It is no coincidence that Rough Terrain Forklifts or Telehandlers turn over sideways when they fail. Untrained or poorly trained users do not realize that the Telehandler has many of the same characteristics found in cranes. A standard forklift has forks or other attachments on a carriage that is lifted up a mast. They have a fixed capacity as long as the load is within the fork load center. A Telehandler on the other hand has a telescoping boom and when it extends, increasing the radius, its capacity is reduced. It has a Capacity Chart like a crane showing what the capacity is as the radius increases. When the boom is extended it also must be setup level, on tires or stabilizers, like a crane when operated. Some Telehandlers have an oscillating axel that allows them to travel on rough terrain but it must be locked in position using a hydraulic cylinder when setup and extending the boom. The specific cause of the accident is not known at this time, but the pictures show that they turned over sideways. There are several things that would cause this type of turnover. Either the Telehandler was not setup level or the stabilizers were not set or the axil was not locked, any of which would cause it to turn over sideways.