AD 2021-24-17 Airworthiness Directives; Airbus Helicopters Deutschland GmbH Helicopters

This AD applies to Airbus Helicopters Deutschland GmbH Model EC135P1, EC135P2, EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+, and EC135T3 helicopters, certificated in any category, with tail rotor (TR) blade part number (P/N) L642A2002101, L642A2002103, L642A2002104, L642A2002111, or L642A2002112 installed.

Comply with this AD within the compliance times specified, unless already done.

(1) For all model helicopters identified in paragraph (c) of this AD, within 350 hours time-in-service (TIS) after the effective date of this AD, determine the total hours TIS of each TR blade P/N L642A2002101 or P/N L642A2002111 in accordance with paragraph 3.B.2 of the Accomplishment Instructions of Airbus Helicopters Alert Service Bulletin ASB EC135H-04A-002, Revision 1, dated December 21, 2020 (ASB EC135H-04A-002) or paragraph 3.B.2 (version A) or 3.B.4 (version B) of the Accomplishment Instructions of Airbus Helicopters Alert Service Bulletin ASB EC135-04A-014, Revision 1, dated December 21, 2020 (ASB EC135-04A-014) as applicable to your model helicopter. Remove from service any TR blade that has accumulated or exceeded 6,800 total hours TIS. For each TR blade that has accumulated less than 6,800 total hours TIS do the following: (i) Create a component history card or equivalent record to establish a life limit of 6,800 total hours TIS. (ii) Re-identify each TR blade P/N L642A2002101 as P/N L642A2002104 and re-identify each T/R blade P/N L642A2002111 as P/N L642A2002112 by following paragraph 3.B.5 of the Accomplishment Instructions of ASB EC135H-04A-002, or paragraph 3.B.7 of the Accomplishment Instructions of ASB EC135-04A-014 as applicable to your model helicopter. (iii) Thereafter, remove from service any TR blade P/N L642A2002104 or P/N L642A2002112 before it accumulates 6,800 total hours TIS. (2) For Model EC135P1, EC135P2, EC135P2+, EC135T1, EC135T2, and EC135T2+ helicopters with TR blade P/N L642A2002103 that has previously been installed on Model EC135P3 or EC135T3 helicopters, within 350 hours TIS after the effective date of this AD, determine the total hours TIS of the TR blade in accordance with a method approved by the Manager, General Aviation and Rotorcraft Section, International Validation Branch, FAA; or European Union Aviation Safety Agency (EASA); or Airbus Helicopters' EASA Design Organization Approval (DOA). If approved by the DOA, the approval must include the DOA-authorized signature. (3) For Model EC135P3 and EC135T3 helicopters within 350 hours TIS after the effective date of this AD, remove from service any TR blade P/N L642A2002103 before exceeding 6,800 total hours TIS. (4) For Model EC135P3 and EC135T3 helicopters, as of the effective date of this AD, do not install any TR blade P/N L642A2002101, P/N L642A2002103, or P/N L642A2002111 on any helicopter. (5) For Model EC135P1, EC135P2, EC135P2+, EC135T1, EC135T2, and EC135T2+ helicopters, as of the effective date of this AD, do not install any TR blade P/N L642A2002101 or L642A2002111 that has accumulated or exceeded 500 total hours TIS while installed on a Model EC135P3 or EC135T3 helicopter.

This AD was prompted by a notification of certain parts needing a reduced life limit when installed on certain model helicopters. The FAA is issuing this AD to prevent certain part-numbered TR blades from remaining in service beyond their fatigue life. The unsafe condition, if not addressed, could result in fatigue and failure of a TR blade and loss of helicopter control.

None.