Opportunities for new entrants in the US airline market will be more limited over the next five years, Airlines for America’s (A4A) chief economist said Thursday.

Speaking at the FAA Aviation Forecast Conference in Washington, A4A VP John Heimlich said that new airline entries had been a “wonderful story throughout the deregulation period through good and bad years.”

Heimlich said he did not see that picture changing, but there were new and daunting challenges today that would slow the numbers of new entrants compared to five years ago. These include high energy prices, the lack of niche opportunities and growing competition from surface transportation modes, including the bus. The US is seeing a large expansion of new bus services between major east coast cities.

“It’s going to be a tougher climate in the near term,” Heimlich said.