## 22175 Federal Register / Vol. 78, No. 72 / Monday, April 15, 2013 / Rules and Regulations

dated April 10, 2003; or Boeing Service Bulletin 757–57–0060, dated January 9, 2003.

(2) For all airplanes, as identified in Boeing Service Bulletin 757–57–0060, Revision 4, dated December 7, 2012: Boeing Service Bulletin 757–57–0060, Revision 2, dated May 24, 2007; or Boeing Service Bulletin 757–57– 0060, Revision 3, dated May 9, 2012.

(3) For all airplanes, as identified in Boeing Service Bulletin 757–57–0061, Revision 3, dated December 7, 2012: Boeing Service Bulletin 757–57–0061, Revision 1, dated May 24, 2007; or Boeing Service Bulletin 757–57– 0061, Revision 2, dated May 4, 2012.

(4) For Group 2 airplanes, as identified in Boeing Service Bulletin 757–57–0061, Revision 3, dated December 7, 2012: Boeing Service Bulletin 757–57–0061, dated February 6, 2003.

(l) No Reporting Requirement

Although Boeing Service Bulletin 757–57– 0060, Revision 4, dated December 7, 2012; and Boeing Service Bulletin 757–57–0061, Revision 3, dated December 7, 2012; specify to submit certain information to the manufacturer, this AD does not include that requirement.
(m) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Seattle Aircraft Certification Office (ACO), 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 District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in the Related Information section of this AD. Information may be emailed to: -ANMSeattle-ACO-AMOC-REQUESTS@faa.gov.

(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/ certificate holding district office.

(n) Related Information

(1) For more information about this AD, contact Kevin Nguyen, Aerospace Engineer, Propulsion Branch, ANM–140S, FAA, Seattle Aircraft Certification Office (ACO), 1601 Lind Avenue SW., Renton, WA 98057–3356; phone: (425) 917–6501; fax: (425) 917–6590; email: kevin.nguyen@faa.gov.

(2) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H–65, Seattle, Washington 98124–2207; telephone 206–544–5000, extension 1; fax 206–766– 5680; Internet https:// www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425–227–1221.
(o) 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 the AD specifies otherwise.

(i) Boeing Service Bulletin 757–57–0060, Revision 4, dated December 7, 2012.

(ii) Boeing Service Bulletin 757–57–0061, Revision 3, dated December 7, 2012.

(3) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H–65, Seattle, Washington 98124–2207; telephone 206–544–5000, extension 1; fax 206–766– 5680; Internet https:// www.myboeingfleet.com.

(4) You may view this service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425–227–1221.

(5) You may view copies of 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, call 202–741–6030, or go to: http://www.archives.gov/federal-register/cfr/ibrlocations.html.

Issued in Renton, Washington, on March
29, 2013. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service.

[FR Doc. 2013–08191 Filed 4–12–13; 8:45 am]

**BILLING CODE 4910–13–P**



### DEPARTMENT OF TRANSPORTATION

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2012–1036; Directorate Identifier 2011–NM–122–AD; Amendment**  **39–17408; AD 2013–07–04]**

**RIN 2120–AA64**



### Airworthiness Directives; Airbus **Airplanes**

**AGENCY** 

### : Federal Aviation Administration (FAA), Department of Transportation (DOT).

**ACTION** 

### : Final rule.

**SUMMARY** 

### : We are superseding an existing airworthiness directive (AD) for certain Airbus Model A319, A320, and A321 series airplanes. That AD currently requires installing spacer assemblies at the attachment points of the YZ-latches of the cargo loading system (CLS) in the forward and aft cargo compartments, as applicable. This new AD also requires modifying the attachment points of fixed YZ-latches of the CLS lower deck cargo holds on those airplanes on which one or both lower deck cargo holds have not been modified, which terminates the existing requirements. This AD was prompted by results from tests that have shown that the attachment points of the YZ-latches of the cargo loading system (CLS) fail under maximum loads and reports that installation has been applied only on one of the lower deck cargo holds, instead of on both forward and aft cargo holds, and that some airplanes could have installed the affected YZ-latches through the instructions of the cargo conversion manual. We are issuing this AD to prevent failure of the attachment points of the YZ-latches, which could result in unrestrained cargo causing damage to the fire protection system, hydraulic system, electrical wiring, or other equipment located in the forward and aft cargo compartments. This damage could adversely affect the continued safe flight of the airplane.

