AD 2021-08-04

[Federal Register Volume 86, Number 75 (Wednesday, April 21, 2021)]
[Rules and Regulations]
[Pages 20621-20625]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2021-08213]



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Rules and Regulations
                                                Federal Register
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Federal Register / Vol. 86, No. 75 / Wednesday, April 21, 2021 / 
Rules and Regulations

[[Page 20621]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0480; Product Identifier 2019-NM-041-AD; Amendment 
39-21498; AD 2021-08-04]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2013-07-
09, which applied to certain The Boeing Company Model 737-700, -700C, -
800, and -900ER series airplanes, Model 747-400F series airplanes, and 
Model 767-200 and -300 series airplanes. AD 2013-07-09 required a 
general visual inspection for affected serial numbers of the crew 
oxygen mask stowage box units, and replacement or re-identification as 
necessary. This AD retains the requirements of AD 2013-07-09 and 
expands the applicability. This AD was prompted by a determination that 
the affected parts may be installed on airplanes outside the original 
applicability of AD 2013-07-09. The FAA is issuing this AD to address 
the unsafe condition on these products.

DATES: This AD is effective May 26, 2021.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of May 20, 2013 
(78 FR 22178, April 15, 2013).

ADDRESSES: For Boeing service information identified in this final 
rule, contact Boeing Commercial Airplanes, Attention: Contractual & 
Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, 
CA 90740-5600; telephone 562-797-1717; internet <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>. For Intertechnique service information 
identified in this final rule, contact Aerotechnics, 61 rue Pierre 
Curie BP 1, 78373 Plaisir, CEDEX, France; phone: +33 1 6486 6964; 
internet <a href="https://www.zodiacaerospace.com">https://www.zodiacaerospace.com</a>. You may view this service 
information at the FAA, Airworthiness Products Section, Operational 
Safety Branch, 2200 South 216th St., Des Moines, WA. For information on 
the availability of this material at the FAA, call 206-231-3195. It is 
also available on the internet at <a href="https://www.regulations.gov">https://www.regulations.gov</a> by 
searching for and locating Docket No. FAA-2019-0480.

Examining the AD Docket

    You may examine the AD docket on the internet at <a href="https://www.regulations.gov">https://www.regulations.gov</a> by searching for and locating Docket No. FAA-2019-
0480; 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, any comments received, and other information. The 
address for Docket Operations 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: Nicole Tsang, Aerospace Engineer, 
Cabin Safety and Environmental Systems Section, FAA, Seattle ACO 
Branch, 2200 South 216th St., Des Moines, WA 98198; phone and fax: 206-
231-3959; email: <a href="/cdn-cgi/l/email-protection#d896b1bbb7b4bdf68bf68cabb9b6bf98beb9b9f6bfb7ae"><span class="__cf_email__" data-cfemail="eca2858f838089c2bfc2b89f8d828bac8a8d8dc28b839a">[email&#160;protected]</span></a>.

SUPPLEMENTARY INFORMATION: 

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to supersede AD 2013-07-09, Amendment 39-17413 (78 FR 
22178, April 15, 2013) (AD 2013-07-09). AD 2013-07-09 applied to 
certain The Boeing Company Model 737-700, -700C, -800, and -900ER 
series airplanes, Model 747-400F series airplanes, and Model 767-200 
and -300 series airplanes. The NPRM published in the Federal Register 
on June 25, 2019 (84 FR 29818). The NPRM was prompted by reports 
indicating that certain crew oxygen mask stowage box units were 
possibly delivered with a burr in the inlet fitting. The burr might 
break loose during test or operation, and might pose an ignition source 
or cause an inlet valve to jam. The NPRM was also prompted by a 
determination that the affected parts may be installed on airplanes 
outside the original applicability of AD 2013-07-09. The NPRM proposed 
to continue to require a general visual inspection for affected serial 
numbers of the crew oxygen mask stowage box units, and replacement or 
re-identification as necessary. The NPRM also proposed to expand the 
applicability to include those other airplanes. The FAA is issuing this 
AD to address this possible ignition source, which could result in an 
oxygen-fed fire; or an inlet valve jam in a crew oxygen mask stowage 
box unit, which could result in restricted flow of oxygen.
    The FAA issued a supplemental NPRM (SNPRM) that published in the 
Federal Register on November 5, 2020 (85 FR 70526). The SNPRM proposed 
to continue to require a general visual inspection for affected serial 
numbers of the crew oxygen mask stowage box units, and replacement or 
re-identification as necessary. The SNPRM also proposed to expand the 
applicability to include additional airplane models.

