PORTLAND (AP) – JetBlue officially began service to the Portland International Service on Tuesday, instantly becoming the second-biggest airline serving the airport in terms of seating capacity, officials said.

Even before its arrival, the low-cost carrier already was having the desired effect of driving down airfares, much like Southwest Airlines did when it arrived at the Manchester, N.H. Fares on some routes have dropped by more than $100.

“There’s a clear reduction in fares in every market that JetBlue serves from Portland,” said Steven W. Hewins, president of Hewins/Carlson Wagonlit Travel in Portland.

The first JetBlue flight to Portland from New York’s John F. Kennedy Airport carried Gov. John Baldacci and other dignitaries.

Fire trucks sprayed water into the air on either side first JetBlue Airbus A320 as it taxied to a gate shortly before 11 a.m. Baldacci shook hands with the passengers as they left the airplane and stepped into the airport.

JetBlue will offer four round-trip flights to New York every day. From there flights will connect with more than 30 other destinations.

The A320 aircraft used by JetBlue have 156 seats, making them the biggest jets using the Portland airport. Most other airlines have scaled back to smaller regional jets, which typically offer seating for 50 to 70 passengers.

That means the number of seats available to and from Portland jumps 20 percent from Monday to Wednesday, when JetBlue’s full complement of flights takes effect.

“Overnight, they (JetBlue) are the second-largest carrier at the jetport,” said Gregory Hughes, marketing manager for the Portland International Jetport.

Airport officials hope to use JetBlue and the lower fares to win passengers back to Portland.

The Portland International Jetport was setting passenger records almost annually from the 1990s up to 2000, but passenger counts plummeted in 2001 and 2002 as a result of the Sept. 11, 2001, terrorist attacks.

As those fears were beginning to ease, a general slowdown in the economy cut into both business and leisure travel.

Fewer seats and rising demand have allowed the airlines to cut back on the number of discounted seats they offer to firm up fares. Portland was already a relatively high-fare market before fares started rising.

The jetport commissioned a study last year that found that in the Portland market area, 41 percent of air travelers flew out of Logan Airport in Boston and 16 percent flew out of Manchester. Only two out of five air travelers chose the airport closer to home.

Hewins said he was at a travel agents’ convention in Florida last week and other cities were envious that Portland managed to land JetBlue.

Several told him they wished they had JetBlue in their city.

“It’s a feather in Portland’s cap,” he said.

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