Prevailing Cultural / Organizational Factors

Prior to the accident there were no explicit standards relative to the bird threat for airplanes or engines. Historically, birds had not shown themselves to be a particularly major threat. Prior to the accident there were no explicit standards relative to the bird threat for airplanes or engines. Historically, birds had not shown themselves to be a particularly major threat. Reciprocating engines require lower airflows than do turbine engines, which results in smaller air intakes, and associated naturally smaller capture areas than on turbine engines. Further, reciprocating engines, due to their lower overall airflow requirements are capable of withstanding larger variations in inlet airflows than are turbine engines, so may have been less susceptible to foreign object ingestion than a turbine engine. The overall effect was that bird ingestion did not seem to be a threat to an engine's ability to experience a bird ingestion event and continue to run.

With the inception of turbine powered airplanes, it was expected that the favorable operational history with reciprocating engine-powered airplanes would continue. The Electra accident and subsequent incidents and accidents would underscore the need for specific bird standards to be applicable to turbine engines and turbine engine-powered airplanes.

Photo of Reciprocating Engines
Frontal areas of large piston engines (above left), unlike the turbine powered L-188, were not as vulnerable to damage from bird strikes.

Left: Photo copyright Christian Waser - used with permission
Right: Photo copyright Wolodymir Nelowkin - used with permission

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