WHEN AN EXPLOSION THREATENS THE lives of three astronauts in Apollo 13, Gary Sinise (playing astronaut Ken Mattingly) saves the day by climbing into a simulator in Houston and figuring out a fix. Back in 1970 the reality was not so simple: Mattingly got help from people not portrayed in the film—people like Sam Greenberg. Then a consultant pilot for Grumman Aerospace Corp., which built the lunar module, Greenberg was one of a team that worked in its own simulator on New York's Long Island and cooked up the strategy that provided the crippled capsule with an alternative power source. "These were pretty good friends of ours up in that thing," says Greenberg, now 57. "They were counting on us."
Greenberg ended his part in the adventure with a flourish: He made out a mock bill to the company that built the portion of the spacecraft where the explosion had occurred, charging them $312,421.24 in towing charges. But when the gag invoice wound up on the front page of The New York Times, his bosses were not amused. "I was fired," he recalls. "The PR guy for Grumman said, 'This wasn't cleared, and NASA, our customer, is gonna get all upset.' " Soon after, however, Lou Evans, Grumman's then president, decided, says Greenberg, "that the country needed comic relief—and I got unfired real quick." Today the bill is at the Smithsonian's Air and Space Museum.
Greenberg now runs a computer school near his home in Queens, N.Y., with Lilly, his wife of 14 years. Recently he took her and their son Grant, 7, to see Apollo 13. "It was excellent," he says. "Almost no technical inaccuracies. That amazes me."