Is AD 2021-10-20 a recurring Airworthiness Directive?

No — AD 2021-10-20 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2021-10-20 apply to?

AD 2021-10-20 applies to Atr — models ATR42-500, ATR72-212A, ATR42, ATR72. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2021-10-20

one-time

Official AD 2021-10-20 · FR doc 2021-10257 · 2021-05-14 · airframe

Airworthiness Directives; ATR-GIE Avions de Transport Régional Airplanes

What this AD requires

The FAA is adopting a new airworthiness directive (AD) for certain ATR--GIE Avions de Transport R[eacute]gional Model ATR42-500 and ATR72-212A airplanes. This AD was prompted by reports of temporary loss of all display units and the integrated electronic standby instrument (IESI). This AD requires revising the existing aircraft flight manual (AFM) and applicable corresponding operational procedures to update a systems limitation, limiting dispatch with certain equipment inoperative, performing an operational test of a certain contactor and an electrical test of a certain battery toggle switch, and corrective actions if necessary, as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. The FAA is issuing this AD to address the unsafe condition on these products.

Which aircraft AD 2021-10-20 applies to

MakesAtr

ModelsATR42-500, ATR72-212A, ATR42, ATR72

Applies to airplanes as identified in EASA Emergency AD 2021-0120-E, dated May 3, 2021.

Whether AD 2021-10-20 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 2021-10-20 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.