Airworthiness Directives; Boeing Model 737-300, -400, and -500 Series Airplanes, 71830-71832 [E7-24521]

Download as PDF 71830 Federal Register / Vol. 72, No. 243 / Wednesday, December 19, 2007 / Proposed Rules 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. (3) Reporting Requirements: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act, the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120–0056. Related Information (h) Refer to MCAI EASA Airworthiness Directive 2007–0239, dated September 3, 2007, and Airbus Service Bulletins A330–28– 3103, A340–28–4120, and A340–28–5044, all dated July 17, 2007, for related information. Issued in Renton, Washington, on December 10, 2007. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. E7–24519 Filed 12–18–07; 8:45 am] BILLING CODE 4910–13–P attendants to hypoxia following a depressurization event. DATES: We must receive comments on this proposed AD by February 4, 2008. ADDRESSES: You may send comments by any of the following methods: • Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments. • Fax: 202–493–2251. • Mail: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue, SE., Washington, DC 20590. • Hand Delivery: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. For service information identified in this AD, contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124–2207. Examining the AD Docket DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2007–0346; Directorate Identifier 2007–NM–202–AD] RIN 2120–AA64 Airworthiness Directives; Boeing Model 737–300, –400, and –500 Series Airplanes Federal Aviation Administration (FAA), Department of Transportation (DOT). ACTION: Notice of proposed rulemaking (NPRM). rwilkins on PROD1PC63 with PROPOSALS AGENCY: SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) for certain Model 737–300, –400, and –500 series airplanes. This proposed AD would require an inspection to determine the manufacturer and manufacture date of the oxygen masks in the passenger service unit and the lavatory and attendant box assemblies, corrective action if necessary, and other specified action. This proposed AD results from a report that several passenger masks with broken in-line flow indicators were found following a mask deployment. We are proposing this AD to prevent the in-line flow indicators of the passenger oxygen masks from fracturing and separating, which could inhibit oxygen flow to the masks and consequently result in exposure of the passengers and cabin VerDate Aug<31>2005 19:24 Dec 18, 2007 Jkt 214001 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 proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (telephone 800–647–5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt. FOR FURTHER INFORMATION CONTACT: Susan Letcher, Aerospace Engineer, Cabin Safety and Environmental Systems Branch, ANM–150S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057–3356; telephone (425) 917–6474; fax (425) 917–6590. SUPPLEMENTARY INFORMATION: Comments Invited We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include ‘‘Docket No. FAA–2007–0346; Directorate Identifier 2007–NM–202–AD’’ at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those comments. PO 00000 Frm 00003 Fmt 4702 Sfmt 4702 We will post all comments we receive, without change, to http:// www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD. Discussion We have received a report indicating that several passenger masks with broken in-line flow indicators were found following a mask deployment, on a Boeing Model 777–200 series airplane. Operators subsequently found several more broken in-line flow indicators after examining the oxygen mask assemblies on other Model 777 series airplanes and on Model 747–400 series airplanes. Investigation revealed that certain flow indicators are weaker and can fracture because of internal residual stresses caused by the flow indicator joint design and manufacturing processes. Fractures cause the in-line flow indicator to separate and consequently prevent oxygen flow to the mask during an emergency. This condition, if not corrected, could result in exposure of the passengers and cabin attendants to hypoxia following a depressurization event. The oxygen masks on certain Model 777 airplanes and Model 747–400 series airplanes have the same flow indicators as those installed on certain Model 737– 300, –400, and –500 series airplanes. Therefore, the Model 737–300, –400, and –500 series airplanes may be subject to the identified unsafe condition. Relevant Service Information We have reviewed Boeing Special Attention Service Bulletin 737–35– 1099, dated April 9, 2007. The service bulletin describes procedures for doing a general visual inspection to determine the manufacturer and manufacture date of the oxygen masks in the passenger service unit (PSU) and the lavatory and attendant box assemblies. The service bulletin also describes procedures for doing the corrective action if necessary and other specified action. The corrective action includes repairing any B/E Aerospace oxygen mask assembly with a manufacturing date after January 1, 2002, and before March 1, 2006. The service bulletin also specifies that as an alternative to doing the repair (rework), the oxygen mask assembly may be replaced with a new oxygen mask outside