DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2017-0505; Product Identifier 2017-NE-15-AD; Amendment
39-19472; AD 2018-21-14]
Airworthiness Directives; Zodiac Aerotechnics Oxygen Mask Regulators
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
SUMMARY: We are adopting a new airworthiness directive (AD) for
Zodiac Aerotechnics (Zodiac) oxygen mask regulators. This AD was
prompted by reports that certain silicon harness inflation hoses
installed on certain flight crew quick donning mask harnesses have
shown an unusually high premature rupture rate. This AD requires
inspection and replacement of certain oxygen mask regulator harness
inflation hoses. We are issuing this AD to address the unsafe condition
on these products.
DATES: This AD is effective March 27, 2019.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of March 27,
ADDRESSES: For service information identified in this final rule,
contact Zodiac Aerotechnics, 61 rue Pierre Curie BP 1, 78373 Plaisir,
CEDEX, France; phone: +33 1 6486 6964; email:
Yann.email@example.com. You may view this service information
at the FAA, Engine & Propeller Standards Branch, 1200 District Avenue,
Burlington, MA 01803. For information on the availability of this
material at the FAA, call 781-238-7759. It is also available on the
internet at http://www.regulations.gov by searching for and locating
Docket No. FAA-2017-0505.
Examining the AD Docket
You may examine the AD docket on the internet at http://www.regulations.
gov by searching for and locating Docket No. FAA-2017-
0505; or in person at Docket Operations between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays. The AD docket contains
this final rule, the mandatory continuing airworthiness information
(MCAI), the regulatory evaluation, any comments received, and other
information. The address for Docket Operations (phone: 800-647-5527) is
U.S. Department of Transportation, Docket Operations, M-30, West
Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE,
Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Erin King, Aerospace Engineer,
ACO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone 781-
238-7655; fax: 781-238-7199; email: firstname.lastname@example.org.
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 by adding an AD that would apply to certain Zodiac oxygen mask
regulators. The NPRM published in the Federal Register on September 25,
2017 (82 FR 44539). The NPRM was prompted by reports that certain
silicon harness inflation hoses installed on certain flight crew quick
donning mask harnesses have shown an unusually high premature rupture
rate. The NPRM proposed to require an inspection and replacement of
oxygen mask regulator harness inflation hoses. We are issuing this AD
to address the unsafe condition on these products.
The European Union Aviation Safety Agency (EASA), which is the
Technical Agent for the Member States of the European Community, has
issued EASA AD 2014-0142, Revision 01, dated June 11, 2014 (referred to
after this as ``the MCAI''), to address the unsafe condition on these
products. The MCAI states:
Recent reported occurrences have shown that for harness hoses P/
N 445952, installed on certain flight crew quick donning mask
harnesses (also known as `comfort' harness) having P/N MXH21-1,
suspected silicon batches may have been used during manufacture,
which have shown an unusually high premature rupture rate. The
affected P/N MXH21-1 inflatable harness assembly consists of two
main parts that can be disassembled; the harness itself and the
harness inflation hose, P/N 445952.
This condition, if not detected and corrected, could lead, in
case of a sudden depressurization event, to a harness rupture,
thereby providing inadequate protection against hypoxia of the
affected flight crew member, possibly resulting in unconsciousness
and consequent reduced control of the aeroplane.
You may obtain further information by examining the MCAI in the AD
docket on the internet at http://www.regulations.gov by searching for
and locating Docket No. FAA-2017-0505.
We gave the public the opportunity to participate in developing
this final rule. The following presents the comments received on the
NPRM and the FAA's response to each comment.
Comment To Figure Reference in Service Information
NetJets Aviation, Inc. (NetJets) commented that Accomplishment
Instructions, paragraph 3.A.(1) of Zodiac Aerospace Service Bulletin
(SB) MC10-35-274, Revision 02, dated June 25, 2014, references Figure
3; however, there are only Figures 1 and 2 in this SB.
