Two airlines are vying for a federal subsidy to provide year-round service to Knox County Regional Airport.

The airline that has served Knox County Regional Airport for the past decade, Cape Air, has competition this year for a federal subsidy that makes it feasible for scheduled air carriers to serve the small regional airport.

California-based Boutique Air filed a proposal last week with the U.S. Department of Transportation, which awards the Essential Air Service Program subsidy, to be the designated airline servicing Knox County Regional Airport.

Massachusetts-based Cape Air was first awarded the essential service designation and subsidy in 2008, over Colgan Air, which had previously been servicing Knox County. Cape Air’s contract to serve the airport was renewed in 2010 and 2014, without competing bids, according to Jeffrey Northgraves, Knox County Regional Airport manager.

Both airlines are also vying for the federal subsidy to serve Augusta State Airport, which is currently serviced by Cape Air.

The subsidy typically comes as a two-year contract, though Cape Air prefers a four-year contract. Offering a two-year option, Boutique Air’s bid for one year of service to Knox County totaled nearly $2.85 million and Cape Air’s bid for one year of service, with a four-year option, totaled just more than $2.2 million, according to the proposals submitted by the airlines.

Last month, Boutique Air lost a bid for a federal subsidy to provide seasonal air service to Bar Harbor. The subsidy was awarded to Florida-based Silver Airways. Cape Air provides year-round service for Bar Harbor.

Cape Air is the only airline providing scheduled service to and from Knox County Regional Airport, though Penobscot Island Air and Downeast Air offer chartered flights at the airport. Cape Air’s service flies from Boston to Knox County Regional Airport, which last year served nearly 14,000 passengers, according to Northgraves.

“Pretty much everybody is happy with Cape Air,” Northgraves said.

According to its proposal, Cape Air would continue to offer three daily flights to and from Boston during the winter, increasing the number of daily flights to six during July and August. The proposal from Boutique Air offers the same number of daily round-trip flights to and from Boston as Cape Air.

A major difference in service from the two airlines is the type of aircraft used, according to Northgraves. While Cape Air uses two-engine planes, Boutique Air’s planes only have one engine.

Northgraves said one-engine planes have typically been “difficult to sell to the U.S. Department of Transportation,” because if one engine fails there is not a second to fall back on.

With service from Boston to Knox County Regional Airport routed largely over the ocean, Northgraves said if the engine on a single-engine aircraft failed, “you hope you’re [within] gliding distance” to the shore.

Cape Air presented its proposal to the Knox County Commissioners on Tuesday, and Boutique Air is scheduled to give a presentation on July 10. Commissioners have until the end of the month to send their input to the U.S. Department of Transportation. Officials from the DOT will make their decision on which airline will receive the subsidy by the end of August.

“The local input carries a lot of weight,” Northgraves said.

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