De Havilland DHC-3 N725TH

Summary

On 4 September 2022 at about 22:09 local time, a De Havilland DHC-3 registered N725TH, operated by West Isle Air, was involved in an accident near Freeland, Washington, United States. 10 people were on board and 10 died. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

4 September 2022 at 22:09

Classification

Accident

Location

Freeland, Washington, United States

Coordinates

47.9903, -122.5850

Aircraft

De Havilland DHC-3

Registration

N725TH

Category

Airplane

Year built

1967

Engines

1

Operator

West Isle Air

Operating rule

Part 135: Air Taxi & Commuter

Phase of flight

Not recorded

Route

Friday Harbor → Renton

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

DCA22MA193

10 people died.

The in-flight unthreading of the clamp nut from the horizontal stabilizer trim actuator barrel due to a missing lock ring, which resulted in the horizontal stabilizer moving to an extreme trailing-edge-down position rendering the airplane’s pitch uncontrollable.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

HISTORY OF FLIGHTOn September 4, 2022, about 1509 Pacific daylight time, a float-equipped de Havilland DHC-3 (Otter), N725TH, was destroyed when it impacted the water in Mutiny Bay, near Freeland, Washington, and sank. The pilot and nine passengers were fatally injured. The airplane was owned by Northwest Seaplanes, Inc., and operated as a Title 14 Code of Federal Regulations (CFR) Part 135 scheduled passenger flight by West Isle Air dba Friday Harbor Seaplanes. The flight originated at Friday Harbor Seaplane Base (W33), Friday Harbor, Washington, with an intended destination of Will Rogers Wiley Post Memorial Seaplane Base (W36), Renton, Washington. Visual meteorological conditions prevailed at the time of the accident.

Quoted verbatim from the NTSB record.