Is AD 99-24-18 a recurring Airworthiness Directive?

Yes — AD 99-24-18 requires a repetitive inspection every 50 hours. Next-due depends on the aircraft's time in service.

Airworthiness Directive 99-24-18

Q: Which aircraft does AD 99-24-18 apply to?

AD 99-24-18 applies to Eurocopter France — models AS-350B, AS-350B1, AS-350B2, AS-350B3, AS-350BA, AS-350D, AS-355E, AS-355F. Serial/part conditions may narrow it to specific aircraft.

recurring

Official AD 99-24-18 · FR doc 99-30797 · 1999-11-30 · airframe

Airworthiness Directives; Eurocopter France Model AS-350B, B1, B2, B3, BA, and D, and AS-355E, F, F1, F2, and N Helicopters

What this AD requires

This amendment supersedes an existing airworthiness directive (AD), applicable to Eurocopter France Model AS-350B, B1, B2, B3, BA, and D, and AS-355E, F, F1, F2, and N helicopters, that requires inspecting certain versions of the tail rotor spider plate bearing (bearing) for the proper rotational torque, axial play, and any brinelling of the bearing. This amendment has the same inspection requirements as the current AD. Also, this AD expands the applicability to include additional part numbers (P/N's) and reduces the initial and recurring inspection compliance times. This amendment is prompted by additional reports of deterioration of the bearing. The actions specified by this AD are intended to prevent seizure of the bearing, loss of tail rotor control, and subsequent loss of control of the helicopter.

Repetitive inspection. Re-inspect every 50 hours. The next-due date/hours depend on this aircraft’s time in service — a records report computes it from the logbooks.

Which aircraft AD 99-24-18 applies to

MakesEurocopter France

ModelsAS-350B, AS-350B1, AS-350B2, AS-350B3, AS-350BA, AS-350D, AS-355E, AS-355F, AS-355F1, AS-355F2, AS-355N, AS-350, AS-355

Part-conditional — 350A33-2004-00, 350A33-2004-01, 350A33-2004-02, 350A33-2004-03, 350A33-2004-05, 350A33-2009-00, 350A33-2009-01.

Applies only to helicopters with tail rotor spider assembly P/N 350A33-2004-00, -01, -02, -03, -05, or 350A33-2009-00 or -01 installed, and which do not incorporate MOD 076551.

Whether AD 99-24-18 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 99-24-18 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.