BANGOR – More domestic passengers are flying through Bangor International Airport than ever before, according to figures released Thursday.

Roughly 480,600 passengers flew in and out of the airport in 2005, beating by 5 percent the previous record set in 1998. The number represents a 6 percent increase over 2004.

The new figure is the highest since the airport began documenting domestic passenger numbers 10 years ago. It includes only scheduled flights. Diversions and military flights, even those contracted on private carriers, are not included.

Much of the growth can be attributed to the emergence of regional jet service that offers more destinations and competitive airfares, Airport Director Rebecca Hupp said Thursday.

“The regional jet allows the Bangor market access to a number of more hubs, and it also allows greater frequency,” she said. “The core of Bangor residents are using [BIA].”

All of the airport’s flights are now on regional jets, which are smaller than traditional Boeings or Airbuses but can carry more passengers than turboprops. The regional jets, which typically carry 50 to 70 people, carry passengers to major hubs for connecting flights on larger aircraft.

The last scheduled turboprop flight out of BIA was a Continental Express flight to Albany, N.Y., in spring 2005, Hupp said.

The international flights that were once the airport’s bread and butter have gone by the wayside, peaking in 1991 with 911,999 passengers. The subsequent domestic turboprop service proved unpopular with consumers, dropping passenger numbers to a low between 1999 and 2001.

The figures climbed back up with the institution of today’s regional jet service, Hupp said. Also contributing to the airport’s growth is a greater number of local people flying out of Bangor and more passengers coming to Maine to visit, she said.

“I think we’re regaining market share in our own market,” she said.

Business and leisure travel out of BIA is about evenly split, Hupp said.

Though some people complain about higher fares out of BIA, the airport continues to succeed, City Councilor Peter D’Errico said Thursday.

“In spite of that, it’s still growing,” he said.

D’Errico was the airport’s second director and its longest-serving one, heading the facility from 1970 to 1991. Not all passengers flying out of BIA are entirely happy with the service, according to some local travel agencies.

Though some clients at Bangor Travel Services are loyal to BIA and will pay higher fares, many complain about the prices, Diane Bean, a certified travel consultant at the agency, said Thursday.

Flight cuts made at BIA in December by Delta and American Airlines have significantly affected availability, particularly for clients planning Easter and April vacations, Bean said.

“While we still have a lot of people who want to fly in and out of Bangor, our inventory has been cut,” she said. “All of a sudden, wham, they’re taking our service away.”

The flight cancellations have lead to unexpected and frustrating itinerary changes for clients, Joyce Landry of Cruises Inc. in Medway said Thursday. The company handles numerous flight arrangements for cruises and resorts.

“I’m afraid people will start leaving Bangor because of it and pay a little more go to Portland or Manchester [N.H.] or one of those places,” Landry said, adding that rising gas prices have deterred some of that behavior.

The instability of the airline industry has affected BIA, though Continental has added a nonstop flight to Newark, N.J., out of Bangor, Hupp said.

“It’s not a reflection of our market, it’s a reflection of the industry,” she said.

Passengers lost a low-cost carrier option this month out of southern Maine when Independence Air ceased service to Portland International Jetport. The jetport, however, did break its previous passenger record, with 1,454,027 fliers in 2005.

Along with industry uncertainty, D’Errico said he worried about the impending decline of troop and transient flights into Bangor. They affect landing and ground handling fees, as well as fuel prices, he said.

“My concern is eventually as the war situation quiets down, this kind of business will decrease, and how will we replace it?” D’Errico said.

The City Council is pursuing a marketing study to answer that question, he said.

Despite its challenges, BIA continues to grow. Travel is up as people who have put off trips in recent years finally are ready to take those family vacations, Bean said.

“People are traveling today. People are going,” she said.