Ground Pattern Performance of the
SEI Industries Bambi 324- Gallon Helibucket

The Wildland Fire Chemicals Systems (WFCS) program tests a variety of fixed- and rotarywing tankers to determine the parameters for optimal coverage over a wide range of fuel and fire conditions. The Bambi 324-gallon helibucket is one of a family of helibuckets designed for use with a wide range of helicopters.

The Missoula Technology and Development Center tested the Bambi 324-gallon helibucket with a series of drops over an array of plastic bowls much like Cool Whip containers. The quantity of material in each bowl was measured and the data were used to determine the drop pattern.

The helibucket is constructed of a heavy coated fabric mounted to a collapsible frame (Figure 1). The dump valve is electrically actuated from the helicopter using 28 volts dc aircraft power. The volume of a given drop can be controlled by the rate at which the helibucket is lifted from the water (a faster lift produces more volume) or by adjusting a cinch strap inside the helibucket. During the MTDC tests, the rate that the helibucket was lifted from the retardant was not controlled, producing variations in the volume dropped. The drops in these tests were made with the cinch strap at its maximum opening (maximum volume of 324 gallons).

Figure 1—Cutaway view of the Bambi helibucket.