NTSB Preliminary Report, they indicate that they will not open a docket or publish a final report:
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed.
National Transportation Safety Board Aviation Accident Preliminary Report
Location: Steilacoom, WA Accident Number: WPR18FA220
Date & Time: 08/10/2018, 2043 PDT
Registration: N449QX
Aircraft: De Havilland DHC8
Injuries: 1 Fatal
Flight Conducted Under: Unknown
On August 10, 2018, about 2043 Pacific daylight time, a De Havilland DHC-8-402, N449QX, was destroyed when it impacted trees on Ketron Island, near Steilacoom, WA. The noncertificated pilot was fatally injured. The airplane was registered to Horizon Air Industries Inc. and operated by the individual as an unauthorized flight. Visual meteorological conditions prevailed in the area at the time of the accident, and no flight plan was filed. The airplane departed from the Seattle-Tacoma International Airport, Seattle, Washington, about 1932 for an unknown destination. Horizon Air personnel reported that the individual was employed as a ground service agent and had access to the airplanes on the ramp. The investigation of this event is being conducted under the jurisdiction of the Federal Bureau of Investigation (FBI). The NTSB provided requested technical assistance to the FBI, and any material generated by the NTSB is under the control of the FBI. The NTSB does not plan to issue a report or open a public docket.
Aircraft and Owner/Operator Information Aircraft Make: De Havilland Registration: N449QX
Model/Series: DHC8 402
Aircraft Category: Airplane
Amateur Built: No
Operator: Operating Certificate(s) Held: Flag carrier (121)
Meteorological Information and Flight Plan Conditions at Accident Site: Visual Conditions
Condition of Light: Observation Facility, Elevation: KTIW, 292 ft msl
Observation Time: 2053 PDT
Distance from Accident Site: 8 Nautical Miles
Temperature/Dew Point: 18°C / 14°C
Lowest Cloud Condition:
Wind Speed/Gusts, Direction: 7 knots / , 240°
Lowest Ceiling:
Visibility: 10 Miles
Altimeter Setting: 29.98 inches Hg
Type of Flight Plan Filed: None
Departure Point: Seattle, WA (SEA)
Destination:
Wreckage and Impact Information Crew Injuries: 1 Fatal
Aircraft Damage: Destroyed
Passenger Injuries: N/A
Aircraft Fire: On-Ground
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 Fatal
Latitude, Longitude: 47.148056, -122.637500 (est)
Administrative Information Investigator In Charge (IIC): Debra J Eckrote
Additional Participating Persons:
Note: The NTSB traveled to the scene of this accident.
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