Abstract: An air field space heater for a fog dispersal system of the type having a plurality of heaters for generating heated air along an aircraft runway. The heater generates heated air and directs it in the form of air jets with properly controlled magnitude of momentum at various angles of inclination relative to the plane of the runway, the angle of inclination being adjustable for dispersing fog under a variety of wind conditions. One form of the heater includes two warm air projectors coupled to two combustors. A single source of thrust power operates two propellers, one for each combustor. The air from the propellers, warmed by the combustors, flows into a pair of elbow conduits which are pivotable to pivot the projectors about a generally horizontal axis for adjustment of the angle of inclination of the projected air jets. The elbow conduits include fixed, low-loss turning vanes, and provide an efficient system for projecting the two air jets at various angles and with minimum drag.