
[Federal Register Volume 78, Number 101 (Friday, May 24, 2013)]
[Rules and Regulations]
[Pages 31389-31394]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-10797]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0855; Directorate Identifier 2011-NM-136-AD; 
Amendment 39-17452; AD 2013-09-10]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are superseding an existing airworthiness directive (AD) 
for all The Boeing Company Model 737-100, -200, -200C, -300, -400, and 
-500 series airplanes. That AD currently requires repetitive 
inspections to detect cracking of the lower corners of the door frame 
and cross beam of the forward cargo door, and corrective actions if 
necessary. That AD also requires eventual modification of the outboard 
radius of the lower corners of the door frame and reinforcement of the 
cross beam of the forward cargo door, which terminates the existing 
repetitive inspections. This new AD revises the compliance times for 
the preventive modification; adds certain inspections for cracks in the 
number 5 cross beam of the forward cargo door; and adds inspections of 
the number 4 cross beam if cracks are found in the number 5 cross beam, 
and corrective actions if necessary. For certain airplanes, this

[[Page 31390]]

new AD also adds a one-time inspection for airplanes previously 
modified or repaired, and a one-time inspection of the reinforcement 
angle for excessive shimming or fastener pull-up, and corrective 
actions if necessary. This AD was prompted by additional reports of 
fatigue cracking in the radius of the lower frames and in the lower 
number 5 cross beam of the forward cargo door. We are issuing this AD 
to prevent fatigue cracking of the lower corners of the door frame and 
number 5 cross beam of the forward cargo door, which could result in 
rapid depressurization of the airplane.

DATES: This AD is effective June 28, 2013.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in the AD as of June 28, 2013.
    The Director of the Federal Register approved the incorporation by 
reference of certain other publications listed in this AD as of May 16, 
2000 (65 FR 19302, April 11, 2000).

ADDRESSES: 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.

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 AD, the regulatory evaluation, 
any comments received, and other information. The address for the 
Docket Office (phone: 800-647-5527) is Document Management Facility, 
U.S. Department of Transportation, Docket Operations, M-30, West 
Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., 
Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Alan Pohl, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: (425) 917-
6450; fax: (425) 917-6590; email: alan.pohl@faa.gov.

SUPPLEMENTARY INFORMATION: 

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to supersede airworthiness directive (AD) 2000-07-06, Amendment 
39-11660 (65 FR 19302, April 11, 2000). That AD applies to the 
specified products. The NPRM published in the Federal Register on 
August 21, 2012 (77 FR 50407). The NPRM proposed to continue to require 
repetitive inspections to detect cracking of the lower corners of the 
door frame and cross beam of the forward cargo door, and corrective 
actions if necessary. The NPRM also proposed to continue to require 
eventual modification of the outboard radius of the lower corners of 
the door frame and reinforcement of the cross beam of the forward cargo 
door, which would constitute terminating action for the existing 
repetitive inspections. Additionally, the NPRM proposed to revise the 
compliance times for the preventive modification; add certain 
inspections for cracks in the number 5 cross beam of the forward cargo 
door; and add inspections of the number 4 cross beam if cracks are 
found in the number 5 cross beam, and corrective actions if necessary. 
For certain airplanes, the NPRM also proposed to add a one-time 
inspection for airplanes previously modified or repaired, and a one-
time inspection of the reinforcement angle for excessive shimming or 
fastener pull-up, and corrective actions if necessary.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the proposal 
(77 FR 50407, August 21, 2012) and the FAA's response to each comment.

Comment Regarding Winglet Supplemental Type Certificate (STC)

    Aviation Partners Boeing stated that installation of winglets per 
STC ST01219SE (http://rgl.faa.gov/regulatory_and_guidance_library/rgstc.nsf/0/2C6E3DBDDD36F91C862576A4005D64E2?OpenDocument&Highlight=st01219se) does 
not affect the ability to accomplish the service information or the 
NPRM (77 FR 50407, August 21, 2012).
    We have revised paragraph (c) in this final rule, by adding new 
paragraph (c)(2), to state that installation of STC ST01219SE (http://rgl.faa.gov/regulatory_and_guidance_library/rgstc.nsf/0/2C6E3DBDDD36F91C862576A4005D64E2?OpenDocument&Highlight=st01219se) does 
not affect the ability to accomplish the actions required by this AD. 
Therefore, for airplanes on which STC ST01219SE is installed, a 
``change in product'' AMOC approval request is not necessary to comply 
with the requirements of 14 CFR 39.17. For all other AMOC requests, 
however, the operator must request approval for an AMOC in accordance 
with the procedures specified in paragraph (n) of this AD.

