Commercial tractor-trailers are equipped with air brakes. It is critical to keep the brakes in adjustment. Reconstruction engineer know that many accidents are the result of poorly adjusted slack adjustors and is usually the starting point of a commercial truck accident investigation.
The braking system of commercial tractor-trailers utilize compressed air rather than hydraulic fluids as does cars and light trucks. The benefit of using compressed air is that it allows the truck to be connected or disconnected quickly from the trailer without running the risk of contaminating the air brake system. As you can imagine, connecting and disconnecting a hydraulic fluid system would be more difficult and more time consuming.
If air were introduced into a hydraulic system, it would deteriorate the overall braking efficiency of the vehicle. Although air brake systems are used instead of hydraulic systems on tractor-trailers for safety reasons, they are not free from being susceptible to problems that may result in inadequate braking.
The most common cause of a braking problem stems from a lack of maintenance or calibration. A truck/tractor with poorly maintained or calibrated slack adjusters required more distance and time to stop the rig. In some cases this can cause trailer swing-outs and even jackknifing.
Other problems may result from mechanical defects or even improper repairs. The Federal Motor Carrier Safety Regulations require motor carriers to regularly inspect, repair and maintain its motor vehicles to ensure that they are in a safe operating condition at all times.
Our reconstruction engineers gather critical information about a vehicle's braking ability/efficiency after each truck/tractor investigation.
The information gathered about the overall combination of parts and an inspection of the accident scene allows the accident reconstruction engineer to calculate the speed the truck/tractor was traveling at the beginning of tire lock-up. The overall braking efficiency of the tractor-trailer braking system is determined from examination of the slack adjustors. Truck/tractor investigation take into account not only the condition of the air brake system, the vehicle's load, driver's interaction and roadway environment but also federal regulation governing the operation of the vehicle.
A good understanding of how the truck braking system works is essential in reconstructing a traffic accident involving a commercial truck/tractor. Identifying the cause of a braking problem is a tedious task that requires the expertise of highly trained professionals.
Seek out the help of an engineer with expertise and training in commercial air brakes to determine the condition of air brakes of a truck involved in an accident. They will be able to answer questions about maintenance, calibration, repairs, defects, speed, and braking. This information is valuable to clients and attorneys for making informed decisions about which direction to go with their case.
For information about traffic safety and federal regulations visit the National Highway Traffic Safety Administration website.
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