the scope of the service bulletin. The other specified action includes doing the oxygen mask drop test. Boeing Special Attention Service Bulletin 737–35–1099 refers to B/E Aerospace Service Bulletin 174080–35– 01, dated February 6, 2006; and E:\FR\FM\19DEP1.SGM 19DEP1 Federal Register / Vol. 72, No. 243 / Wednesday, December 19, 2007 / Proposed Rules Revision 1, dated May 1, 2006; as additional sources of service information for repairing the oxygen mask assembly. B/E Aerospace Service Bulletin 174080–35–01 describes procedures for modifying the oxygen mask assembly by replacing the flow indicator, part number (P/N) 118023–02, with an improved flow indicator, P/N 118023–12. B/E Aerospace Service Bulletin 174080–35–01 also specifies that, as an alternative to modifying the oxygen mask, operators may replace the oxygen mask with a new oxygen mask having the improved flow indicator. Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition. 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. FAA’s Determination and Requirements of the Proposed AD We have evaluated all pertinent information and identified an unsafe condition that is likely to exist or develop on other airplanes of this same type design. For this reason, we are proposing this AD, which would require accomplishing the actions specified in the service information described previously. We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 the proposed regulation: 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); 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. We prepared a regulatory evaluation of the estimated costs to comply with this proposed AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation. Clarification Between the Proposed AD and Service Bulletin Although Boeing Special Attention Service Bulletin 737–35–1099 specifies to repair the oxygen mask assembly, the intent of the service bulletin is to replace it with either a new or modified oxygen mask assembly having an improved flow indicator. Therefore, this proposed AD would require replacing the oxygen mask assembly with a new or modified oxygen mask assembly having an improved flow indicator. rwilkins on PROD1PC63 with PROPOSALS Costs of Compliance There are about 1,956 airplanes of the affected design in the worldwide fleet. This proposed AD would affect about 646 airplanes of U.S. registry. The proposed actions would take about 16 work hours per airplane, for an average of 180 oxygen masks per airplane distributed in about 45 PSU/oxygen boxes, at an average labor rate of $80 per work hour. Required parts would cost about $6 per oxygen mask, or $1,080 per airplane. Based on these figures, the estimated cost of the proposed AD for U.S. operators is $1,524,560, or $2,360 per airplane. 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, VerDate Aug<31>2005 19:24 Dec 18, 2007 Jkt 214001 Regulatory Findings List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Safety. The Proposed Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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. § 39.13 [Amended] 2. The Federal Aviation Administration (FAA) amends § 39.13 PO 00000 Frm 00004 Fmt 4702 Sfmt 4702 71831 by adding the following new airworthiness directive (AD): Boeing: Docket No. FAA–2007–0346; Directorate Identifier 2007–NM–202–AD. Comments Due Date (a) The FAA must receive comments on this AD action by February 4, 2008. Affected ADs (b) None. Applicability (c) This AD applies to Boeing Model 737– 300, –400, and –500 series airplanes, certificated in any category; as identified in Boeing Special Attention Service Bulletin 737–35–1099, dated April 9, 2007. Unsafe Condition (d) This AD results from a report that several passenger masks with broken in-line flow indicators were found following a mask deployment. We are issuing this AD to prevent the in-line flow indicators of the passenger oxygen masks from fracturing and separating, which could inhibit oxygen flow to the masks and consequently result in exposure of the passengers and cabin attendants to hypoxia following a depressurization event. Compliance (e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done. Inspection and Related Investigative/ Corrective Actions if Necessary (f) Within 60 months after the effective date of this AD, do a general visual inspection to determine the manufacturer and manufacture date of the oxygen masks in the passenger service unit and the lavatory and attendant box assemblies, and do the applicable corrective action and other specified action, by accomplishing all of the applicable actions specified in the Accomplishment Instructions of Boeing Special Attention Service Bulletin 737–35– 1099, dated April 9, 2007; except where the service bulletin specifies repairing the oxygen mask assembly, replace it with a new or modified oxygen mask assembly having an improved flow indicator. The corrective action and other specified action must be done before further flight. Note 1: Boeing Special Attention Service Bulletin 737–35–1099 refers to B/E Aerospace Service Bulletin 174080–35–01, dated February 6, 2006; and Revision 1, dated May 1, 2006; as additional sources of service information for modifying the oxygen mask assembly by replacing the flow indicator with an improved flow indicator. Alternative