August 1, 1973: The Boston skyline was visible in the distance as investigators stood by the opening in the seawall on runway 4R. The aircraft had hit the three-foot-high seawall at the end of the runway. The plane departed from Burlington, Vt., and was originally due in Boston at 9:41 a.m. but made an unscheduled stop in Manchester, N.H. to pick up passengers who had been stranded there when a Delta flight to New York was canceled because of fog.