NTSB: Turbine Otter Nosedived into Bay

 - September 19, 2022, 12:20 PM
The NTSB is collecting the wreckage of this float-equipped de Havilland Canada Turbine Otter, N725TH, that crashed into Puget Sound, Washington, on September 4. (Photo: FlightAware)

According to the NTSB preliminary report issued Friday, witnesses that observed the chartered De Havilland DHC-3 Turbine Otter plunge into Mutiny Bay, Washington, on September 4 told investigators that the single-engine airplane “was in level flight [at about 800 feet msl] before it entered a slight climb, then pitched down in a near-vertical descent.” The crash killed the pilot and all nine passengers aboard. The weather was day VMC with light wind.

Several witnesses described the airplane as “spinning,” “rotating,” or “spiraling.” The airplane continued in a nose-low, near-vertical descent until it hit the water, the report noted. One witness said he did not hear any “pitch change” in engine/propeller noise. 

The accident occurred during the pilot’s second Part 135 tour flight of the day—from Friday Harbor Seaplane Base to Renton Municipal Airport. The pilot had logged 4,686 total flight hours as of May 31 and began flying the DHC-3 in 2017. Total time in the type has not been determined. He received training in emergency procedures in May 2022 and an aircraft competency check in June 2021.

The airplane’s most recent 100-hour inspection was performed on September 1. Included at that time were inspections required by airworthiness directives for control column lower assembly and elevator control tabs. Also, a left-hand rudder retract cable was replaced. The aircraft was not, nor required to be, equipped with an FDR or CVR.

The main recovery effort to raise the wreckage is expected to begin on September 26.