Methods of Compliance (AMOCs) (g)(1) The Manager, Seattle Aircraft Certification Office, FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19. (2) To request a different method of compliance or a different compliance time E:\FR\FM\19DEP1.SGM 19DEP1 71832 Federal Register / Vol. 72, No. 243 / Wednesday, December 19, 2007 / Proposed Rules for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO. Issued in Renton, Washington, on December 10, 2007. Ali Bahrami, Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. E7–24521 Filed 12–18–07; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2007–0345; Directorate Identifier 2007–NM–194–AD] RIN 2120–AA64 Airworthiness Directives; Airbus Model A310–304, –322, –324, and –325 Airplanes; and A300 Model B4–601, B4–603, B4–605R, B4–620, B4–622, B4–622R, F4–605R, F4–622R, and C4– 605R Variant F Airplanes (Commonly Called Model A300–600 Series Airplanes) Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: SUMMARY: We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as: rwilkins on PROD1PC63 with PROPOSALS Due to the recalculation of loads for the Multi Role Transporter and Tanker (MRTT) aircraft, it has been found that a structural reinforcement at the aft section of the fuselage (FR (frame) 87–FR91) is required for A300–600 aircraft and A310 aircraft with a Trim Tank installed. * * * The unsafe condition is the potential loss of structural integrity in the aft section of the fuselage between FR87 through FR91, inclusive, during extreme rolling and vertical maneuver combinations. The proposed AD would require actions that are intended to address the unsafe condition described in the MCAI. DATES: We must receive comments on this proposed AD by January 18, 2008. ADDRESSES: You may send comments by any of the following methods: VerDate Aug<31>2005 19:24 Dec 18, 2007 Jkt 214001 • Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments. • Fax: (202) 493–2251. • Mail: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue, SE., Washington, DC 20590. • Hand Delivery: U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–40, 1200 New Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. 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 this proposed AD, 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. FOR FURTHER INFORMATION CONTACT: Tom Stafford, Aerospace Engineer, International Branch, ANM–116, Transport Airplane Directorate, FAA, 1601 Lind Avenue, SW., Renton, Washington 98057–3356; telephone (425) 227–1622; fax (425) 227–1149. SUPPLEMENTARY INFORMATION: Comments Invited We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include ‘‘Docket No. FAA–2007–0345; Directorate Identifier 2007–NM–194–AD’’ at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD based on those comments. We will post all comments we receive, without change, to http:// www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD. Discussion The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Community, has issued EASA PO 00000 Frm 00005 Fmt 4702 Sfmt 4702 Airworthiness Directive 2007–0173, dated June 18, 2007 (referred to after this as ‘‘the MCAI’’), to correct an unsafe condition for the specified products. The MCAI states: Due to the recalculation of loads for the Multi Role Transporter and Tanker (MRTT) aircraft, it has been found that a structural reinforcement at the aft section of the fuselage (FR (frame) 87–FR91) is required for A300–600 aircraft and A310 aircraft with a Trim Tank installed. * * * The unsafe condition is the potential loss of structural integrity in the aft section of the fuselage between FR87 through FR91, inclusive, during extreme rolling and vertical maneuver combinations. The corrective action is reinforcing the structure at FR91. Related investigative and corrective actions (reinforcement) include: • Doing a rotating probe inspection for cracking of the fastener holes; • Reaming the fastener holes; and • Contacting Airbus for repair instructions and repairing any crack found in any reamed fastener hole. You may obtain further information by examining the MCAI in the AD docket. Relevant Service Information Airbus has issued Service Bulletins A310–53–2126 and A300–53–6156, both dated November 28, 2006. The actions described in this service information are intended to correct the unsafe condition identified in the MCAI. FAA’s Determination and Requirements of This Proposed AD This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to our bilateral agreement with the State of Design Authority, we have been notified of the unsafe condition described in the MCAI and service information referenced above. We are proposing this AD because we evaluated all pertinent information and determined an unsafe condition exists and is likely to exist or develop on other products of the same type design. Differences Between This AD and the MCAI or Service Information We have reviewed the MCAI and related service information and, in general, agree with their substance. But we might have found it necessary to use different words from those in the MCAI to ensure the AD is clear for U.S. operators and is enforceable. In making these changes, we do not intend to differ substantively from the information provided in the MCAI and related service information. E:\FR\FM\19DEP1.SGM 19DEP1

