Narrative:TWA Boeing 707 N748TW and Eastern Constellation N6218C approached Carmel VORTAC at FL110 resp. FL100. Due to an optical illusion caused by the up-slope effect of cloud tops, the Eastern 1st officer thought they were on collision course with the TWA jet. He pulled up the Constellation. The reaction of the TWA crew was to roll to the right, followed by a left roll down. Both aircraft collided. The Boeing made a safe landing.
PROBABLE CAUSE: "Misjudgement of altitude separation by the crew of EA853 because of an optical illusion created by the up-slope effect of cloud tops resulting in an evasive manoeuvre by the EA853 crew and a reactionary evasive manoeuvre by the TW42 crew."
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Map
This map shows the airport of departure and the intended destination of the flight. The line between the airports does
not display the exact flight path.
Distance from San Francisco International Airport, CA to New York-John F. Kennedy International Airport, NY as the crow flies is 4124 km (2577 miles).