Is AD 2015-08-51 a recurring Airworthiness Directive?

No — AD 2015-08-51 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2015-08-51 apply to?

AD 2015-08-51 applies to Enstrom — models F-28A, F-28C, F-28C-2, F-28C-2R, 280C, F-28F, F-28F-R, 280F. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2015-08-51

one-time

Official AD 2015-08-51 · FR doc 2015-11732 · 2015-05-18 · airframe

Airworthiness Directives; The Enstrom Helicopter Corporation

What this AD requires

We are publishing a new airworthiness directive (AD) for Enstrom Helicopter Corporation (Enstrom) Model F-28A, 280, F-28C, F- 28C-2, F-28C-2R, 280C, F-28F, F-28F-R, 280F, 280FX, and 480 helicopters. This AD was sent previously to all known U.S. owners and operators of these helicopters and supersedes Emergency AD (EAD) 2015- 04-51, dated February 12, 2015. This AD requires inspecting certain main rotor spindles (spindles) for cracks and reporting the inspection results to the FAA. This AD is prompted by a fatal accident and reports of spindles with cracks. The actions specified in this AD are intended to detect a crack in a spindle and prevent loss of a main rotor blade and subsequent loss of control of the helicopter.

Which aircraft AD 2015-08-51 applies to

MakesEnstrom

ModelsF-28A, F-28C, F-28C-2, F-28C-2R, 280C, F-28F, F-28F-R, 280F, 280FX, F-28, 280, 480

Serial-conditional — narrows to serials 5001–5006.

Part-conditional — 28-14282-11, 28-14282-13.

Applies to Enstrom F-28A, 280, F-28C, F-28C-2, F-28C-2R, 280C, F-28F, F-28F-R, 280F, and 280FX helicopters (all S/N), and Model 480 helicopters S/N 5001 through 5006, with a main rotor spindle P/N 28-14282-11 or -13 installed, having 1,500 or more hours time-in-service (TIS) or unknown hours TIS. Serial range 5001-5006 applies to Model 480 only. Supersedes Emergency AD 2015-04-51.

Whether AD 2015-08-51 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 2015-08-51 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.