Helicopter Night Low-Level Navigation: Study 1--Checkpoint Identification

This paper reports the results of the first in a series of studies of helicopter pilots' capabilities of navigating at night at low flight levels using unaided vision. This study tested the pilot-navigator's ability to identify pre-designated checkpoints at 100 feet, 200 feet, and 350 feet AGL over six separate routes. Pre-exposure to the route was controlled by flying the pilots over three of the routes during day-light hours. Results were interpreted on the basis of their influence in developing programs of instruction (POIs). On this basis it was concluded that prominent natural terrain features, rather than man-made features, should be used and that for checkpoint identification, no advantage accrues from altitudes greater than 200 feet AGL. The importance of adequate weather information and thorough pre-flight map preparation are also discussed.