Is AD 2002-21-51 a recurring Airworthiness Directive?

No — AD 2002-21-51 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2002-21-51 apply to?

AD 2002-21-51 applies to Eurocopter. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2002-21-51

one-time

Official AD 2002-21-51 · FR doc 02-31751 · 2002-12-18 · airframe

Airworthiness Directives; Eurocopter France Model AS355E, F, F1, F2, and N Helicopters

What this AD requires

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2002-21-51, which was sent previously to all known U.S. owners and operators of Eurocopter France (ECF) helicopters by individual letters. This AD requires certain checks of the magnetic chip detector plug (chip detector) for any metal particles and the main gearbox (MGB) oil-sight glass for dark-colored oil. If any of these are present, the AD requires inspecting the lubrication pump (pump) and, if necessary, replacing the MGB and the pump with an airworthy MGB and pump. Also, this AD requires that a different MGB or pump with any time-in-service (TIS) must meet the requirements of this AD before being installed. This AD was prompted by four reports of malfunctions of the MGB pump. The actions specified by this AD are intended to prevent failure of the MGB pump, seizure of the MGB, loss of drive to an engine and main rotor, and subsequent loss of control of the helicopter.

Which aircraft AD 2002-21-51 applies to

MakesEurocopter

Daily/10-hr-TIS check of main gearbox (MGB) magnetic chip detector and oil-sight glass per Eurocopter France Alert Telex 05.00.40; if metal particles or dark oil found, inspect the MGB pump, and replace the MGB and pump with airworthy units before further flight if crank pin play, bushing wear, gear pinion offset, metal chips, or excessive wear are found. Specific model/serial applicability not captured in this text slice.

Whether AD 2002-21-51 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 2002-21-51 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.