Cape Air's popularity here continues to climb steadily higher.

Almost every month since starting service in late March, the airline is carrying more passengers between Lancaster Airport and Baltimore-Washington International.

September was its best month here so far, with 855 passengers arriving at the local airport or departing via Cape Air.

"The trend we've seen so far is very, very gratifying," said Andrew Bonney, Cape Air's vice president of planning.

"Six months into it, for a market that didn't have service for so long, this is magnificent. This is absolutely what we want to see," said Bonney on Wednesday.

Still, passenger counts will need to keep ascending in order for Cape Air to maintain service here once federal subsidies expire, though that could be more than two years away, an airport official said.

Cape Air has flown more than 4,300 passengers between Lancaster Airport and BWI to date, carrying mostly business travelers.

The figures show that, with the exception of a downturn in July, when business travel typical dips, passenger counts have risen significantly every month. That includes a 17 percent jump in September.

Measured another way, Cape Air's nine-passenger Cessna 402s were 15 percent full in March, when service began. In September, that figure hit 34 percent.

"We get positive feedback all the time. Everybody seems really happy with it. They just love the convenience," said Joyce Opp, the airport's marketing director.

"People say it saves them three-plus hours (compared to driving to BWI)," added Opp.

Bonney said the steady growth is the result of several factors — broadening awareness of its service, frequent flights (five roundtrips daily) and low prices ($100 a roundtrip).

"Our model is low fares and high frequency. That will rebuild the public's use of air service at Lancaster Airport," he said.

Frequent service is a key feature because it helps passengers make easier connections with other flights, observed Cape Air spokeswoman Michelle Haynes.

Cape Air's service also is flexible, responding to community needs.

Last week, Manheim Auto Auction officials told Cape Air that dealers on the initial incoming flight were arriving too late to get to Manheim in time for the first auction.

Within two days, Cape Air had adjusted its schedule, advancing that initial arrival time by 85 minutes, to 7:55 a.m. The revision takes effect Oct. 11.

"We want to make sure we're as useful as possible to the community," said Bonney.

Lancaster Airport had been without commercial service since September 2007, when a federal subsidy for USAirways Express to provide service between here and Pittsburgh expired.

Cape Air's arrival gave Lancaster Airport service to BWI for the first time since 1992.

While Cape Air is off to a strong start here, exceeding the performance of most start-up markets, Opp said passenger counts will need to double in order for Cape Air to afford to fly here without a subsidy.

"It's doing well. It needs to do better," she said. "It needs to get to a load factor of at least 70 percent to be profitable without a subsidy. We're very optimistic we can get there, based on the feedback we're getting."

But clues being sent by Congress make it appear the service won't have to stand on its own financially until 2012 at the soonest.

Cape Air has a federal Essential Air Service grant of $388.69 per flight through March, for a total of $1.37 million. Another two years of EAS subsidies here would be provided in a bill before Congress.

"We're 99 percent comfortable that we'll be (included in those two extra years)," said Opp.

tmekeel@lnpnews.com