Ground Pattern Performance of the
Western Pilot Services Dromader

The Wildland Fire Chemical Systems (WFCS) program tests a variety of fixed- and rotary-wing tankers to determine the parameters for optimal ground pattern coverage over a wide range of fuel and fire conditions. The Western Pilot Services Dromader is an aircraft designed for use as an agricultural sprayer. It can be used for fire suppression by installing either the Transland or Melex gating systems.

The Transland and Melex gates differ in the size of the opening. The Melex gate opens 656 square inches (41 by 18 inches) and has an average flow of 450 gallons per second. The Transland gate opens 390 square inches (39 by 10 inches) and has an average flow of 80 gallons per second. Both the Transland and Melex gates are mechanically operated. The aircraft's tank holds 500 gallons, all of which is released at one time. Tests included airspeeds from 74 to 96 knots (85 to 110 mph) and drop heights from 40 to 120 feet from the bottom of the door to ground. The drops were made with three different materials: water, foam, and gum-thickened retardant.

The Missoula Technology and Development Center tested the Western Pilot Services Dromader (Figure 1) 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.

Figure 1–The Western Pilot Services Dromader.