Is AD 2021-20-04 a recurring Airworthiness Directive?

No — AD 2021-20-04 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2021-20-04 apply to?

AD 2021-20-04 applies to Airbus Sas — models A350-941, A350-1041, A350. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2021-20-04

one-time

Official AD 2021-20-04 · FR doc 2021-22198 · 2021-10-13 · airframe

Airworthiness Directives; Airbus SAS Airplanes

What this AD requires

The FAA is adopting a new airworthiness directive (AD) for certain Airbus SAS Model A350-941 and -1041 airplanes. This AD was prompted by a report that during flight tests, the opening of the ram air outlet flaps was found to cause a disturbance of the air flow around the ram air turbine (RAT) when the landing gear (L/G) is extended. This AD requires revising the existing airplane flight manual (AFM) and applicable corresponding operational procedures to provide procedures for all engines failure and L/G gravity extension related to certain software, and installing Airbus temporary quick change (ATQC) V3 for the flight warning system (FWS) software (SW) standard (STD) 6/ 2.0, 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 2021-20-04 applies to

MakesAirbus Sas

ModelsA350-941, A350-1041, A350

Applies to airplanes identified in EASA AD 2021-0061, dated March 5, 2021.

Whether AD 2021-20-04 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 2021-20-04 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.