SEATTLE (AP) — U.S. investigators say a mechanical issue may have caused the seaplane crash that killed 10 people off an island in Washington state last month.
The National Transportation Safety Board is investigating the Sept. 4 crash off Whidbey Island.
Officials said Monday that it appeared a critical part that moved the plane’s horizontal tail stabilizer came apart. The investigators said that part might have failed because a clamp nut unthreaded and rotated due to a missing or improperly installed lock ring.
The plane was a de Havilland Canada DHC-3 Otter turboprop operated by Renton-based Friday Harbor Seaplanes.
It crashed into Puget Sound, killing the pilot and all nine passengers. Six bodies have been recovered.