Request To Add New Requirements

    Boeing asked that we add a new paragraph (k) to the NPRM (77 FR 
50407, August 21, 2012) titled ``New Inspections and Corrective Actions 
to Ensure Cross Beam Reinforcement,'' and suggested language for that 
new requirement. Boeing stated that the intent of the NPRM and Boeing 
Alert Service Bulletin 737-52A1100, Revision 5, dated February 14, 
2011, is to ensure that all forward cargo doors have the reinforcing 
modifications installed on both the beam and the frame at the forward 
and aft lower corners of the door. Boeing added that the current 
language in the NPRM and this service information leave open the 
potential that some doors might not have the reinforcing modification 
on the aft end of the cross beam, even though the doors were modified 
as specified in Boeing Service Bulletin 737-52-1100, dated August 25, 
1988, or Revision 1, dated July 20, 1989; or in accordance with the 
requirements of AD 90-06-02, Amendment 39-6489 (55 FR 8372, March 7, 
1990).
    We do not agree with the commenter's request to add a new 
requirement to this AD. Boeing Service Bulletin 737-52-1100, dated 
August 25, 1988; and Revision 1, dated July 20, 1989; includes 
modifications of the forward corner of the door frame and forward end 
of the lower cross beam, but no modifications of the aft end of the 
door. Modifications of the aft corner of the door frame and aft end of 
the lower cross beam were added in Boeing Service Bulletin 737-52-1100, 
Revision 2, dated March 31, 1994. Boeing Service Bulletin 737-52-1100, 
Revision 2, dated March 31, 1994, was required by paragraph (c) of AD 
2000-07-06, Amendment 39-11660 (65 FR 19302, April 11, 2000), as 
terminating action for the repetitive inspections. Paragraph (c) of AD 
2000-07-06 is restated in paragraph (i) of this AD, and addresses 
airplanes on which no modification was accomplished previously.
    The intent of paragraph (d) of AD 2000-07-06, Amendment 39-11660 
(65 FR 19302, April 11, 2000), which is restated in paragraph (j) of 
this AD, was to address airplanes on which a

[[Page 31391]]

modification was previously accomplished in accordance with Boeing 
Service Bulletin 737-52-1100, dated August 25, 1988; or Revision 1, 
dated July 20, 1989; and to ensure that both the forward and aft ends 
of the lower beam of the door were modified, as well as the forward and 
aft corners of the door frame. Therefore, Boeing Service Bulletin 737-
52-1100, Revision 2, dated March 31, 1994, was required by AD 2000-07-
06 for those modifications. However, paragraph (d) of AD 2000-07-06 and 
paragraph (j) of this AD do not specify modifying the aft end of the 
lower beam.
    We have made no change to the AD in regard to Boeing's request. 
However, we are considering proposing additional rulemaking in the near 
future to address this issue.

Explanation of Change to Final Rule

    We have changed paragraph (g) of this final rule to specify 
performing the inspection in accordance with Boeing 737 Nondestructive 
Test (NDT) Manual, D6-37239, Part 6, Section 51-00-00, Procedure 4 or 
Procedure 23, Revision 108, dated November 15, 2012, as applicable. The 
subject procedures were referred to as figures in the NPRM (77 FR 
50407, August 21, 2012). Because of a publishing system change in this 
revision of the NDT manual, the term ``figure'' was changed to 
``procedure.'' The technical instructions in the NDT manual were not 
changed.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
the AD with the change described previously. We also determined that 
this change will not increase the economic burden on any operator or 
increase the scope of the AD.

Costs of Compliance

    We estimate that this AD affects 581 airplanes of U.S. registry.
    We estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
              Action                    Labor cost        Parts cost      Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Inspections retained from AD 2000- 1 work-hour x $85                $0  $85 per inspection   $49,385 per
 07-06, Amendment 39-11660 (65 FR   per hour = $85 per                   cycle.               inspection cycle.
 19302, April 11, 2000).            inspection cycle.
Modification retained from AD      18 work-hours x $85          $1,865  $3,395.............  $1,972,495.
 2000-07-06.                        per hour = $1,530.
Inspections, new action..........  9 work-hours x $85               $0  $765...............  $444,465.
                                    per hour = $765.
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary modifications 
that would be required based on the results of the inspections. We have 
no way of determining the number of aircraft that might need these 
modifications:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Modification..................................  84 work-hours x $85 per hour =           $12,395         $19,535
                                                 $7,140.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition repairs/replacements specified in 
this 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 AD will not have federalism 
implications under Executive Order 13132. This AD will 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 this AD:
    (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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:


[[Page 31392]]


    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) 
2000-07-06, Amendment 39-11660 (65 FR 19302, April 11, 2000), and 
adding the following new AD:

2013-09-10 The Boeing Company: Amendment 39-17452; Docket No. FAA-
2012-0855; Directorate Identifier 2011-NM-136-AD.

