What happened
The pilot was operating a helicopter and initiated a maneuver to transition from forward flight into a stationary hover. As the pilot increased the collective pitch to gain altitude and stabilize the aircraft, the helicopter immediately rolled onto its right side.
The pilot reported that the aircraft was positioned directly into the sun. Additionally, intense glare was experienced due to sunlight reflecting off surrounding snow banks, creating a dazzling visual environment. The pilot did not report any mechanical difficulties with the helicopter prior to or during the incident.
Findings
The primary factor contributing to the event appears to be the loss of visual reference or orientation caused by environmental conditions. The combination of direct sunlight and reflected glare from snow likely impaired the pilot's ability to maintain proper attitude control during the critical phase of hover transition.