Comments

    The FAA gave the public the opportunity to participate in 
developing this AD. The following presents the comments received on the 
SNPRM and the FAA's response to each comment.

Support for the SNPRM

    The Air Line Pilots Association, International (ALPA) and Boeing 
expressed support for the SNPRM. Additional comments from ALPA are 
addressed below.

Effect of Winglets on Accomplishment of the Proposed Actions

    Aviation Partners Boeing stated that the installation of blended or 
split scimitar winglets per Supplemental Type Certificate (STC) 
ST01219SE on Model 737CL airplanes (Model 737-200, -300, -400, and -500 
series airplanes), and blended winglets per STC ST01518SE on Model 757 
airplanes, does not affect the accomplishment of the manufacturer's 
service instructions.
    The FAA agrees with the commenter that STC ST01219SE and STC 
ST01518SE do not affect the accomplishment of the manufacturer's

[[Page 20622]]

service instructions. Therefore, the installation of STC ST01219SE or 
STC ST01518SE does not affect the ability to accomplish the actions 
required by this AD. The FAA has not changed this AD in this regard.

Request To Shorten the Compliance Time

    ALPA requested that the FAA shorten the compliance time of the 
proposed AD from 24 months to 12 months. ALPA noted that several 
commenters on the NPRM requested an extended compliance time, and that 
it is not in favor of an extension.
    The FAA disagrees with the commenter's request. ALPA did not 
provide justification for its request. As noted in the SNPRM, in 
developing an appropriate compliance time for this action, the FAA 
considered the safety implications, parts availability, and normal 
maintenance schedules for the timely accomplishment of the inspection 
and replacement or re-identification as necessary. Further, operators 
are always permitted to accomplish the requirements of an AD at a time 
earlier than the specified compliance time. In addition, to reduce the 
compliance time of the proposed AD would necessitate (under the 
provisions of the Administrative Procedure Act) reissuing the notice, 
reopening the period for public comment, considering additional 
comments subsequently received, and eventually issuing a final rule. 
That procedure could add unwarranted time to the rulemaking process. In 
light of this, and in consideration of the amount of time that has 
already elapsed since issuance of the original notice, the FAA has 
determined that further delay of this AD is not appropriate. The FAA 
has not changed this AD in this regard.

Request To Allow a Records Review Based on Certain Additional Criteria

    United Parcel Service Co. (UPS) requested that the introductory 
text to paragraph (i) of the proposed AD be revised to allow a records 
review in lieu of the specified inspection, provided it can be 
conclusively determined that the serial number is not an affected 
(suspect) part (one that is identified in the Appendix of 
Intertechnique Service Bulletin MXP1/4-35-175, Revision 2, dated May 
10, 2011). UPS noted that paragraph (i) of the proposed AD would allow 
a records review if the serial number of the crew oxygen mask stowage 
box unit could be conclusively determined. UPS noted that it has 
identified scenarios where the serial number may not be conclusively 
known, but the unit can be confirmed to not be one of the affected 
units. UPS explained that Boeing was not consistent in providing serial 
numbers for the units with delivery documents. However, UPS noted that 
through records showing when units were changed, as well as knowing the 
date of production of a given aircraft, UPS can conclusively determine 
that the units with the affected serial numbers were not installed on a 
given aircraft.
    The FAA agrees with the commenter's request for the reasons 
provided. The FAA has revised the introductory text to paragraph (i) of 
this AD to clarify that a records review is also acceptable if it can 
be conclusively determined that the serial number is not one that is 
identified in the Appendix of Intertechnique Service Bulletin MXP1/4-
35-175, Revision 2, dated May 10, 2011.

