What happened
On June 10, 2011, a Bell 206 B helicopter, registration F-GLUP, was conducting an ab initio flight training session at the Valence Chabeuil aerodrome. The flight crew included an instructor pilot, a student pilot in command, and a second student passenger. During the fourth circuit of the session, while on the downwind leg, the instructor simulated a hydraulic failure to test the student's proficiency.
Following established procedures for such an emergency, the student pilot performed a side-slip landing on the unpaved runway. While the initial contact of the skids with the ground was successful, the aircraft began to nose down. The front of the right skid sank into the soft terrain, causing the airframe to pivot forward and to the right. This movement caused the main rotor to strike the ground, subsequently causing the helicopter to tip onto its left side. The aircraft was destroyed, and the instructor sustained slight injuries.
The investigation
The investigation focused on the surface conditions of the landing area and the pre-flight preparations. Investigators examined the meteorological conditions, which were noted as CAVOK with a light wind from 020° at 6 knots. The investigation also reviewed the flight history of the crew and the previous landings performed during the session. It was noted that previous side-slip landings had been conducted nearby without incident.
Findings
- The landing area consisted of soft, unpaved ground.
- The instructor had performed a visual reconnaissance of the airfield prior to the session but failed to detect the soft nature of the landing zone.
- The instability of the ground caused the right skid to penetrate the surface, leading to the loss of control and the subsequent rotor strike.