Airworthiness Directive 2021-13711
one-timeAirworthiness Directives; Leonardo S.p.a. (Type Certificates Previously Held by Agusta S.p.A. and AgustaWestland S.p.A.) Helicopters
What this AD requires
The FAA is adopting a new airworthiness directive (AD) for Leonardo S.p.a. (Type Certificate previously held by Agusta S.p.A.) Model AB139 and AW139 helicopters and Leonardo S.p.a. (Type Certificate previously held by AgustaWestland S.p.A.) Model AW189 helicopters. This AD was prompted by reports of missing lock wire and loose fasteners. This AD requires a one-time inspection of the main rotor (M/R) slip ring and depending on the outcome, removing the M/R slip ring from service, removing screws and washers from service, applying torque, installing lock wire, and re-identifying the M/R slip ring. This AD also prohibits the installation of certain M/R slip rings. The FAA is issuing this AD to address the unsafe condition on these products.
Which aircraft AD 2021-13711 applies to
Applies to helicopters with a main rotor (M/R) slip ring, P/N 4G6220V00151, with a serial number up to and including S/N 0141, except those marked with an 'L' following the S/N, installed.
Whether AD 2021-13711 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:
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.