Recent data from the airlines lightning strike reporting project

Abstract

In 1971, General Electric Company and five United States commercial airlines initiated a project to obtain data on lightning strikes to transport-category aircraft. The purpose of the project was to obtain information on the conditions under which aircraft are most likely to receive lightning strikes in flight, and document the effects of these strikes on the aircraft. For this purpose, the airlines were provided with questionnaire-type reporting forms for use by pilots and maintenance personnel in documenting lightning strike events and effects on the aircraft. The motivation for the project stemmed from a need to obtain a better understanding of the conditions under which aircraft are struck, the places on the aircraft where strikes are most likely, and the effect of these strikes on the airframe as well as onboard electrical and avionic systems. Initial results from the project were published by General Electric in 1974. At that time, a total of 214 strike reports had been received. The data were found useful by lightning protection designers for new aircraft. For example, the strike reports helped clarify the locations of lightning strike zones on transport-cat egory aircraft, and alerted designers to potential lightninginduced voltage problems. Strike reports continued to be received by General Electric, but no further data summaries were published; therefore, in 1977, the project was taken over by Lightning Technologies Inc. By early 1984, nearly 800 lightning strike reports had been accumulated and Lightning Technologies Inc. invited the Federal Aviation Administration Technical Center to participate in the project by computerizing each of the strike reports and processing the data. With the data in computer memory, it would be possible to provide correlation among various reported conditions and effects. This paper presents a summary of the strike data obtained through January 1984.