Is AD 2020-03-21 a recurring Airworthiness Directive?

Yes — AD 2020-03-21 requires a repetitive inspection every 3 months. Next-due depends on the aircraft's time in service.

Which aircraft does AD 2020-03-21 apply to?

AD 2020-03-21 applies to Bombardier — models BD-700-1A10, BD-700-1A11, BD-700. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2020-03-21

recurring

Official AD 2020-03-21 · FR doc 2020-03924 · 2020-02-26 · airframe

Airworthiness Directives; Bombardier, Inc, Airplanes

What this AD requires

The FAA is adopting a new airworthiness directive (AD) for certain Bombardier, Inc., Model BD-700-1A10 and BD-700-1A11 airplanes. This AD was prompted by reports that main landing gear (MLG) trailing arm assemblies were found with compromised paint finish and corrosion on the axle bore inner diameters due to improper removal of contaminants during manufacturing. This AD requires a one-time inspection to determine if an affected MLG trailing arm assembly is installed, repetitive detailed inspections of the inner diameter of the affected MLG trailing arm assembly axle bore for surface finish discrepancies, corrective actions if necessary, and eventual replacement of primer and paint and application of corrosion preventive compound on the inner diameter of all affected MLG trailing arm assembly axle bores, which terminates the repetitive inspections. 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 2020-03-21 applies to

MakesBombardier

ModelsBD-700-1A10, BD-700-1A11, BD-700

Serial-conditional — narrows to serials 9001–9879, 9998–9998, 60001–?.

Whether AD 2020-03-21 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 compliance — The specific action taken (inspected, replaced, modified) and to what revision.

Date — When the work was done.

Aircraft time — Total time in service / tach at compliance — how recurring next-due is computed.

Signature & certificate — The A&P/IA who returned it to service, with certificate number.

Is AD 2020-03-21 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.