Operators of trucking fleets have been warned by Australia’s National Heavy Vehicle Regulator of the safety risks posed by dirty truck parts during visual safety inspections. Dirt on truck parts might be obscuring dangerous flaws, it stated.
Inspections of heavy vehicles are needed both to check that the truck is roadworthy and also that it complies with the Heavy Vehicle (Vehicle Standards) National Regulation.
The regulator reminded truck operators and their maintenance personnel to ensure that periodic cleaning is done so that good visual inspections can be made. And, if a vehicle is not clean, then it should be cleaned. The regulator also similarly warned inspectors who carry out annual checks.
It said trucks and truck parts need to be clean, free of grime, dirt, mud and lubricants.
A failure to clean the vehicle can hide or disguise problems, leading to a failures in repair and preventative maintenance. Details of a fatal crash caused by dirty truck parts can be found after the banner.
Deceased: truck driver Stephen Ross Brown
A failure to clean truck parts prior to a visual inspection can be fatal.
It certainly was for truck driver Stephen Ross Brown.
Brown was driving for Goldmix Stockfeeds near Cloyna, a town in a somewhat remote part of the state of Queensland. He was driving a prime mover and semi-trailer combination and was carrying a load of grain. At 100km/h (62 mph) the suspension suddenly catastrophically failed. According to witnesses (including Brown who survived for a time after the crash), there was a loud “bang,” Brown lost control of the steering, the truck veered off the road to the right at speed and crashed into a tree.
The crash nearly ripped off one of Brown’s legs while injuring his other leg and causing damage to his pelvis.
He was trapped for 40 minutes before being airlifted by helicopter to hospital. Tragically, he later died. Brown had unknown deep vein thrombosis (a blood clot deep in the body) owing to his obesity (caused in part by a truck driver’s sedentary lifestyle). The crash caused the blood clots to mobilize within his body, where they traveled to his lungs and killed him.
Witnesses to the Queensland Coroner’s Court gave a series of contradictory statements about the company’s repair and maintenance schedule and the standard of documentation. However, a review by the National Heavy Vehicle Regulator accepted that compliance with maintenance and servicing schedules was acceptable.
Fatigue factured leaf spring
A post-accident inspection of the wreck was carried out. A police-employed mechanic noted that two of the suspension leaf springs within the truck’s right front suspension had sheared/snapped off. The steer axle, right leaf spring, was broken next to the front chassis hanger and locating pin. There was wear and tear damage. The second helper leaf spring was fatigue-fractured in the same area. The police mechanic told the coroner that failure could cause the steer axle to move rearwards on the right-hand side, causing a sudden right-ward veering of the truck and that it would be very hard for the driver to control the rig. The police mechanic also noted the presence of grease in the area and commented that, if there were no grease, then a person would see the fracture in the first leaf spring if it were a complete fracture.
Independent forensic mechanical engineer Terrence Casey examined the failed parts along with photographs of the scene and vehicle. He concluded that the leaf springs had failed because of the presence and growth of fatigue cracks. Casey added that the primary leaf spring had failed before the secondary leaf spring and that the vehicle had continued to work subsequent to the failure of the primary leaf spring. He testified that when the main spring fails it doubles the stressors on the second leaf spring. Casey also noticed grease in the area and considered that it was likely the fatigue fractures went unnoticed because of that grease. He added that, if it had been cleaned then the failure of the main spring leaf may have been found. He also concluded that complete failure of the leaf springs happened before the truck crashed into the tree; it was the failure of the spring leaves that caused the truck to veer out of control to the right.
In giving his findings, the coroner noted the conclusions of two separate and independent experts that grease may have hidden the presence on fatigue cracks in the leaf springs. The coroner recommended that National Heavy Vehicle Regulator should consider whether there needs to be enhanced guidelines so that people who are inspecting heavy vehicles are aware of the risks posed by dirty trucks.