Page:CAB Accident Report, Capital Airlines Flight 75.pdf/3

- 3 - speed. At the time of disintegration it was a clear area between clouds and near large thunderstorm buildups.

Of those who say the aircraft just before and during the breakup one was attracted by a loud engine or propeller noise, another said the sound was surging. Several saw a fire just before the breakup. Two placed it near the right wing root, another on top of the cabin, and another just in front of the tail. Most, however, said the only fire was a large flash explosive fire that occurred simultaneously with the inflight disintegration.

At least three eyewitnesses said the aircraft was struck by lightning and then it exploded; majority held that no lightning was involved.

Observers were most consistent that the right wing separated first, and instantly thereafter the remaining aircraft structure broke into three major sections. All agreed that most of the pieces fell to the ground in flames.

From those witnesses who could relate the accident to a specific time reference it was reliably determined that it occurred very close to 1613.

Since most who saw the aircraft break up estimated it was between 3,000 and 7,000 feet when it disintegrated instead of 14,000 feet, the assigned and last reported altitude, a flight test was made to determine the approximate altitude. A Capital Viscount was flown several times along the probable flight course of N 7463, at different altitudes from 3,000 to 14,000 feet while 11 eye-wittnesses watched from their original positions. Each designated the pass on which the altitude of the test plane was closest to that of N 7463 when it disintegrated. The result averaged 5,500 feet.

The main wreckage was located about 2 miles northeast of Martin Airport near Chase, Maryland. The area is 49 nautical miles from the Westchester omni on a magnetic heading of 236 degrees. The heaviest portions of structure were found concentrated in a localized area showing an instantaneous breakup of most of the aircraft, although many lighter and smaller pieces were drifted by northwest winds and deposited along a southeast path about 2-1/2 miles long. Some of this latter structure fell into swamp and heavily wooded areas and some into shallow inlets of Chesapeake Bay. AN exhaustive search, greatly assisted by several civil and military organizations, resulted in recovery of about 90 percent of the aircraft structure which was then moved to a hangar, laid out, and given meticulous examination.

The empennage structure was localized about one mile southeast of the main wreckage concentration. Examination of this structure showed both the left and right horizontal stabilizers failed downward along a chordwise line near the NO. 2 elevator hinge. The stub end of the left stabilizer was torn from the fuselage by forces predominantly rearward and downward. The remaining portion of the right stabilizer remained attached to the fuselage; however, the lower surface was wrinkled in the area adjacent to the fuselage. The upper surface was wrinkled at the root just forward of the spar and the wrinkle continued into the aft fuselage. Both elevators were torn off in sections by forces causing failures at the hinge points. The vertical fin was torn off by forces predominantly to the left. It separated, tearing with it part of the fuselage attachment frame at station 870.