I agreee that operator error is most likely to blame. But there could be other factors as well. What type of floor surface are we talking about? How smooth is it? remember only one wheel drives and stops the truck. The wheel can also be subject to improper adjustments of the casterwheel. If there isnt the right amount of preload on it, then the drive tire may not have the proper amount of load, and could cause a slipperly condition, especially, if the "swing" of the truck was in a direction that aided in unloading the drive wheel, thereby limiting braking strength.

These types of units are mainly designed to use directional "plugging" to stop and or change directions. Should the operator(s) use the deadman brake to stop the truck all the time, this could cause premature wear to the brakes also making the brakes less effective.

In effect, anytime you are thrown form a lift truck, (stand up or otherwise) you are travelling too fast for the conditions. Add to this a imporperly maintained truck or super smooth floors, and you will have a recipe for disaster.

Anytime you are operating a stand up narrow isle truck, and you are in a situation of loss of control, STAY IN THE TRUCK AT ALL COSTS! Otherwise, the operator will get hurt.

Doc.