Analysis of bird strikes at a tropical airport

Bird-aircraft collisions (bird strikes) are a major problem worldwide because they threaten passenger safety and result in costly repairs and lost revenue for the commercial air carrier. From 1990 to 1994, we conducted runway sweeps at Lihue Airport on Kauai, Hawaii searching for avian remains from bird-aircraft collisions. Three species of granivorous birds, 2 owl species, and the Pacific golden-plover (Pluvialis fulva) composed >80% of the bird strikes. Ninety-one percent of the strikes involved solitary birds; 9% involved >1 bird. Bird strikes were positively correlated with mean monthly rainfall, perhaps due to increased seed production along runways during the rainy months, resulting in increased bird use in hazardous areas. Bird strike rates were also higher when winds were from a southwesterly direction and lower when cloud cover was 100%. Larger, faster commercial air carriers exhibited higher strike rates than military or general aviation types, with engine ingestions being most common, followed by strikes on the windshield and nose. Ingestions resulted in losses >$1.5 million in damage. Damage was caused by species ranging in mass from 13-1,300 g. More bird strikes occurred during landings than takeoffs with strikes unevenly distributed along the runway. During the landing phase, more bird strikes than expected occurred at the point of touchdown, whereas most strikes occurred in the mid-portion of the runway during takeoffs.