Airworthiness Directive · Amendment 39-21829 · Main rotor system
Airbus Helicopters
This AD applies to Airbus Helicopters Model EC120B helicopters, certificated in any category, having an affected part as defined in European Union Aviation Safety Agency (EASA) AD 2021-0046, dated February 12, 2021 (EASA AD 2021-0046).
The FAA is superseding Airworthiness Directive (AD) 2021-04- 21, which applies to certain Airbus Helicopters Model EC120B helicopters. AD 2021-04-21 required an inspection of the attachment bolts of the main rotor (MR) hub scissors assembly for discrepancies and repair if necessary; part marking of the attachment bolts of the MR hub scissors assembly; and repetitive inspections of the part marking of the attachment bolts, and repair if necessary. This AD continues to require the actions in AD 2021-04-21; and also requires part marking of the washer, scissor branch, and mast ring of the corresponding nut side, and repetitive inspections of the additional part markings and repair if necessary; as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. This AD was prompted by a report of broken and bent attachment bolts of the MR hub scissors assembly and a determination that additional part markings of the washer, scissor branch, and mast ring of the corresponding nut side, and repetitive inspections of those part markings, are necessary to detect any rotation. The FAA is issuing this AD to address the unsafe condition on these products.
Except as specified in paragraph (h) of this AD: Comply with all required actions and compliance times specified in, and in accordance with, EASA AD 2021-0046.
(1) Where EASA AD 2021-0046 refers to its effective date, this AD requires using the effective date of this AD.
(2) Where EASA AD 2021-0046 refers to September 05, 2018 (the effective date of EASA AD 2018-0186), this AD requires using May 7, 2021 (the effective date of AD 2021-04-21).
(3) This AD does not mandate compliance with the “Remarks” section of EASA AD 2021-0046.
(4) Where the service information referenced in EASA AD 2021-0046 specifies to discard certain parts, this AD requires removing those parts from service.
(5) Where EASA AD 2021-0046 refers to flight hours (FH), this AD requires using hours time-in-service.
(6) Paragraphs (3) and (4) of EASA AD 2021-0046 refer to “discrepancies.” For this AD, discrepancies include corrosion, fretting, wear, cracking, bolt play, twist, shearing, rupture, and bolt tightening torque.
(7) Where EASA AD 2021-0046 specifies to contact the manufacturer for repair instructions, this AD requires the repair to be done in accordance with a method approved by the Manager, General Aviation and Rotorcraft Section, International Validation Branch, FAA; or EASA; or Airbus Helicopter's EASA Design Organization Approval (DOA). If approved by the DOA, the approval must include the DOA-authorized signature.
(8) Paragraph (5) of EASA AD 2021-0046 specifies to report inspection results to Airbus Helicopters within a certain compliance time. For this AD, report inspection results at the applicable time specified in paragraph (h)(8)(i) or (ii) of this AD.
(i) If the inspection was done on or after May 7, 2021 (the effective date of AD 2021-04-21): Submit the report within 30 days after the inspection.
(ii) If the inspection was done before May 7, 2021 (the effective date of AD 2021-04-21): Submit the report within 30 days after May 7, 2021.