Agencies

[Federal Register Volume 72, Number 243 (Wednesday, December 19, 2007)]
[Proposed Rules]
[Pages 71830-71832]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E7-24521]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-0346; Directorate Identifier 2007-NM-202-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-300, -400, and -500 
Series Airplanes

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

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain Model 737-300, -400, and -500 series airplanes. This 
proposed AD would require an inspection to determine the manufacturer 
and manufacture date of the oxygen masks in the passenger service unit 
and the lavatory and attendant box assemblies, corrective action if 
necessary, and other specified action. This proposed AD results from a 
report that several passenger masks with broken in-line flow indicators 
were found following a mask deployment. We are proposing this AD to 
prevent the in-line flow indicators of the passenger oxygen masks from 
fracturing and separating, which could inhibit oxygen flow to the masks 
and consequently result in exposure of the passengers and cabin 
attendants to hypoxia following a depressurization event.

DATES: We must receive comments on this proposed AD by February 4, 
2008.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://
www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    For service information identified in this AD, contact Boeing 
Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.

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 proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (telephone 800-647-5527) is in the 
ADDRESSES section. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Susan Letcher, Aerospace Engineer, 
Cabin Safety and Environmental Systems Branch, ANM-150S, FAA, Seattle 
Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
Washington 98057-3356; telephone (425) 917-6474; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2007-0346; 
Directorate Identifier 2007-NM-202-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://
www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We have received a report indicating that several passenger masks 
with broken in-line flow indicators were found following a mask 
deployment, on a Boeing Model 777-200 series airplane. Operators 
subsequently found several more broken in-line flow indicators after 
examining the oxygen mask assemblies on other Model 777 series 
airplanes and on Model 747-400 series airplanes. Investigation revealed 
that certain flow indicators are weaker and can fracture because of 
internal residual stresses caused by the flow indicator joint design 
and manufacturing processes. Fractures cause the in-line flow indicator 
to separate and consequently prevent oxygen flow to the mask during an 
emergency. This condition, if not corrected, could result in exposure 
of the passengers and cabin attendants to hypoxia following a 
depressurization event.
    The oxygen masks on certain Model 777 airplanes and Model 747-400 
series airplanes have the same flow indicators as those installed on 
certain Model 737-300, -400, and -500 series airplanes. Therefore, the 
Model 737-300, -400, and -500 series airplanes may be subject to the 
identified unsafe condition.

Relevant Service Information

    We have reviewed Boeing Special Attention Service Bulletin 737-35-
1099, dated April 9, 2007. The service bulletin describes procedures 
for doing a general visual inspection to determine the manufacturer and 
manufacture date of the oxygen masks in the passenger service unit 
(PSU) and the lavatory and attendant box assemblies. The service 
bulletin also describes procedures for doing the corrective action if 
necessary and other specified action. The corrective action includes 
repairing any B/E Aerospace oxygen mask assembly with a manufacturing 
date after January 1, 2002, and before March 1, 2006. The service 
bulletin also specifies that as an alternative to doing the repair 
(rework), the oxygen mask assembly may be replaced with a new oxygen 
mask outside the scope of the service bulletin. The other specified 
action includes doing the oxygen mask drop test.
    Boeing Special Attention Service Bulletin 737-35-1099 refers to B/E 
Aerospace Service Bulletin 174080-35-01, dated February 6, 2006; and

[[Page 71831]]

Revision 1, dated May 1, 2006; as additional sources of service 
information for repairing the oxygen mask assembly. B/E Aerospace 
Service Bulletin 174080-35-01 describes procedures for modifying the 
oxygen mask assembly by replacing the flow indicator, part number (P/N) 
118023-02, with an improved flow indicator, P/N 118023-12. B/E 
Aerospace Service Bulletin 174080-35-01 also specifies that, as an 
alternative to modifying the oxygen mask, operators may replace the 
oxygen mask with a new oxygen mask having the improved flow indicator.
    Accomplishing the actions specified in the service information is 
intended to adequately address the unsafe condition.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other airplanes 
of this same type design. For this reason, we are proposing this AD, 
which would require accomplishing the actions specified in the service 
information described previously.

