What happened
The incident involved a Cessna 140 operating during the landing phase of flight. As the aircraft was established on short final approach, the student pilot permitted the airspeed to decrease below safe limits. Recognizing the deteriorating situation, the instructor pilot assumed control of the aircraft in an effort to execute a go-around or flare properly.
Despite the instructor's immediate intervention, the aircraft remained too slow to generate sufficient lift for recovery. The plane impacted the ground with significant force just short of the runway threshold, landing in rough terrain rather than on the paved surface. The impact forces were severe enough to cause structural failure of the landing gear system.
The investigation
Examination of the aircraft revealed that the left main gear collapsed upon impact. This mechanical failure was a direct result of the excessive vertical load generated by the hard landing. No other pre-impact mechanical anomalies were noted in the narrative provided.
Findings
The primary factor leading to the accident was the loss of airspeed control during the critical final approach segment. The inability to maintain adequate energy state prevented the crew from executing a safe touchdown or a successful missed approach maneuver.