Cantilever in an aerial device is defined as:

• A. The operation of an aerial device with the tip or platform resting on a support.
• B. The operation of an aerial device with the tip or platform supported by a nearby structure.
• C. The operation of an aerial device with the tip or platform unsupported in the air and not resting on an object.
• D. The operation of placing the device on a vehicle.

Answer: (C)

Cantilever in an aerial device means the tip or platform is unsupported in the air, not resting on any object. The end of the boom is extended out without contact to a structure or surface, so all support comes from the boom and base through the device’s hydraulics and stabilizers. This is distinct from situations where the tip is resting on a structure, supported by a nearby object, or when the device is placed on a vehicle. Operating in cantilever affects stability and load calculations because the end is free, increasing the moment at the base.