Is AD 2021-17-01 a recurring Airworthiness Directive?

No — AD 2021-17-01 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2021-17-01 apply to?

AD 2021-17-01 applies to Austro Engine — models E4, E4P. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2021-17-01

one-time

Official AD 2021-17-01 · FR doc 2021-16895 · 2021-08-06 · reciprocating engine

Airworthiness Directives; Austro Engine GmbH Engines

What this AD requires

The FAA is adopting a new airworthiness directive (AD) for all Austro Engine GmbH E4 and E4P model diesel piston engines. This AD was prompted by a report of oil pressure loss on an E4 model diesel piston engine. This AD requires removing a certain oil pump from service and replacing it with a part eligible for installation. The FAA is issuing this AD to address the unsafe condition on these products.

Which aircraft AD 2021-17-01 applies to

MakesAustro Engine

ModelsE4, E4P

Whether AD 2021-17-01 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 2021-17-01 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.