The object was to develop a simple, operational model for predicting air-to-ground visual detection/identification of tactical targets. The model, based on data from the literature, was limited to conditions of daylight and clear visibility. A preliminary model was developed using data from a field study (J.A. Whittenburg, J.P. Robinson and J.M. Hesson. Aerial observer criterion field test manual. Arlington, Va., Human Sciences Research, Inc., Sept. 1959. HSR-RR-59/4-CE) of air-to-ground detection/identification of tactical targets. Variables to be included in the model were selected from a list of variables found to be important in previous studies. The model includes estimates of eight input variables--target size, target shape, target/ground contrast, clutter, terrain type, aircraft altitude, aircraft speed, and range--which were grouped into three composite variables (target apparent size, target distinctiveness, and effective exposure time). A numerical summary of relevant studies on target detection/identification and a description of model calculations are presented as appendices.

The U.S. Army Human Engineering Laboratory conducted a series of flight tests in 1972 (HELHAT I) and 1973 (HELHAT II) in which the low-level target acquisition performances of combat-trained OH-58 and AH-1 helicopter crewmen were measured. The stationary targets used were both ordnance and high-visibility box-type targets. This study contains all of the data gathered during these tests and also reports on the 25 performance variables measured for each of the 851 recorded target acquisitions. These variables were used to form the linear equations which were analyzed by the use of a step-wise multiple-regression technique in order to identify the variables contributing to stationary target acquisition performance. There were 831 acquisitions recorded during the low-level route reconnaissance flights flown at above the ground levels of 80 to approximately 400 feet and 20 acquisitions recorded during the six nap-of-the-earth 's' search reconnaissance flights flown at above the ground levels of 1 to approximately 40 feet.

Information on visual target detection is widely scattered in the literature. The thesis presents a review and a categorization of current literature and provides a general discussion of representative models in the field of visual target detection. A literature research matrix is presented to aid the researcher in locating existing models which meet his requirements. (Author).