
[Federal Register Volume 78, Number 47 (Monday, March 11, 2013)]
[Proposed Rules]
[Pages 15332-15335]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-05505]


 ========================================================================
 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. 78, No. 47 / Monday, March 11, 2013 / 
Proposed Rules  

[[Page 15332]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2013-0207; Directorate Identifier 2011-NM-071-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: We propose to supersede an existing airworthiness directive 
(AD) that applies to all The Boeing Company Model 737-300, -400, and -
500 series airplanes. The existing AD currently requires repetitive 
inspections of the downstop assemblies on the main tracks of the No. 2, 
3, 4, and No. 5 slats and the inboard track of the No. 1 and 6 slats to 
verify if any parts are missing, damaged, or in the wrong order; other 
specified actions; and related investigative and corrective actions if 
necessary. Since we issued that AD, the manufacturer has developed a 
modification, which, when installed, would terminate the repetitive 
inspections. This proposed AD would add an inspection of the slat can 
interior for foreign object debris (FOD), and removal of any FOD found; 
modification of the slat track hardware; an inspection for FOD and for 
damage to the interior surface of the slat cans; and related 
investigative and corrective actions, if necessary. We are proposing 
this AD to prevent loose or missing parts in the main slat track 
downstop assemblies, which could puncture the slat track housing and 
result in a fuel leak and consequent fire.

DATES: We must receive comments on this proposed AD by April 25, 2013.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, 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: Deliver to Mail address above 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, 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.

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 (phone: 800-647-5527) is in the ADDRESSES 
section. Comments will be available in the AD docket shortly after 
receipt.

FOR FURTHER INFORMATION CONTACT: Nancy Marsh, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office 
(ACO), 1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: 
(425) 917-6440; fax: (425) 917-6590; email: nancy.marsh@faa.gov.

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-2013-0207; 
Directorate Identifier 2011-NM-071-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 11, 2008, we issued AD 2008-06-29, Amendment 39-15441 (73 
FR 15397, March 24, 2008), for all The Boeing Company Model 737-300, -
400, and -500 series airplanes. That AD requires repetitive inspections 
of the downstop assemblies on the main tracks of the No. 2, 3, 4, and 5 
slats and the inboard track of the No. 1 and 6 slats to verify if any 
parts are missing, damaged, or in the wrong order; and related 
investigative and corrective actions if necessary. That AD resulted 
from reports of fuel leaking from a puncture in the slat track housing. 
We issued that AD to detect and correct loose or missing parts in the 
main slat track downstop assemblies, which could puncture the slat 
track housing and result in a fuel leak and consequent fire.

Actions Since Existing AD (73 FR 15397, March 24, 2008) Was Issued

    The preamble to AD 2008-06-29, Amendment 39-15441 (73 FR 15397, 
March 24, 2008), specifies that we consider the requirements ``interim 
action'' and that the manufacturer was developing a modification to 
address the unsafe condition. That AD explains that we might consider 
further rulemaking if a modification is developed, approved, and 
available. The manufacturer now has developed such a modification, and 
we have determined that further rulemaking is indeed necessary; this 
proposed AD follows from that determination.

Relevant Service Information

    AD 2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008), 
refers to Boeing Alert Service Bulletin 737-57A1301, dated February 5, 
2008, as the appropriate source of service information for the required 
actions.

[[Page 15333]]

Boeing has since revised this service information. We reviewed Boeing 
Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011, which 
adds procedures for inspecting the slat can interior for foreign object 
debris (FOD), removing any FOD found, modifying the slat track 
hardware; an inspection for FOD and a one-time inspection for damage to 
the interior surface of the slat cans for the inboard and outboard 
tracks of slats No. 2 through 5 and the inboard slats of tracks No. 1 
and 6; and related investigative and corrective actions if necessary. 
Modifying the slat track hardware eliminates the need for the 
repetitive inspections.
    Related investigative actions include a determination of the wall 
thickness of damaged slat cans, and an inspection for clearance between 
the bottom of the slat can and slat main track. Corrective actions 
include a blend-out repair or replacement of the slat can with a new or 
serviceable slat can, proper torque of nuts, and installation of a 
tapered filler.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Proposed AD Requirements

    This proposed AD would retain all requirements of AD 2008-06-29, 
Amendment 39-15441 (73 FR 15397, March 24, 2008), and also would 
require the actions specified in the service information described 
previously.