We agree that Zodiac Aerospace SB MC10-35-274, Revision 02, dated
June 25, 2014, references Figure 3 in error. The FAA, however, is not
responsible for administrative errors in SBs. We did not change this
Request To Revise Part for Installation Eligibility
American Airlines (AA) requested that we revise the phrase in
paragraph (h)(2) of the NPRM from ``inflatable harness assembly'' to
``crew oxygen mask regulator.'' AA reasoned that paragraph 1.A.(1) of
Zodiac Aerospace SB MC10-35-274, Revision 02, dated June 25, 2014,
includes both the inflatable harness assembly part numbers (P/Ns) as
well as the crew oxygen mask regulator P/Ns. The intent is to check the
crew oxygen mask regulator for installation eligibility.
We agree. We revised the paragraphs in this AD that refer to parts
eligible for installation as the ``crew oxygen mask regulator.''
Request To Add Credit for Previous Actions Paragraph
AA and NetJets requested that we add a Credit For Previous Actions
paragraph to this AD. AA asked that we give credit for actions required
by this AD if those actions were performed before the effective date of
this AD using Zodiac Aerospace SB MC10-35-274, Revision 01, dated April
18, 2014, or Original Issue, dated March 19, 2014. NetJets asked that
in addition to the SBs mentioned above, we also give credit for using
EASA AD 2014-0142, Revision 01, dated June 11, 2014, to accomplish the
actions required by this AD. AA reasoned that EASA AD 2014-0142,
Revision 01, dated June 11, 2014, allows for compliance with earlier
revisions of the service information.
We partially agree. We agree to give credit for accomplishing the
required actions if operators used Zodiac Aerospace SB MC10-35-274,
Revision 01, dated April 18, 2014, or Zodiac Aerospace SB MC10-35-274,
Original Issue, dated March 19, 2014, because this meets the intended
safety requirements of this AD. We added a Credit For Previous Actions
paragraph to this AD.
We disagree with revising the AD to allow for previous credit for
performing EASA AD 2014-0142, Revision 01, dated June 11, 2014, because
this is not necessary and is inconsistent with how we draft ADs.
Request To Clarify the Oxygen Mask Regulator Prohibition
AA, NetJets, and United Airlines (United) requested clarification
regarding the oxygen mask regulator prohibition in the Installation
Prohibition paragraph of this AD. The commenters reasoned that
paragraph (h)(1), as proposed in the NPRM, prohibited the installation
of certain oxygen mask regulators; whereas, paragraphs (h)(2) and (3)
in the NPRM describe criteria that allow installation. AA requested
that we remove paragraph (h)(1) of this AD. NetJets requested
clarification and possible rewording of paragraph (h)(1) of this AD.
United suggested rewording and reformatting of paragraph (h)(1) of this
We partially agree. We agree that we need to clarify this AD to
more clearly describe when a flight crew oxygen mask regulator is
eligible for installation. We revised the Installation Prohibition
paragraph by moving paragraphs (h)(2) and (3) into a Definition
paragraph. We also revised paragraph (h)(1) of the NPRM, now paragraph
(h) in the final rule, to allow the installation of certain oxygen mask
regulators when they meet the criteria specified in paragraph (i)(1) of
We disagree with removing paragraph (h)(1) from this AD (paragraph
(h) in the final rule) because oxygen mask regulators with a P/N listed
in Paragraph 1.A.(1) of Zodiac Aerospace SB MC10-35-274, Revision 02,
dated June 25, 2014, cannot be installed unless they meet the criteria
specified in paragraph (i), Definition, of this AD.