Request To Revise Manufacturing Date Range

    United Airlines requested that paragraph (i)(1) of the proposed AD 
be revised to specify that units with a manufacturing date outside the 
range of July 2007 through November 2007 inclusive (instead of July 12, 
2007, through November 20, 2007, inclusive) do not need to be replaced. 
United Airlines also requested that similar revisions be made to the 
introductory text to paragraph (i) of the proposed AD, and paragraphs 
(i)(2), (j)(1), and (j)(2) of the proposed AD. United Airlines stated 
that the manufacture date on the mask stowage box units typically shows 
only the month and year (in MMYYYY format). The commenter noted that 
determining the exact calendar date of manufacture may not be possible, 
and without a specific serial number, the manufacturer would not be 
able to narrow down the date.
    The FAA partially agrees with the commenter's request. The FAA 
agrees that determining the exact date of manufacture may not be 
possible because the manufacturer date on the mask stowage box units 
typically shows only the month and year. The FAA has therefore revised 
paragraph (i)(1) of this AD to specify that units with a manufacturing 
date outside the range of July 2007 through November 2007 inclusive do 
not need to be replaced. The FAA has also revised paragraph (j)(1) of 
this AD to specify that units where the serial number is unreadable or 
undetermined, but the manufacturing date can conclusively be determined 
to be outside the range of July 2007 through November 2007 inclusive, 
may be installed on an airplane. However, the FAA has determined that 
the commenter's suggested revisions to the introductory text to 
paragraph (i) of this AD are not needed because the introductory text 
to paragraph (i) of this AD only requires determining the serial number 
and does not specify actions based on whether or not the serial number 
can be determined. In addition, the FAA has determined that the 
commenter's suggested revisions to paragraphs (i)(2) and (j)(2) of this 
AD are not needed because the actions in those paragraphs are only 
applicable for units with a known serial number that is identified in 
table 2 of the Appendix of Intertechnique Service Bulletin MXP1/4-35-
175, Revision 2, dated May 10, 2011 (those that need re-
identification).

Request To Allow Use of Aircraft Maintenance Manual (AMM)

    Delta Air Lines (Delta) requested confirmation that it may use the 
respective fleet's AMM to perform removals and installations if any of 
the affected units are found on its airplanes. Delta noted that 
paragraph (i) of the proposed AD does not specify instructions for 
removal or replacement. Delta asked for confirmation that using the 
applicable AMM for these tasks would not require it to obtain an 
alternative method of compliance (AMOC).
    The FAA agrees that the commenter's intended approach is acceptable 
for compliance with this AD and that no AMOC is needed to use the 
applicable AMM. The AMMs for the affected airplanes contain adequate 
instructions for removal and installation of the affected units. No 
change to this AD is necessary.

Clarification of Certain Actions

    The FAA has revised paragraph (i)(1) of this AD to clarify 
conditions that require replacement of a crew oxygen mask stowage box 
unit, which includes an unreadable or undetermined serial number, 
except as otherwise specified.
    The FAA has also revised paragraph (j)(1) of this AD to clarify 
conditions that prohibit the installation of a crew oxygen mask stowage 
box unit, which includes an unreadable or undetermined serial number, 
except as specified otherwise.

Conclusion

    The FAA reviewed the relevant data, considered the comments 
received, and determined that air safety and the public interest 
require adopting this AD with the changes described previously, and 
minor editorial changes. The FAA has determined that these minor 
changes:

[[Page 20623]]

    <bullet> Are consistent with the intent that was proposed in the 
SNPRM for addressing the unsafe condition; and
    <bullet> Do not add any additional burden upon the public than was 
already proposed in the SNPRM.
    The FAA also determined that these changes will not increase the 
economic burden on any operator or increase the scope of this AD.

Related Service Information Under 1 CFR Part 51

    This AD requires Boeing Alert Service Bulletin 737-35A1121, 
Revision 1, dated November 7, 2011; Boeing Alert Service Bulletin 747-
35A2126, Revision 1, dated September 29, 2011; Boeing Alert Service 
Bulletin 767-35A0057, Revision 1, dated November 17, 2011; and 
Intertechnique Service Bulletin MXP1/4-35-175, Revision 2, dated May 
10, 2011; which the Director of the Federal Register approved for 
incorporation by reference as of May 20, 2013 (78 FR 22178, April 15, 
2013). 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

    The FAA estimates that this AD affects 3,723 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Inspection (retained action from AD     1 work-hour x $85 per                 $0             $85          $3,400
 2013[dash]07[dash]09) (40 airplanes).   hour = $85.
Inspection (new action) (3,683          1 work-hour x $85 per                  0              85         313,055
 airplanes).                             hour = $85.
----------------------------------------------------------------------------------------------------------------

    The FAA has received no definitive data that would enable providing 
cost estimates for the on-condition actions specified in this AD.

