Le Ka 8 s'enfonce dans les arbres en virage de pente lent et bas

Un Ka 8 B, piloté trop lentement sur une pente à Veysonnaz lors du dernier solo d'un élève avant l'examen, s'est enfoncé dans les arbres ; pilote indemne, planeur fortement endommagé. Avec environ 12 heures de vol, il avait volé la même pente en biplace peu avant. Il s'est éloigné de parapentes vers l'ascendance plus faible de la forêt. Sur un passage rectiligne, une rafale a soulevé l'aile droite ; déjà trop lent, le planeur est devenu difficile à contrôler, et un virage bas a encore réduit la vitesse. L'évitement des parapentes n'a pas été une cause directe ; le planeur était trop lent en ligne droite, puis a viré trop bas et lentement.

1. Ridge soaring flight: After an earlier dual instructional ridge-soaring flight, the student pilot launched by aerotow from Sion for a solo ridge-soaring gain-of-height flight in the Ka-8b.
2. Avoiding paragliders: While soaring near Veysonnaz, the pilot observed several paragliders and moved away from their area toward the forested slope where the lift was weaker.
3. Low airspeed near slope: During straight flight on about the fifth pass parallel to the slope, the glider was already flying at too low an airspeed, reducing control margin close to terrain.
4. Gust upsets glider: A strong gust suddenly lifted the right wing during straight flight along the slope, abruptly upsetting the glider's attitude.
5. Ineffective control inputs: The pilot applied full right aileron, full forward stick, and full right rudder but the glider continued to sink and remained difficult to control.
6. Low, slow turn into slope: The pilot then reversed to left stick and turned toward the slope to execute a 180° turn, during which the airspeed decreased further before he attempted to pitch up to clear the treetops.
7. Crash - no injury: The very slow glider struck the tops of the trees, was abruptly stopped and then tipped forward to hang vertically between trees, heavily damaging the aircraft while the pilot remained uninjured.