Is AD 2015-20509 a recurring Airworthiness Directive?

No — AD 2015-20509 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2015-20509 apply to?

AD 2015-20509 applies to Bell — models 206L-4, 206L, 407, 427, 429. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2015-20509

one-time

AD 2015-20509 · 2015-08-20 · airframe

Airworthiness Directives; Bell Helicopter Textron Canada (Bell) Helicopters

What this AD requires

We are superseding Airworthiness Directive (AD) 2001-13-51 for Bell Model 206L-4, 407, and 427 helicopters. AD 2001-13-51 required inspecting certain driveshafts for a crack, a loose bolt or nut, or red powder residue and replacing a driveshaft if there is a crack, a loose bolt or nut, or red powder residue. AD 2001-13-51 also required notifying the FAA within 10 days if a crack is found in the driveshaft. This new AD retains the inspection requirement of AD 2001-13-51, expands the applicability to include the Model 429 helicopter, and removes the reporting requirement. This AD is intended to prevent failure of a driveshaft, loss of drive to the main rotor system, and a subsequent emergency landing.

Which aircraft AD 2015-20509 applies to

MakesBell

Models206L-4, 206L, 407, 427, 429

Part-conditional — 206-340-300-105.

Applies to Model 206L-4, 407, 427, and 429 helicopters with an engine-to-transmission driveshaft assembly, P/N 206-340-300-105, installed. Supersedes AD 2001-13-51.

Whether AD 2015-20509 actually applies to your aircraft (by serial and installed parts) and whether it’s already complied with comes from that aircraft’s records.

Supersession

Supersedes AD 2001-13-51.

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 2015-20509 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.