Change to Existing AD (73 FR 15397, March 24, 2008)

    This proposed AD would retain all requirements of AD 2008-06-29, 
Amendment 39-15441 (73 FR 15397, March 24, 2008). Since AD 2008-06-29 
was issued, the AD format has been revised, and certain paragraphs have 
been rearranged. As a result, the corresponding paragraph identifiers 
have changed in this proposed AD, as listed in the following table:

                      Revised Paragraph Identifiers
------------------------------------------------------------------------
   Requirement in AD 2008-06-29,
   Amendment 39[dash]15441 (73 FR     Corresponding requirement in this
       15397, March 24, 2008)                    proposed AD
------------------------------------------------------------------------
           paragraph (d)                        paragraph (e)
           paragraph (e)                        paragraph (f)
           paragraph (f)                        paragraph (g)
------------------------------------------------------------------------

    In addition, Boeing Commercial Airplanes has received an 
Organization Designation Authorization (ODA), which replaces the 
previous designation as a Delegation Option Authorization (DOA) holder. 
We have revised paragraph (k) of this proposed AD to add delegation of 
authority to Boeing Commercial Airplanes ODA to approve an alternative 
method of compliance for certain repairs required by this proposed AD.

Costs of Compliance

    We estimate that this proposed AD affects 568 airplanes of U.S. 
registry.
    We estimate the following costs to comply with this proposed AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                       Cost on
                  Action                                Labor cost               Parts     Cost per      U.S.
                                                                                  cost     product    operators
----------------------------------------------------------------------------------------------------------------
Inspection of slat track housing [retained  4 work-hours x $85 per hour =             $0       $340     $193,120
 actions from existing AD                    $340 per inspection cycle.
 2008[dash]06[dash]29, Amendment 39-15441,
 (73 FR 15397, March 24, 2008)].
One-time detailed inspection of slat can    5 work-hours x $85 per hour = $85         $0       $425     $241,400
 [new proposed action].
Installation of modification [new proposed  12 work-hours x $85 per hour =        $3,124     $4,144   $2,353,792
 action].                                    $1,020.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
a cost estimate for the on-condition actions specified in this proposed 
AD.

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),
    (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.

[[Page 15334]]

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

0
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]

0
2. The FAA amends Sec.  39.13 by removing airworthiness directive (AD) 
2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008), and 
adding the following new AD:

The Boeing Company: Docket No. FAA-2013-0207; Directorate Identifier 
2011-NM-071-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by April 25, 
2013.

(b) Affected ADs

    This AD supersedes AD 2008-06-29, Amendment 39-15441 (73 FR 
15397, March 24, 2008).

(c) Applicability

    This AD applies to all The Boeing Company Model 737-300, -400, 
and -500 series airplanes, certificated in any category.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 57: Wings.

(e) Unsafe Condition

    This AD was prompted by reports of fuel leaking from a puncture 
in the slat track housing (referred to as ``slat can''). We are 
issuing this AD to prevent loose or missing parts in the main slat 
track downstop assemblies, which could puncture the slat track 
housing and result in a fuel leak and consequent fire.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Retained Inspection of Downstop Assemblies and Corrective Action