(a) Effective Date

    This AD is effective June 28, 2013.

(b) Affected ADs

    This AD supersedes AD 2000-07-06, Amendment 39-11660 (65 FR 
19302, April 11, 2000).

(c) Applicability

    (1) This AD applies to all The Boeing Company Model 737-100, -
200, -200C, -300, -400, and -500 series airplanes, certificated in 
any category.
    (2) Installation of Supplemental Type Certificate (STC) 
ST01219SE (http://rgl.faa.gov/regulatory_and_guidance_library/rgstc.nsf/0/2C6E3DBDDD36F91C862576A4005D64E2?OpenDocument&Highlight=st01219se) 
does not affect the ability to accomplish the actions required by 
this AD. Therefore, for airplanes on which STC ST01219SE is 
installed, a ``change in product'' alternative method of compliance 
(AMOC) approval request is not necessary to comply with the 
requirements of 14 CFR 39.17.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 52, Doors.

(e) Unsafe Condition

    This AD was prompted by additional reports of fatigue cracking 
in the radius of the lower frames and in the lower number 5 cross 
beam of the forward cargo door. We are issuing this AD to prevent 
fatigue cracking of the lower corners of the door frame and number 5 
cross beam of the forward cargo door, which could result in rapid 
depressurization of the airplane.

(f) Compliance

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

(g) Retained High Frequency Eddy Current (HFEC) Initial/Repetitive 
Inspections

    This paragraph restates the requirements of paragraph (a) of AD 
2000-07-06, Amendment 39-11660 (65 FR 19302, April 11, 2000), with 
revised service information. Within 1 year or 4,500 flight cycles 
after May 16, 2000 (the effective date of AD 2000-07-06), whichever 
occurs later, perform an HFEC inspection to detect cracking of the 
lower corners (forward and aft) of the door frame of the forward 
cargo door, in accordance with Figure 4 or Figure 23, of Section 51-
00-00, of Part 6, of Boeing 737 Nondestructive Test (NDT) Manual, 
D6-37239, dated August 5, 1997, as applicable; or Procedure 4 or 
Procedure 23, of Section 51-00-00, of Part 6, of Boeing 737 
Nondestructive Test (NDT) Manual, D6-37239, Revision 108, dated 
November 15, 2012; as applicable.

    Note 1 to paragraphs (g), (h), (i), and (j) of this AD: 
Accomplishment of Boeing Service Bulletin 737-52-1100, Revision 2, 
dated March 31, 1994, does not supersede the requirements of AD 90-
06-02, Amendment 39-6489 (55 FR 8372, March 7, 1990).

    (1) If no cracking is detected, repeat the HFEC inspection 
thereafter at intervals not to exceed 4,500 flight cycles, until the 
requirements of paragraph (i) of this AD have been accomplished.
    (2) If any cracking is detected during any inspection required 
by paragraph (g) of this AD, prior to further flight, accomplish the 
requirements of paragraphs (g)(2)(i) and (g)(2)(ii) of this AD, 
which constitute terminating action for the repetitive inspections 
required by paragraph (g)(1) of this AD.
    (i) Accomplish the requirements of paragraph (g)(2)(i)(A) or 
(g)(2)(i)(B) of this AD, and install a cross beam repair and 
reinforcement modification of the cross beam, in accordance with 
Boeing Service Bulletin 737-52-1100, Revision 2, dated March 31, 
1994.
    (A) Repair the door frame of the forward cargo door in 
accordance with a method approved by the Manager, Seattle Aircraft 
Certification Office (ACO), Transport Airplane Directorate, FAA; or 
in accordance with data meeting the type certification basis of the 
airplane approved by the Boeing Commercial Airplanes Organization 
Designation Authorization (ODA) that has been authorized by the 
Manager, Seattle ACO, to make such findings. For a repair or 
modification method to be approved by the Manager, Seattle ACO, as 
required by this paragraph, and paragraphs (g)(2)(ii), (h)(2), 
(h)(3)(ii), and (i)(2) of this AD, the Manager's approval letter 
must specifically reference this AD.
    (B) Replace the door frame of the forward cargo door with a new 
door frame, in accordance with Boeing Service Bulletin 737-52-1100, 
Revision 2, dated March 31, 1994.
    (ii) Modify the repaired or replaced door frame of the forward 
cargo door, in accordance with a method approved by the Manager, 
Seattle ACO, or in accordance with data meeting the type 
certification basis of the airplane approved by the Boeing 
Commercial Airplanes ODA that has been authorized by the Manager, 
Seattle ACO, to make those findings.

