Risk Analysis of High-speed Aircraft Departures Below 10,000 Feet

This paper abridges a Canadian study that examined bird-related safety risks to aircraft climbing to 10,000 feet MSL (mean sea level) at speeds in excess of 250 kias (knots indicated airspeed). The study employed a risk-based framework to examine ornithological information, bird strike data, aircraft-certification standards, aircraft climb performance and aircraft flight profiles. Foremost among its findings, the study determined that populations of high-risk bird species are increasing, that many of these species flock at the altitudes in question, and that aircraft exposure to risk will increase in part because of projected increases in aircraft movements. Examining the appropriateness of current and proposed mitigation, the study determined that current airframe and engine certification standards do not reduce risks associated with strikes by high-risk bird species. The study also found that any potential operating-cost savings that might be achieved through increased flight speeds would be more than offset by losses incurred through bird strikes. The study predicted that higher flight speeds would increase the total number of bird strike events involving high-risk species, the number of occurrences involving major damage, and the potential for catastrophic losses. Accordingly, the study concluded that aircraft should remain restricted to speeds of 250 knots or slower below 10,000 feet MSL