Airworthiness Directive 2021-04-13
recurringAirworthiness Directives; Airbus Helicopters
What this AD requires
The FAA is adopting a new airworthiness directive (AD) for all Airbus Helicopters Model AS350B, AS350BA, AS350B1, AS350B2, AS350B3, and AS350D helicopters; Model AS355E, AS355F, AS355F1, AS355F2, AS355N, and AS355NP helicopters; and Model EC130 B4 and EC130 T2 helicopters. This AD requires a one-time inspection to verify the presence and correct installation of the main rotor mast (MRM) upper bearing retaining rings, a repetitive inspection of the sealant bead on the MRM for damage, and corrective actions if necessary. This AD was prompted by a report of a missing retaining ring of the inner race of the MRM upper bearing. The actions of this AD are intended to address an unsafe condition on these products.
Which aircraft AD 2021-04-13 applies to
Whether AD 2021-04-13 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.