What happened
On August 24, 2014, a Scheibe SF-28 A glider, registration F-CAQS, was performing a solo flight at Agen Aerodrome. Earlier that afternoon, the pilot had completed a training session with an instructor, practicing engine-off thermalling maneuvers at 2,000 feet. Following the instructor's authorization, the pilot proceeded to conduct the same flight profile solo.
During the landing approach on runway 29, the pilot maintained an engine-off configuration with a speed of 90 km/h and deployed the airbrakes to three-quarters. The pilot intended to touchdown near taxiway E, approximately 900 meters from the runway threshold. While attempting the flare at an altitude of roughly 2 meters, the aircraft touched the runway and subsequently bounced. In an attempt to control the flight path, the pilot retracted the airbrakes, which led to a second, more violent bounce. During this second impact, the main landing gear forced itself into the fuselage, causing the left rocker arm to break and the left wingtip to strike the runway. The aircraft came to a stop on the runway centerline.
The investigation
The investigation focused on the pilot's approach parameters and the aircraft's mechanical response during the landing sequence. Investigators reviewed the pilot's experience, noting that the 61-year-old pilot had 42 total flight hours, with 38 of those conducted under instruction on this specific type. Meteorological data indicated favorable conditions, with visibility exceeding 10 km and light, variable winds of 3 knots.
Technical analysis compared the pilot's actions against the aircraft's flight manual, which recommends an approach speed of 85 km/h and specifies that at a touchdown speed of 65 km/h, the tailwheel should make contact first. The investigation examined the sequence of airbrake deployment and the pilot's management of the aircraft's pitch during the flare.
Findings
- The aircraft approached the runway at a speed of 90 km/h, which exceeded the recommended approach speed of 85 km/h.
- The pilot failed to properly manage the aircraft's pitch during the flare.
- Inadequate use of the airbrakes during the landing phase was the primary factor leading to the unstable approach and subsequent bounces.