The pilot, Stephen Knight, and his wife (and sole passenger) were flying from Inuvik, in Canada's Northwest Territories, to Fairbanks in a Piper PA32 as part of a three aircraft touring group. The aircraft had flown together from California into Canada and then Alaska. The NTSB determined that the pilot's continued operation under visual flight rules into instrumental meteorological conditions likely led "to spatial disorientation, which resulted in a loss of airplane control and in-flight structural failure." Knight was only rated for VFR.
The pilot was apparently a member of the West Valley Flying Club in Palo Alto, Calif. According to the report, the aircraft was owned by LMP Saratoga, also of Palo Alto, and operated by the flying club, which only allows members to use its aircraft. Knight, who held a private pilot's license, had listed 804 hours of total flight time when he last filled out a rental agreement with the flying club in March.
The accident flight originated in Inuvik and, according to the other two pilots, was destined for Fairbanks. The leader of the group told NTSB officials that the accident aircraft was third in the group; the first airplane arrived in Fairbanks uneventfully but the other two planes landed in Fort Yukon after deteriorating weather required an unscheduled fuel stop. Conditions were still marginal after they departed Fort Yukon for Fairbanks and the second aircraft obtained an IFR clearance for Fairbanks. Knight however, told the second pilot he had found "a good VFR track."
Four minutes prior to impact, Knight did request an IFR clearance from Anchorage approach. After being instructed to climb to 7,000 feet, he reported climbing through 6,800 and then the aircraft dropped from radar. It was officially reported as overdue almost 40 minutes later at 5:19 PM. There was no explanation in the report as to why the VFR-only pilot was in the rear of the group.
The NTSB report states that it is "likely that the pilot then lost control of the airplane, and entered a steep spiraling dive from which he was unable to recover. During the dive, the aerodynamic forces increased to the point that the left wing separated from the airplane, which tightened the spiral, and led to the in-flight structural failure of other sections of the airplane."
Group "adventure" flights are becoming more and more common in Alaska and part of a growing trend in aviation travel. Usually comprised of three or more aircraft, they are characterized by pilots who own or rent the planes they operate and do not generally include flight instructors, although there might be "guides" onboard or in the lead aircraft. In June of this year there was a multiple fatality crash in the Cantwell area on a "Let's Fly Alaska" tour group flight. That pilot was also flying under visual flight rules into instrument meteorological conditions.