Slingsby Swallow T45 hillside impact in severe sink — speed below ridge minimum

A Slingsby Swallow T45 struck the side of Bishop Hill near Portmoak Airfield (Kinross); the pilot was seriously injured. After a winch launch to 335 m AGL the glider approached the ridge at ~83 km/h — just below the 1.45 Vs (~85 km/h) recommended for ridge soaring. Below the summit the glider met turbulence and severe sink. An intended left turn away from the hill could not be completed; the glider struck the hillside and travelled through gorse. AAIB cited the approach speed below the ridge-soaring minimum, leaving insufficient energy to manoeuvre away in turbulent sinking air.

1. Ridge soaring flight at Bishop Hill: After a winch launch from Portmoak Airfield (EGPT) at 13:25 UTC to 335 m AGL (~440 m AMSL), the pilot headed directly to Bishop Hill (summit ~425 m AMSL), about 1 NM north. Reported wind 270° at 8-10 kt. Two other gliders and a paraglider were already flying near the ridge line.
2. Low recent currency: The pilot held 114 h total and 2 h on type, with 1 h in the last 90 days and 0 h in the last 28 days.
3. Speed below ridge-soaring minimum: Approaching the hill the pilot reported an airspeed of ~45 kt (1.4 Vs, where Vs was stated as 32 kt). The FFVP — referenced by BGA guidance on hill/ridge/mountain soaring — recommends a minimum of 1.45 Vs (~46 kt) to maintain enough excess energy to fly through areas of strong sink or windshear without stalling.
4. Severe sink below the summit: Flying parallel to the windward ridge line at a visually estimated ~245 m below the summit, the glider briefly climbed then encountered turbulence with the variometer indicating 'severe sink'.
5. Intended left turn away: The pilot stated an intention to make a left turn away from the hill. The pilot's next recollection is of the glider striking the hillside; the turn was not completed.
6. Hillside impact through gorse: The glider struck the side of Bishop Hill and travelled through gorse before coming to rest. Wings and cockpit substantially damaged; pilot seriously injured and airlifted to hospital. Glider control continuity verified intact post-accident. AAIB: lower than recommended airspeed left insufficient energy to manoeuvre safely away from the hill in turbulent sinking air.