White House chief of staff John Sununu, under fire for his extensive use of government planes, twice flew to Boston for dental appointments on a military jet costing $3,945 an hour to operate.

Sununu also got a hop on a military plane to visit his parents in Florida and again to attend a New Jersey football game and farewell party for outgoing Gov. Tom Kean.Trying to quell the flap over Sununu's travels, the White House released documents Tuesday itemizing 77 trips by Sununu from the spring of 1989 until last weekend.

Sununu listed most of his travel on military planes, including visits to Colorado ski resorts and repeated trips to his home state of New Hampshire, as official business. He said 24 trips were for political business, 49 were for official reasons and only four were personal - the two dental visits and the New Jersey and Florida trips.

Sununu's travels cost taxpayers an estimated half million dollars, based on the hourly operating cost of the 12-passenger C-20 corporate-style jet he usually flies.

Sununu and the Republican Party reimbursed the government $47,044 for his travels, in line with a government policy requiring payment of the regular commercial fare plus $1 for private trips.

Democrats have instituted a congressional audit of Sununu's travel expenses. However, responding to the release of his travel itinerary, they acknowledged he has not broken any rules.

Rep. Robert E. Wise Jr., D-W.Va., chairman of a House Government Operations subcommittee, said Sununu "probably followed the regulations. The question is whether this is the mode of travel he ought to become accustomed to for personal reasons."

However, Rep. Bob McEwen, R-Ohio, said Sununu was the victim of "the cheap shot of the week."

Addressing the House, McEwen said "My question, very simply, is this: If the person responsible for the most important office in the land does not have access to government planes, exactly who are the government planes for?"

Sununu repaid the government $900 for his two trips to the dentist in Boston. He paid $200 for the personal travel in New Jersey and $167 for a hop from Key Largo to West Palm Beach to visit his parents.

Sununu did not talk with reporters about his travel, and White House officials who discussed it did so only on condition of anonymity. Explaining his trip to a Boston dentist, one official said "That's where he started the work. You want the same dentist to finish the work."

Sununu and Bush's national security adviser, Brent Scowcroft, are the only White House staff members authorized to travel on Air Force planes.

In contrast to Sununu, Scowcroft took government aircraft on 23 trips between March 7, 1989, and Oct. 26, 1990. All of the trips were listed as official except one - a ski vacation with his daughter to Utah on March 10, 1990. He reimbursed the government $1,052, the White House said.

The travel policy was adopted in August 1987 during the Reagan administration to ensure that the people in the two jobs could always be contacted and to protect them from the threat of hijacking.

The 1987 White House guidelines said that when traveling on vacation or private business, the officials "should evaluate the use of military air transportation on the basis of appearance or impropriety."

Defending Sununu's trips, White House spokesman Marlin Fitzwater said Sununu and Scowcroft needed military planes equipped with sophisticated communications devices that prevent conversations from being overheard.