Technicians were working on the radar at Burbank Airport the day a small plane flew into the San Gabriel Mountains and crashed, killing two men, the Federal Aviation Administration said.
Federal investigators are trying to determine whether the work on the radar system contributed to last month's crash of the Cessna 172 in the Angeles National Forest northeast of Los Angeles. A preliminary investigation showed that a controller monitoring the craft from Burbank-Glendale-Pasadena Airport put the plane on a course toward the mountains, according to the National Transportation Safety Board.
Federal officials said Friday that the controller was working with radar that was being upgraded with computer software that tells controllers a plane's altitude, airspeed and aircraft type.
"During the day of the crash, technicians were upgrading the radar," said FAA spokesman Russ Park. "It was strictly a software change to a system that allows a little bit more data recording capability."
During the upgrade the computers were switched back and forth several times, Park said. He refused to elaborate.
"When you put a new system on line, you use it for a while to see if it's OK, and if there are any problems you switch back to the old system," he said. "That happened several times during the day."
Park said he was not certain whether the changeover was completed before the 7:30 p.m. crash on Oct. 16. But even if it was not, he said, "there's no interruption to the radar picture when you switch from one over to the other and back."
Nonetheless, the NTSB is investigating whether the radar might have contributed to the crash.
"We're looking into the radar and computer system and whether it was functioning properly," NTSB spokesman Mike Benson said Friday in Washington. "We're also looking into the controller's activities and the level of communication between controllers in the period leading up to the accident."
Killed in the crash were flight instructor Allen Hart, 24, of Florida and student pilot August Henschell, 24, of Austria. They had taken off from Van Nuys Airport and were bound for Santa Monica Airport.