Request To Remove Hose Part Numbers
United requested that we clarify references to specific harness
inflation hose P/Ns in the Applicability paragraph, paragraph (c), and
the Required Actions paragraph, specifically paragraphs (g)(2) and (3),
of this AD. United noted that these P/Ns are not identified on the
inflation harness assemblies after the hoses are installed on a crew
oxygen mask assembly. United reasoned that although detailed shop
records would likely itemize the hose P/Ns, they are unaware of any
parts `data plate' or `data tag' on the inflation harness assemblies
that identify the hose P/Ns after they are installed on a crew oxygen
We partially agree. We agree that the hose P/Ns are not required in
the Applicability paragraph of this AD. We revised the applicability,
paragraph (c), of this AD by removing the references to the
installation hose and its P/Ns.
We disagree with removing the hose P/Ns from paragraphs (g)(2) and
(3) of this AD. Although the commenter correctly points out that there
is no data tag or data plate affixed to the hose, these P/Ns are useful
to operators who can determine the hose P/N. Additionally, identifying
the hose P/Ns in this AD is consistent with EASA AD 2014-0142, Revision
01, dated June 11, 2014.
Request To Increase the Compliance Time
United and AA requested, respectively, that we increase the
compliance time from 24 months to 36 or to 48 months. The commenters
reasoned that operators experienced supply issues when trying to comply
with AD 2015-08-07 and many operators requested extensions to the
compliance time. The supply situation was worsened because some oxygen
mask regulator harnesses needed to be replaced because of illegible or
non-existent part marking.
We partially agree. We agree to increase the compliance time to 36
months to ensure that suppliers can provide the parts because of the
possibility there will be supply issues. Zodiac has not been able to
determine inventory because they do not know the number of parts in use
by U.S. operators. Increasing the compliance time by 12 months still
meets the safety objectives of this AD. Our understanding from Zodiac
is that they recommend hose replacement every 72 months, and given that
all of the affected hoses were manufactured between 2008 and 2010, many
of the affected hoses likely have been removed from service.
We disagree with increasing the compliance time to 48 months
because 36 months is sufficient to comply with the required actions of
this AD. Additionally, we do not want to extend, beyond a reasonable
time, the period for which suspect parts can remain on aircraft. We
revised paragraph (g)(1) of this AD to increase the compliance time to
Request To Decrease the Compliance Time
The Airline Pilots Association International (ALPA) requested that
the compliance time decrease from 24 months to 12 months. ALPA reasoned
that greater than 40 months have passed since EASA AD 2014-0142,
Revision 01, dated June 11, 2014, became effective. ALPA also noted
that the required time to comply with the AD is one work-hour. Based on
these factors the compliance time of this AD should be decreased to
We disagree. We note that operators may have difficulty obtaining
replacement parts within a shortened compliance time. Also, the
compliance time of 36 months after the effective date of this AD meets
the safety objectives of this AD. We did not change this AD.
Request To Remove the P/Ns That Are Not Eligible for the "W"
AA and United requested that we remove the reference to inflatable
harness assembly P/Ns that have been re-marked with a ``W'' from the
Installation Prohibition, of this AD. The commenters reasoned that
adding a ``W'' applies only to oxygen mask regulator assemblies that
have inflation harness assemblies, P/N MXH21-31, installed per Zodiac
Aerospace SB MA_B_C_F10-35-260, dated October 19, 2012, or later
We agree. When an oxygen mask is modified per Zodiac SB MA_B_C_F10-
35-260 and marked with a ``W,'' the P/N also changes to MXH21-31.
Therefore, only P/N MXH21-31 is marked with a ``W.'' Paragraph (h)(3)
of the NPRM incorrectly implied that P/N MXH20-1 and P/N MXH21-1 might
also be marked with a ``W.'' We revised this AD by removing the
reference to remarking P/Ns MXH20-1 and MXH21-1 with a ``W.''
Request To Include Inflatable Harness Assemblies Marked With an "I"
AA requested that we include inflatable harness assembly marked
with an ``I'' on the metal bushing to Required Actions, paragraph
(g)(3), of this AD. AA reasoned that inflatable harness assemblies with
an ``I'' on the metal bushings have been inspected and are not affected
by this AD.
