PRESQUE ISLE – A federal order issued Tuesday will require that CommutAir continue service at the Northern Maine Regional Airport until a replacement carrier is found, according to announcements by Maine’s congressional delegation.

The order, issued by the U.S. Department of Transportation, also will allow Business Express to leave the market after Dec. 3.

In addition, the federal DOT is asking air carriers to submit proposals to serve the Aroostook County airport.

“We’re pleased with the decision,” U.S. Rep. John Baldacci said Tuesday during a telephone interview. “As a member of the House Aviation Subcommittee, I recognize the importance of air service to the economy and quality of life in northern Maine.”

A joint statement by U.S. Sens. Olympia J. Snowe and Susan M. Collins also voiced support for the DOT’s decision.

“Reliable air service in our nation’s rural areas is not simply a luxury or a convenience, it is an imperative and we remain committed to the Presque Isle market,” said the senators’ statement.

Presque Isle Airport manager Greg Willard also said he was pleased with the arrangement. Willard traveled to Washington, D.C., earlier this month to discuss with situation with airline executives and the congressional delegation’s staff.

In September, Business Express announced it planned to leave Presque Isle. The airline had provided the airport with 26 nonstop round trips to Boston each week.

Later that month, CommutAir filed its intent to terminate its service, which included one one-stop and two nonstop round trips a day to Boston.

Since the airport has an essential air service designation, the government requires at least two nonstop round trips daily to Boston with capacity to carry 40 passengers each way daily.

CommutAir now operates under the umbrella of U.S. Airways Express. On Dec. 3, the carrier will operate as a Continental Express partner, according to the order.

CommutAir will be required to continue serving Presque Isle until the federal government has reviewed the proposals it receives to serve the county airport.

In requesting the proposals, the order said that carriers may submit a plan for four nonstop or one-stop round trips per day to Boston with 15-seat or larger aircraft.

Service to other transportation hubs that provide access to the national air transportation system also will be considered.

The potential replacement carriers would not include a subsidy from the government to fill the vacancy.

“We expect that any subsidy would be minimal and short-term in nature,” the order said.

Presque Isle is a “very atypical case,” under the federal Essential Air Service Program, with its large passenger numbers, the order said.

The order noted the multimillion-dollar commercial developments going on in Aroostook County, which include the planned construction of two potato processing plants, and that the closest other large airport was in Bangor.

In 1999, almost 29,000 passengers boarded a plane in Presque Isle, with the possibility of that number growing, the order said. A recent study found that the Presque Isle-Portland market could produce another 4,000 enplanements annually.