National Transportation Safety Board
Highway Accident Report

PB93-916201
NTSB/HAR-93/01 (a 61-page report)
Adopted: April 13, 1993

Mayflower Contract Services, Inc. tour bus plunge from Tramway Road and overturn crash near Palm Springs, California, July 31, 1991

EXECUTIVE SUMMARY

   "At 3:24 p.m. on July 31, 1991, a 1989 72-passenger school bus operated by Mayflower Contract Services, Inc., was traveling westbound on undivided, two-lane Tramway Road from the Palm Springs (California) Aerial Tramway parking lot. On board the bus were 45 girl scouts and 8 adult advisors. During the descent, the bus increased speed, left the road, plunged down an embankment, and collided with several large boulders. The bus driver and 6 passengers were killed, 47 passengers were injured.
    "The National Transportation Safety Board determines the probable cause of this accident was the loss of speed control while descending Tramway Road because of the bus driver's use of improper driving techniques for mountainous terrain. Contributing to the accident were the out-of-adjustment brakes, which had not been detected in the Mayflower Contract Services, Inc., maintenance reporting and inspection procedures.

"The safety issues discussed in this report include the adequacy of:

"bus driver training in mountain driving techniques and proper transmission operation in mountainous terrain,

"motor carrier inspection and maintenance programs,

"State regulations on school bus inspection and maintenance procedures,

"school bus occupant protection, and

"traffic control devices on Tramway Road and traffic control standards applicable to private roads.

   "As a result of its investigation, the Safety Board issued safety recommendations to the Federal Highway Administration, the State of California, the California Department of Education, the California Highway Patrol, the Mount San Jacinto Winter Park Authority, the National Committee on Uniform Traffic Laws and Ordinances, the American Association of State Highway and Transportation Officials, the National Association of State Directors of Pupil Transportation Services, the General Motors Corporation Allison Transmission Division, and Mayflower Contract Services, Inc."

PROBABLE CAUSE

   "The National Transportation Safety Board determines the probable cause of this accident was the loss of speed control while descending Tramway Road because of the bus driver's use of improper driving techniques for mountainous terrain. Contributing to the accident were the out-of-adjustment brakes, which had not been detected in the Mayflower Contract Services, Inc., maintenance reporting and inspection procedures."

RECOMMENDATIONS

"As a result of its investigation, the National Transportation Safety Board made the following recommendations:

-- to the Federal Highway Administration:

"Adopt the National Highway Traffic Safety Administration definition of trafficway to ensure uniformity of traffic control devices on public and private roads. (Class II, Priority Action) (H-93-10)

"In cooperation with the States, require that, where appropriate, the Manual on Uniform Traffic Control Devices or each State traffic manual applies to trafficways to ensure uniformity of traffic control devices on public and private roads. (Class II, Priority Action) (H- 93-11)"

-- to the State of California:

"Amend the California Vehicle Code to include the National Highway Traffic Safety Administration definition of trafficway to ensure uniformity of traffic control devices on public and private roads. (Class II, Priority Action) (H093-12)

"Require that the California Traffic Manual sections regarding traffic control devices apply to trafficways to ensure uniformity of traffic control devices on public and private roads. (Class II, Priority Action) (H-93-13)"

-- to the California Department of Education:

"Expand the school and tour bus driver training curriculum to include automatic transmission upshift characteristics and proper transmission operation in mountainous terrain. (Class II, Priority Action) (H-93-14)

"Develop a specific curriculum for the initial and the recurrent training of school and tour busdrivers in mountain driving techniques and require those bus drivers to complete this training before driving in mountainous terrain. (Class II, Priority Action) (H-93-15)"

-- to the California Highway Patrol:

"Require that motor carriers verify that a vehicle condition report is submitted promptly by each school and tour bus driver after operating a vehicle. (Class II, Priority Action) (H-93-16)

"Require that all school and tour bus air/mechanical brakes with manual slack adjusters be fully adjusted at each required inspection. (Class II, Priority Action) (H-93-17)"

-- to the Mount San Jacinto Winter Park Authority:

"Bring all traffic control devices on Tramway Road into conformance with the California Traffic Manual. (Class II, Priority Action) (H-93-18)"

-- to the National Committee on Uniform Traffic Laws and Ordinances:

"Adopt the National Highway Traffic Safety Administration definition of trafficway to ensure uniformity of traffic control devices on public and private roads. (Class II, Priority Action) (H-93-19)"

-- to the American Association of State Highway and Transportation Officials:

"Adopt the National Highway Traffic Safety Administration definition of trafficway to ensure uniformity of traffic control devices on public and private roads. (Class II, Priority Action) (H-93-20)"

-- to the National Association of State Directors of Pupil Transportation Services:

"Advise your membership of the facts and circumstances of this accident and encourage them to incorporate automatic transmission upshift characteristics and proper transmission operation in mountainous terrain, where appropriate, into each school jurisdiction bus driver training curriculum. (Class II, Priority Action) (H-93-21)

"Encourage your membership to require that all school and tour bus air/mechanical brakes with manual slack adjusters be fully adjusted at each required inspection. (Class II, Priority Action) (H-93-22)"

-- to Allison Transmission Division:

"Furnish an advisory label with newly manufactured Allison automatic transmissions that have the automatic upshift feature. Recommend to transmission purchasers that the label be mounted on each vehicle where it is clearly visible to the bus driver. (Class II, Priority Action) (H-93-23)"

-- to Mayflower Contract Services, Inc.

"Expand the school and tour bus driver training curriculum to include automatic transmission upshift characteristics and proper transmission operation in mountainous terrain. (Class II, Priority Action) (H-93-24)

"Institute procedures to verify that a vehicle condition report is submitted promptly by each bus driver after operating a vehicle. (Class II, Priority Action) (H-93-25)

"Require in your inspection and maintenance operations that all school and tour bus air/mechanical brakes with manual slack adjusters be fully adjusted at each required inspection. (Class II, Priority Action) (H-93-26)"