The crash occurred on Sunday, October 23, 2016, in dark conditions, about 5:16 a.m. Pacific daylight time, when a motorcoach ran into the rear of a stopped combination vehicle near mile marker 32.5 in the westbound lanes of Interstate 10 (I-10), outside Palm Springs, California.
About 5:07 a.m. (9 minutes before the crash), the California Highway Patrol (CHP) initiated a traffic break for both eastbound and westbound traffic on I-10 in support of utility work that was being performed about 1.5 miles west of the crash location. (A traffic break is a method of temporary traffic control that is used to slow or stop traffic, most typically to allow for completion of construction activities.) At that time, a 2015 International Prostar truck-tractor in combination with a 2012 Utility semitrailer, operated by Tri-State Collision LLC, was traveling westbound on I-10. The combination vehicle stopped when it reached the traffic queue that had formed as a result of the break. About 5:14 a.m., after a traffic break that lasted about 7 minutes, the CHP released westbound traffic to start moving again. Despite the release, however, the combination vehicle remained stopped in the center-right lane of the four-lane westbound roadway and, according to witnesses, was stationary as westbound traffic resumed normal flow.
About 2 minutes after the traffic break ended, a 1996 Motor Coach Industries International Inc. (MCI) 47-passenger motorcoach, operated by USA Holiday, was traveling at highway speed on westbound I-10 in the lane in which the combination vehicle was stopped. The motorcoach, which was occupied by a 59-year-old driver and 42 passengers, struck the rear of the semitrailer, intruding about 13 feet into the semitrailer and pushing the combination vehicle 71 feet forward before coming to a stop. As a result of the crash, the bus driver and 12 passengers died, and the truck driver and 30 passengers were injured.
We determined that the probable cause of the Palm Springs, California, crash was (1) the California Department of Transportation’s inadequate transportation management plan for the traffic break, which resulted in a hazardous traffic situation in which law enforcement did not detect the combination vehicle’s lack of movement after the traffic break ended and the bus driver did not receive any advance warning of potential traffic stoppage ahead; (2) the truck driver’s not moving his combination vehicle after the traffic break ended, most likely due to his falling asleep as a result of his undiagnosed moderate-to-severe obstructive sleep apnea; and (3) the bus driver’s lack of action to avoid the crash due to his not perceiving the combination vehicle as stopped, as a result of his fatigue and the fact that he did not expect to encounter stopped traffic.
We made new recommendations to the Federal Highway Administration, the FMCSA, Tri-State Collision LLC, the American Trucking Associations, the Owner-Operator Independent Drivers Association, the Commercial Vehicle Safety Alliance, the International Association of Chiefs of Police, and the National Sheriffs’ Association. We reiterated recommendations to the FMCSA, the National Highway Traffic Safety Administration, Daimler Trucks North America LLC, Fuji Heavy Industries USA Inc., Hino Motors Manufacturing USA Inc., MCI, Navistar Inc., PACCAR Inc., Van Hool NV, and Volvo Group North America LLC. We reiterated and reclassified one recommendation to the FMCSA.
