What happened
On July 3, 2024, at Budaörs Airfield (LHBS), a Schleicher K-7 glider, registration HA-4047, was performing a training flight with an instructor and a student. During the landing phase on runway 27, the aircraft experienced a sudden increase in sink rate, resulting in a hard landing. The impact caused significant structural damage to the aircraft, including the deformation and breakage of the landing gear attachment points and the bending of a longitudinal metal member in the fuselage frame.
The investigation
The investigation examined the flight path using data from a mobile flight logging application, which revealed that the ground speed decreased significantly during the approach. The investigators also performed a material analysis of the damaged landing gear attachment, which confirmed that the damage was caused by high mechanical stress from the impact. The committee interviewed both the instructor and the student and reviewed meteorological data, which indicated wind gusts between 10 and 15 knots and potential turbulence near the landing zone.
Findings
The investigation established that the direct cause of the event was a decrease in situational awareness by the instructor due to limited experience, which resulted in a failure to correct errors made by the student pilot. Specifically, the student's approach speed was insufficient, and the instructor failed to intervene during critical flight phases.
Contributing factors included:
- The aircraft's takeoff mass exceeded its maximum allowable limit by approximately 10 kg.
- The use of the airbrake 1.7 seconds before touchdown increased drag and exacerbated the sink rate.
- A failure to properly execute a flare maneuver 0.7 seconds before touchdown.
- Environmental factors, including turbulence and wind gusts from nearby vegetation, which may have destabilized the approach.