Motorcoach Loss of Control and Overturn
Santa Fe, New Mexico
March 2, 1999

NTSB/HAB-01/01 Accident No.: HWY-99-FH012, adopted 9/17/2001
[PDF Document]

Location: New Mexico State Route 475, 9 miles west of the Santa Fe Ski Basin
Date and Time: March 2, 1999, about 4:30 p.m.
Owner/Operator: Shuttle Jack, Inc.
Vehicle: 1979 Motor Coach Industries MC-9
Fatalities: Two
Injuries: Thirty-five

Accident Description: On March 2, 1999, a 1979 Motor Coach Industries MC-9, 47-passenger charter motorcoach, owned and operated by Shuttle Jack, Inc., (Shuttle Jack) of Santa Fe, New Mexico, departed the Santa Fe Ski Basin, carrying the driver, 2 adult chaperons, and 34 middle school-age children. The bus began to descend a 14-mile mountainous roadway. About halfway down the grade, the driver discovered that the vehicle's air brakes were no longer capable of slowing or stopping the bus. He noted that the brake air-pressure-gauge reading was between 90 and 120 pounds per square inch, which was the normal system operating pressure for this vehicle. During the next 3.5 miles, the driver made several unsuccessful attempts to bring the bus under control by pumping the air brakes, downshifting the automatic transmission, pulling on the emergency/parking brake valve, and shutting off the engine. Eventually, the driver lost control of the bus while rounding a left-hand curve. The bus departed the right side of the roadway, crashed into a rock embankment, and then rolled onto its left side back onto the roadway. (See figure 1.-- in PDF version) The calculated speed of the bus was 60 to 65 mph at the time of the collision. Two passengers were fatally injured, and the 35 other occupants received varying degrees of injuries.

A postaccident mechanical inspection of the bus by National Transportation Safety Board investigators revealed that the steering axle brakes were out of adjustment and the brake drums had dark spots, typically seen on overheated drums. The drive axle brakes were also out of adjustment to the extent that they were incapable of providing any braking force. The brakes on the auxiliary weight-bearing axle, commonly referred to as a "tag axle," were not operational because they were "cammed over." Both tag axle drums were worn beyond the manufacturer's accepted limits.

Probable Cause: The National Transportation Safety Board determines that the probable cause of this accident was the poor condition of the motorcoach brakes due to the lack of an effective motor carrier vehicle maintenance and inspection program. Contributing to the accident was the lack of State oversight of the motor carrier's intrastate operations.