Bird Strike Analysis on an Aircraft Aerofoil

Abstract

Bird strikes have long been a significant threat to aviation safety. The first bird strike dated back to September 7, 1905, recorded by the Wright brothers. The United States Air Force reported 13427 bird/wildlife strikes to aircraft worldwide between 1989 and 1993, and estimated the damage to civilian and military aircraft to cost hundreds of millions of dollars every year. Most bird strikes occurred when an aircraft was at a low altitude during the takeoff and landing phases of a flight. The most vulnerable components to bird strikes are aircraft engines, nose, and wings. To ensure flight safety, aviation regulations require a certain level of bird strike resistance for critical components. As specified in Part 25 of Federal Aviation Regulations, an airplane must be capable of successfully completing a flight during which likely a structural damage occurs as a result of impact with a 4 lb (1 lb = 0.4536 kg) bird (8 lb for an empennage structure) when the velocity of the airplane relative to the bird along the airplane’s flight path is equal to Vc (design cruise speed) at the sea level or 0.85Vc at 8000 ft (1 ft = 0.3048 m), whichever is more critical. Similar requirements have also been included in the China Civil Aviation Regulations (CCAR) and the certification specifications CS-25 (Large Airplanes) by the European Aviation Safety Agency. This calls for continuous efforts to design bird-strike-resistant aircraft components through a combination of tests and simulations.