Page:CAB Accident Report, Pennsylvania Central Airlines Flight 19.pdf/81

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flight control, but the testimony of eye witnesses as to the relative position of the airplane and the flash of lightning would lead to a conclusion that the lightning discharge occurred in front of the plane rather than to one side or in back.

According to Dr. McEachron's testimony, the greatest damage by lightning occurs at or near the earth terminal of a brief, high current value discharge. It is natural to consider the destructive force of such a discharge at or near its cloud terminal. There is some reason to believe that the airplane in this case must have been just about to enter the cloud and its rainstorm at the exact moment of the flash of lightning. It is useless to speculate as to whether or not this airplane may have been in the cloud terminal of the lightning discharge or what may have been the effect of its being there since Dr. McEachron pointed out the limited knowledge on the subject and the obvious difficulty of research.

Upon the evidence of record, we cannot conclude that the airplane was struck by the usual type of lightning which produces a thermal effect; that the airplane or its crew were injured by any electrical effects of lightning other than acoustical shock; or that lightning itself produced any turbulence which changed the flight attitude of the plane. We, therefore, conclude that none of these phenomena of lightning were related to any cause of the accident.

We do think it possible that lightning may have temporarily blinded the pilots or that the pressure wave resulting from the lightning may have subjected the pilots to acoustical shock or concussion; may have smashed the cockpit windows, or may have caused other damage to the structure and controls of the airplane through mechanical effect.