Brantly B-2B accident near Weaverville, California, May 27, 2011

The NTSB's narrative final · quoted from the NTSB record

The student pilot’s solo flight endorsement prohibited flight in gusty wind conditions such as those existing at the time of departure along his route of flight and at his planned destination. Additionally, his route of flight would have been over mountainous terrain, which would have further exacerbated the conditions and resulted in updrafts, downdrafts, and turbulence at his flight altitude. A witness, who was located close to the accident site, reported unusually strong wind for the area at the time of the accident. The pilot did not request a weather briefing prior to the flight. The wreckage distribution was consistent with a level impact with trees in the direction of flight. No indications of an in-flight breakup, bird strike, or fire were present, and damage to the main rotor system was consistent with it operating at a high level of rotational energy. The throttle was noted in the closed position, consistent with an autorotation event; however, it is possible the pilot may have closed the throttle just prior to, or during, the impact sequence. The student pilot had received about 120 hours of helicopter flight training over the 3 1/2-year period prior to the accident. (The pilot's flight logbook had been defaced, thus an accurate assessment of his total flight experience was not possible.) During that time, he had used the services of about nine flight instructors, with only the last instructor endorsing him for solo flight about 2 weeks before the accident. The accident flight was most likely his second solo flight in the accident helicopter. Acquaintances and previous instructors recounted that the pilot often exhibited poor decision-making traits, was headstrong, stubborn, and overconfident. Although the pilot performed maintenance and unapproved modifications to the helicopter, the modifications did not appear to have been causal to the accident, and a postaccident examination did not reveal any anomalies with the airframe or engine that would have precluded normal operation.

The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.