Is AD 99-23-17 a recurring Airworthiness Directive?

No — AD 99-23-17 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 99-23-17 apply to?

AD 99-23-17 applies to Eurocopter France — models AS-332C, AS-332L, AS-332L1, AS-332. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 99-23-17

one-time

Official AD 99-23-17 · FR doc 99-29611 · 1999-11-16 · airframe

Airworthiness Directives; Eurocopter France Model AS 332C, L, and L1 Helicopters

What this AD requires

This amendment adopts a new airworthiness directive (AD), applicable to Eurocopter France Model AS 332C, L, and L1 helicopters, that requires a one-time inspection of the length of the main gearbox epicyclic module upper casing bearing attachment bolts (attachment bolts), and if they exceed a certain length, replacing the epicyclic module to preclude a potential interference between the attachment bolts and the 2nd stage planet gear cage web. This amendment is prompted by a report of interference between the attachment bolts and the second stage planet gear cage web of the epicyclic module in the main gearbox. The actions specified by this AD are intended to prevent failure of the second stage planet gear of the main gearbox, loss of main rotor drive and subsequent loss of control of the helicopter.

Which aircraft AD 99-23-17 applies to

MakesEurocopter France

ModelsAS-332C, AS-332L, AS-332L1, AS-332

Serial-conditional — narrows to serials M100–M689, M3000–M3048.

Part-conditional — 332A32-2007-00, 332A32-2007-01.

Applies only to helicopters with epicyclic module P/N 332A32-2007-00 or -01 installed; the serial numbers listed (prefix 'M') are the installed module's serial numbers, not the helicopter's.

Whether AD 99-23-17 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 99-23-17 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.