NTSB Animation - Multivehicle Collision - Milk Tank Combination Vehicle and Stopped Traffic Queue

This animation depicts the sequence of events during a multivehicle collision that occurred in Phoenix, Arizona on June 9, 2021, at 10:07 pm mountain standard time.
The animation begins with an overall map showing the location of Phoenix in Arizona, overlayed with an image of a Freightliner Cascadia truck tractor in combination with a Walker stainless tank trailer, like the combination vehicle involved in the crash. Next, a regional map of Phoenix shows the traveling route of the truck transporting milk from Stotz Dairy on the west side of Phoenix to the United Dairymen of Arizona cooperative plant on the east side of Phoenix. The crash location on State Route 202 is also indicated.

A map at higher magnification shows the crash location and the locations of two overhead dynamic message signs. Photographs of the two dynamic message signs are shown, along with the message that was displayed on both signs at the time of the crash: “LAW ENFORCEMENT AT PRIEST EXPECT TO STOP,” which alternated with dynamic travel times. The first message sign is located about 3 miles west of the collision location, and the second message sign is about 330 feet east of the collision location. The location of Priest Drive is also shown on the map.

A map at higher magnification shows the local geometry of the roads near the crash location on State Route 202, which was just east of Exit 4 to 52nd Street. The map is replaced with an overhead photograph of the eastbound 5 travel lanes, with the right lane where the collision occurred highlighted.

Forward-facing Lytx DriveCam video shows the truck-tractor passing the 52nd Street exit, approaching visible red brake lights of slowing and stopped traffic ahead that
had formed a queue in the right lane. The video is stopped just before the truck collides with the end car in the queue.

The collision sequence of the vehicles involved is described using three-dimensional vehicle models. The first graphic shows eight vehicles in the right lane in order: the Freightliner Cascadia truck tractor in combination with a Walker stainless tank trailer; a gray Ford; a black Toyota; a gray Chevrolet SUV; a red Nissan; a white Dodge; a black Mercedes, and a white Lexus. Each passenger vehicle is circled and labeled as they are listed.

A series of stop-motion graphics then illustrate the sequence of the collision, but the illustration is not an exact reconstruction. Also, the graphics do not attempt to replicate the weather or lighting conditions at the time of the crash. The view is generally from the right rear of the truck. The collision sequence is followed by an image showing the final rest of all 8 vehicles involved. As a result of the crash, 4 persons were fatally injured, and 11 persons were transported to the hospital; the truck driver was not injured.

Two photographs illustrate the condition of the vehicles on the morning after the collision. The first photograph is a view looking westbound, with the Chevrolet and truck tractor in the foreground and the Nissan, Ford, Toyota, Mercedes, Dodge and Lexus visible in the background. The second photograph is a view looking eastbound, with the Lexus, Dodge, Mercedes, Ford and Toyota in the foreground and the truck tractor and Chevrolet in the background.