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.
    The FAA is 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 rulemaking action.

Regulatory Findings

    The FAA has determined that 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 that this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Will not affect intrastate aviation in Alaska, and
    (3) 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 
reference, Safety.

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

0
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]

0
2. The FAA amends Sec.  39.13 by
0
a. Removing Airworthiness Directive (AD) 2013-07-09, Amendment 39-17413 
(78 FR 22178, April 15, 2013); and
0
b. Adding the following new AD:

2021-08-04 The Boeing Company: Amendment 39-21498; Docket No. FAA-
2019-0480; Product Identifier 2019-NM-041-AD.

(a) Effective Date

    This airworthiness directive (AD) is effective May 26, 2021.

(b) Affected ADs

    This AD replaces AD 2013-07-09, Amendment 39-17413 (78 FR 22178, 
April 15, 2013) (AD 2013-07-09).

(c) Applicability

    This AD applies to all The Boeing Company airplanes, 
certificated in any category, as identified in paragraphs (c)(1) 
through (5) of this AD.
    (1) Model 737-200, -300, -400, -500, -600, -700, -700C, -800, -
900, and -900ER series airplanes.
    (2) Model 737-8 and 737-9 airplanes.
    (3) Model 747-200B, 747-200C, 747-200F, 747-400, 747-400D, and 
747-400F series airplanes.
    (4) Model 757-200, -200PF, -200CB, and -300 series airplanes.
    (5) Model 767-200, -300, -300F, and -400ER series airplanes.

(d) Subject

    Air Transport Association (ATA) of America Code 35, Oxygen.

(e) Unsafe Condition

    This AD was prompted by reports indicating that certain crew 
oxygen mask stowage box units were possibly delivered with a burr in 
the inlet fitting. The burr might break loose during test or 
operation, and might pose an ignition source or cause an inlet valve 
to jam. This AD was also prompted by a determination that the 
affected parts may be installed on airplanes outside the 
applicability of AD 2013-07-09. The FAA is issuing this AD to 
address this possible ignition source, which could result in an 
oxygen-fed fire; or an inlet valve jam in a crew oxygen mask stowage 
box unit, which could result in restricted flow of oxygen.

(f) Compliance

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

(g) Retained Inspection and Corrective Action, With No Changes

    This paragraph restates the requirements of paragraph (g) of AD 
2013-07-09 with no changes. For The Boeing Company Model 737 
airplanes as identified in Boeing Alert

[[Page 20624]]

Service Bulletin 737-35A1121, Revision 1, dated November 7, 2011; 
The Boeing Company Model 747 airplanes as identified in Boeing Alert 
Service Bulletin 747-35A2126, Revision 1, dated September 29, 2011; 
and The Boeing Company Model 767 airplanes as identified in Boeing 
Alert Service Bulletin 767-35A0057, Revision 1, dated November 17, 
2011: Within 24 months after May 20, 2013 (the effective date of AD 
2013-07-09), do a general visual inspection to determine if the 
serial number of the crew oxygen mask stowage box unit is identified 
in the Appendix of Intertechnique Service Bulletin MXP1/4-35-175, 
Revision 2, dated May 10, 2011, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 737-
35A1121, Revision 1, dated November 7, 2011; Boeing Alert Service 
Bulletin 747-35A2126, Revision 1, dated September 29, 2011; or 
Boeing Alert Service Bulletin 767-35A0057, Revision 1, dated 
November 17, 2011; as applicable. A review of airplane maintenance 
records is acceptable in lieu of this inspection if the serial 
number of the crew oxygen mask stowage box unit can be conclusively 
determined from that review.
    (1) If any crew oxygen mask stowage box unit has a serial number 
identified in table 1 of the Appendix of Intertechnique Service 
Bulletin MXP1/4-35-175, Revision 2, dated May 10, 2011: Before 
further flight, replace the crew oxygen mask stowage box unit with a 
new or serviceable unit in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin 737-35A1121, Revision 
1, dated November 7, 2011; Boeing Alert Service Bulletin 747-
35A2126, Revision 1, dated September 29, 2011; or Boeing Alert 
Service Bulletin 767-35A0057, Revision 1, dated November 17, 2011; 
as applicable.
    (2) If any crew oxygen mask stowage box unit has a serial number 
identified in table 2 of the Appendix of Intertechnique Service 
Bulletin MXP1/4-35-175, Revision 2, dated May 10, 2011: Before 
further flight, add the letter ``I'' to the end of the serial number 
(identified as ``SER'') on the identification label, in accordance 
with the Accomplishment Instructions of Intertechnique Service 
Bulletin MXP1/4-35-175, Revision 2, dated May 10, 2011; and 
reinstall in accordance with the Accomplishment Instructions of 
Boeing Alert Service Bulletin 737-35A1121, Revision 1, dated 
November 7, 2011; Boeing Alert Service Bulletin 747-35A2126, 
Revision 1, dated September 29, 2011; or Boeing Alert Service 
Bulletin 767-35A0057, Revision 1, dated November 17, 2011; as 
applicable.
    (3) If no crew oxygen mask stowage box unit has a serial number 
identified in the Appendix of Intertechnique Service Bulletin MXP1/
4-35-175, Revision 2, dated May 10, 2011: Unless a records review 
was done to determine the serial number, before further flight, 
reinstall the crew oxygen mask stowage box unit, in accordance with 
the Accomplishment Instructions of Boeing Alert Service Bulletin 
737-35A1121, Revision 1, dated November 7, 2011; Boeing Alert 
Service Bulletin 747-35A2126, Revision 1, dated September 29, 2011; 
or Boeing Alert Service Bulletin 767-35A0057, Revision 1, dated 
November 17, 2011; as applicable.