**DATES** 

### : This AD becomes effective May
20, 2013.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of May 20, 2013.

The Director of the Federal Register approved the incorporation by reference of a certain other publication listed in this AD as of April 12, 2007 (72 FR 10348, March 8, 2007).

**ADDRESSES** 

### : You may examine the AD docket on the Internet at http:// www.regulations.gov or in person at the U.S. Department of Transportation, Docket Operations, M–30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE., Washington, DC.

**FOR FURTHER INFORMATION CONTACT**

### : Sanjay Ralhan, Aerospace Engineer, International Branch, ANM–116, Transport Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton, WA 98057–3356; telephone (425) 227–1405; fax (425) 227–1149.

**SUPPLEMENTARY INFORMATION** 

### :

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to the specified products. That NPRM was published in the Federal Register on October 4, 2012 (77 FR 60653), and proposed to supersede AD 2007–05–13, Amendment 39–14974 (72 FR 10348, March 8, 2007). That NPRM proposed to correct an unsafe condition for the specified products. The Mandatory Continuing Airworthiness Information (MCAI) states:

Investigation has revealed that the installed Tie Down Points of YZ latches on the Cargo Loading System (CLS) of Airbus A319, A320 and A321 aeroplanes do not withstand the


## 22176 Federal Register / Vol. 78, No. 72 / Monday, April 15, 2013 / Rules and Regulations

maximum loads in accordance with the certification requirements (CS 25.787 ‘‘Stowage compartments’’).

In case of failure of Tie Down Points, unrestrained cargo parts could cause damage in the Forward (FWD) and AFT lower deck cargo holds (e.g. air conditioning, fire protection system, hydraulic system, electrical wiring, etc.), and therefore could have an impact on the safety of the flight.

EASA AD 2006–0184 [ which corresponds to FAA AD 2007–05–13, Amendment 39– 14974 (72 FR 10348, March 8, 2007)] was issued to require the modification of the attachment points of fixed YZ latches of the CLS in both FWD and AFT lower deck cargo holds, as applicable to aeroplane configuration, in accordance with Airbus SB
A320–25–1294 Revision 01.

It has recently been identified that for some aeroplanes, Airbus SB A320–25–1294 Revision 01 has been applied only on one of the lower deck cargo holds (FWD or AFT) while both cargo compartments were concerned by the modification, and that some aeroplanes could have installed the affected YZ [latches] through the instructions of the Cargo Conversion Manual.

For the reasons described above, this [EASA] AD, which supersedes EASA AD 2006–0184, requires modification of the attachment points of fixed YZ latches of the CLS lower deck cargo holds on those aeroplanes on which one or both lower deck cargo holds have not been modified.

This [EASA] AD also prohibits installation of the affected YZ latches, identified by Part Number (P/N) in Table 1 of Appendix 1 of this [EASA] AD, on any aeroplane as replacement parts, unless all the attachment points of the YZ latch have been modified.



### You may obtain further information by examining the MCAI in the AD docket.

Comments

We gave the public the opportunity to participate in developing this AD. We considered the comments received.
Request To Clarify Terminating Action

Airbus requested that we clarify the paragraph identifier specified in the last sentence of paragraph (g) of the NPRM (77 FR 60653, October 4, 2012). Airbus suggested that the correct identifier should be paragraph (h) instead of paragraph (i) of the NPRM.

We agree with the commenter and have revised paragraph (g) of this AD accordingly.
Request To Revise Airbus Contact Information

Airbus requested that we revise the contact information reference to the Airbus office of airworthiness from
EAW to EIAS.

We agree and have revised the contact information specified in paragraph (l)(2) of this AD. Additional Change Made to This AD We have removed table 1 to paragraph (h) from this AD. Instead, we have listed the subject part numbers in paragraphs (h)(1) through (h)(7) of this AD. This change does not affect the intent of that paragraph.

Conclusion

We reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD with the changes described previously— and minor editorial changes. We have determined that these changes:

• Are consistent with the intent that was proposed in the NPRM (77 FR 60653, October 4, 2012) for correcting the unsafe condition; and

• Do not add any additional burden upon the public than was already proposed in the NPRM (77 FR 60653, October 4, 2012).
Costs of Compliance

We estimate that this AD will affect about 740 products of U.S. registry.

The actions that are required by AD 2007–05–13, Amendment 39–14974 (72 FR 10348, March 8, 2007), and retained in this AD take about 4 work-hours per product, at an average labor rate of $85 per work-hour. Required parts cost about $2,049 per product. Based on these figures, the estimated cost of the currently required actions is $2,389 per product.

