Airworthiness Directive · Amendment 39-19419 · Hydraulic power
Airbus SAS Airplanes
This AD applies to all Airbus SAS Model A350-941 airplanes, certificated in any category.
We are adopting a new airworthiness directive (AD) for all Airbus SAS Model A350-941 airplanes. This AD was prompted by a report of an overheat failure mode of the hydraulic engine-driven pump, which could cause a fast temperature rise of the hydraulic fluid. This AD requires modifying the hydraulic monitoring and control application (HMCA) software. We are issuing this AD to address the unsafe condition on these products.
(1) Group 1 airplanes are those on which the hydraulic monitoring and control application (HMCA) software (SW) S4.2 is not installed.
(2) Group 2 airplanes are those on which HMCA SW S4.2 is installed in production by embodiment of Mod 112090 or installed in-service as specified in Airbus Service Bulletin A350-29-P012.
For Group 1 airplanes: Within 30 days after the effective date of this AD, modify the HMCA software by installing HMCA SW S4.2, in accordance with the Accomplishment Instructions of Airbus Service Bulletin A350-29-P012, Revision 01, dated February 1, 2018. Where paragraphs 3.C.(1)(a) and 3.C.(2)(a) of Airbus Service Bulletin A350-29-P012, Revision 01, dated February 1, 2018, identify “SOFTWARE-**” and indicate that the “Software becomes” new software: For purposes of this AD, the software titles/descriptions might not match exactly with the airplane and the service information; the old and new software titles/descriptions are for reference only as an aid to operators.
At the applicable time specified in paragraph (i)(1) or (i)(2) of this AD: No person may install HMCA software prior to HMCA SW S4.2 on any airplane.
(1) For Group 1 airplanes: After accomplishment of the modification required by paragraph (h) of this AD.
(2) For Group 2 airplanes: As of the effective date of this AD.
Installation of an HMCA SW standard approved after the effective date of this AD is acceptable for compliance with the corresponding actions required by paragraph (h) of this AD, provided the conditions required by paragraphs (j)(1) and (j)(2) of this AD are met.
(1) The HMCA SW standard must be approved by the Manager, International Section, Transport Standards Branch, FAA; the European Aviation Safety Agency (EASA); or Airbus SAS's EASA Design Organization Approval (DOA). If approved by the DOA, the approval must include the DOA-authorized signature.
(2) The installation must be accomplished in accordance with the modification instructions approved by the Manager, International Section, Transport Standards Branch, FAA; the EASA; or Airbus SAS's EASA DOA. If approved by the DOA, the approval must include the DOA-authorized signature.
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.
Aircraft
