Optimum Braking, Stability and Structural Integrity for Longer Truck Combinations

The need for operating double and triple trailer combinations has long been recognized. One of the most troublesome questions was braking stability – could longer combinations operate within the same degree of controllability as existing equipment? Stopping performance and stability were studied under controlled conditions of wet and dry roads and various loadings with double and triple combinations. The Utica tests demonstrated that longer combinations, commonly referred to as “double 40s and triple 27s,” when made from properly maintained equipment in current use, achieved braking, stability, and structural integrity characteristics comparable to the shorter combinations – the “single 40s and double 27s.” Modifications to the brake system will improve both stopping distance and stability and allow a greater latitude in loading.