DESERT SEARCHES: THE EFFECTIVENESS OF HELICOPTERS Figure 5 Basic Creeping Line Search Pattern The solid line denotes the boundary of the search area. The dotted line denotes the flight of the helicopter. The distance between successive horizontal lines is the "track spacing". The vertical arrow denotes the extent that scanners search on either side of the flight path. NOTE: The actual number of legs flown will depend on the size of the search area together with the track spacing.