Preventable or not?


John Doe heard the kingpin snap into place and visually inspected the connection. Obviously something wasn’t right, but should Doe be charged with a preventable?

John Doe showed up on time in the yard, sipping hot coffee with a big bag of Gummy Bears in his left hand. He walked to the door of his tractor, climbed in, fired her up, warmed the engine for a couple of minutes, and then pulled toward a nearby line of trailers.

Doe drove over to the trailerload of ice cream he had been assigned to haul, backed under it until the kingpin audibly smacked into the fifth wheel and applied the parking brake. He got out, cranked up the old, wheeled landing gear and then did a brief walkaround inspection.

Satisfied that he was ready to go, Doe then depressed the parking brake valves, slipped a tape into his cassette player, snagged a piece of second gear and slowly headed toward the front gate. He stopped at the gate, waited for traffic to clear, and then let up on the clutch, this time a little more abruptly, so he could get into his lane and accelerate before traffic approaching from the left caught up.

As Doe worked to complete his turn, he suddenly felt a change in his rate of acceleration. He glanced in his mirrors and realized the side of his trailer was filling them up. It had broken loose!

Doe pulled to the side of the road and applied his parking brake, and then watched, frozen in horror, as the trailer rolled right across the road on its landing gear wheels! Once the wheels hit the soft earth of the cornfield there, the trailer stopped abruptly and rolled over.

The safety director presented Doe with a warning letter. Doe challenged it, believing the fifth wheel or kingpin must have been the problem. “The hook-up felt normal and sounded solid,” he claimed.

So the safety director asked Doe if he had locked the trailer brakes and pulled forward to test the security of the fifth wheel’s grasp of the trailer kingpin. He sheepishly admitted he had not. Had he viewed the situation to see that the pin was securely locked into the jaws? He said he had not. After the trailer was recovered, the safety director ordered the maintenance shop to carefully inspect the kingpin and fifth wheel in case Doe had been the victim of a mechanical problem. An experienced technician could find no problem and demonstrated the fifth wheel’s ability to tightly grasp the dented trailer’s hitching post just to prove the point.

Doe still asked the National Safety Council’s Accident Review Committee to review, believing he had hitched properly. They ruled the accident fully preventable, noting that a complete pre-trip verification of actual fifth wheel engagement is essential to operating.