Is AD 97-15-15 a recurring Airworthiness Directive?

No — AD 97-15-15 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 97-15-15 apply to?

AD 97-15-15 applies to Eurocopter — models SA-365N, SA-365N1, SA-366G1, SA365, SA366. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 97-15-15

one-time

Official AD 97-15-15 · FR doc 98-2969 · 1998-02-06 · airframe

Airworthiness Directives; Eurocopter France Model SA-365N, SA- 365N1, and SA-366G1 Helicopters

What this AD requires

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 97-15-15, which was sent previously to all known U.S. owners and operators of Eurocopter France Model SA-365N, SA-365N1, and SA-366G1 helicopters by individual letters. This AD requires an inspection of the main gearbox magnetic plug (magnetic plug) and the main gearbox oil filter (oil filter) for ferrous chips; vibration measurements, if necessary; and replacement of the main gearbox if a specified quantity of ferrous chips are discovered, or if abnormal vibrations are identified at a certain frequency. This amendment is prompted by two recent reports of cracks found in planetary gear shafts (gear shafts) in main gearboxes that have not been modified in accordance with MOD 077244. The actions specified by this AD are intended to detect cracks in the gear shaft which could lead to failure of the gear shaft, failure of the transmission, and subsequent loss of control of the helicopter.

Which aircraft AD 97-15-15 applies to

MakesEurocopter

ModelsSA-365N, SA-365N1, SA-366G1, SA365, SA366

Applies to SA-365N/SA-365N1 (main gearbox vibration measurement per work card CT 05.53.00.221) and SA-366G1 (work card CT 05.53.00.220) main gearboxes. Requires post-flight magnetic-plug inspection and periodic (not exceeding 12 hrs TIS) oil-filter inspection for ferrous chips; replace gearbox before further flight if chip coverage is equal to or greater than 0.08 in-sq (50 mm-sq) or if ground vibration measurements exceed baseline at 26.07 Hz. Installation of MOD 077244 is terminating action; special flight permits will not be issued.

Whether AD 97-15-15 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 97-15-15 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.