In the pecking order of mass transit projects, trains always seem to trump buses — even if the trains are designed to go in the wrong direction.

“Some will say that buses aren’t sexy,” said Janette Sadik-Khan, a former New York City transportation commissioner.

But Ms. Sadik-Khan recently joined other New York transportation authorities and experts in recommending buses as the most practical answer to the problem of improving transit connections to La Guardia, one of the busiest airports in the country.

Even at a greatly reduced price tag, however, Ms. Sadik-Khan admitted buses might be harder to get excited about. “Everybody loves the idea of a rail connection to the airport,” she said. And while bus routes may not capture the public imagination like a new train, transit officials have concluded that more people were likely to use the proposed bus service than a rail connection.

New York City’s transportation planners last week abandoned the idea of building an AirTrain to La Guardia Airport at a cost of more than $2 billion. The rail link had been a pet project of then-Governor Andrew Cuomo, who faced criticism that he ignored alternatives in favor of a plan that would burnish his legacy. Critics also complained that the AirTrain’s route would carry Manhattan-bound passengers in the wrong direction to reach a city-bound subway or train.

Mr. Cuomo’s successor, Kathy Hochul, ordered a review of the rail plan a few months into her tenure. The Port Authority of New York and New Jersey, which operates La Guardia, convened a team of engineering and construction firms to study the proposed AirTrain and 13 other options for improving airport transit. They concluded that it would take at least 12 years and cost as much as $7 billion to extend a subway line to La Guardia.

None of the other options, including an AirTrain, would attract as many riders as better bus service, said Ms. Sadik-Khan, who was one of three members of a panel appointed to review the engineers’ analysis. She said the review concluded that the bus services would draw about five million passengers annually.

The panel backed a plan to enhance an existing public bus connection to the No. 7 subway line in the Woodside section of Queens and to create a direct shuttle between the airport and the N and W subway lines in Astoria. That solution would cost an estimated $500 million, a fraction of the cost for the now-scrapped AirTrain. Gov. Hochul accepted the recommendation and the Port Authority’s board of commissioners is expected to authorize it within three months.

Having overseen the creation of some express bus routes in the city, known as Select Bus Service, Ms. Sadik-Khan is a proponent of luring travelers out of cars by getting buses moving faster through city traffic. A decade ago, when she worked in City Hall under Mayor Michael Bloomberg, the Metropolitan Transportation Authority conceived Select Bus Service routes to La Guardia from the Bronx, Manhattan and in Queens.

But speeding up buses in the clogged streets of the city is not a small undertaking. It requires adding or converting lanes to give buses space of their own and reprogramming traffic signals to give them priority.

The engineers estimated that the suggested improvements to the Queens route, known as the Q70, would cost about $100 million. A large portion of that total would go toward turning a mile-long section of the shoulder of the northbound Brooklyn-Queens Expressway into an exclusive bus lane, their report said.

The more expensive part of the chosen solution would be the creation of a shuttle service to the Astoria Ditmars subway station. The engineers estimated that it would cost about $340 million, including the purchase of 17 electric buses, construction of a depot and installation of charging stations.

They determined that improvements would also be needed at the subway station, which has no escalator, to make it more accessible to travelers with disabilities. When the shuttle is operating, which the engineers estimated would be in four to five years, it would cost about $14 million a year to operate, they concluded.

The Port Authority, which would pay for creation of the shuttle, said it had not made decisions yet about a fare for the service.

In April, Gov. Hochul announced that, while she awaited the panel’s recommendation on alternatives to the AirTrain, she had eliminated the fare on the Q70 bus. John Lindsay, a spokesman for the M.T.A. said the state and the Port Authority were contributing $1.2 million a year toward the Q70.

Since then, ridership on that bus has risen faster than the steady increase in overall transit ridership, according to figures provided by the transportation authority. Last year, more than 2.1 million passengers rode the Q70, an increase of more than 1 million from 2021, those numbers show.

In the first two months of 2023, the Q70 had more than 340,000 riders, up more than 50 percent, from about 220,000 riders in the first two months of last year.

“Governor Hochul has been clear that New Yorkers deserve world-class transportation to world-class airports,” Mr. Lindsay said. “While the Port Authority begins implementing recommendations on mass transit solutions for La Guardia, Governor Hochul will continue to support a Q70 bus that is free for all customers.”