CAPE CANAVERAL, FL—NASA Administrator Michael Griffin has yet to respond to recent allegations that he used NASA space shuttles on as many as one dozen unauthorized outings to such destinations as New York City, the French Riviera, and his vacation home near Ketchum, ID.

Griffin plays the Pebble Beach course minutes after blasting off from his Idaho vacation home.

A report issued Monday by NASA's Oversight Commission indicates a cumulative 1.8 million miles unaccounted for on the Atlantic, Discovery, and Endeavor shuttles. In addition, shuttle pilot James Kelly reported numerous occasions on which he found the pilot seat "adjusted for someone else."

The report also revealed that radio presets on the shuttles had been changed to receive various talk-radio stations from across the country, and that the cargo bays contained foreign items such as an old pair of sneakers, "aviator"-style sunshades, two empty Big Gulp Los Angeles Dodgers collector cups, and CDs that shuttle astronauts say are not theirs.

Griffin's apparent joyrides came to light last week, when sharp-eyed patrons at Georgia's Augusta National Golf Club spotted Discovery in the club's parking lot. Within hours, NASA employees began coming forward with their own observations.

"Every now and then on a Friday, Mr. Griffin would stop by Launch Complex 39B and say, 'Well, I'm off early today, taking the wife shopping on Fifth Avenue,' and I wouldn't think twice about it," said assistant fuel-cell technician Lawrence Clemmons. "But about half an hour later, the ground would shake, I'd hear this earsplitting roar from the pad, and then the shuttle would fly off."

"Sometimes I'd think, 'Hey, it looked like he had his overnight bag with him,'" continued Clemmons. "Then, on Monday, we'd get an e-mail from Mr. Griffin saying he was running behind, but he was just leaving Edwards Air Force Base and he'd be in soon."

Trajectory-optimization engineer Russ Holcum said he'd long suspected that Griffin "had an in" with the staff in Engineering and Fabrication. Said Holcum: "I figured he knew someone who cut him an extra set of keys or two."

Holcum added: "More than once, I heard him ask the Mission Control guys if they'd mind 'counting him down' on his way out before a long weekend."

In a press conference held Tuesday, NASA spokesperson Arjun Congrove apologized to taxpayers for the billions of dollars expended on the unauthorized missions.

"The shuttle costs an estimated $2 billion per launch, not counting delays and repairs, and for Mr. Griffin to use it to take his wife on luxury shopping trips to Europe is not appropriate," Congrove said. "We apologize to affected personnel at NASA, and to the good people of New York City whose homes were vaporized by Mr. Griffin's several unauthorized launches near LaGuardia Airport."

Griffin may face penalties ranging from dismissal to having his salary garnished for the next 376 years in order to pay for fuel.