Background
The accident flight had encountered weather conducive to airframe ice formation during descent into Cleveland, approximately 40 minutes prior to the accident.
Event Details
During a 35-minute turnaround at Cleveland, the flight crew did not exit the airplane to conduct an exterior preflight inspection to verify that the wings were free of ice contamination. Snow was falling while the aircraft was on the ground. Immediately after takeoff, the airplane stalled and rolled into the ground.
Operational Context
The operator had no requirement for the crew to perform a preflight inspection for ice contamination. The crew had not received training regarding the effects of wing contamination on the airplane's performance.
Regulatory and Manufacturer Awareness
The Federal Aviation Administration (FAA) and the aircraft manufacturer had been aware for several years of the propensity of the DC-9 series 10 to experience loss of control caused by wing contamination. However, neither entity took positive action to include related information in the approved airplane flight manual.
Injuries
Both pilots were killed in the accident.
Probable Cause (Official Findings)
The failure of the flightcrew to detect and remove ice contamination on the airplane's wings, which was largely a result of a lack of appropriate response by the federal aviation administration, Douglas aircraft company, and ryan international airlines to the known critical effect that a minute amount of contamination has on the stall characteristics of the DC-9 series 10 airplane. The ice contamination led to wing stall and loss of control during the attempted takeoff.