Airworthiness Directive 99-27-12
one-timeAirworthiness Directives; Agusta S.p.A. Model A109A and A109A II Helicopters
What this AD requires
This amendment supersedes an existing airworthiness directive (AD), applicable to Agusta Model A109A and A109A II helicopters, that currently requires, before further flight, inspecting any tail rotor blade (blade) with 400 or more hours time-in-service (TIS) for a crack and replacing any cracked blade before further flight. This amendment contains the same requirements as the current AD but corrects the paragraph that requires ``replacing any cracked blade with an unairworthy blade.'' This amendment is prompted by the need to correct the requirement to mandate ``replacing any cracked blade with an airworthy blade.'' The actions specified by this AD are intended to prevent fatigue failure of the blade, loss of the tail rotor, and subsequent loss of control of the helicopter.
Which aircraft AD 99-27-12 applies to
Dye-penetrant and visual (3-5x magnification) inspection of rotor blade for cracks per Agusta S.p.A. Bollettino Tecnico 109-110; replace cracked blade with an airworthy blade. Bulletin numbering suggests Agusta A109 but the model is not explicitly named in this excerpt; specific model list is in a preceding applicability section not captured here.
Whether AD 99-27-12 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.