Top MTA officials went for a ride Monday on a double-decker bus, which is being rolled into service for a trial run.

Officials say the 13-foot buses are cheaper to maintain, carry more passengers, and are more efficient than the extra-long buses currently in use.

"This bus is used around the world. It does a great job in both express and local. We're try it on several routes in the city," said MTA bus president Joseph Smith. "We have to get a few trees trimmed here and there, but this bus, from an environmental standpoint, carries more people that any other."

The bus can seat 83 people, 20 people more than the largest bus currently in the fleet, the so-called "articulated buses" with the accordion-style joint in the center. The double-deckers also cost about a quarter-million dollars less, and are expected to require less maintenance.

Buses like these disappeared from city streets in the 1950s and made only a brief return in the 70s.

"I'm extraordinarily pleased to see us going back to the future," said New York City Transit President Howard Roberts.

Some of those vintage buses are still maintained and occasionally put out for display. As for the new double-decker, officials plan to use them only on express and limited routes. The concern is the increased loading time required for people to go up and down the stairs.

"The big questions are people getting on and off the bus, how the bus holds up mechanically, and what customer reaction to it is," said Roberts.

The reaction from New Yorkers on Monday was overwhelmingly positive.

"It's nostalgic for people that remember double-deckers from years ago," said one New Yorker. "And also it's a practical thing. A lot of other cities and Europe use them a lot, so why not here."

The new bus will run on the M5 on Fifth Avenue, M15 on First and Second Avenues, the X17 Express between Staten Island and Manhattan, and the BxM3 Bronx-Manhattan express.