Airworthiness Directive · Amendment 39-23251 · Rotorcraft tail boom
Airbus Helicopters Deutschland GmbH (AHD) Helicopters
This AD applies to Airbus Helicopters Deutschland GmbH (AHD) Model EC135P1, EC135P2, EC135P2+, EC135P3, EC135T1, EC135T2, EC135T2+, EC135T3, and EC635T2+ helicopters, certificated in any category with mounting ring frame X9227, part number (P/N) L535H2120301, L535H2120303, or L535H2120304, installed, except those with frame reinforcement P/N L535H2100201 or L535H2100202 installed.
Note 1 to paragraph (c): Helicopters with an EC135P3H designation are Model EC135P3 helicopters. Helicopters with EC135T3H designation are Model EC135T3 helicopters.
The FAA is superseding Airworthiness Directive (AD) 2014-13- 09, which applied to certain Airbus Helicopters Deutschland GmbH (AHD) helicopters Model EC135P1, EC135P2, EC135P2+, EC135T1, EC135T2, and EC135T2+ helicopters. AD 2014-13-09 required repetitive visual inspections of the ring frame X9227 for a crack, and if there is a crack, replacing the ring frame. Since the FAA issued AD 2014-13-09, AHD Helicopters determined that this unsafe condition also applies to AHD Model EC135P3 and EC135T3 helicopters. This AD continues to require some of the actions required by AD 2014-13-09 and expands the applicability by including AHD Model EC135P3 and EC135T3 helicopters and also reduces the compliance time for the repetitive inspections. This AD also allows the modification of the ring frame X9227 as terminating action for the repetitive visual inspections. The FAA is issuing this AD to address the unsafe condition on these products.
Except as specified in paragraphs (h) and (i) of this AD: Perform all required actions within the compliance times specified in, and in accordance with, European Union Aviation Safety Agency (EASA) AD 2025-0174R1, dated September 22, 2025 (EASA AD 2025-0174R1).
(1) Where EASA AD 2025-0174R1 refers to its effective date or the effective date of August 19, 2025 [the effective date of EASA AD 2025-0174], this AD requires using the effective date of this AD.
(2) Where EASA AD 2025-0174R1 specifies compliance in terms of flight hours, this AD requires using hours time-in-service.
(3) Where paragraph (2) of EASA AD 2025-0174R1 specifies to contact AHD for approved repair instructions and accomplish those actions accordingly, this AD requires accomplishing those actions using a method approved by the Manager, International Validation Branch, FAA; EASA; or AHD's EASA Design Organization Approval (DOA). If approved by the DOA, the approval must include the DOA-authorized signature.
(4) This AD does not require compliance with paragraph (3) of EASA AD 2025-0174R1. This AD considers that modification an optional action and does not require it.
(5) Where the material referenced in EASA AD 2025-0174R1 specifies “if necessary, use a flashlight. A magnifying glass (at least x10 magnification) can be used”, this AD requires replacing that text with “use a light source and at least 10X magnification”.
(6) Where paragraph (5) of EASA AD 2025-0174R1 specifies that modification of a helicopter as required by paragraph (3) of EASA AD 2025-0174R1 constitutes a terminating action for the repetitive inspections as required by paragraph (1) of EASA AD 2025-0174R1, this AD considers that modification an optional action and does not require this action. For this AD, the modification terminates the repetitive inspection requirement.
(7) This AD does not adopt the “Remarks” section of EASA AD 2025-0174R1.
Although the material referenced in EASA AD 2025-0174R1 specifies to submit certain information to the manufacturer, this AD does not require that action.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
