AD 2021-10-10 Requires Repetitively Inspecting The MGB Particle Detector And The MGB Bottom Housing

The FAA is adopting a new airworthiness directive (AD) for all Airbus Helicopters Model SA330J helicopters.

This AD was prompted by the failure of a second stage planet gear installed in the main gearbox (MGB). This AD requires repetitively inspecting the MGB particle detector and the MGB bottom housing (oil sump) for metal particles,  analyzing any metal particles that are found, and replacement of the MGB if necessary, as specified in a European Aviation Safety Agency (now European Union Aviation Safety Agency) (EASA) AD, which is incorporated by reference. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective June 24, 2021.

Supplementary Information: The EASA, which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2018-0272, dated December 13, 2018 (EASA AD 2018-0272) (also referred to as the Mandatory Continuing Airworthiness Information, or the MCAI), to correct an unsafe condition for all Airbus Helicopters Model SA330J helicopters.

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to all Airbus Helicopters Model SA330J helicopters. The NPRM published in the Federal Register on March 2, 2021 (86 FR 12127). The NPRM was prompted by the failure of a second stage planet gear installed in the MGB. The NPRM proposed to require repetitively inspecting the MGB particle detector and the MGB bottom housing (oil sump) for metal particles, analyzing any metal particles that are found, and replacement of the MGB if necessary, as specified in an EASA AD.

The FAA is issuing this AD to address failure of an MGB second stage planet gear, which could result in failure of the MGB and subsequent loss of control of the helicopter. See the MCAI for additional background information.

FMI: www.regulations.gov