Portal:Civil Aeronautics Board

“ From technical data relating to airspeed and propeller blade angles it was shown that with the 52-degree angle there is no throttle position at which true airspeed could be less than 295 knots. Because this airspeed is excessive it is entirely logical to assume the throttle would have been closed to slow the aircraft. With the throttle closed a 52-degree blade angle reflects a true airspeed of 335 knots, which is 15 percent in excess of the Viscount never-exceed speed or about 5 percent in excess of D, the maximum speed demonstrated in certification. ”

“ The recommended rough air penetration speed for the Viscount is about 170 knots, the last airspeed reported by Flight 75. At or near this speed the aircraft strength is sufficient that extreme maneuver and/or gust loading will stall the aircraft rather than cause a structural failure.
Autopsies were performed on all of the crash victims according to provisions of the law of the State of Maryland. At the public hearing the Chief Medical Examiner testified relative to the findings in order that the Board could avail itself of every facet of information relevant to the accident. ”

“ Furthermore, the breakup sequence and the nature of the mass of fractures are entirely consistent with this as the initial occurrence.
Following separation of the right and left stabilizers the aircraft pitched down violently so that all four nacelles broke upward from combined inertia and gyroscopic loads. Immediately thereafter both wings were subjected to extreme downloads under which the right separated and the structural integrity of the left wing was destroyed. With the nacelles, right wing, and stabilizers gone, drag induced by the left wing yawed the fuselage violently to the left. ”

“ The majority of the ante-mortem injuries were described as scalp injuries of the type and degree which suggested heavy bumps on the head by contacting overhead structure. Others were seat belt injuries and two or three suggested forces applied downward on the body forcing it into the passenger seat. The findings showed that some passengers were exposed to an intense flash fire which contained droplets of flaming liquid. At least 10 passengers revealed an elevated level of carbon monoxide; the highest was about 10 percent, not normally a disabling amount. ”

“ It is considered possible under a similar occurrence that Captain Paddack attempted to maneuver out of such a situation and placed the aircraft in a turning configuration in which the aircraft could more easily be placed in an unusual attitude and in which control techniques would be more critical. Under any penetration are important factors. In its considerations the Board was also unable to rule out with complete definitiveness the possibility of a cockpit distraction or instrument failure at a critical moment. ”

“ Executing the clearance, Flight 75 made numerous radio communications in the New York area and proceeded uneventfully to its assigned cruising altitude, 14,000 feet, and onto the assigned airway, Victor 3. ”

“ FLight 75 taxied away from the terminal at 1520, 20 minutes lat. The last-minute delay occurred when Captain Paddack found an error in the aircraft gross weight computation and questioned the weight for the existing runway restriction. At 1455 the flight radioed for runway temperature. The senior operations agent came aboard and he and the captain rechecked the computations to make sure the weight was correct and below maximum allowable for the runway length, the existing surface wind, and temperature. ”