MEXICO CITY -- A tire explosion, not a bomb, caused a Mexicana Airlines jetliner to crash in March, killing 166 people in the worst disaster in Mexican aviation history, the Communications Ministry said Thursday.
A report by the Aviation Accident Commission since the March 31 accident said the wings and body of the Boeing 727 began breaking up at 15,000 feet altitude as the pilot fought to maintain control of the craft while all his control systems disintegrated, the official news agency Notimex said.
Within minutes after the emergency began, the tail of the plane with the three engines broke off and crashed on a hill, while the main body of the aircraft smashed into a deep ravine, Notimex said.
The official report, which will be shared with civil aeronautics agencies around the world, said evidence showed one of the rear tires exploded after the landing gear had been retracted because of the 'overheating of the middle part of the wheel.'
'The explosion of a wheel in flight is not a frequent incident but it has occurred in other parts of the world and even in Mexico,' the report said, adding that other times 'the consequences were not as fatal.'
Mexicana Airlines flight 940 to Los Angeles, with stopovers in Puerto Vallarta and Mazatlan, exploded and crashed 14 minutes after takeoff from the Mexico City airport, killing all aboard, including 158 passengers and eight crew members.
Pilots had originally blamed the crash on a bomb, but the Communications Ministry report said there were no signs of any explosive in the wreckage.
'The examinations carried out by experts ... convincingly demonstrated there is no evidence of the presence of any explosive devices,' the report said.
The plane crashed in the rugged Sierra Madre mountans near the mining town of Maravatio, 80 miles west of Mexico City.
'The explosion of the tire provoked the rupture of different tubes, principally in the fuel, hydraulic, electricity and air ventilation systems,' the report said.
'The fire produced by the explosion of the tire was whipped by wind that entered with great force because of the plane's velocity, making the plane lose power,' it said.
The report said the intense heat melted the rear fuselage under the tail of the aircraft.'
The report said the blowout may have been caused by a defect in the tire, overheating or damage sustained during takeoff or landing.
The commission has ordered Mexicana airlines to establish preventive maintenance in the inspection and upkeep of landing gear of all Boeing 727 of the type that crashed.