Airworthiness Directive 2021-27709

recurring
AD 2021-27709 · 2021-12-21 · airframe

Airworthiness Directives; De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Airplanes

What this AD requires

The FAA is superseding Airworthiness Directive (AD) 2017-19- 09, which applied to certain De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Model DHC-8-400 series airplanes. AD 2017-19-09 required modifying the nose landing gear (NLG) shock strut assembly. This new AD requires repetitive lubrications of the trailing arm of the NLG. This new AD also requires revising the existing maintenance or inspection program to include new and revised airworthiness limitations (life limits for certain bolts). This AD was prompted by reports of a certain bolt being found missing or having stress corrosion cracking. The FAA is issuing this AD to address the unsafe condition on these products.

Repetitive inspection. Re-inspect every 3 months. The next-due date/hours depend on this aircraft’s time in service — a records report computes it from the logbooks.

Which aircraft AD 2021-27709 applies to

MakesDe Havilland Aircraft Of Canada Limited
ModelsDHC-8-401, DHC-8-402, DHC-8
Serial-conditional — narrows to serials 4001–4001, 4003–?.

Applies to serial number 4001, and serial numbers 4003 and subsequent.

Whether AD 2021-27709 actually applies to your aircraft (by serial and installed parts) and whether it’s already complied with comes from that aircraft’s records.

How AD compliance is recorded

A valid compliance record (14 CFR 43.9) states:

Method of complianceThe specific action taken (inspected, replaced, modified) and to what revision.
DateWhen the work was done.
Aircraft timeTotal time in service / tach at compliance — how recurring next-due is computed.
Signature & certificateThe A&P/IA who returned it to service, with certificate number.
Is AD 2021-27709 complied with on your aircraft?

Tailplate reads a tail number’s logbooks and matches every applicable AD — including this one — to its compliance evidence, with recurring next-due dates computed.

Look up a tail number →Read the full directive (Federal Register)

Applicability is derived from the FAA directive corpus and is advisory, not a legal airworthiness determination. Compliance is established only from an aircraft’s actual records.