Preparations for the helicopter operations are discussed ranging from acquiring the aircraft, facilities, and support equipment, to insurance and pilot training. The patrol operations, special high crime mission areas, and the problems which arose in fully implementing the helicopter program are described. Excerpts from four observer reports show the dramatic impact of the helicopter on the apprehension of suspects. The effectiveness of these operations is evaluated in terms of apprehension statistics, analysis of the circumstances of arrest (response time and arrest), comparison of arrest data, and costs. The evaluation is made on calls which come in and which result in the dispatch of helicopters and calls which come in when no helicopters are available. Findings indicate that there was a 30 percent increase in arrests due to the helicopter, but that the helicopter as decisive effect depended largely on its being the first unit on the scene; that the helicopter's presence did not result in the arrest of additional offenders; and that one arrest situation was attributable to the helicopter for every 45 hours of patrol time (at a cost of $106 per flying hour). A larger evaluation of the effect of helicopters upon crime prevention is detailed, and results do not show significant impact. The odds are said to be seven to three in favor of the helicopter affecting the crime incidence in those areas it patrolled. Nine tables present the data gathered for the report. Two appendixes describe procedures developed for data gathering and the helicopter summary system.