Incident Summary
An aerial application helicopter operating with a full fuel load of 55 gallons and a full spray load of 50 gallons took off using the entire runway length. After becoming airborne, the helicopter climbed and leveled off at 500 feet above ground level (AGL). According to witnesses, the helicopter required the entire runway to achieve lift-off.
Pilot Actions
Shortly after leveling off at 500 feet AGL, the pilot reported hearing a loud bang and feeling vibrations. In response, the pilot initiated an autorotation to manage the descent. The pilot stated that he began to flare the helicopter at an altitude of 50 feet but was unable to sufficiently reduce the rate of descent. Consequently, the helicopter executed a hard landing in a residential area.
Post-Landing Examination
Following the landing, an investigation of the helicopter's flight controls revealed no malfunctions. Additionally, a test run of the engine was performed and no problems were identified. The source does not specify any findings that would explain the loud bang or vibrations.