What happened
On July 23, 2001, a Robinson R22 Beta II helicopter, registration I-JAHO, was conducting an IFR training flight near the Gargano promontory. The aircraft departed from the Aviosuperficie “Falcone” in Gaudiano di Lavello with two pilots on board. During the flight, the helicopter experienced continuous yawing motions that persisted even as the pilot increased power and climbed.
As the aircraft approached Vieste, the pilot attempted to turn toward the coast to return to base. During this maneuver, the helicopter began losing altitude. At approximately 1,500 feet, unable to regain height, the pilot initiated an emergency autorotative landing on a hilly area covered in Mediterranean scrub with a slope of roughly 30 degrees. During the descent, the tail rotor struck a bush, causing one blade to break and triggering a sudden rightward rotation. The aircraft impacted the ground, resulting in significant damage to the main rotor blades, tail rotor, and transmission, as well as deformation to the skid and tail boom.
The investigation
The ANSV investigation examined the environmental conditions, the aircraft's airworthiness, and the pilot's flight conduct. Investigators determined that the local topography of the Gargano promontory, combined with existing wind conditions, likely created localized turbulence and strong downdrafts. The pilot's decision to maneuver toward the coast placed the aircraft in a leeward position relative to the hills, where turbulence is typically more severe.
Furthermore, the investigation reviewed the pilot's adherence to the flight manual. Specifically, the manual's safety notice regarding strong winds and turbulence advises pilots to avoid flying on the leeward side of hills and to avoid abrupt control movements. The investigation found that the pilot's handling of the aircraft during the turbulence did not align with these recommended procedures.
Findings
- The primary cause of the accident was the loss of control due to atmospheric turbulence encountered near the coastline.
- The pilot's lack of experience in managing turbulence contributed to the event.
- Inadequate knowledge of the flight manual's specific procedures for turbulent conditions was a contributing human factor.
- The aircraft was found to be in an airworthy condition, and technical failure was excluded as a cause.