On Interstate 95 (I-95) near Fairfield, Connecticut, two consecutive accidents occurred within 11 minutes in the early morning hours of January 17, 2003. About 4:50 a.m., a 1996 Freightliner tractor flatbed semitrailer, loaded with five portable compressor units, was involved in a nonfatal multivehicle accident. The truck was traveling in a work zone on I-95 north, near milepost 26.6, at a driver-estimated speed of 50 mph, when it slid out of control approximately 1,150 feet south of the exit 24 southbound off-ramp. The vehicle entered the median, overturned and overrode the portable concrete barrier, and collided with a southbound 1997 Dodge Avenger sedan. A southbound 2001 Freightliner tractor/refrigerated trailer combination unit struck the Dodge sedan and then struck the 1996 Freightliner tractor. The three vehicles came to rest blocking the southbound lanes of the highway. During the accident sequence, the flatbed semitrailer separated from the 1996 Freightliner tractor. The semitrailer came to rest perpendicular to the roadway, straddling the portable concrete barrier and partially obstructing the left lane of I-95 north.
At 5:01 a.m., a 1999 Chevrolet Tahoe sport utility vehicle-occupied by nine students from Yale University and traveling north in the left lane-collided with and underrode the left side corner of the 1996 Freightliner tractor flatbed semitrailer. Following the impact, the Chevrolet disengaged from the semitrailer and entered the median, skidded along the concrete barrier, and came to rest about 450 feet northeast of the semitrailer. The driver and three passengers in the Chevrolet were fatally injured. The surviving occupants were seriously injured.
Witnesses reported that at the time of the accidents, light snow was falling, the roads were wet and icy, and snow covered the roadway shoulders.
The National Transportation Safety Board determines that the probable cause of the 4:50 a.m. accident was the 1996 Freightliner's loss of lateral stability, probably due to the operator driving too fast for conditions and to the presence of black ice on the roadway. Contributing to the accident were the inadequate roadway treatment provided by the Connecticut Department of Transportation in response to inclement weather and also its failure to provide a median barrier capable of preventing crossovers by heavy vehicles. The probable cause of the 5:01 a.m. accident was the failure of the Chevrolet driver to identify and avoid the flatbed semitrailer due to fatigue, in conjunction with the distraction from the median crossover accident in the southbound lanes.
The following safety issues were identified in this investigation:
- Adequacy of snow and ice treatment strategies,
- Lack of specific guidance on the use of high-performance median barriers,
- Placement of portable concrete median barriers, and
- Need for primary seat belt laws for all seating positions.
As a result of this accident investigation, the Safety Board makes recommendations to the Federal Highway Administration, the Connecticut Department of Transportation, and the American Association of State Highway and Transportation Officials. The Safety Board reiterates a recommendation to the Governor and legislative leaders of Connecticut.