Airport Noise Restrictions to Be Lifted for 5 Months : Aviation: FAA responds to pilots’ complaints that cutting back jet engines at lower altitudes to reduce loudness is dangerous. Takeoff rules will change April 1.

Hard-won noise restrictions at John Wayne Airport will be suspended for five months, starting April 1, as the airport experiments with new takeoff procedures.

Pilots complain that the current takeoff procedures at John Wayne are dangerous because in some instances they must cut back their engines at an altitude of 500 feet to reduce noise. Because of those concerns, the Federal Aviation Administration is expected to ban power cutbacks below 800 feet later this year.

During the five-month test period, jets will cut back power at 800 feet, and 14 noise sensors stationed along the flight path will record the results.

As a concession to local residents, the FAA will allow aircraft to rapidly climb to 5,000 feet instead of the current 3,000 feet to reduce noise. Airport officials have long sought the higher altitude, but the FAA rejected the request until now because it involves changing a flight path.

Residents of Corona del Mar and Balboa Island are expected to benefit from the changes at the expense of inhabitants of Santa Ana Heights. That’s because jets will be higher and thus less noisy by the time they reach the coast, but they may be at full power when passing over Santa Heights at the end of the runway.

The airport’s test program will be considered by the Newport Beach City Council next week, and by the Board of Supervisors on March 24. Both governmental bodies must approve the plan, along with the Airport Working Group, a homeowners’ organization, and Stop Polluting Our Newport, an environmental group.

Their cooperation is needed because they were all parties to a 1985 court-approved settlement that ended years of anti-noise litigation between the city and homeowner groups on one side and the county, which owns the airport, on the other side.

In a rare show of cooperation, airport spokeswoman Courtney Wiercioch and Newport Beach Councilman Clarence J. Turner said all parties involved have agreed that the tests should go forward.

Airport officials said they will keep close tabs on the airlines to make sure that none of them tries to take unfair advantage of the test period to increase their use of noisier jets.

If the test results show a significant worsening of noise for airport neighbors, said Ken Delino, an assistant to the Newport Beach city manager, “We would hope to persuade the FAA” not to ban power cutbacks below 800 feet.

If pilots are not allowed to reduce power at 500 feet, some aircraft that serve the airport may be unable to meet its noise limits. Airport officials would have to either bar those aircraft and disrupt airline flight schedules, or adjust some rules to allow more noise.

If noise restrictions are loosened, Turner said his city might have to go back to court and reopen the 1985 court settlement. “We would have to return to confrontation,” Turner said.

Edwin C. Hall, a Santa Ana Heights anti-noise activist, said he was unaware of the upcoming noise tests, and doubts that most of his neighbors will notice a big difference.

“For the people in this tract,” said Hall, “it’s a relief when we see an airplane getting up higher, faster, because that means it’s going past us and we’re safe” from a crash.

The key issues for homeowners, Hall said, is not the power cutback but alleged violations of the airport’s nighttime curfew and the fact that some aircraft make a shrill sound during takeoff that is more irritating than the noise from louder planes.

Assuming that the altitude for the power cutback is raised permanently, the county most likely would have to expand its program of buying or insulating homes under the flight path that experience noise levels above state health standards.

Currently, of an average 94 daily departures at John Wayne, fewer than 20 make power cutbacks below 500 feet. The rest are quiet enough to maintain power to higher altitudes and still comply with noise regulations.