Top Los Angeles International Airport officials Monday publicly questioned whether the Federal Aviation Administration was adequately maintaining its air traffic control equipment after a key landing system malfunctioned, the fourth mishap in less than a month.

“Enough is enough,” said Frank Clark, executive director of the nonprofit organization that represents airlines operating at the Tom Bradley International Terminal. “The frequency of these within a relatively short interval does create a cause for concern and leads us to wonder if there isn’t something more systemic going on with maintenance and age of equipment.”

The latest breakdown occurred Monday morning with the Instrument Landing System, the same equipment on the airport’s south airfield that malfunctioned a week ago. The system shut down for about 40 minutes, slowing air traffic into LAX.

To the dismay of LAX officials, the FAA still hasn’t determined why the Instrument Landing System went down last week.


“This is clearly a systemic problem with the equipment,” said Lydia Kennard, executive director of Los Angeles World Airports, the city agency that operates LAX. “We believe there’s something fundamentally wrong with the equipment. It has to be fixed or replaced.”

The dissent marks a shift in tone by airport officials, who until now have been largely circumspect about the problems.

The repeated problems also are prompting inquiries from outside the airport: Sen. Barbara Boxer (D-Calif.) plans to ask for an explanation of the system mishaps when she is at LAX on Thursday for a briefing on new security procedures, said Natalie Ravitz, the senator’s communications director.

FAA spokesman Ian Gregor maintained Monday that the landing systems were sound and that the recent equipment outages were unrelated.


The summer of turbulence involving LAX started when controllers at a Palmdale center that handles high-altitude flights completely lost communication with pilots for several minutes on July 18 after a backup power system inexplicably went down.

FAA investigators are still trying to determine what caused the outage, which affected airports throughout Southern California. Controllers have used the backup power system several times since the outage without a problem, Gregor said, as a precaution when there was high demand on the main power grid.

On July 26, a system designed to alert controllers at the LAX tower to potential collisions on the ground was partially disabled minutes before a turboprop plane narrowly missed a regional jet that had strayed onto its runway.

On Aug. 7, a system on LAX’s southern airfield that helps pilots land on foggy days was out for 3 1/2 hours, delaying dozens of flights for more than 90 minutes.


On Monday morning at 10 a.m. the same equipment went down. Technicians reset the equipment by 10:40 a.m., but the outage delayed arrivals for up to 45 minutes for part of the morning.

Aviation experts said it was not unheard of for a single air traffic system to go down several times at the same facility.

But the situation at LAX -- with three different systems at different locations failing within a few weeks -- is another matter, they said.

“Having three things fail in three different locations is pretty unusual,” said Richard Marchi, senior advisor for policy and regulatory affairs at Airports Council International, a trade group.


The city operates LAX and the FAA manages controllers in the LAX tower who direct air traffic. The FAA operates numerous air traffic control systems in the tower and on the airfield and has regulatory oversight over airport operations. The agencies typically have cordial relations and are loathe to criticize one another publicly.

Chief pilots for the airlines that operate at LAX plan to discuss the FAA equipment outages at an annual meeting in the coming weeks, Clark said.

The FAA is still struggling to figure out why the mishaps keep occurring, and is unsure if Monday’s incident is related to the Aug. 7 outage.

“As far as I know, they never determined a concrete reason why it went down last week,” the FAA’s Gregor said.


Last week’s outage was prolonged because the technician who was needed to manually reset the system was not on site.

FAA officials had hoped that by stationing a technician there, problems would be prevented. Though a technician was at the airport Monday, the system again malfunctioned.

When the landing system shut down Monday, it cut the number of aircraft that could arrive at LAX per hour from about 65 to 46, Gregor said, and forced controllers to shift arrivals to the north runways for about 45 minutes.

The malfunction wasn’t as severe as the one that occurred last week, because it came after the busy morning rush and after the fog had dissipated.


Like last week’s outage, the landing system shut itself down after something interrupted its signal, which sends radio beams to the cockpit to tell pilots where they are in relation to the airport’s runway.

“It’s a fail-safe mechanism,” Gregor said. “It’s better to shut it down than to give erroneous information to pilots.”

The landing system is 9 years old and is typically reliable, he said. For example, the equipment flickered and went out but was quickly reset several times on the weekend of Aug. 5-6.

The union that represents LAX’s air traffic controllers has questioned whether the system’s age contributed to the outages.


Airport officials emphasized that construction on the airport’s south side, which includes the closure of the southernmost runway so workers can move it 55 feet closer to El Segundo, caused neither outage.

Hundreds of trucks ply the airfield each day just yards from the runway where the landing system is.

“There’s no linkage at all between this and the runway project,” said Paul Haney, deputy executive director of airports and security for the city’s airport agency. “They ran tests after the one last week and it was clear.”

The landing system malfunction and subsequent delays came on top of security procedures implemented after last week’s arrest in Britain of suspects who allegedly planned to blow up airliners over the Atlantic Ocean with liquid explosives.


Security checkpoints at LAX were running smoothly Monday, officials said, with few delays attributable to the ban on liquids in carry-on luggage.

LAX is experiencing its busiest summer since the Sept. 11, 2001, terrorist attacks.

Planes are running close to 100% full, leaving little room to reaccommodate passengers who miss their flights due to delays.

When officials shut down the southernmost runway for construction July 29, controllers said they could keep delays to a minimum as long as all three remaining runways were operating.


Now, the malfunctioning landing system has forced them to work with only two runways twice in one week, just days after the runway was shut down until March.

“We need all three runways functioning 24/7,” Haney said.

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System Breakdowns at L.A. International

Q&A;

Three FAA air traffic control systems malfunctioned in Southern California in the last month. Here’s a rundown of what the systems do and how they failed.

July 18: A surge protection system designed to protect backup generators from power spikes failed at an FAA communications center in Palmdale. The facility that directs high-altitude traffic lost power for two hours and controllers briefly were unable to see or talk with pilots.


July 26: The aural alarm on ground radar equipment designed to alert controllers in the LAX tower to potential collisions was shut off after the system put out a false alert, minutes before a turboprop narrowly missed a regional jet that had strayed too close to its runway. Controllers could still see airplanes on the screen.

Aug. 7 : An instrument landing system on LAX’s south airfield that sends radio beams into cockpits to help pilots orient themselves to the runway shut itself off after the signal was interrupted. FAA officials don’t know what caused the malfunction. Flights were delayed for the rest of the day.

Monday: The instrument landing system failed for a second time.