Any source of heat, natural or human made, capable of igniting wildland fuels. Flaming or glowing fuel particles that can be carried naturally by wind, convection currents, or by gravity into unburned fuels.

Externally mounted rack for transporting supplies or cargo aboard a helicopter.

The process by which a helicopter fills a helibucket while hovering above the water source.

Burning technique in which lines of fire are started simultaneously from the apex of a ridge point, and progress downhill, maintaining position along the contour; used in hilly areas to ignite ridge points or ridge ends.

A subjective assessment of the health of individual plants in similar site and growing conditions; or a more specific measure based upon a specific facet of growth, such as seed stalk or tiller production per plant or per unit area.

Generally, wind speeds and wind directions at various levels in the atmosphere above the domain of surface weather observations.

An obstruction-free circle around the (helicopter) landing pad.

Person whose principal function is fire suppression.

An agent that extinguishes the flaming and glowing phases of combustion by direct application to the burning fuel.

Applies to radio frequencies primarily used for air operations.