We estimate that it will take about 15 work-hours per product to comply with the new basic requirements of this AD.The average labor rate is $85 per workhour. Required parts will cost up to $2,656 per product. Where the service information lists required parts costs that are covered under warranty, we have assumed that there will be no charge for these parts. As we do not control warranty coverage for affected parties, some parties may incur costs higher than estimated here. Based on these figures, we estimate the cost of this AD to the U.S. operators to be up to $2,908,940, or $3,931 per product.
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 rulemaking
action.
Regulatory Findings

We 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. 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.

We prepared a regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket.

Examining the AD Docket

You may examine the AD docket on the Internet at http:// www.regulations.gov; or in person at the Docket Operations office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains the NPRM (77 FR 60653, October 4, 2012), the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone (800) 647–5527) is in the **ADDRESSES** 

### section. Comments will be available in the AD docket shortly after receipt.

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:


## 22177 Federal Register / Vol. 78, No. 72 / Monday, April 15, 2013 / Rules and Regulations

**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.

**§ 39.13 [Amended]**

■ 

### 2. The FAA amends § 39.13 by removing airworthiness directive (AD) 2007–05–13, Amendment 39–14974 (72 FR 10348, March 8, 2007), and adding the following new AD:

2013–07–04 Airbus: Amendment 39–17408. Docket No. FAA–2012–1036; Directorate Identifier 2011–NM–122–AD.

(a) Effective Date

This airworthiness directive (AD) becomes effective May 20, 2013.

(b) Affected ADs

This AD supersedes AD 2007–05–13, Amendment 39–14974 (72 FR 10348, March 8, 2007).
(c) Applicability

This AD applies to Airbus Model A319– 111, –112, –113, –114, –115, –131, –132, and –133 airplanes; Model A320–111, –211, –212, –214, –231, –232, and –233 airplanes; and Model A321–111, –112, –131, –211, –212, –213, –231, and –232 airplanes; certificated in any category; all manufacturer serial numbers.
(d) Subject

Air Transport Association (ATA) of America Code 25, Equipment/Furnishings.

(e) Reason

This AD was prompted by results from tests that have shown that the attachment points of the YZ-latches of the cargo loading system (CLS) fail under maximum loads and reports that installation has been applied only on one of the lower deck cargo holds, instead of on both forward and aft cargo holds, and that some airplanes could have installed the affected YZ-latches through the instructions of the cargo conversion manual. We are issuing this AD to prevent failure of the attachment points of the YZ-latches, which could result in unrestrained cargo causing damage to the fire protection system, hydraulic system, electrical wiring, or other equipment located in the forward and aft cargo compartments. This damage could adversely affect the continued safe flight of the airplane.
(f) Compliance

You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
(g) Retained Spacer Assembly Installation

This paragraph restates the requirements of paragraph (f) of AD 2007–05–13, Amendment 39–14974 (72 FR 10348, March 8, 2007). For Airbus Model A319, A320, and A321 series airplanes identified in paragraphs (g)(1) and (g)(2) of this AD: Within 36 months after April 12, 2007 (the effective date of AD 2007–05–13), install spacer assemblies at the attachment points of the YZ-latches of the CLS in the forward and aft cargo compartments, as applicable, in accordance with the Accomplishment Instructions of Airbus Service Bulletin A320–25–1294, Revision 02, dated September 5, 2006. Accomplishing the actions in paragraph (h) of this AD terminates the requirements of paragraph (g) of this AD.

(1) Airplanes on which one of the following has been incorporated in production: Airbus Modification 20065,
20040, 24495, 24848, 24496, 21895, 21896, 25905, 25907, 22601, 22602, 27187, 28319, 28322, 28330, 28335, or 31797.

(2) Airplanes on which one of the following has been incorporated in service: Airbus Service Bulletin A320–25–1132, A320–25–1133, A320–25–1145, A320–25– 1175, A320–25–1177, A320–25–1276, A320– 25–1278, A320–28–1134, or A320–28–1141.

(h) New Modification

Except for Model A319, A320, and A321 series airplanes on which both Airbus Modifications 32244 and 32245, or both Airbus Modifications 32316 and 32317, have been incorporated in production, and on which no YZ-latch replacements have been made since first flight: Within 20 months after the effective date of this AD, modify the attachment points of fixed YZ-latches of the CLS, having a part number (P/N) listed in paragraphs (h)(1) through (h)(7) of this AD, in both forward and aft lower deck cargo holds by adding spacer assemblies having P/ N D2557232700000, in accordance with the Accomplishment Instructions of Airbus Mandatory Service Bulletin A320–25–1294, Revision 06, dated July 23, 2010. Accomplishing the actions specified in paragraph (h) of this AD terminates the requirements of paragraph (g) of this AD.

