Incident Overview
On an approach to Mexico-Benito Juarez International Airport, a Learjet 45 crashed after losing control following an encounter with wake turbulence generated by a preceding Boeing 767-300. The aircraft disintegrated upon impact on Monte Pelvoux and Ferrocarril de Cuernavaca Avenues, resulting in the deaths of all nine occupants and seven individuals on the ground. Approximately 40 people on the ground sustained injuries, some serious. The crash also damaged several buildings and destroyed about 20 cars.
Sequence of Events
The Learjet 45 had completed an uneventful flight from San Luis Potosí. The crew was cleared to the MATEO VOR and for an ILS/DME approach to runway 05R. Air traffic control (ATC) initially instructed the crew to increase speed to 220 knots. The Learjet was following a Boeing 767-300 operating as Mexicana Flight 1692 from Buenos Aires. ATC instructed the Boeing 767 to reduce speed to 160 knots to maintain separation with a preceding Airbus A318. At 18:41, the Learjet was further instructed to slow to 150 knots indicated airspeed. At 18:42, the Boeing 767 crossed MATEO VOR at a ground speed of 224 knots, with the Learjet 8 nautical miles (NM) behind at 272 knots ground speed. At 18:44, ATC instructed Mexicana 1692 to slow to minimum approach speed. At that time, the Learjet was crossing MATEO VOR at 262 knots ground speed, approximately 5.7 NM behind. The controller then instructed the Learjet crew to reduce speed to 180 knots. Although the crew acknowledged, they took 16 seconds to act. Separation had decreased to 3.8 NM, and the Learjet entered the wake turbulence of the Boeing 767. Control was lost, and the aircraft entered an uncontrolled descent, crashing onto the streets below.
Probable Cause
The official investigation identified the probable cause as: "Loss of control at low altitude and subsequent impact of the aircraft with the ground after it encountered wake turbulence caused by a preceding aircraft." Contributing factors included: lack of adequate crew training on the Learjet 45, delay by the crew in reducing approach speed, lack of ATC correction of the excessive approach speed, fatigue accumulated by ATC, grant of flight capacity combined with administrative problems and probable corruption, and insufficient monitoring of the aircraft operator for maintenance and operation.
Occupants and Casualties
All nine occupants aboard the Learjet 45 were killed, including notable passengers: Juan Camilo Mouriño Terrazo, Interior Minister; José Luis Santiago Vasconcelos, General Attorney; and Miguel Monterrubio Cubas, Director for Social Communication. Seven people on the ground also lost their lives, and 40 others were injured, some seriously.