Incident Overview
AeroMéxico Flight AM498 was operating a scheduled passenger service from Mexico City to Los Angeles, with intermediate stops at Guadalajara, Loreto, and Tijuana. The aircraft, a DC-9 named 'Hermosillo', departed Tijuana Airport at 11:20 local time and proceeded toward Los Angeles at Flight Level 100.
Sequence of Events
At 11:44, Coast Approach Control cleared the flight to descend to 7,000 feet. Three minutes prior to this clearance, a Piper PA-28-181 Cherokee with registration N4891F departed Torrance Airport for a visual flight rules (VFR) journey to Big Bear, California. The general aviation aircraft carried one pilot and two passengers.
The Piper pilot turned toward the Paradise VORTAC on an easterly heading and entered the Terminal Control Area (TCA) without obtaining clearance from air traffic control, in violation of FAR Part 91.90. At 11:47, the AeroMéxico pilot reported being level at 7,000 feet to LA Approach Control. The controller subsequently cleared Flight 498 to depart Seal Beach on a heading of 320 degrees for the ILS runway two-five left final approach course.
At 11:51:04, the approach controller instructed the flight to reduce airspeed to 190 KIAS and cleared it to descend to 6,000 feet. Approximately at 11:52:09, the two aircraft collided over Cerritos at an altitude of roughly 6,560 feet.
Impact and Aftermath
The Piper struck the left side of the DC-9's horizontal and vertical stabilizers. The horizontal stabilizer sliced through the Piper's cabin before separating from the tailplane. Both aircraft tumbled out of control to the ground. The resulting wreckage and post-impact fires destroyed five houses and damaged seven others, killing fifteen individuals on the ground. Weather conditions were clear with reported visibility of 14 miles.