[Federal Register Volume 71, Number 134 (Thursday, July 13, 2006)]
[Proposed Rules]
[Pages 39593-39595]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E6-11021]


 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
 
 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 71, No. 134 / Thursday, July 13, 2006 / 
Proposed Rules  

[[Page 39593]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-25336; Directorate Identifier 2006-NM-070-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-300, -400, -500, -600, 
-700, -800 and -900 Series Airplanes; and Model 757-200 and -300 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 Boeing Model 737-300, -400, -500, -600, -700, -800 and -900 
series airplanes; and Model 757-200 and -300 series airplanes. This 
proposed AD would require modifying the activation mechanism in the 
chemical oxygen generator of each passenger service unit (PSU). This 
proposed AD results from several reports indicating that some chemical 
oxygen generators failed to activate during in-flight decompression 
events. These failures were due to fracture of components between the 
passenger oxygen mask and the release pin in the oxygen generator. We 
are proposing this AD to prevent failure of the activation mechanism of 
the chemical oxygen generator, which could result in the unavailability 
of supplemental oxygen and possible incapacitation of passengers and 
cabin crew during an in-flight decompression.

DATES: We must receive comments on this proposed AD by August 28, 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 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-2006-
25336; Directorate Identifier 2006-NM-070-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 several reports indicating that some chemical 
oxygen generators failed to activate during in-flight decompression 
events. These failures were due to fracture of components between the 
passenger oxygen mask and the release pin in the oxygen generator. The 
release pin must be pulled out of the oxygen generator firing mechanism 
to activate the generator. The fractures occur when a passenger 
encounters resistance when attempting to pull down the oxygen mask. The 
system is designed so that when a mask is pulled down for donning, a 
lanyard attached to the mask pulls down on a release cable within the 
passenger service unit (PSU). The release cable is attached to a pin in 
the oxygen generator firing mechanism. Downward pressure applied on the 
release cable when the mask is pulled down causes the pin to be pulled 
out of the firing mechanism, activating the generator and starting the 
flow of oxygen to the masks. If excessive resistance occurs when 
pulling down the mask, the components between the mask and the 
generator release pin can break, such as the tab that connects the 
oxygen mask to the lanyard or the ring that attaches the lanyard to the 
release cable. Failure of the activation mechanism of the chemical 
oxygen generator could result in the unavailability of supplemental 
oxygen and possible incapacitation of passengers and cabin crew during 
an in-flight decompression.

Relevant Service Information

    We have reviewed the service bulletins identified in the following 
table. The service bulletins describe

[[Page 39594]]

procedures for modifying the activation mechanism in the chemical 
oxygen generator of each PSU. The modification includes replacing the 
oxygen generator release pin; reworking the center cable guides; 
replacing the pulley guards/covers, and adding a pulley configuration 
placard.

                            Service Bulletins
------------------------------------------------------------------------
                                                  Applicable to model/
  Boeing special attention service bulletin             series--
------------------------------------------------------------------------
737-25-1545, dated September 8, 2005.........  737-600, -700, -800, and
                                                900.
737-25-1548, dated November 22, 2005.........  737-300, -400, and -500.
757-25-0284, dated November 22, 2005.........  757-200.
757-25-0285, dated November 22, 2005.........  757-300.
------------------------------------------------------------------------

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.

Costs of Compliance

    There are about 3,283 airplanes of the affected design in the 
worldwide fleet. This proposed AD would affect about 815 airplanes of 
U.S. registry. The proposed modification would take about 1 work hour 
per PSU, per airplane, at an average labor rate of $80 per work hour. 
Required parts would cost between $68 and $75 per PSU, per airplane. 
Based on these figures, the estimated cost of the modification proposed 
by this AD for U.S. operators is between $148 and $155 per PSU, 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-2006-25336; Directorate Identifier 2006-NM-
070-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by August 
28, 2006.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 737-300, -400, -500, -600, -
700, -800 and -900 series airplanes; and Model 757-200 and -300 
series airplanes; certificated in any category; as identified in the 
applicable service bulletin in Table 1 of this AD.

                       Table 1.--Service Bulletins
------------------------------------------------------------------------
  Boeing special attention                          Applicable to model/
      service  bulletin               Date                 series
------------------------------------------------------------------------
737-25-1545.................  September 8, 2005...  737-600, -700, -800,
                                                     and -900.
737-25-1548.................  November 22, 2005...  737-300, -400, and -
                                                     500.
757-25-0284.................  November 22, 2005...  757-200.
757-25-0285.................  November 22, 2005...  757-300.
------------------------------------------------------------------------


[[Page 39595]]

Unsafe Condition

    (d) This AD results from several reports indicating that some 
chemical oxygen generators failed to activate during in-flight 
decompression events. These failures were due to fracture of 
components between the passenger oxygen mask and the release pin in 
the oxygen generator. We are issuing this AD to prevent failure of 
the activation mechanism of the chemical oxygen generator, which 
could result in the unavailability of supplemental oxygen and 
possible incapacitation of passengers and cabin crew during an in-
flight decompression.

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.

Modification

    (f) Within 60 months after the effective date of this AD: Modify 
the activation mechanism in the chemical oxygen generator of each 
passenger service unit (PSU) by doing all the applicable actions 
specified in the Accomplishment Instructions of the applicable 
service bulletin in Table 1 of this AD.

Alternative Methods of Compliance (AMOCs)

    (g)(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 Sec.  
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 July 6, 2006.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E6-11021 Filed 7-12-06; 8:45 am]
BILLING CODE 4910-13-P