(h) Retained Parts Installation Prohibition, With No Changes

    This paragraph restates the requirements of paragraph (h) of AD 
2013-07-09 with no changes. For airplanes identified in paragraph 
(g) of this AD: As of May 20, 2013 (the effective date of AD 2013-
07-09), no person may install a crew oxygen mask stowage box unit 
with a serial number listed in the Appendix of Intertechnique 
Service Bulletin MXP1/4-35-175, Revision 2, dated May 10, 2011, on 
any airplane.

(i) New Inspection and Corrective Action

    For airplanes other than those identified in paragraph (g) of 
this AD: Within 24 months after the effective date of this AD, do a 
general visual inspection to determine if the serial number of the 
crew oxygen mask stowage box unit is identified in the Appendix of 
Intertechnique Service Bulletin MXP1/4-35-175, Revision 2, dated May 
10, 2011. A review of airplane maintenance records is acceptable in 
lieu of this inspection if the serial number of the crew oxygen mask 
stowage box unit can be conclusively determined from that review, or 
if it can be conclusively determined that the serial number is not 
one that is identified in the Appendix of Intertechnique Service 
Bulletin MXP1/4-35-175, Revision 2, dated May 10, 2011.
    (1) If any crew oxygen mask stowage box unit has a serial number 
identified in table 1 of the Appendix of Intertechnique Service 
Bulletin MXP1/4-35-175, Revision 2, dated May 10, 2011, or the crew 
oxygen mask stowage box unit has a serial number that is unreadable 
or undetermined: Before further flight, replace the crew oxygen mask 
stowage box unit with a new or serviceable unit. If any crew oxygen 
mask stowage box unit's serial number is unreadable or undetermined, 
but the manufacturing date can conclusively be determined to be 
outside the range of July 2007 through November 2007 inclusive, the 
crew oxygen mask stowage box unit does not need to be replaced.
    (2) If any crew oxygen mask stowage box unit has a serial number 
identified in table 2 of the Appendix of Intertechnique Service 
Bulletin MXP1/4-35-175, Revision 2, dated May 10, 2011: Before 
further flight, add the letter ``I'' to the end of the serial number 
(identified as ``SER'') on the identification label, in accordance 
with the Accomplishment Instructions of Intertechnique Service 
Bulletin MXP1/4-35-175, Revision 2, dated May 10, 2011; and 
reinstall the crew oxygen mask stowage box unit.

