Pilatus B4-PC 11AF entra en pérdida durante intento de aterrizaje en el aeródromo de Fricktal Schupfart
El 16 de agosto de 1973, un Pilatus B4-PC 11AF experimentó una pérdida de sustentación mientras intentaba aterrizar en el aeródromo de Fricktal Schupfart en Suiza. El piloto, que realizaba un vuelo de entrenamiento local, soltó el remolque a aproximadamente 50-70 metros de altitud después de darse cuenta de que el planeador estaba más alto que el avión remolcador. Durante el enfoque de aterrizaje subsiguiente, el planeador voló demasiado alto y el piloto intentó un giro para volver a acercarse a la pista. El planeador entró en pérdida durante este giro a baja altitud y golpeó el suelo con su ala izquierda. El piloto resultó ileso, pero el planeador sufrió daños significativos.
- Aerotow initial climb: The glider HB-1119 departed Fricktal-Schupfart on aerotow from runway 26 for a local training flight and climbed normally to about 50–70 m above the field.
- Excess tow height: At approximately 50–70 m altitude the pilot found himself flying significantly higher than the towplane and lost proper tow position control.
- Early tow release: Because he was too high above the tug, the pilot released from tow at low altitude and turned left to return for an opposite-direction landing on runway 08.
- High, no airbrakes: On the return approach the pilot overflew the airfield at about 5–8 m without deploying airbrakes, resulting in an approach that was too high.
- Low-altitude re-approach: After overflying the runway, the pilot pulled up slightly at the end of runway 08, offset slightly right, and initiated a low-altitude left turn to set up a new landing approach.
- Stall in turn: During this low-altitude reversal turn the bank angle increased, the glider’s speed dropped below minimum, and it stalled and slipped inward, striking the ground with the left wing.
- Crash - no injury: The glider impacted with its left wing while the fuselage and right wing lodged in a tree, causing serious aircraft damage but no injury to the pilot.