A plane takes off from Hancock County-Bar Harbor Airport in Trenton in this Feb. 18, 2011 photo.

A seasonal airline will stop serving B ar Harbor Airport on Thursday, a month ahead of its scheduled departure, the airport’s manager said Thursday.

PenAir’s contract expires on June 30, but the airline’s “critically low” pilot and mechanic staffing levels forced its early departure from the Trenton-based airport, manager Bradley Madeira said.

Madeira’s news follows PenAir’s announcement on Monday that it will also leave the Presque Isle airport on Thursday.

[PenAir ends its service to Presque Isle airport a month early]

Madeira said he did not have an estimate on the number of passengers affected. Bar Harbor’s year-round airline, Cape Air, will continue to serve the airport.

‘For us it will simply reduce the amount of air carrier seats available to the market in and out of our airport for the month of June. Luckily we still have Cape Air operating as they normally do. It is unfortunate about PenAir, but we will get through it,” Madeira said Thursday.

Attempts to find another seasonal airline to serve Bar Harbor until July 1, the date Silver Airways of Fort Lauderdale is due to replace PenAir, were unsuccessful, Madeira said.

“There is simply not enough time to coordinate that service with

another air carrier and with the [U.S. Department of Transportation] before it is needed,” Madeira said.

[Florida airline to start serving Bar Harbor Airport on July 1]

Summer is typically the airport’s busiest season. Located on Caruso Drive in Trenton, Bar Harbor Airport serves Hancock County and is owned and operated by the county and governed by the Board of County Commissioners. It has a 5,200-foot and a 3,364-foot runway.

Alaska-based PenAir also announced that it is ceasing operations effective June 1 for its routes to Boston from Presque Isle and Plattsburgh, New York.

PenAir has held those contracts, subsidized through the federal Essential Air Service Program, since 2012 but lost all of them to other airlines this spring.

The lack of a second carrier at Presque Isle and Bar Harbor could decrease the passengers the airports serve, which could reduce their federal maintenance funding, officials have said.

Passengers due to fly PenAir from Bar Harbor after Thursday are advised to contact PenAir at 800-448-4226 for refunds.

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