An Investigation Of Some Parameters Related To Midair Collisions Of Aircraft PDF Download

"A study has been made to develop a basic means, in the form of graphs and charts, for permitting a better understanding of cockpit visual problems and aircraft conspicuity problems as they are related to mid-air collisions. Formulas are derived and visual-angle and distance charts are presented for certain combinations of straight-and-level, climbing, descending, and turning flight conditions. Using only aircraft headings and speeds, the visual angles and distances between aircraft at assumed instances of time prior to collision may be determined from these charts. It is also possible to obtain critical collision-course headings by entering the charts with the effective cockpit cut-off vision angles and speeds. Tables are presented showing actual airplane attitudes during flight. Actual flight paths recorded in the vicinity of airports are presented. Some performance parameters used in the design of the visual-angle charts contained in this report were established from these flight-path data. From the graphs contained in this report, it is evident that: 1. No apparent motion from pilots' viewpoints exists between two aircraft which are flying straight and level on collision courses at constant speeds. 2. The most severe mid-air collision hazard from a visual-angle standpoint exists between aircraft that are flying at small differences of heading and speed. During this condition, even when the closing rates are small and much time is available for evasive maneuver, the visual-angle restrictions of present-day transport aircraft do not permit the pilots to observe each other. 3. Mid-air collisions cannot be avoided by use of the windshield area alone, since extreme visual angles may be required during many collision conditions. However, certain minimum visual angles in aircraft-cockpit design will tend to decrease the probability of mid-air collisions."--Summary.