The angle of deflection of a loaded boom from the horizontal plane and measured from the base of the boom is referred to as?

• A. Boom Angle
• B. Boom Tilt
• C. Angle of Reach
• D. Elevation

Answer: (A)

The main idea here is how the crane’s arm is oriented relative to the ground. The term that matches “the angle of deflection of a loaded boom from the horizontal plane, measured from the base” is boom angle. This describes how much the boom tilts upward from level, with the base as the reference point.

This matters because the boom angle changes the geometry of the lift—the vertical and horizontal components of the load depend on how steep or shallow the boom is, which in turn affects reach, height, and lifting capacity. When the boom is near horizontal, reach is greater but lift height is lower; as it tilts upward, the lift height increases and the horizontal reach decreases.

Other terms don’t fit this specific definition: boom tilt would refer to a different axis or type of tilt, angle of reach implies a different measure, and elevation is used in other contexts to describe vertical angle of the load line rather than the boom’s tilt.