Clarification Between the Proposed AD and Service Bulletin

    Although Boeing Special Attention Service Bulletin 737-35-1099 
specifies to repair the oxygen mask assembly, the intent of the service 
bulletin is to replace it with either a new or modified oxygen mask 
assembly having an improved flow indicator. Therefore, this proposed AD 
would require replacing the oxygen mask assembly with a new or modified 
oxygen mask assembly having an improved flow indicator.

Costs of Compliance

    There are about 1,956 airplanes of the affected design in the 
worldwide fleet. This proposed AD would affect about 646 airplanes of 
U.S. registry. The proposed actions would take about 16 work hours per 
airplane, for an average of 180 oxygen masks per airplane distributed 
in about 45 PSU/oxygen boxes, at an average labor rate of $80 per work 
hour. Required parts would cost about $6 per oxygen mask, or $1,080 per 
airplane. Based on these figures, the estimated cost of the proposed AD 
for U.S. operators is $1,524,560, or $2,360 per airplane.

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 have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 the proposed 
regulation:
    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); 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD and placed it in the AD docket. See the 
ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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 Federal Aviation Administration (FAA) amends Sec.  39.13 by 
adding the following new airworthiness directive (AD):

Boeing: Docket No. FAA-2007-0346; Directorate Identifier 2007-NM-
202-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by February 
4, 2008.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 737-300, -400, and -500 
series airplanes, certificated in any category; as identified in 
Boeing Special Attention Service Bulletin 737-35-1099, dated April 
9, 2007.

Unsafe Condition

    (d) This AD results from a report that several passenger masks 
with broken in-line flow indicators were found following a mask 
deployment. We are issuing this AD to prevent the in-line flow 
indicators of the passenger oxygen masks from fracturing and 
separating, which could inhibit oxygen flow to the masks and 
consequently result in exposure of the passengers and cabin 
attendants to hypoxia following a depressurization event.

Compliance

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

Inspection and Related Investigative/Corrective Actions if Necessary

    (f) Within 60 months after the effective date of this AD, do a 
general visual inspection to determine the manufacturer and 
manufacture date of the oxygen masks in the passenger service unit 
and the lavatory and attendant box assemblies, and do the applicable 
corrective action and other specified action, by accomplishing all 
of the applicable actions specified in the Accomplishment 
Instructions of Boeing Special Attention Service Bulletin 737-35-
1099, dated April 9, 2007; except where the service bulletin 
specifies repairing the oxygen mask assembly, replace it with a new 
or modified oxygen mask assembly having an improved flow indicator. 
The corrective action and other specified action must be done before 
further flight.

    Note 1: Boeing Special Attention Service Bulletin 737-35-1099 
refers to B/E Aerospace Service Bulletin 174080-35-01, dated 
February 6, 2006; and Revision 1, dated May 1, 2006; as additional 
sources of service information for modifying the oxygen mask 
assembly by replacing the flow indicator with an improved flow 
indicator.

Alternative Methods of Compliance (AMOCs)

    (g)(1) The Manager, Seattle Aircraft Certification Office, FAA, 
has the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.
    (2) To request a different method of compliance or a different 
compliance time

[[Page 71832]]

for this AD, follow the procedures in 14 CFR 39.19. Before using any 
approved AMOC on any airplane to which the AMOC applies, notify your 
appropriate principal inspector (PI) in the FAA Flight Standards 
District Office (FSDO), or lacking a PI, your local FSDO.

    Issued in Renton, Washington, on December 10, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E7-24521 Filed 12-18-07; 8:45 am]
BILLING CODE 4910-13-P