Investigation
The CAB investigated the accident and concluded that the aircraft had been overloaded by 2,000 lbs above its maximum certificated gross takeoff weight of 47,100 lbs, and that there was a partial power loss in the left engine prior to the crash.
Prior to takeoff the weather at the airport steadily deteriorated; at 7 pm the visibility was 3/4 mile, at 8:37 the visibility was down to 1/16 mile, and by the time of the accident the visibility was zero. The CAB accident report states that stemming from the crash, the FAA published a notice in the Airman's Guide that prohibited takeoff for commercial aircraft when the visibility is below 1/4 mile, or the runway visual range is below 2000 ft.
The CAB issued the following Probable Cause statement in its final report:
The accident was due to loss of control during a premature lift-off. Contributing factors were the overweight aircraft, weather conditions, and partial loss of power in the left engine.
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