Airworthiness Directive · Amendment 39-18143 · Oxygen
Zodiac Aerotechnics (Formerly Intertechnique Aircraft Systems) Oxygen Mask Regulators
This AD applies to Zodiac Aerotechnics (formerly Intertechnique Aircraft Systems) flightcrew oxygen mask regulators, all part number (P/N) MA10, MC10, MC20, MF10, MF20, MLC20, MLD20, MRA005, MRA022, and MRA023 series; certificated in any category; installed on, but not limited to, airplanes manufactured by Airbus, ATR, BAE Systems (Type Certificate previously held by British Aerospace), Boeing, Bombardier (Type Certificate previously held by Canadair, De Havilland Canada), Cessna, Dassault, EADS CASA, EMBRAER, Gulfstream, Hawker Beechcraft (Type Certificate previously held by Raytheon, Beech), Israel Aircraft Industries (IAI), McDonnell Douglas, Piaggio, Pilatus, Piper, and SOCATA.
We are adopting a new airworthiness directive (AD) for certain Zodiac Aerotechnics (formerly Intertechnique Aircraft Systems) oxygen mask regulators. This AD was prompted by a report of a malfunctioning mask having an inflatable harness with a high premature rupture rate due to defective silicon. This AD requires inspecting and replacing defective harnesses with new or modified serviceable units. We are issuing this AD to detect and correct defective harnesses, which could lead, in case of a sudden depressurization event, to a harness rupture, thereby providing inadequate protection against hypoxia and possibly resulting in unconsciousness of the affected flightcrew member and consequent reduced control of the airplane.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
Except as provided by paragraph (i) of this AD: Within 24 months after the effective date of this AD, inspect the inflatable harness fitted to each flightcrew oxygen mask regulator to determine if the inflatable harness is installed with a part number and a batch number identified in Appendix I of Zodiac Aerospace Service Bulletin MXH-35-240, Revision 7, dated September 1, 2011 (for all airplanes other than Bombardier airplanes); or Appendix I of Zodiac Aerospace Service Bulletin MXH-35-241, Revision 3, dated June 23, 2011 (for Bombardier airplanes).
Note 1 to paragraph (g) of this AD: Referring only to Appendix II of Zodiac Aerospace Service Bulletin MXH-35-240, Revision 7, dated September 1, 2011; or Appendix II of Zodiac Aerospace Service Bulletin MXH-35-241, Revision 3, dated June 23, 2011; to identify a specific oxygen mask regulator is insufficient to demonstrate that the inflatable harness fitted to that oxygen mask regulator is not listed in Appendix I of Zodiac Aerospace Service Bulletin MXH-35-240, Revision 7, dated September 1, 2011; or Appendix I of Zodiac Aerospace Service Bulletin MXH-35-241, Revision 3, dated June 23, 2011.
If during the inspection required by paragraph (g) of this AD, an inflatable harness has a part number and batch number identified in Appendix I of Zodiac Aerospace Service Bulletin MXH-35-240, Revision 7, dated September 1, 2011 (for all airplanes other than Bombardier airplanes); or Appendix I of Zodiac Aerospace Service Bulletin MXH-35-241, Revision 3, dated June 23, 2011 (for Bombardier airplanes): Within 24 months after the effective date of this AD, replace the inflatable harness with a new or re-identified harness, in accordance with the Accomplishment Instructions of Zodiac Aerospace Service Bulletin MXH-35-240, Revision 7, dated September 1, 2011 (for all airplanes other than Bombardier airplanes); or Zodiac Aerospace Service Bulletin MXH-35-241, Revision 3, dated June 23, 2011 (for Bombardier airplanes).
Oxygen mask regulators having a date of manufacturing (DMF) code of November 2008 (112008 or 11-08) or earlier, and those with a DMF code of January 2011 (012011 or 01-11) or later; and those having a part number listed in paragraph 1.A.(4), “Not Concerned Equipment,” of Zodiac Aerospace Service Bulletin MXH-35-240, Revision 7, dated September 1, 2011, are excluded from the inspection and replacement requirements of paragraphs (g) and (h) of this AD, provided it can be demonstrated that the inflatable harness has not been replaced on those masks with an inflatable harness having a part number and batch number identified in Appendix I of the applicable service information specified in paragraph (i)(1) or (i)(2) of this AD. A review of airplane delivery or maintenance records is acceptable to make the determination specified in this paragraph, if the part number and batch number of the harness assembly, and the DMF code of the mask assembly, can be conclusively determined from that review.
(1) Zodiac Aerospace Service Bulletin MXH-35-240, Revision 7, dated September 1, 2011 (for all airplanes other than Bombardier airplanes).
(2) Zodiac Aerospace Service Bulletin MXH-35-241, Revision 3, dated June 23, 2011 (for Bombardier airplanes).
For the purpose of this AD, Bombardier airplanes include airplanes previously manufactured by Canadair or by De Havilland Canada.
