To nobody’s surprise, George Bush finally clipped the wings of his high-flying chief of staff last week. From now on, John Sununu will have strictly limited privileges on VIP military aircraft, and he’ll have to clear all such flights with the White House counsel. But the flap over Air Sununu has metastasized, threatening new embarrassments in the Bush cabinet. “Newsweek’ has learned that Veterans Affairs Secretary Edward J. Derwinski and his deputy, Anthony J. Principi, have billed the government for dozens of commercial flights to their hometowns. And a federal official confirmed that the Justice Department is investigating accusations that the former education secretary Lauro Cavazos had criminally abused federal travel rules.

Under other circumstances, Derwinski and Principi might only have raised a few eyebrows with their bills. Both concede that they enjoy going home, and have gratefully accepted invitations to official appearances in Chicago (Derwinski’s base) and southern California (where Principi’s wife and three children still live). Both flew mainly coach, at a total cost that was less than a tenth of Sununu’s $600,000 bill. But according to Veterans Affairs documents, Derwinski had managed to log 27 visits to Chicago in 26 months, while Principi conveniently found 14 occasions to visit San Diego and made roughly 20 more flights to Western cities where he either met his wife or paid his own final leg home. “Chicago is where my heart is,” Derwinski told “Newsweek.’ “I have a soft spot and tend to accept those engagements more readily.” But he insisted all the trips were legitimate, and Principi said the same. “I try to be careful and I try not to abuse it,” he said.

Cavazos was fired just last December, ostensibly because of a weak job performance. Even at the time, there were rumors about his travel bills. But New York Newsday reported (and “Newsweek’ has confirmed) that Justice Department investigators are looking into stories that Cavazos violated federal rules by using frequent-flier bonuses on commercial flights to pay his wife’s fare when she flew with him. The Justice Department refused to discuss the case, and Cavazos couldn’t be found.

The major embarrassment, however, was still Sununu’s imperial use of Air Force planes for personal, political and dubiously official trips. As it turned out, he had ample cause to pinch pennies: with eight children, and with mortgage payments, real-estate taxes and college bills totaling at least $90,000 a year, Sununu and his wife, Nancy, were struggling to get by on their combined salaries of $182,500. As The Washington Post quoted their banker, they couldn’t make ends meet without her job as a GOP fund raiser; they have been late with several tax payments.

But the new White House rules put Sununu’s travels under strict scrutiny, and the dictatorial chief of staff will have to beg permission for each flight from his subordinate, counsel C. Boyden Gray. All told, said a White House aide, Sununu “got off easy, but he also got the message.” The message: George Bush’s patience has worn thin, and Sununu has little margin for error left.