with a specially designed piece of equipment (it turned out later that a grommet on the satellite—which didn’t appear in blueprints—blocked the docking mechanism).
After three attempts, Nelson succeeded only in setting the spacecraft tumbling. It took a series of hastily prepared software uploads by the ground, combined with a bit of luck when the nearly dead spacecraft drifted into sunlight just long enough—10 minutes—to charge its batteries, to stabilize the spacecraft so that the Challenger astronauts could grab it with the shuttle’s robot arm and haul it into the cargo bay. Finally back on script, Nelson and crewmate James “Ox” Van Hoften breezed through the repair. “They had to do two days’ worth of stuff in one day, and they finished it all,” remembers Barbara Scott, who was the payload operations engineer for the repair mission and is now the Hubble Flight Software manager at Goddard. As a result, Solar Max operated for another five years, recording more than 12,500 solar flares. Just as significantly, the failed attitude control module was returned to the ground, refurbished, and installed on another spacecraft, the Upper Atmosphere Research Satellite. That spacecraft was launched in 1991, and operated in orbit for 14 years. “Second-hand Rose,” Cepollina quips.
The Solar Max repair gave NASA confidence in its plan to send astronauts to Hubble periodically to replace cameras and other scientific instruments with more capable ones, just like an observatory on the ground. For the first Hubble service mission—which also corrected the telescope’s out-of-focus mirror—the Goddard team came up with procedures for replacing three failed gyroscopes, two electronic control units, and eight fuses.