The MTA should be one of the city's most sought-after landowners. But critics say the cash-strapped agency has not made the right moves to quickly cash in on the value of its two side-by-side parcels of land on the far West Side of Manhattan.

Just north of the Lincoln Tunnel entrance in Manhattan sit the West Side rail yards on a 13-acre site, which the Metropolitan Transportation Authority decided to allow the New York Jets to develop. Another site is the adjacent Eastern Rail Yard, which New York City's budget office last year estimated would bring in $1.7 billion to the city's coffers over the next 30 years.

But observers such as neighborhood activists and policy groups say the MTA board should have held a more rigorous bidding process for both plots.

For example, an MTA appraisal said the West Side yards could fetch nearly $923 million. However, the board agreed last month to sell development rights to the Jets for $250 million. That bid was far less than two competing offers, including a $400-million bid from Cablevision.

Observers say the MTA is also making a mistake if it allows the city to also give away the Eastern Rail Yard without any public bidding.

"I think their obligation is to sell [the lands] at the highest possible price," said Richard Ravitch, a former MTA chairman who has been critical of the deal with the Jets.

However, the MTA board says it has made the right decisions for the agency. As part of the vote to allow the New York Jets to build a stadium on the West Side, it said it planned to hold on to 4.4 million square feet in development rights to sell at a future date.

One estimate provided by MTA adviser Newmark & Co. says the MTA could sell those rights for as much as $1 billion - far more than the $440 million that six real-estate firms had offered last month.

The Jets stadium and decision to hold on to the rights is a "better deal all around," said Jim Simpson, an influential MTA board member who heads up the agency's real-estate committee.

"If we don't do this now, that site may sit for another 20 years empty," Simpson said.

But unlocking those air rights won't be quick or simple. In addition, the agency may find itself in a sticky situation competing with the city's plans for the Eastern Rail Yard development rights.

"They're now counting on being able to sell millions of square feet of development rights at the same time the city is also trying to sell development rights in the same area," noted Jeremy Soffin, spokesman for the Regional Plan Association. "There are no guarantees, and ... a lot of people have questioned whether the demand is there yet."

The MTA could get a windfall if the real-estate developers who eventually flock to the West Side pay the MTA for those extra development rights so they can build their new office towers taller than what their blocks are zoned for.

Transferring rights to adjacent properties is fairly common, and the City Council last year completed an extensive rezoning of 59 blocks on the West Side in hopes of attracting new office towers and residences to the blocks around 10th and 11th avenues and north of 34th Street.

Still, the MTA faces many hurdles in getting developers to bid up those air rights. For starters, although the real-estate market remains hot in New York now, many experts expect it will cool down as interest rates rise. "Competition to build will be less in a higher interest-rate environment," noted Myers Mermel, chief executive of TenantWise Inc., a company that advises clients on commercial real-estate deals.

Another problem: The sudden availability of development along 10th and 11th avenues may result in a glut of space after construction of the No. 7 train extension is completed, which is expected in 2010. Experts don't expect office buildings to begin construction until after the line is completed, and only then will bidding begin for rights.

But those who support the MTA's plans say the public must be patient when it comes to seeing the profits of the land deals. "People are confident in the development potential of Manhattan, but recognize that this is going to roll out over the next 20-30 years," said Kathryn S. Wylde, president and chief executive of the Partnership for New York City, a nonprofit group of business executives.