(1) P/N D 255 7 2380 000. (2) P/N D 255 7 2380 002. (3) P/N D 255 7 2380 006. (4) P/N D 255 7 2380 008. (5) P/N D 255 7 2350 002. (6) P/N D 255 7 2350 004. (7) P/N D 255 7 2350 006.

(i) Parts Installation Limitation

As of the effective date of this AD, no person may install, on the CLS of any airplane, a YZ-latch having a part number listed in paragraphs (h)(1) through paragraph (h)(7) of this AD, unless it has been modified in accordance with the requirements of paragraph (h) of this AD.
(j) Credit for Previous Actions

(1) This paragraph provides credit for the installation required by paragraph (g) of this AD, if the installation was performed before April 12, 2007 (the effective date of AD 2007–05–13, Amendment 39–14974 (72 FR 10348, March 8, 2007), using Airbus Service Bulletin A320–25–1294, dated March 14, 2003; or Revision 01, dated March 27, 2006. Neither service bulletin is incorporated by reference in this AD.

(2) This paragraph provides credit for the modification required by paragraph (h) of this AD, if the modification was performed before the effective date of this AD using any of the following service information, and the additional work is done in accordance with the applicable instructions referenced as ‘‘ADDITIONAL WORK’’ in the Accomplishment Instructions of Airbus Mandatory Service Bulletin A320–25–1294, Revision 06, dated July 23, 2010.

(i) Airbus Service Bulletin A320–25–1294, dated March 14, 2003.

(ii) Airbus Service Bulletin A320–25–1294, Revision 01, dated March 27, 2006.

(iii) Airbus Service Bulletin A320–25– 1294, Revision 02, dated September 5, 2006.

(iv) Airbus Mandatory Service Bulletin A320–25–1294, Revision 03, dated January
22, 2007.

(v) Airbus Mandatory Service Bulletin A320–25–1294, Revision 04, dated March 13,

2008.

(vi) Airbus Mandatory Service Bulletin A320–25–1294, Revision 05, dated January
22, 2009.

(k) Other FAA AD Provisions

The following provisions also apply to this
AD:

(1) Alternative Methods of Compliance (AMOCs): The Manager, International Branch, ANM–116, Transport Airplane Directorate, 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 District Office, as appropriate. If sending information directly to the International Branch, send it to ATTN: Sanjay Ralhan, Aerospace Engineer, International Branch, ANM–116, Transport Airplane Directorate, FAA, 1601 Lind Avenue SW., Renton, WA 98057–3356; telephone (425) 227–1405; fax (425) 227– 1149. Information may be emailed to: 9– ANM–116–AMOC–REQUESTS@faa.gov. Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/ certificate holding district office. The AMOC approval letter must specifically reference this AD.

(2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service.

(l) Related Information

(1) Refer to MCAI European Aviation Safety Agency AD 2011–0077, dated May 5, 2011; and the following service information; for related information.

(i) Airbus Mandatory Service Bulletin A320–25–1294, Revision 06, dated July 23,

2010.

(ii) Airbus Service Bulletin A320–25–1294, Revision 02, dated September 5, 2006.

(2) For service information identified in this AD, contact Airbus SAS—EIAS (Airworthiness Office), 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France; telephone +33 5 61 93 36 96; fax +33 5 61 93 44 51; email account.airworthVerDate Mar<15>2010 16:10 Apr 12, 2013 Jkt 229001 PO 00000 Frm 00027 Fmt 4700 Sfmt 4700 E:\FR\FM\15APR1.SGM 15APR1mstockstill on DSK4VPTVN1PROD with RULES

## 22178 Federal Register / Vol. 78, No. 72 / Monday, April 15, 2013 / Rules and Regulations

eas@airbus.com ; Internet http:// www.airbus.com

. (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 the AD specifies otherwise.

(3) The following service information was approved for IBR on May 20, 2013.

(i) Airbus Mandatory Service Bulletin A320–25–1294, Revision 06, dated July 23,

2010.

(ii) Reserved. (4) The following service information was approved for IBR on of April 12, 2007 (72 FR 10348, March 8, 2007).