    This paragraph restates the requirements of paragraph (f) of AD 
2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008), with 
revised service information. At the applicable times specified in 
Table 1 of paragraph 1.E. of Boeing Service Bulletin 737-57A1301, 
dated February 5, 2008; or Boeing Alert Service Bulletin 737-
57A1301, Revision 3, dated August 11, 2011; except as provided by 
paragraph (g)(1) of this AD: Do a detailed inspection or borescope 
inspection of the downstop assemblies on the main tracks of the No. 
2, 3, 4, and 5 slats and the inboard track of the No. 1 and 6 slats 
to verify if any parts are missing, damaged, or installed in the 
wrong order; and do all the other specified, related investigative, 
and corrective actions as applicable; by accomplishing all of the 
applicable actions specified in the Accomplishment Instructions of 
Boeing Alert Service Bulletin 737-57A1301, dated February 5, 2008; 
or Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 
2011; except as provided by paragraphs (g)(2) and (g)(3) of this AD. 
Repeat the inspection thereafter at the applicable times specified 
in Table 1 of paragraph 1.E. of Boeing Service Bulletin 737-57A1301, 
dated February 5, 2008; or Boeing Alert Service Bulletin 737-
57A1301, Revision 3, dated August 11, 2011. Do all applicable 
related investigative and corrective actions before further flight. 
As of the effective date of this AD, only Boeing Service Bulletin 
737-57A1301, Revision 3, dated August 11, 2011, may be used to 
accomplish the actions required by this paragraph.
    (1) Where Boeing Alert Service Bulletin 737-57A1301, dated 
February 5, 2008, or Boeing Service Bulletin 737-57A1301, Revision 
3, dated August 11, 2011, specifies counting the compliance time 
from ``the date on the service bulletin,'' this AD requires counting 
the compliance time from April 8, 2008 (the effective date of AD 
2008-06-29, Amendment 39-15441 (73 FR 15397, March 24, 2008)).
    (2) For airplanes on which any downstop assembly part is missing 
or damaged, a borescope inspection of the inside of the slat track 
housing for loose parts and damage to the wall of the slat track 
housing may be accomplished in lieu of the detailed inspection of 
the inside of the slat track housing that is specified in Boeing 
Alert Service Bulletin 737-57A1301, dated February 5, 2008; or 
Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 
2011. As of the effective date of this AD, only Boeing Service 
Bulletin 737-57A1301, Revision 3, dated August 11, 2011, may be used 
to do the actions specified in this paragraph.
    (3) If any damaged slat track housing is found during any 
inspection required by paragraph (g) of this AD: Before further 
flight, repair in accordance with the Accomplishment Instructions of 
Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 
2011; replace the slat can with a new slat can having the same part 
number, in accordance with the Accomplishment Instructions of Boeing 
Service Bulletin 737-57A1301, Revision 3, dated August 11, 2011; or 
repair the slat can using a method approved in accordance with the 
procedures specified in paragraph (k) of this AD.

(h) New Detailed Inspection for Foreign Object Debris (FOD)

    Within 24 months after the effective date of this AD, do a one-
time detailed inspection of the slat can interior to detect FOD, in 
accordance with Part III of the Accomplishment Instructions of 
Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 
2011. If any FOD is found, before further flight, remove it, in 
accordance with the Accomplishment Instructions of Boeing Service 
Bulletin 737-57A1301, Revision 3, dated August 11, 2011.

(i) New Modification and Inspection

    Within 72 months or 15,000 flight cycles, whichever occurs 
first, after the effective date of this AD: Modify the slat track 
hardware by installing new downstop assembly hardware, and do a 
detailed inspection for FOD and a one-time inspection for damage to 
the interior surface of the slat can for the inboard and outboard 
tracks of slats 2 through 5, and the inboard slats of tracks 1 and 
6; and do all applicable related investigative and corrective 
actions; in accordance with the Accomplishment Instructions of 
Boeing Service Bulletin 737-57A1301, Revision 3, dated August 11, 
2011. Do all applicable related investigative and corrective actions 
before further flight. Accomplishment of the actions required by 
this paragraph terminates the inspections required by paragraphs (g) 
and (h) of this AD.

(j) Credit for Previous Actions

    This paragraph provides credit for the actions required by 
paragraphs (g), (h), and (i) of this AD, if those actions were 
performed before the effective date of this AD using Boeing Alert 
Service Bulletin 737-57A1301, Revision 1, dated September 24, 2009; 
or Boeing Alert Service Bulletin 737-57A1301, Revision 2, dated 
January 17, 2011; which are not incorporated by reference in this 
AD.

(k) 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: 9-ANM-Seattle-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.
    (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 the 
Boeing Commercial Airplanes Organization Designation Authorization 
(ODA) that 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, and the approval must 
specifically refer to this AD.
    (4) AMOCs approved previously in accordance with AD 2008-06-29, 
Amendment 39-15441 (73 FR 15397, March 24, 2008), are approved as 
AMOCs for the corresponding provisions of this AD.

[[Page 15335]]

(l) Related Information

    (1) For more information about this AD, contact Nancy Marsh, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft 
Certification Office (ACO), 1601 Lind Avenue SW., Renton, WA 98057-
3356; phone: (425) 917-6440; fax: (425) 917-6590; email: 
nancy.marsh@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.

    Issued in Renton, Washington, on February 28, 2013.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-05505 Filed 3-8-13; 8:45 am]
BILLING CODE 4910-13-P