We agree. Based on paragraph 2.E. of Zodiac SB MC10-35-274,
Revision 02, dated June 25, 2014, marking an ``I'' on the metal bushing
of the inflatable harness indicates accomplishment of the SB. We have
revised paragraph (g)(3) of this AD to note that inflatable harness
assemblies with metal bushings marked with an ``I'' are not affected by
Request To Delay the Installation Prohibition Start Time
United requested that we add ``within 60 days of the effective date
of this AD'' to the Installation Prohibition of this AD to provide more
time before prohibiting the installation of the affected flight crew
oxygen mask regulators. United reasoned that immediately restricting
the installation of the affected regulators after the effective date of
this AD is a logistical challenge and can be counterproductive. United
is also concerned that material orders will be over abundantly placed
to compensate for not knowing the modification status of their mask
inventory. United believes that offsetting the start of a parts
installation prohibition period would not significantly increase the
We disagree. Given the increased compliance time allowed in
paragraph (g)(1) of this AD, operators should have time to assess their
inventory and make accurate purchases to replace affected parts. It
would not be in the interest of safety to allow the period for which
suspect parts could remain on the aircraft to continue for any period
after this AD is published. We did not change this AD.
We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
this final rule with the changes described previously and minor
editorial changes. We have determined that these minor changes:
[Agr]re consistent with the intent that was proposed in
the NPRM for addressing the unsafe condition; and
Do not add any additional burden upon the public than was
already proposed in the NPRM.
We also determined that these changes will not increase the
economic burden on any operator or increase the scope of this final
Related Service Information Under 1 CFR Part 51
We reviewed Zodiac Aerospace SB MC10-35-274, Revision 02, dated
June 25, 2014. The SB describes procedures for inspecting and
replacing, if necessary, oxygen mask regulator inflatable harnesses.
This service information is reasonably available because the interested
parties have access to it through their normal course of business or by
the means identified in the ADDRESSES section.
Costs of Compliance
We estimate that this AD affects an unknown number of oxygen mask
regulators installed on, but not limited to, various aircraft of U.S.
We estimate the following costs to comply with this AD:
|Date of manufacturing code review
||0.1 work-hours x $85 per hour
||0.3 work-hours x $85 per hour
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, section 106, describes the
authority of the FAA Administrator. Subtitle VII: Aviation Programs,
describes in more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in
Subtitle VII, Part A, Subpart III, Section 44701: ``General
requirements.'' Under that section, Congress charges the FAA with
promoting safe flight of civil aircraft in air commerce by prescribing
regulations for practices, methods, and procedures the Administrator
finds necessary for safety in air commerce. This regulation is within
the scope of that authority because it addresses an unsafe condition
that is likely to exist or develop on products identified in this
This AD is issued in accordance with authority delegated by the
Executive Director, Aircraft Certification Service, as authorized by
FAA Order 8000.51C. In accordance with that order, issuance of ADs is
normally a function of the Compliance and Airworthiness
Division, but during this transition period, the Executive Director has
delegated the authority to issue ADs applicable to engines, propellers,
and associated appliances to the Manager, Engine and Propeller
Standards Branch, Policy and Innovation Division.
This AD will not have federalism implications under Executive Order
13132. This AD will not have a substantial direct effect on the States,
on the relationship between the national government and the States, or
on the distribution of power and responsibilities among the various
levels of government.
For the reasons discussed above, I certify this AD:
(1) Is not a ``significant regulatory action'' under Executive
(2) Is not a ``significant rule'' under the DOT Regulatory Policies
and Procedures (44 FR 11034, February 26, 1979),
(3) Will not affect intrastate aviation in Alaska, and
(4) Will not have a significant economic impact, positive or
negative, on a substantial number of small entities under the criteria
of the Regulatory Flexibility Act.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
Adoption of the Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. The FAA amends Sec. 39.13 by adding the following new airworthiness