Natural features within the search area have the potential of reducing scanner effectiveness. For example white flowers, the light crown of cholla and saguaro cactus, reflections from puddles, and moving wildlife are among the many desert inhabitants that could, for an instant, distract the scanners from their objective. Although the distractions require brief examination by the scanner to confirm their insignificance, such brief inspections may disrupt the scanner's normal searching procedure, and the victim could easily be passed over during this period.

Contemporary search theory is that hasty, non-thorough search methods are among the most profitable tactics at the onset of the search mission. Air crews participating in this experiment believe that it is a sound procedure to initiate the air search at a high altitude and air speed in order to scan the entire area with close attention to natural attractions and obvious routes of travel. This enables the team to quickly find the easily detectable victim or clues. More thorough methods involving lower altitudes and air speeds can follow the hasty search, increasing coverage in high probability areas. Furthermore, the work of Wartes [1], where it is found that "nonthorough" searching with multiple passes produces a higher probability of success per hour spent in the search, will apply to the "creeping line" search used in this experiment. Therefore, it may be more advantageous to use a broader gridded creeping line and conduct as many multiple passes as possible if there is a choice.

These experiments were conducted using a specific type of military helicopter with a full search crew. Other types of aircraft (such as smaller helicopters and fixed wing aircraft) will probably have lower detection probabilities due to decreased crew size, fewer scanners, higher speed, and poorer visibility.

During the experiment it was found that the area immediately below and slightly to the side of the helicopter is an area of reduced detectability. In fact 8 out of the 22 victims not found stated that the helicopter flew directly overhead. (This reduced detectability is evidently consistent with what has also been observed in maritime search applications [2]). It is felt that the effect of this area of lower detectability could be reduced a great deal by conducting multiple passes which are perpendicular to the original path of the aircraft.

With the belief that the successful SAR manager should constantly strive to increase his/her understanding of the search resource's limitations and effectiveness, this initial survey of helicopter search effectiveness suggests that further research of this type should be conducted involving not only helicopters, but also other resources.