Is AD 2016-21-01 a recurring Airworthiness Directive?

No — AD 2016-21-01 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2016-21-01 apply to?

AD 2016-21-01 applies to Bell — models 430. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2016-21-01

one-time

Official AD 2016-21-01 · FR doc 2016-24741 · 2016-10-14 · airframe

Airworthiness Directives; Bell Helicopter Textron Helicopters

What this AD requires

We are adopting a new airworthiness directive (AD) for certain Bell Helicopter Textron (Bell) Model 430 helicopters. This AD requires establishing a life limit for a certain main rotor hub attachment bolt (bolt) and removing from service each bolt that has met or exceeded its life limit. This AD was prompted by a documentation error that omitted the life limit of a certain part-numbered bolt from the Airworthiness Limitations section of the maintenance manual. The actions of this AD are intended to establish a life limit for a certain part-numbered bolt to prevent failure of a bolt, failure of a main rotor hub, and subsequent loss of control of a helicopter.

Which aircraft AD 2016-21-01 applies to

MakesBell

Models430

Serial-conditional — narrows to serials 49001–49129.

Part-conditional — MS21250-08083.

Applies to helicopters with a main rotor head attachment bolt, P/N MS21250-08083, installed.

Whether AD 2016-21-01 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 2016-21-01 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.