TailplateTailplate
Run a report

Airworthiness Directive 2018-04-11

one-time
Official AD 2018-04-11 · FR doc 2018-03929 · 2018-03-01 · airframe

Airworthiness Directives; Agusta S.p.A. Helicopters

What this AD requires

We are adopting a new airworthiness directive (AD) for Agusta S.p.A. Model AB139 and Model AW139 helicopters. This AD requires inspecting the thickness of the tail gearbox (TGB) central housing (housing). This AD was prompted by reports that the housing thickness does not conform to its type design. The actions of this AD are intended to detect and correct an unsafe condition on these products.

Which aircraft AD 2018-04-11 applies to

MakesAgusta S.P.A.
ModelsAB139, AW139
Part-conditional — 3T6522A00239, 3T6522A00242, 3T6522A00243, 3T6522A00246, 3T6522A05144, 3T6522A05146.

Applies only to helicopters with a TGB assembly P/N 3T6522A00239, 3T6522A00242, 3T6522A00243, or 3T6522A00246 that has a central housing P/N 3T6522A05144 or 3T6522A05146, all serial numbers except those listed in Table 1 of Leonardo Helicopters Bollettino Tecnico No. 139-274, dated September 14, 2016.

Whether AD 2018-04-11 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 2018-04-11 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.