FAA issues Emergency ED after cracks seen in elevator auxiliary spar on DHC-3s
The Federal Aviation Administration (FAA) issued an Emergency Airworthiness Directive (AD) October 4, 2022 for Viking Air Limited (type certificate previously held by Bombardier Inc. and de Havilland, Inc.) Model DHC-3 airplanes. The Emergency AD was prompted by multiple recent reports of cracks in the left -hand elevator auxiliary spar.
File photo of DHC-3 Turbine Otter, N725TH, that crashed in Mutiny Bay in Washington state September 4. Photo from FlightAware.com
The FAA’s analysis of these reports indicates that immediate AD action is warranted. The FAA is issuing this AD to detect and address cracks, corrosion, and previous repairs to the left-hand elevator auxiliary spar. The unsafe condition, if not addressed, could result in elevator flutter leading to elevator failure, with consequent loss of control of the airplane.
This AD requires repetitive detailed visual inspections of the entire left-hand elevator auxiliary spar for cracks, corrosion, and previous repairs, and depending on the findings, replacement of the left-hand elevator auxiliary spar. This AD also requires sending the inspection results to the FAA.
As an interim action, the FAA is issuing this Emergency AD, as a result of the recent reports, to mandate an inspection of the left-hand elevator auxiliary spar and replacement if necessary.
No reference was made to the fatal crash of a Friday Harbor Seaplane at Mutiny Bay September 4, 2022. Ten people and an unborn baby perished in the crash. As of October 8, seven bodies have been recovered.
The FAA has coordinated with Transport Canada, which is the aviation authority for Canada. CF-2018-04), which includes a requirement for inspecting elevator assemblies for corrosion.
The full EAD is posted on the FAA website.
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