(i) Airbus Service Bulletin A320–25–1294, Revision 02, dated September 5, 2006.

(ii) Reserved. (5) For service information identified in this AD, contact Airbus SAS—EIAS (Airworthiness Office), 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France; telephone +33 5 61 93 36 96; fax +33 5 61 93 44 51; email account.airwortheas@airbus.com ; Internet http:// www.airbus.com

.

(6) You may review copies of the service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425–227–1221.

(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, call 202–741–6030, or go to: http://www.archives.gov/federal-register/cfr/ibrlocations.html.

Issued in Renton, Washington, on March
28, 2013. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service.

[FR Doc. 2013–08570 Filed 4–12–13; 8:45 am]

**BILLING CODE 4910–13–P**



### DEPARTMENT OF TRANSPORTATION

**Federal Aviation Administration**

**14 CFR Part 39**

**[Docket No. FAA–2010–1042; Directorate Identifier 2010–NM–094–AD; Amendment**  **39–17413; AD 2013–07–09]**

**RIN 2120–AA64**



### Airworthiness Directives; The Boeing **Company Airplanes**

**AGENCY** 

### : Federal Aviation Administration (FAA), DOT.

**ACTION** 

### : Final rule.

**SUMMARY** 

### : We are adopting a new airworthiness directive (AD) for 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. 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 final rule adds a step to identify and label certain crew oxygen mask stowage box units that have already been inspected and reworked by the supplier, and allows operators to install new or serviceable crew oxygen mask stowage box units, and requires a general visual inspection for affected serial numbers of the crew oxygen mask stowage box units, and replacement or re-identification as necessary. We are issuing this AD to prevent an 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.

**DATES** 

### : This AD is effective May 20,

2013.

The Director of the Federal Register approved the incorporation by reference of certain publications listed in the AD as of May 20, 2013.

**ADDRESSES** 

### : For Boeing service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H–65, Seattle, WA 98124–2207; telephone 206–544–5000, extension 1; fax 206–766–5680; Internet https://www.myboeingfleet.com. For Intertechnique service information identified in this AD, contact Zodiac, 2,rue Maurice Mallet—92137 Issy-lesMoulineaux Cedex France; telephone +33 1 41 23 23 23; fax +33 1 46 48 83 87; Internet http://www.zodiac.com

. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425–227–1221.
Examining the AD Docket

You may examine the AD docket on the Internet at http:// www.regulations.gov; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD, the regulatory evaluation, any comments received, and other information. The address for the Docket Office (phone: 800–647–5527) is Document Management Facility, 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**

### : Susan L. Monroe, Aerospace Engineer, Cabin Safety and Environmental Systems Branch, ANM–150S, FAA, Seattle Aircraft Certification Office (ACO), 1601 Lind Avenue SW., Renton, Washington 98057–3356; phone: 425– 917–6457; fax: 425–917–6590; email: susan.l.monroe@faa.gov

.
**SUPPLEMENTARY INFORMATION** 

### :

Discussion

We issued a supplemental notice of proposed rulemaking (SNPRM) to amend 14 CFR part 39 to include an airworthiness directive (AD) that would apply to the specified products. That SNPRM published in the Federal Register on September 7, 2012 (77 FR 55159). The original NPRM (75 FR 67637, November 3, 2010) proposed to require an inspection for affected serial numbers of the crew oxygen mask stowage box units; and replacement of the crew oxygen mask stowage box unit with a new crew oxygen mask stowage box unit, if necessary. The SNPRM proposed to revise the NPRM by adding a step to identify and label certain crew oxygen mask stowage box units that have already been inspected and reworked by the supplier, and allowing operators to install new or serviceable crew oxygen mask stowage box units.

Comments

We gave the public the opportunity to participate in developing this AD. The following presents the comments received on the proposal (77 FR 55159, September 7, 2012) and the FAA’s response to each comment.
Support for the SNPRM (77 FR 55159, September 7, 2012)

Boeing stated that it supports the SNPRM (77 FR 55159, September 7, 2012).
Request for Clarification of Determination of the Affected Units

American Airlines (AA) requested that we revise the SNPRM (77 FR 55159, September 7, 2012) to clarify the method used by the manufacturer to determine the affected units, and the potential that those units could have been inadvertently installed on other airplanes. AA explained that Boeing Alert Service Bulletin 737–35A1121, dated December 14, 2009, provides limited background information as to how Boeing determined which aircraft