
[Federal Register: December 30, 2009 (Volume 74, Number 249)]
[Proposed Rules]               
[Page 69040-69042]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr30de09-14]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2009-1224; Directorate Identifier 2009-NM-118-AD]
RIN 2120-AA64

 
Airworthiness Directives; The Boeing Company Model 737-200, -300, 
-400, and -500 Series Airplanes

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

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede an existing airworthiness 
directive (AD) that applies to certain Model 737-300, -400, and -500 
series airplanes. The existing AD currently requires 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 would expand the applicability in the existing AD. 
This AD results from a determination indicating that additional 
airplanes may be subject to the identified unsafe condition. 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 16, 
2010.

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 proposed AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, P. 
O. Box 3707,

[[Page 69041]]

MC 2H-65, Seattle, Washington 98124-2207; telephone 206-544-5000, 
extension 1, fax 206-766-5680; e-mail me.boecom@boeing.com; 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 or 425-227-
1152.

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: Robert Hettman, 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) 917-6457; 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-2009-1224; 
Directorate Identifier 2009-NM-118-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

    On March 9, 2008, we issued AD 2008-06-24, Amendment 39-15436 (73 
FR 14666, March 19, 2008), for certain Model 737-300, -400, and -500 
series airplanes. That AD requires 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 actions. That AD resulted from 
a report that several passenger masks with broken in-line flow 
indicators were found following a mask deployment. We issued that 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.

Actions Since Existing AD Was Issued

    Since we issued AD 2008-06-24, we have determined that the oxygen 
masks on the affected Model 737-300, -400, and -500 series airplanes 
have the same flow indicators as those installed on certain Model 737-
200 series airplanes; therefore, Model 737-200 series airplanes may be 
also subject to the identified unsafe condition.

Relevant Service Information

    We have reviewed Boeing Special Attention Service Bulletin 737-35-
1099, Revision 1, dated April 23, 2009. The specified actions are 
essentially identical to those specified in Boeing Special Attention 
Service Bulletin 737-35-1099, dated April 9, 2007 (which we cited in 
the existing AD). Revision 1 of Boeing Special Attention Service 
Bulletin 737-35-1099 expands the effectivity of the service bulletin by 
adding Model 737-200 series airplanes that may have been delivered with 
B/E Aerospace oxygen assemblies, identified in B/E Aerospace Service 
Bulletin 174080-35-01, before January 1, 2002, and that have had the 
oxygen mask assemblies replaced with assemblies manufactured between 
January 1, 2002, and March 1, 2006. B/E Aerospace Service Bulletin 
174080-35-01 was referred to in the existing AD as an additional source 
of guidance for modifying the oxygen mask assembly.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to develop on other products of the 
same type design. For this reason, we are proposing this AD, which 
would supersede AD 2008-06-24 and would retain the requirements of the 
existing AD. This proposed AD would expand the applicability to include 
Model 737-200 series airplanes.

Costs of Compliance

    There are about 1,981 airplanes of the affected design in the 
worldwide fleet. This proposed AD would affect about 666 airplanes of 
U.S. registry.
    The actions that are required by AD 2008-06-24 and retained in this 
proposed AD affect about 646 airplanes of U.S. registry. The required 
actions take about 16 work hours per airplane, for an average of 180 
oxygen masks per airplane distributed in about 45 PSUs/oxygen boxes, at 
an average labor rate of $80 per work hour. Required parts cost about 
$6 per oxygen mask, or $1,080 per airplane. Based on these figures, the 
estimated cost of the existing AD for U.S. operators is $1,524,560, or 
$2,360 per airplane.
    This proposed AD would be applicable to approximately 20 additional 
airplanes. Based on the figures discussed above, we estimate the costs 
for the additional airplanes imposed by this proposed AD on U.S. 
operators to be $47,200, or $2,360 per airplane. This figure is based 
on assumptions that no operator of these additional airplanes has yet 
done any of the proposed requirements of this AD, and that no operator 
would do those actions in the future if this AD were not adopted.

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

[[Page 69042]]

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, Incorporation by 
reference, 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 FAA amends Sec.  39.13 by removing Amendment 39-15436 (73 FR 
14666, March 19, 2008) and adding the following new AD:

The Boeing Company: Docket No. FAA-2009-1224; Directorate Identifier 
2009-NM-118-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by February 
16, 2010.

Affected ADs

    (b) This AD supersedes AD 2008-06-24, Amendment 39-15436.

Applicability

    (c) This AD applies to The Boeing Company Model 737-200, -300, -
400, and -500 series airplanes, certificated in any category; as 
identified in Boeing Special Attention Service Bulletin 737-35-1099, 
Revision 1, dated April 23, 2009.

Subject

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

Unsafe Condition

    (e) The existing AD results from a report of a sudden decrease 
in cabin pressure and deployment of the passenger oxygen mask 
assemblies; several masks had broken in-line flow indicators. The 
Federal Aviation Administration is 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

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

Restatement of Requirements of AD 2008-06-24, with New Service 
Information

Inspection and Related Investigative/Corrective Actions if 
Necessary

    (g) For airplanes identified in Boeing Special Attention Service 
Bulletin 737-35-1099, dated April 9, 2007: Within 60 months after 
April 23, 2008 (the effective date of AD 2008-06-24), 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; or Revision 1, dated April 23, 2009; 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. As of the effective date 
of this AD, use only Revision 1 of Boeing Special Attention Service 
Bulletin 737-35-1099.

New Requirements of This AD

Inspection and Related Investigative/Corrective Actions if 
Necessary

    (h) For airplanes other than those identified in paragraph (g) 
of this AD: 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, Revision 1, dated April 23, 2009; 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, 
dated April 9, 2007; and Revision 1, dated April 23, 2009; refer to 
B/E Aerospace Service Bulletin 174080-35-01, dated February 6, 2006; 
Revision 1, dated May 1, 2006; and Revision 2, dated May 28, 2008; 
as additional sources of guidance for modifying the oxygen mask 
assembly by replacing the flow indicator with an improved flow 
indicator.

Parts Installation

    (i) As of the effective date of this AD, no person may install a 
B/E Aerospace oxygen mask assembly having a part number in the 
174080 series or 174095 series with a manufacturing date after 
January 1, 2002, and before March 1, 2006, on any airplane, unless 
it has been modified in accordance with the requirements of 
paragraph (g) or (h) of this AD.

Credit for Actions Done In Accordance With Previous Issue of the 
Service Bulletin

    (j) Actions done before the effective date of this AD, in 
accordance with Boeing Special Attention Service Bulletin 737-35-
1099, dated April 9, 2007, are acceptable for compliance with the 
requirements of paragraph (g) of this AD.

Alternative Methods of Compliance (AMOCs)

    (k)(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. Send information to 
ATTN: Robert Hettman, 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) 917-6457; fax (425) 917-6590. Or, e-mail 
information to 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.
    (2) To request a different method of compliance or a different 
compliance time 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 principal maintenance inspector (PMI) or 
principal avionics inspector (PAI), as appropriate, or lacking a 
principal inspector, your local Flight Standards District Office. 
The AMOC approval letter must specifically reference this AD.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD, if it is approved by an 
Authorized Representative for the Boeing Commercial Airplanes 
Delegation Option Authorization Organization who has been authorized 
by the Manager, Seattle ACO, to make those findings. For a repair 
method to be approved, the repair must meet the certification basis 
of the airplane.

    Issued in Renton, Washington, on December 21, 2009.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E9-30902 Filed 12-29-09; 8:45 am]

BILLING CODE 4910-13-P
