Positive bias in bird strikes to engines on left side of aircraft

Previous studies have indicated more birds collide with communication towers equipped with red warning lights than with towers equipped with lights of shorter wavelengths. We used the U.S. Federal Aviation Administration’s National Wildlife Strike Database to determine if a similar relationship exists for turbine-powered jet aircraft with 2 underwingor fuselage-mounted engines and bird strikes. We compared bird strikes reported to engine #1 (left side = red lighting) or to engine #2 (right side = green lighting) using chi-square tests (α = 0.05). For both underwingand fuselage-mounted engines, more (P ≤ 0.04) strikes were reported for engine #1 compared to engine #2 during Day, Night, and Dawn/Dusk fl ights. These fi ndings suggest that modifying red navigation lights to include shorter wavelengths and the use of supplemental lights specifi cally designed for avian vision could enhance detection and reduce bird strikes.