(j) New Parts Installation Prohibition

    (1) For airplanes other than those identified in paragraph (g) 
of this AD: As of the effective date of this AD, no person may 
install a crew oxygen mask stowage box unit with a serial number 
identified in table 1 of the Appendix of Intertechnique Service 
Bulletin MXP1/4-35-175, Revision 2, dated May 10, 2011; or any crew 
oxygen mask stowage box unit with a serial number that is unreadable 
or undetermined unless the manufacturing date can conclusively be 
determined by a review of the airplane maintenance records to be 
outside the range of July 2007 through November 2007 inclusive.
    (2) For airplanes other than those identified in paragraph (g) 
of this AD: As of the effective date of this AD, no person may 
install a crew oxygen mask stowage box unit with a serial number 
identified in table 2 of the Appendix of Intertechnique Service 
Bulletin MXP1/4-35-175, Revision 2, dated May 10, 2011, on any 
airplane, unless that crew oxygen mask stowage box unit has been 
modified as required by paragraph (i)(2) of this AD.

(k) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle ACO Branch, FAA, has the authority to 
approve AMOCs for this AD, if requested using the procedures found 
in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request 
to your principal inspector or local Flight Standards Office, as 
appropriate. If sending information directly to the manager of the 
certification office, send it to the attention of the person 
identified in paragraph (l) of this AD. Information may be emailed 
to: <a href="/cdn-cgi/l/email-protection#fdc4d0bcb3b0d0ae989c89899198d0bcbeb2d0bcb0b2bed0af988c88988e898ebd9b9c9cd39a928b"><span class="__cf_email__" data-cfemail="6f56422e2122423c0a0e1b1b030a422e2c20422e22202c423d0a1e1a0a1c1b1c2f090e0e41080019">[email&#160;protected]</span></a>.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the responsible Flight Standards Office.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair, modification, or alteration required by this AD 
if it is approved by the Boeing Company Organization Designation 
Authorization (ODA) that has been authorized by the Manager, Seattle 
ACO Branch, FAA, to make those findings. To be approved, the repair 
method, modification deviation, or alteration deviation must meet 
the certification basis of the airplane, and the approval must 
specifically refer to this AD.
    (4) AMOCs approved previously for AD 2013-07-09 are approved as 
AMOCs for the corresponding provisions of this AD.

(l) Related Information

    For more information about this AD, contact Nicole Tsang, 
Aerospace Engineer, Cabin Safety and Environmental Systems Section, 
FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 98198; 
phone and fax: 206-231-3959; email: <a href="/cdn-cgi/l/email-protection#fcb2959f939099d2afd2a88f9d929bbc9a9d9dd29b938a"><span class="__cf_email__" data-cfemail="753b1c161a19105b265b2106141b12351314145b121a03">[email&#160;protected]</span></a>.

(m) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless this AD specifies otherwise.
    (3) The following service information was approved for IBR on 
May 20, 2013 (78 FR 22178, April 15, 2013).
    (i) Boeing Alert Service Bulletin 737-35A1121, Revision 1, dated 
November 7, 2011.
    (ii) Boeing Alert Service Bulletin 747-35A2126, Revision 1, 
dated September 29, 2011.

[[Page 20625]]

    (iii) Boeing Alert Service Bulletin 767-35A0057, Revision 1, 
dated November 17, 2011.
    (iv) Intertechnique Service Bulletin MXP1/4-35-175, Revision 2, 
dated May 10, 2011.
    (4) For Boeing service information identified in this AD, 
contact Boeing Commercial Airplanes, Attention: Contractual & Data 
Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 
90740-5600; telephone 562-797-1717; internet <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
    (5) For Intertechnique service information identified in this 
AD, contact Aerotechnics, 61 rue Pierre Curie BP 1, 78373 Plaisir, 
CEDEX, France; phone: +33 1 6486 6964; internet <a href="https://www.zodiacaerospace.com">https://www.zodiacaerospace.com</a>.
    (6) You may view this service information at the FAA, 
Airworthiness Products Section, Operational Safety Branch, 2200 
South 216th St., Des Moines, WA. For information on the availability 
of this material at the FAA, call 206-231-3195.
    (7) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, email <a href="/cdn-cgi/l/email-protection#dbbdbebfa9bebcf5b7bebcbab79bb5baa9baf5bcb4ad"><span class="__cf_email__" data-cfemail="2f494a4b5d4a4801434a484e436f414e5d4e01484059">[email&#160;protected]</span></a>, or go to: <a href="https://www.archives.gov/federal-register/cfr/ibr-locations.html">https://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.

    Issued on March 30, 2021.
Ross Landes,
Deputy Director for Regulatory Operations, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2021-08213 Filed 4-20-21; 8:45 am]
BILLING CODE 4910-13-P