AAIB investigation to Schempp-Hirth Duo Discus T, G-SAXT
‘Turbo’ propeller blade detached near Droxford, Hampshire, on 6 September 2015.
Summary:
The pilot of the glider deployed the self-sustaining engine in preparation for crossing a stretch of water but, after about five minutes running, there was a bang followed by severe vibration as the propeller shed one of its five blades. He also sensed a restriction in aileron movement, so decided to force-land in a field, which he carried out successfully without further incident or damage.
It was found that two segments of the propeller hub had failed and caused release of the blade, which had embedded itself in the left wing root. Subsequent examination found that the failures were due to metal fatigue cracking, a known problem with this model of propeller.
Download report: