What aircraft was involved and where did it happen?

The accident on 2002-07-26 involved a aircraft, at FR.

What was the probable cause of the accident?

The primary cause of the mid-air collision was a loss of situational awareness due to high pilot workload while navigating difficult thermal conditions, compounded by the failure of the crews to visually detect each other in time to avoid the converging flight paths.

Mid-air collision between two gliders near Limoges

A mid-air collision between two Centrair gliders resulted in the destruction of one aircraft and injuries to two people during a flight training session.

What happened

On Friday, July 26, 2002, at 14:45, two gliders, a Centrair C 201B (registration F-CBLR) and a Centrair C101 A (registration F-CHED), were operating near Verneuil-sur-Vienne, France. The F-CBLR was conducting an introductory flight for a young student, while the F-CHED was performing a local flight.

Both aircraft had departed from Limoges. While searching for thermals at approximately 600 meters, the pilot of the F-CHED observed the F-CBLR release from its tow. A few minutes later, as the F-CHED was executing a shallow left turn, the pilot of the F-CBLR felt a sudden impact against the canopy, which subsequently shattered. The pilot of the F-CBLR then returned to the Limoges aerodrome.

During the flight, the instructor in the F-CBLR had instructed the student to assist with external lookout duties. To facilitate better visibility, the instructor had loosened his harness. While turning right, the instructor spotted the F-CBLR on a converging path to the left. In an attempt to avoid the collision, the instructor performed a violent maneuver to the right and into a descent. This resulted in a collision where the tail boom of the F-CBLR struck the canopy and upper instrument panel of the F-CHED.

The impact caused the tail boom of the F-CBLR to separate from the forward section of the aircraft, leaving it attached only by control cables and rendering the glider uncontrollable. The instructor, facing a steep dive, attempted to evacuate the cockpit and deploy his parachute. The student remained in the aircraft, which struck the ground seconds later.

The investigation

The investigation focused on the sequence of maneuvers and the physical damage to both aircraft. Examination of the wreckage revealed that the tail boom of the F-CAHB had struck the canopy and dashboard of the F-CHED before separating. The investigation also reviewed the meteorological conditions and the workload of the crew members during the flight.

Findings

The collision was caused by a failure of vigilance resulting from a high workload caused by unfavorable aerological conditions, specifically weak and difficult-to-center thermals.
There was a lack of visual detection of the F-CBLR by the crew of the F-CHED (Pégase).
There was a delayed detection of the F-CHED (Marianne) by the crew of the F-CBLR.
The impact resulted in two injuries (the pilot and passenger of the F-CBLR) and the total destruction of the F-CBLR aircraft, while the F-CHED sustained delaminated wings and damage to the canopy and dashboard.