The NTSB says witnesses told investigators a turbine Otter seaplane operated by Friday Harbor Seaplane Tours spiraled vertically into Puget Sound on a scheduled flight from Friday Harbor to Renton, Washington. All 10 people onboard died. The NTSB released its preliminary report into the Sept. 4 accident in Mutiny Bay, north of Seattle, on Saturday. The NTSB said that after climbing slightly, the aircraft entered a vertical descent to the water.
“Several witnesses described the airplane as ‘spinning,’ ‘rotating,’ or ‘spiraling’ during portions of the steep descent,” the report says. Maintenance was up to date and plane had undergone a 100-hour inspection three days before the crash, in which a water rudder retract cable was replaced. In the previous inspection on Aug. 16, the NTSB says “the horizontal stabilizer hinge bolts, a right-hand engine ignitor, and a left-hand float locker latch were replaced.” The pilot had been flying the aircraft for five years and was properly certified. The wreckage has been located and will be raised with the help of the Navy.