Discus B / Standard Cirrus mid-air on short final after no circuit position calls

A Discus B and a Standard Cirrus collided on short final at Hinton-in-the-Hedges after a club competition; the Discus B pilot was fatally injured and the Cirrus pilot seriously injured. Position calls in the circuit had been briefed; witnesses heard none from either pilot. Both joined the left-hand circuit at the same time from different positions, unaware of each other. On final the Standard Cirrus made a shallow right turn toward RWY 09, placing it on a conflicting path with the Discus B aligned for RWY 06; collision occurred at ~8 m AGL. AAIB cited the absence of position calls and the converging final paths.

1. Competition return: Both gliders were returning to Hinton-in-the-Hedges from a local inter-club cross-country competition. The Discus B (Intermediate class, 117 km task) crossed the finish ring at 14:39 UTC at ~1,900 ft AGL; the Standard Cirrus (Novice class, 81 km task) crossed at 14:45 UTC at ~1,000 ft AGL. The competition briefing required position reports on downwind, base, and final on Hinton Radio (119.455 MHz).
2. No position calls in circuit: AAIB-cited causal factor. Multiple witnesses on the frequency reported no position calls heard from either accident pilot. The Standard Cirrus pilot recalled a downwind call but not base or final. Both pilots came from Weston-on-the-Green, where position calls in the circuit were not routinely made — a witness described it as 'unusual' for either pilot to have made circuit calls at Weston. AAIB notes the operating culture likely shaped their perception of radio communication as supplementary rather than integral.
3. Both joined circuit unaware: Both gliders positioned northeast of the airfield for left-hand circuits at approximately the same time but from different positions and altitudes. Without position calls, situational awareness depended entirely on unalerted visual lookout. Neither pilot visually detected the other; AAIB cites the limitations of human visual and information-processing systems documented in prior see-and-avoid research.
4. Converging 30° final approach paths: On final approach, the Discus B was lined up with RWY 06 (grass) and the Standard Cirrus was slightly ahead and lower, on a shallower profile apparently aligned with RWY 06 (hard). The ~30° convergence angle created a challenging visual detection scenario, with possible cockpit-structure blind spots for either pilot.
5. Cirrus's late right turn toward 09: The Standard Cirrus then made a shallow right turn toward RWY 09 (grass) with airbrakes closed or partially closed. This placed it directly on a conflicting path with the Discus B. The reason for the late turn could not be confirmed; the pilot could not recall which runway he had intended. Possible motivations per AAIB: perceived insufficient height to reach RWY 06, or avoidance of overflying the village of Charlton.
6. Mid-air collision at ~25 ft AGL: The gliders collided 20-30 ft above the intersection of RWY 06 (hard) and the disused RWY 09 threshold. The Standard Cirrus's right wingtip struck the Discus B's canopy and then leading edge struck the cockpit coaming. The Discus B pitched up, rolled inverted, and struck the ground inverted — pilot fatally injured (head injury). The Standard Cirrus came to rest upright, entangled with the Discus B — pilot seriously injured. The low height precluded effective parachute use. Discus B destroyed; Standard Cirrus substantially damaged.