Eurocopter AS332L1 N950SG accident near Azusa, California

Probable cause

The pilot's failure to maintain clearance from a tree after encountering brownout conditions and a loss of visual reference during the approach to land.

NTSB analysis

The pilot of the helicopter stated that, while maneuvering around the area looking for a suitable landing site, a dirt turnout alongside a road was selected. A tree was noted on the edge of the turnout. An approach was initiated to the site and expected brownout was encountered. About 5 ft above ground, the pilot heard the crewmember in the back of the helicopter call out “hold.” The pilot arrested the descent and came to a hover. Within seconds the asphalt roadway reference was obscured by the brownout and he lost visual reference. He announced, “lost visual” and started to climb, which was his last recollection before regaining consciousness.

The crewmember in the back of the helicopter reported that the helicopter approached the landing zone angled, to the south toward a tree. About 7 to 10 ft above the ground, he noticed that the helicopter was drifting forward, and he called out twice, “You are drifting forward, hold.” The helicopter continued to drift and subsequently, struck a tree and rolled onto its left side. The helicopter sustained substantial damage to the fuselage and main rotor system.

The pilot reported there were no mechanical malfunctions or failures with the helicopter that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for WPR22LA125 for the full record.