Bird strike

Understanding Bird Strikes: A Critical Issue in Aviation

Imagine an aircraft soaring through the skies, only to suddenly encounter a small but powerful adversary—birds. These collisions, known as bird strikes, are more common than you might think.

The Scale of the Problem

Over 13,000 bird strikes occur annually in the United States alone, with most being fatal to the birds involved. While many strikes result in minor damage, jet engine ingestion can lead to catastrophic failure due to the high-speed impacts and design of engines.

The Impact on Aircraft

High-speed impacts can cause significant damage, but 80% of bird strikes go unreported. Flocks of birds pose a significant threat during take-off and landing, as they can lead to multiple strikes that can be fatal if the aircraft cannot recover in time.

The Most Common Culprits

Which birds are most likely to cause these collisions? Large geese, gulls, Canada geese, snow geese, turkey vultures, and white pelicans top the list. The majority of bird strikes occur during spring and fall migrations.

Engine Design for Safety

Aircraft manufacturers design engines that can withstand a single bird strike but are disabled by multiple strikes. For instance, modern jet aircraft structures must be able to continue safe flight even if hit by one 8-pound bird. The FAA’s regulations mandate that birds must not cause damage anywhere on the empennage of an aircraft.

Countermeasures and Mitigation Strategies

To reduce the impact of bird strikes, various countermeasures are employed. These include designing vehicles to be more bird-resistant, moving birds out of the way, or moving animals away from aircraft.

Vehicle Design Features

Aircraft engines can shut down after ingesting a 4-pound bird, and modern jet aircraft structures are designed for continued safe flight even if hit by one such bird. The FAA’s regulations require that birds must not cause damage anywhere on the empennage of an aircraft.

Wildlife Management at Airports

Wildlife management strategies can be grouped into non-lethal and lethal methods, integrated for the most effective strategy. Non-lethal methods include habitat manipulation, exclusion, visual, auditory, tactile, or chemical repellents, and relocation.

Habitat Manipulation

Turfgrass should be managed to reduce wildlife attraction, with Augustine grass being a preferred species at heights of 7-14 inches through regular mowing and fertilization. Fences made of chain link or woven wire can exclude deer and other mammals, while cattle guards can deter them up to 98% of the time.

Technological Advancements

Bird strike testing involves limited testing with computer simulation and physical experiments. EASA proposed that engines should be capable of sustaining a bird strike in descent. New regulations may apply to Boeing NMA engines, while avian radar is used to track birds in real-time, providing safety management systems at airports.

Avian Radar Systems

The US Air Force uses near-real-time data to predict bird hazard conditions for military routes and areas. The Avian Hazard Advisory System (AHAS) reduces strike percentages associated with low-level flight operations from 25% to 12%. Avian radar is used by the FAA and DoD for civil and military applications, with systems like DeTect’s production model bird radar system widely used.

Real-World Examples

The impact of bird strikes can be devastating. For instance, in 1960, Eastern Air Lines Flight 375 crashed into Boston Harbor shortly after takeoff, killing 62 people. Minimum bird ingestion standards for jet engines were subsequently developed by the FAA.

Notable Incidents

A Dassault Falcon 20 crashed in 1995 after sucking lapwings into an engine, causing an engine failure and fire, killing all 10 on board. A US Air Force Boeing E-3 Sentry AWACS aircraft crashed in 1995 after ingesting Canada geese during takeoff, killing all 24 crew members.

Conclusion

Bird strikes are a critical issue that affects aviation safety and costs the industry millions annually. By understanding the problem, implementing effective countermeasures, and leveraging technology, we can mitigate these risks and ensure safer skies for everyone.