Is AD 2013-20-18 a recurring Airworthiness Directive?

No — AD 2013-20-18 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2013-20-18 apply to?

AD 2013-20-18 applies to Bell — models 412, 412EP, 412CF. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2013-20-18

one-time

Official AD 2013-20-18 · FR doc 2013-24961 · 2013-10-25 · airframe

Airworthiness Directives; Bell Helicopter Textron, Inc. (Bell) Helicopters

What this AD requires

We are superseding Airworthiness Directive (AD) 2009-05-09 for Bell Model 412, 412CF, and 412EP helicopters. AD 2009-05-09 required reidentifying each affected part-numbered main rotor yoke (yoke) on its data plate, reducing the retirement life of the reidentified yoke, and revising the Airworthiness Limitations section of the maintenance manual or the Instructions for Continued Airworthiness (ICAs) accordingly. This new AD retains the requirements of AD 2009-05-09 with the exception of the P/N marking location. This AD was prompted by fatigue analysis that shows the retirement life should be reduced on certain yokes. We are issuing this AD to correct the unsafe condition on these helicopters.

Which aircraft AD 2013-20-18 applies to

MakesBell

Models412, 412EP, 412CF

Part-conditional — 412-010-101-123, 412-010-101-127, 412-010-101-129, 412-010-101-133.

Applies to Model 412 and 412EP helicopters with main rotor yoke P/N 412-010-101-123, -127, -129, or -133 installed; and Model 412CF helicopters with yoke P/N 412-010-101-127 or -129 installed.

Whether AD 2013-20-18 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 2013-20-18 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.