[Federal Register Volume 70, Number 236 (Friday, December 9, 2005)]
[Proposed Rules]
[Pages 73171-73173]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-23833]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-23250; Directorate Identifier 2005-NM-150-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-400 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 adopt a new airworthiness directive (AD) 
for certain Boeing Model 747-400 series airplanes. This proposed AD 
would require inspecting the support bracket of the crew oxygen 
cylinder installation to determine the manufacturing date marked on the 
support, and performing corrective action if necessary. This proposed 
AD results from a report indicating that certain oxygen cylinder 
supports may not have been properly heat-treated. We are proposing this 
AD to prevent failure of the oxygen cylinder support under the most 
critical flight load conditions, which could cause the oxygen cylinder 
to come loose and leak oxygen. Leakage of oxygen could result in oxygen 
being unavailable for the flightcrew or could result in a fire hazard 
in the vicinity of the leakage.

DATES: We must receive comments on this proposed AD by January 23, 
2006.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD.
     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 400

[[Page 73172]]

Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC 
20590.
     Fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207, for the service information identified in this 
proposed AD.

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 98055-4056; telephone (425) 917-6474; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to submit any relevant written data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed in the ADDRESSES section. Include the docket number ``FAA-2005-
23250; Directorate Identifier 2005-NM-150-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the proposed AD. We will 
consider all comments received by the closing date and may amend the 
proposed AD in light of those comments.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this proposed AD. Using the search function of 
that web site, anyone can find and read the comments in any of our 
dockets, including the name of the individual who sent the comment (or 
signed the comment on behalf of an association, business, labor union, 
etc.). You may review DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78), or you 
may visit http://dms.dot.gov.

Examining the Docket

    You may examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Management Facility office (telephone (800) 647-
5227) is located on the plaza level of the Nassif Building at the DOT 
street address stated in the ADDRESSES section. Comments will be 
available in the AD docket shortly after the Docket Management System 
receives them.

Discussion

    We have received a report indicating that certain supports for the 
crew oxygen cylinder on Boeing Model 747-400 series airplanes may not 
have been properly heat-treated during production. These improperly 
heat-treated supports could fail under the most critical flight load 
conditions, which could cause the oxygen cylinder to come loose and 
leak oxygen. Leakage of oxygen could result in oxygen being unavailable 
for the flightcrew or could result in a fire hazard in the vicinity of 
the leakage.

Relevant Service Information

    We have reviewed Boeing Special Attention Service Bulletin 747-35-
2114, dated December 19, 2002. The service bulletin describes 
procedures for inspecting the support bracket of the crew oxygen 
cylinder installation to determine the manufacturing date marked on the 
support, and performing corrective action if necessary. The corrective 
action is replacing, with a new support, any support with a 
manufacturing date that is within a certain range. 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, except as discussed under 
``Differences Between the Proposed AD and Service Bulletin.''

Differences Between the Proposed AD and Service Bulletin

    The service bulletin specifies a compliance time of 90 days (for 
airplanes with two crew oxygen cylinders) or 18 months (for airplanes 
with one crew oxygen cylinder). However, this proposed AD would require 
all airplanes to be in compliance within 18 months after the effective 
date of the AD. In developing an appropriate compliance time for this 
AD, we considered the manufacturer's recommendation, and the degree of 
urgency associated with the subject unsafe condition. In light of these 
factors, we find that an 18-month compliance time represents an 
appropriate interval of time for affected airplanes to continue to 
operate without compromising safety. This difference has been 
coordinated with Boeing.
    Also, paragraph 1.E., Compliance, of the service bulletin specifies 
that if the configuration of the crew oxygen cylinder installation is 
changed from a one-cylinder configuration to a two-cylinder 
configuration, the actions specified in the service bulletin must be 
done ``immediately.'' If the configuration of the crew oxygen cylinder 
support installation is changed in this way, this proposed AD would 
require you to do the actions in the service bulletin before further 
flight after the configuration change, or within 18 months after the 
effective date of the AD, whichever is later.

Costs of Compliance

    There are about 70 airplanes of the affected design in the 
worldwide fleet. This proposed AD would affect about 15 airplanes of 
U.S. registry. The proposed inspection would take about 1 work hour per 
airplane, at an average labor rate of $65 per work hour. Based on these 
figures, the estimated cost of the proposed AD for U.S. operators is 
$975, or $65 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

[[Page 73173]]

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-2005-23250; Directorate Identifier 2005-NM-
150-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by January 
23, 2006.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 747-400 series airplanes, 
certificated in any category, as identified in Boeing Special 
Attention Service Bulletin 747-35-2114, dated December 19, 2002.

Unsafe Condition

    (d) This AD results from a report indicating that certain oxygen 
cylinder supports may not have been properly heat-treated. We are 
issuing this AD to prevent failure of the oxygen cylinder support 
under the most critical flight load conditions, which could cause 
the oxygen cylinder to come loose and leak oxygen. Leakage of oxygen 
could result in oxygen being unavailable for the flightcrew or could 
result in a fire hazard in the vicinity of the leakage.

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 Corrective Action

    (f) Within 18 months after the effective date of this AD, except 
as provided by paragraph (g) of this AD: Inspect the support bracket 
of the crew oxygen cylinder installation to determine the 
manufacturing date marked on the support, and do the corrective 
action as applicable, by doing all of the actions in accordance with 
the Accomplishment Instructions of Boeing Special Attention Service 
Bulletin 747-35-2114, dated December 19, 2002. Corrective action, if 
applicable, must be done before further flight after the inspection.
    (g) If the configuration of the crew oxygen cylinder 
installation is changed from a one-cylinder to a two-cylinder 
configuration: Do the actions required by paragraph (f) of this AD 
before further flight after the change in configuration, or within 
18 months after the effective date of this AD, whichever is later.

Parts Installation

    (h) On or after the effective date of this AD, no person may 
install an oxygen cylinder support bracket having part number 
65B68258-2 and having a manufacturing date between 10/01/98 and 03/
09/01 inclusive (meaning, a manufacturing date of 10/01/98 or later 
and 03/09/01 or earlier).

Alternative Methods of Compliance (AMOCs)

    (i)(1) The Manager, Seattle Aircraft Certification Office (ACO), 
FAA, has the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.
    (2) Before using any AMOC approved in accordance with 14 CFR 
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.

    Issued in Renton, Washington, on December 2, 2005.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-23833 Filed 12-8-05; 8:45 am]
BILLING CODE 4910-13-P