Local lawmakers said they were confident that their city councils and the county Board of Supervisors -- most of which have received closed-session briefings on the agreement -- would approve the deal.
"I think they will see the good in this for our city, just as I do," said El Segundo Mayor Kelly McDowell. "Everybody benefits, everybody gave a little and everybody got a lot."
McDowell and others hope FAA officials will decide within days not to contest the deal.
Donn Walker, an FAA spokesman, said: "We will review this agreement, but we won't be able to comment on it until we've looked at it."
Despite optimism that federal officials will approve the deal, airlines object to one of the most controversial elements -- a plan to decrease the number of gates where airplanes park from 163 to 153.
"There are a number of complexities associated with the settlement agreement that was reached without airline input," said David A. Castelveter, a spokesman for the Air Transport Assn., an airline trade group. "We will conduct a careful and thorough review of the agreement."
Carriers do not support a reduction in airplane parking spots, he said. The cash-strapped airlines would be required to pay up to half the costs of modernizing LAX through higher rents and landing fees. Federal grants and fees paid by passengers would make up most of the rest.
Even so, airlines said they support the plan to move the southernmost runway 55 feet closer to El Segundo, widening the distance between the two parallel runways enough to create a central taxiway. Airport officials said the work should not delay flights.
They said the settlement also allows them to begin construction next year on several other projects. One of these is the $410-million upgrade of the Tom Bradley terminal that includes expanded gates for the massive 555-seat Airbus A380.
Also on deck is a $400-million project to overhaul the airport's complex baggage system and install explosives-detection machines.
"We're not losing any time," said Paul Haney, an airport spokesman. "We'll be improving the airport while we figure out what our next project will be."
To devise a new plan, airport officials will meet with residents and airlines to come up with projects that will improve security at LAX and update its worn-out terminals.
Rand Corp. experts have criticized the check-in center, saying it would make travelers more vulnerable to a terrorist attack. And passengers have long viewed the airport as one of the nation's most inconvenient and unkempt such facilities.
Several projects in the modernization plan, including a new terminal on the western edge that would replace the remote gates near the sand dunes and a consolidated rental car facility, are seen as likely contenders for any new plan.
But some of the most controversial proposals put forward by Hahn -- including the check-in center and the demolition of Terminals 1, 2 and 3 and of parking garages in the central terminal area -- are considered moribund.
Airport officials will not acknowledge this directly, however, because the massive check-in center must remain in play, at least on paper, to make the traffic analysis work in environmental studies.
If the city officially killed some projects, it might have to go through the lengthy environmental review process again.
Los Angeles City Councilman Bill Rosendahl, whose district includes the airport, said the projects "that are bad, we're going to replace them, we're going to have alternatives."
In the settlement, the city also agreed to:
* Take steps to contain passenger growth if LAX serves 75 million passengers in 2010. If that threshold is reached, the airport will eliminate two gates a year for five years, reducing the total number to 153. LAX expects to handle 62 million passengers this year.
* Invite the FAA, the Southern California Assn. of Governments, airport operators and area counties to develop a plan to encourage airlines to spread air traffic among the region's airports, including Ontario International and the Palmdale facility, both of which the city of Los Angeles operates.
* Accelerate the disbursement of up to $240 million to soundproof homes in unincorporated Los Angeles County areas, El Segundo and Inglewood.
The city's airport agency will start its third attempt in 11 years to devise a palatable proposal to upgrade the 77-year-old facility as soon as the litigation is dropped in state and federal court.
Sued by several cities, LAX agrees to limit growth and halts plans to rebuild runways, a terminal and parking.
In her first year back in the pilot's seat, Lydia Kennard has managed to get some long-delayed projects off the ground.
Officials will outline options for improving traffic flow, a key element in updating the airport's design.