What happened
The flight was conducted under instrument flight rules, yet the aircraft lacked the necessary certification to operate safely within icing conditions. During the climb or cruise phase at 4,000 feet mean sea level, the outside air temperature remained above freezing, posing no immediate threat from ice accumulation. However, as the descent continued to 3,000 feet mean sea level, the aircraft entered a cloud layer where the outside air temperature dropped to exactly 32 degrees Fahrenheit. These conditions created a high risk for structural icing.
Despite the hazardous environment, the pilot elected to proceed with an instrument landing system approach and subsequent landing. The pilot maintained visual contact with the ground at approximately 450 feet above ground level. At this critical altitude, the aircraft encountered strong downdrafts accompanied by significant fluctuations in airspeed. The pilot later stated that he believed he had successfully aligned with the runway and did not consider executing a go-around maneuver.
As the aircraft neared the runway threshold, it ballooned upward due to the wind shear effects and approached a stall condition. In response, the pilot pushed the nose down to regain airspeed and control. This corrective action resulted in the nose wheel striking the ground with excessive force, causing the gear to collapse upon impact.
The investigation
Post-accident examination of the airframe revealed significant evidence of ice accumulation. At least half an inch thick ice was found on the leading edges of the wings and the empennage, extending from back to front and measuring one inch across. This physical evidence confirmed that the aircraft had flown into icing conditions for which it was not equipped.
Findings
The accident sequence was driven by a combination of environmental factors and pilot decision-making. The primary contributing factor was the operation of an aircraft not equipped to fly into icing conditions while in clouds with freezing temperatures. Additionally, the encounter with strong downdrafts and airspeed fluctuations during the final approach phase led to a loss of control margin. The pilot's decision to continue the approach without considering a go-around when visual contact was made at 450 feet further compounded the risk, leading to the hard landing and subsequent nose gear collapse.