During the winter, airplanes using the Norman Y. Mineta San Jose International Airport change to a southern departure, which places them over Willow Glen because of wind patterns, said airport noise-abatement manager Jaime Locquiao.

Locquiao said complaint calls have risen from Willow Glen residents in the past few months. In November 2003, there were 13 complaints from Willow Glen residents, up from 10 in October.

The seasonal change in flight patterns is necessary, but some residents said they wish that the airport would be stricter in its enforcement of the 11:30 p.m. to 6:30 a.m. curfew.

"There's definitely a certain number of noise intrusions in the middle of the night," said former mayor and political adviser to Citizens Against Airport Pollution Janet Gray Hayes. She said she called about a plane she heard at 5:45 a.m. and was told it was a corporate jet.

"It was noisy as all get-out," she said.

In October 2003, the federal airline industry regulators approved San Jose's change from a weight-based curfew to a noise-based curfew, which still allows airplanes under the old tonnage ordinance to fly past curfew because of a grandfather clause.

This compromise was reached after a federal judge ruled in favor of Oracle billionaire Larry Ellison. His charter jet was constantly flying into the airport after curfew.

It's the first time in the country that the Federal Aviation Administration has allowed a city to change its curfew after the 1990 Airport Noise and Capacity Act froze existing curfew requirements, District 6 Councilman Ken Yeager said.

Yeager said the new ordinance allows the city to levy fines on noncompliant curfew intrusions that were not related to weather, mechanical problems or air-traffic control.

Citizen Against Airport Pollution Chairman Kenneth Hayes said his organization has accepted the new curfew, which is better than no curfew, but said "we are withholding judgment as to how it will work out."

But Hayes said he wished the noise-level limits could have been made stricter.