A failure of Pierce Manufacturing’s ALL STEER system was identified by Massachusetts State Police as the suspected cause of an April rollover of Framingham Engine 7, a 2001 Pierce Quantum pumper, that injured four firefighters. The investigative finding is disputed by Pierce and its parent company, Oshkosh Corporation.
An 18-page report of the state police investigation said the four firefighters were hurt because they failed to wear seatbelts. “All of them incurred injuries as a result of being tossed around the interior of this vehicle with their unsecured Scott-Packs, extrication tools or whatever else that wasn’t secured in the cab,” the report said.
The driver, David Carroll who had minor injuries and has since retired, insisted he was wearing his seatbelt, according to Framingham Fire Chief Gary Daugherty. “Knowing him,” he said, “I’d be surprised if he wasn’t.”
Seatbelt Policy Missing
The other three firefighters, who were still in therapy as of the end of August, admitted they were not wearing seatbelts, according to the chief, who said Massachusetts firefighters and police officers are exempt from the state’s motor vehicle seatbelt requirement.
Daugherty said he was told the fire department had a policy requiring the use of seatbelts when he joined it less than two years ago. However, he said, following the accident, nobody could find the policy. A mandatory seatbelt policy has since been established.
As a precaution following the accident, the department disabled ALL STEER systems on two other Pierce apparatus it owns – Engine 1, a 2000 Quantum pumper, and Ladder 3, a 1998 Quantum 105-foot aerial.
Pierce ALL STEER is an electronic allwheel steering system designed to enhance maneuverability and improve the turning radius by as much as 30 percent, allowing heavy-duty fire trucks to navigate tight city streets. It was the subject of recall notices in 2001 and 2004 when the company notified government officials of defects discovered after malfunctions were reported.
Framingham officials have been conducting a legal review of the state police investigative report, which they declined to make available, and Daugherty said action against Pierce is possible.
Fire Apparatus & Emergency Equipment magazine obtained the investigative report from the Massachusetts State Police through a public records request. Oshkosh Corporation issued a brief statement in response to an inquiry from the magazine in late August.
“Pierce Manufacturing has no comment because we have not seen the Massachusetts State Police report regarding the April 10, 2010 incident involving the Framingham Fire Department and a Pierce 2001 pumper,” the Oshkosh statement said. “Pierce Manufacturing conducted its own investigation of the incident and found nothing to suggest that the Pierce ALL STEER system did not function properly.”
The state police said ALL STEER was identified as the suspected cause by the process of elimination.
“None of the physical evidence has shed any light on what the triggering event was to the causation of this crash,” the state police report said. “Nevertheless and equally important, employing the same physical evidence, it was possible to eliminate the usual suspects that are generally the most common cause of these types of crashes.”
Driver Error Eliminated
The weather at the time of the accident, according to the report, was sunny, the road surface was dry, traffic volume was light, no animals or pedestrians were in the area and the fire engine was returning to quarters and going “around 32 miles per hour when it inexplicably, unexpectedly and suddenly veered to the left.”
The state police eliminated driver error as a possible cause.
“There isn’t a single scintilla of evidence that suggests that the operator of the fire engine was speeding, making any improper steering motion or anything that contributed to the causation of this crash,” the report said. “By sheer deductive logic elimination, it was determined that the triggering event that caused this crash was that the fire engine had some type of mechanical malfunction.”
The state police said their investigation determined the brakes were not a factor and the truck did not have a blowout. Weight shift was also eliminated.
“The only other possible mechanical malfunction is steering,” the report said. “At this time it is suspected that the Oshkosh all-wheel steering failed. This resulted in the fire engine going wildly and violently out of control… the right rear steering control rheostat did not ‘zero out.'”
Oshkosh was contacted by the state police about a possible rheostat malfunction, the report said, and “it was determined this COULD HAVE caused the rear steering to inappropriately engage.”
Flaws In Analysis
On May 14, Massachusetts State Police said they received a report from Pierce on the company’s investigative findings. The author of the state police report said he “found several flaws” in the Pierce analysis, which appears to have focused on brakes as a possible cause.
Both investigations found missmatched brakes on Framingham’s Engine 7. “The left front airbrake canister was a type 24 short stroke, and the right was a type 30 short stroke,” the state police report said. “While having missmatched brakes is a serious violation of Title 49 of the Federal Commercial Motor Vehicle Safety Code and is an outof- service violation, it was determined by actual test skids… that the miss-matched brakes were not a factor in this crash.”
Moreover, the state police said, a download of the engine control module (ECM) “did not record a brake application during the crash. A check of the ABS sensors determined that they were functioning and would have been imaged in the ECM had they been applied any time during the crash.”
The author of the state police report, Sgt. William H. Pultar, said one of the tire marks at the crash site was particularly significant. He wrote: “As a result of this mark being burnt into the pavement, which means it took a significant amount of heat to generate this mark, it is the belief of this expert that this evidence was caused by the rear tires suddenly and violently going into a ‘crab’ mode.”
Crab mode is one of several different steering modes built into the ALL STEER system for improved maneuverability. The driver is supposed to select the desired mode based on driving conditions.
For maximum maneuverability in slow speed operation (up to 10 mph), according to Pierce, ALL STEER has a fire-ground coordinated mode and a fire-ground crab mode. The fire ground-coordinated mode provides the sharpest turning possible, the company said, and the fire-ground crab mode allows the vehicle to move sideways in a diagonal manner.