Since March 20, on most days about 200 planes have been using the new flight path, taking off west and then arcing to the north -- a right turn -- before heading east.

That flight path has divided the community.

Those under the new departure path complain of sleepless nights, unusable patios and depreciating home values. The Federal Aviation Administration and McCarran noise complaint hot lines have been flooded with such complaints.

Those living elsewhere in the valley say they have had to live with airplane noise for years, and it's about time residents under the new flight path share the burden.

The city of Las Vegas has a lawsuit pending in the 9th Circuit Court of Appeals, challenging the FAA's finding that the flight path would have no significant impact on the environment.

The city pitched restricted flight times as a compromise with federal and airport officials.

But Walker said several issues make it impossible to limit the hours of flights. In particular, a 1990 federal law requires airports seeking to restrict air space for noise reasons to follow a lengthy set of rules. The rules demand that "the restriction is reasonable, nonarbitrary, and nondiscrimatory."

That condition would make it impossible to eliminate early morning or late night right-turn flights without also eliminating all other departures at those times, Walker said.

Since the law's passage no airport has successfully met the federal requirements to restrict aviation space, Walker said. As a result, the airport is not going to look at restricting flights, he said.

"We're not going to spend money on a task that's impossible," Walker said. "Under the rules, that would basically be a non-starter."

Del Meadows, FAA air traffic manager for the Las Vegas district, said the busiest hours for the airport, and the hours when the right turn is most needed for efficiency and capacity, are between 10:30 p.m. and 12:30 a.m.

"We didn't create (the new flight path) to take the noise and move it someplace else. We did this for airspace reasons," he said.

Ultimately, though, any decision to restrict hours of operation would have to be made by the airport, Meadows said.

Airports with restricted flight times, known as curfews in the aviation community, had them in place before the 1990 law and the restrictions were grandfathered in, Walker and Meadows said.

Anne Kohut, publisher of the Airport Noise Report, a national newsletter, agreed that airports cannot put mandatory restrictions to curb noise.

But she said other airports have had voluntary noise procedures put in place, such as using only certain runways late at night. Those voluntary procedures would have to be agreed upon by community representatives, airport officials, the FAA and airlines, she said. Getting that kind of consensus is unlikely in Las Vegas' contentious debate.

Clark County and the FAA have recently stepped up their defense of the departure path, saying it improves efficiency and capacity at the airport.

"Let me say, without equivocation and without hesitation, the new departure is every bit as safe as the previous one and every other procedure in use at this airport," Meadows said.

In response to Meadows' statement, Mayor Oscar Goodman said: "I'd like to interrogate him under oath."

Goodman has said his major concern about the flight path is safety.

Councilman Steve Wolfson said he has set up a meeting with Walker for later this week to discuss options for noise abatement, including limiting flight times.

"The community is as bothered and annoyed and appalled as ever," Wolfson said.

But FAA and McCarran officials said some of the complaints that have poured in since the change are unfounded.

The FAA gets complaints about the right turn on days when that configuration is not in use, Meadows said.

Some complaints have come in from residents near Palace Station, at Sahara Avenue near Martin Luther King Boulevard. A takeoff pattern over that area has been used for decades when high or shifting winds force the airport to use different runways for departures.

Other complaints have been about planes at 4 a.m., when there are no flights making the right turn. That noise is from flights going to the Nevada Test Site as they have for years.

"Any airplane in the northwest area now that's up there for any reason, people are attributing to the right turn," Meadows said.