What happened
On September 2, 2000, at approximately 17:00 local time, a Bell B-2-05 (UH-1H) helicopter, operating under a firefighting mission, was involved in a collision with trees in the municipality of Mancor de la Vall, Mallorca. The aircraft, operated by BALEARES, had departed from Son Bonet airfield at 16:35 carrying a crew of two and eight firefighters to respond to a nearby wildfire.
While attempting to land the crew at the fire site, the main rotor blades struck tree branches. The pilot had been searching for a suitable landing zone in the rugged, mountainous terrain. After an initial unsuccessful attempt due to space constraints, the pilot approached a terrace. During a high hover to control the descent, the pilot maneuvered the aircraft forward to clear an olive tree. Believing the rotor area was clear of obstacles, the pilot initiated a vertical descent. During this maneuver, the blades struck the tree, causing audible impact noise. Despite the strike, the pilot was able to regain altitude and complete the landing without further incident.
The investigation
The investigation examined the environmental conditions and the pilot's maneuvers. At the time of the event, weather conditions were favorable, with visibility being good, temperatures at 22°C, and winds from 270° at 5 knots.
Examination of the aircraft revealed damage to both main rotor blades. Specifically, multiple impacts were found on the underside of both blades. On one blade, two impacts were severe enough to penetrate the skin and expose the internal honeycomb structure. The other blade sustained one similar impact. The investigation confirmed that the pilot's decision to move forward to avoid an obstacle placed the rotor disk in a position where it was no longer visible to the crew, leading to the collision.
Findings
- The primary cause of the accident was the impact of the main rotor blades with tree branches.
- The incident was driven by an attempt to land in an area that lacked sufficient clearance from obstacles.
- The pilot's maneuver to avoid a visible olive tree resulted in the rotor disk entering an unmonitored area of the terrain.