Airworthiness Directive 2021-07-17

recurring
Official AD 2021-07-17 · FR doc 2021-08058 · 2021-04-20 · airframe

Airworthiness Directives; The Boeing Company Airplanes

What this AD requires

The FAA is adopting a new airworthiness directive (AD) for all The Boeing Company Model 737-900ER series airplanes. This AD was prompted by reports of significant corrosion of electrical connectors located in the main landing gear (MLG) wheel well. This AD requires repetitive records checks to determine exposure to certain deicing fluids or repetitive inspections for corrosion of the electrical connectors, and corrective actions if necessary. The FAA is issuing this AD to address the unsafe condition on these products.

Repetitive inspection. Re-inspect every 24 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 2021-07-17 applies to

MakesBoeing
Models737-900ER, 737

Whether AD 2021-07-17 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 2021-07-17 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.