Some airports, however, have voluntary curfews.

Our community leaders should consider patrolling their own schools (which is done in Philadelphia) and setting voluntary curfews for our youth.

Such a flight would occur 31 minutes before the voluntary curfew of midnight to 6:30 a.m. ends.

But there are a number of voluntary curfews, including one at La Guardia, which has a midnight-to-6 a.m. ban.

The voluntary curfew began in 1984 as a courtesy to people who live near the airport.

For the last 20 years, airlines have observed a voluntary curfew prohibiting takeoffs or landings there between midnight and 6:30 a.m.

Now almost all planes comply with a voluntary curfew and do not use the airport between midnight and 7 A.M.

The voluntary curfew has been recognized for 20 years.

"The voluntary curfew could stop at any time," said Mr. Pierro, a long-time airport monitor.

The grant was contingent upon the county's agreement to place fees collected from airlines that break a voluntary overnight curfew in an escrow account.