Tailwind Air has delayed a plan to fly seaplanes from Manhattan to College Park Airport in Maryland while the Transportation Security Administration and Federal Aviation Administration assess safety concerns over the proposed operation.

The flights were due to begin on Tuesday. As questions persisted over the use of the airport, the airline announced that it plans to operate initial service to the DC area using a private terminal at Dulles International Airport. This option also seemed in question due to the unusual nature of Tailwind’s operation.

On Monday, Tailwind said it was delaying its launch in the region by at least two weeks as it tries to strike a deal with an airport.

Tailwind executives said last month they had a way to access restricted airspace around the capital using exemptions created for College Park and two other small airports in Maryland. The airline had gone so far as to carry out a test flight.

Tailwind relies on a section of airline regulations that allows commuter flights to provide scheduled service using small aircraft without meeting all the requirements imposed on large airlines. Published procedures for College Park Airport do not mention restrictions on types of flights, but shuttle operations are relatively rare and federal authorities have more questions about the idea.

“There are post-9/11 security concerns related to contracted commercial carriers operating in restricted airspace in the National Capital Region,” TSA spokesperson Carter Langston said in an email. . “To that end, the TSA and FAA are working with Tailwind Air to address and explore security options. As this is a transportation security issue and involves sensitive security information, we will not comment further on these concerns.

The FAA referred the questions to the TSA.

Seaplanes arrive in Washington. But they will land on… earth.

Tailwind advertised service to Dulles as an alternative to College Park. Tailwind posted an announcement about the change on its website early last week, only to drop it a few days later.

“There are a lot of stakeholders, obviously, in this space,” said Alan Ram, CEO of Tailwind. “I would say a positive outcome is by no means assured, but I think the conversation was surprisingly constructive.”

Because Tailwind does not use TSA security screening for passengers, it cannot access the main terminals and would have to use a private terminal at the airport. But David Mould, a spokesman for the Metropolitan Washington Airports Authority, which operates Dulles, said Monday the idea was still under consideration.

“It looks like it’s going to set them back a bit,” Mold said. “It’s taking longer than anyone had hoped.”

College Park Mayor Patrick Wojahn disclosed the federal review at a city council meeting last week, saying the launch of Tailwind would be delayed by 45 days. The council was meeting with the head of the local airport authority to discuss a needed change to airport rules, which prohibit regular commercial service.

Some council members wondered if the service would be noisy, but local officials seemed willing to support the change on a trial basis.

The airport, which was founded in 1909 and claims to be the oldest in the world still in operation, is managed by the Maryland-National Capital Park and Planning Commission. Angel Waldron, spokesman for the commission, said officials are confident the partnership with Tailwind will eventually go forward.

“We are willing and excited about this opportunity,” Waldron said.

Tailwind plans to use a fleet of eight passenger seaplanes to fly trips between a marina on Manhattan’s east side and the Washington area. The airline charges $395 for a one-way ticket, presenting itself to time-conscious business travelers as a faster alternative to jets or Amtrak.