MYRTLE BEACH — Traffic dropped in May by double digits at Myrtle Beach International Airport, the fourth decline in passengers in the past five months as airlines have dropped routes and reduced the number of flights, officials said.

About 73,138 passengers flew out of the airport in May, a nearly 24 percent decline from May 2011, according to statistics from the airport. Officials blame the ongoing declines on a shrinking capacity, or number of seats, as carriers such as Spirit Airlines and Allegiant Air have either reduced the number of flights to some destinations or dropped cities they serve from Myrtle Beach.

Another hit came from the loss of Myrtle Beach-based Direct Air, which carried 7,968 passengers out of Myrtle Beach in May 2011. The carrier abruptly stopped flying in mid-March and filed for bankruptcy.

Airport officials plan to alter their strategy in communicating with airlines to regain capacity and keep it, said Mike La Pier, Horry County airports director who received a consultant’s analysis of Myrtle Beach’s traffic trends Wednesday.

“It always concerns you when you see your traffic numbers do what ours are doing,” he said. “It’s a capacity issue.”

One of the biggest losses for the airport, which is amid an expansion scheduled to open early next year, came from Spirit, the largest airline in Myrtle Beach. The airline carries about half of the airport’s traffic every year. In May, Spirit carried 35,147 passengers out of Myrtle Beach, about 12,307 fewer than the same month last year, according to airport statistics. The carrier has had substantially fewer planes taking off at the airport this year -- about 109 fewer between March and June than the same period last year, when Spirit had 353 departures, La Pier said.

Spirit has made several changes to its service in Myrtle Beach this year. It isn’t flying nonstop to Atlanta as it did last year and hasn’t flown to Niagara Falls, N.Y., in May or June because of runway construction that has effectively closed the airport there, Spirit spokeswoman Misty Pinson said via email. Spirit also cut back its Washington, D.C., flights to Reagan National to Saturdays instead of daily flights it had last year because Spirit could not obtain slots, she said. It also has cut the number of flights to LaGuardia in New York, which is Myrtle Beach’s No. 1 market, La Pier said.

“The difference in numbers for May is due to a variety of factors,” Pinson said. “We are certainly committed to Myrtle Beach, which is an important market for Spirit and our customers.”

Spirit’s capacity in Myrtle Beach declined by about 14 percent this year, while Allegiant’s has dropped about 15 percent, La Pier said. Allegiant dropped two cities it serves from Myrtle Beach: Knoxville, Tenn., and Grand Rapids, Mich.

Passenger traffic in Myrtle Beach has dipped four of the past five months, with April’s decline also in the double digits, with a 17 percent drop. For the first five months of the year, about 264,381 passengers flew out of the airport, a nearly 13 percent decline compared to the same period in 2011.

The airport is coming off two consecutive years of record numbers of passengers. About 867,106 passengers flew out of the airport in 2010 and 878,180 in 2011 – another record but short of officials’ goal of 1 million passengers after traffic started sliding in the fall as carriers such as Allegiant Air stopped seasonal service earlier than expected and airline shifts nationally started emerging.

It’s too early to tell if Myrtle Beach’s newest carrier, Vision Airlines, can help make up for the loss of Direct Air. The carrier, which said last week it would cancel two of its eight destinations from Myrtle Beach, only flew for one day in May. Vision already is dropping flights to Toledo and Nashville, saying the demand wasn’t there.

Airport officials said it would take time for Vision’s service to ramp up, adding that advanced bookings for July looked good. The carrier started serving Myrtle Beach on May 31, just a few weeks after announcing it would start flying here.

The airport remains a key in growing Myrtle Beach tourism by opening new markets and making it easier for vacationers to get here, said Stephen Greene, president of the Myrtle Beach Area Hospitality Association.

“Obviously Direct Air was a big impact,” he said. “We recognize that the airport is our investment for the future. We’ve kind of taken a couple of shots lately…but I think it is too important for us not to push forward with growth.”

The airport itself is growing with a $118 million expansion underway that will add a 240,000-square-foot terminal and new parking and rental car facilities. The number of gates will grow from seven to 13, with the ability to grow to 18 gates. The decline in passengers doesn’t mean the expansion isn’t needed, La Pier said.

“There is absolutely no room for us to grow in the existing facility,” he said.

The expanded section should be up and running by mid-February; officials are aiming to have it operating before the spring golf season kicks in, La Pier said.

The goal also is to have more seats by then, with airport officials planning to be more aggressive in talking with airlines earlier and staying in front of them, he said.

Contact DAWN BRYANT at 626-0296 or at dbryant@thesunnews.com or follow her at Twitter.com/TSN_dawnbryant.