(h) Retained Initial Detailed Inspection and Repetitive Inspections

    This paragraph restates the requirements of paragraph (b) of AD 
2000-07-06, Amendment 39-11660 (65 FR 19302, April 11, 2000). Within 
1 year or 4,500 flight cycles after May 16, 2000 (the effective date 
of AD 2000-07-06), whichever occurs later, perform a detailed 
inspection to detect cracking of the cross beam (i.e., upper and 
lower chord and web sections) of the forward cargo door, in 
accordance with Boeing Service Bulletin 737-52-1100, Revision 2, 
dated March 31, 1994. For the purposes of this AD, a detailed 
inspection is: An intensive examination of a specific item, 
installation, or assembly to detect damage, failure, or 
irregularity. Available lighting is normally supplemented with a 
direct source of good lighting at an intensity deemed appropriate. 
Inspection aids such as mirror, magnifying lenses, etc., may be 
necessary. Surface cleaning and elaborate procedures may be 
required.
    (1) If no cracking is detected, repeat the inspection thereafter 
at intervals not to exceed 4,500 flight cycles until the 
requirements of paragraph (i) of this AD have been accomplished.
    (2) If any cracking is detected on the lower chord section of 
the cross beam during any inspection required by paragraph (h) of 
this AD, prior to further flight, repair in accordance with a method 
approved by the Manager, Seattle ACO, or in accordance with data 
meeting the type certification basis of the airplane approved by the 
Boeing Commercial Airplanes ODA that has been authorized by the 
Manager, Seattle ACO, to make those findings.
    (3) If any cracking is detected on any area excluding the lower 
chord section of the cross beam (i.e., upper chord and web section) 
during any inspection required by paragraph (h) of this AD, prior to 
further flight, accomplish the requirements of paragraph (h)(3)(i) 
or (h)(3)(ii) of this AD, as applicable, which constitutes 
terminating action for the repetitive inspections required by 
paragraph (h)(1) of this AD.
    (i) For airplanes with line numbers 1 through 1231 inclusive: 
Install a cross beam repair and preventative modification of the 
outboard radius of the lower corners (forward and aft) of the door 
frame, in accordance with Boeing Service Bulletin 737-52-1100, 
Revision 2, dated March 31, 1994.
    (ii) For airplanes with line numbers 1232 and subsequent: 
Install a cross beam repair and preventative modification of the 
outboard radius of the lower corners (forward and aft) of the door 
frame, in accordance with a method approved by the Manager, Seattle 
ACO, or in accordance with data meeting the type certification basis 
of the airplane approved by the Boeing Commercial Airplanes ODA that 
has been authorized by the Manager, Seattle ACO, to make those 
findings.

(i) Retained Terminating Action

    This paragraph restates the requirements of paragraph (c) of AD 
2000-07-06, Amendment 39-11660 (65 FR 19302, April 11, 2000), with 
revised service information. Within 4 years or 12,000 flight cycles 
after May 16, 2000 (the effective date of AD 2000-07-06), whichever 
occurs later: Install the preventative modification of the outboard 
radius of the lower corners (forward and aft) of the door frame and 
the reinforcement modification of the cross beam of the forward 
cargo door, in accordance with paragraph (i)(1) or (i)(2) of this 
AD, as applicable. Accomplishment of paragraph (i)(1) or (i)(2) of 
this AD, as applicable, constitutes terminating action for the 
repetitive inspections required by paragraphs (g)(1) and (h)(1) of 
this AD.

[[Page 31393]]

    (1) For airplanes with line numbers 1 through 1231 inclusive: 
Accomplish the preventative modification and the reinforcement 
modification, in accordance with Boeing Service Bulletin 737-52-
1100, Revision 2, dated March 31, 1994.
    (2) For airplanes with line numbers 1232 and subsequent: 
Accomplish the preventative modification and the reinforcement 
modification, in accordance with a method approved by the Manager, 
Seattle ACO, or in accordance with data meeting the type 
certification basis of the airplane approved by the Boeing 
Commercial Airplanes ODA that has been authorized by the Manager, 
Seattle ACO, to make those findings; or in accordance with Boeing 
Alert Service Bulletin 737-52A1100, Revision 5, dated February 14, 
2011. As of the effective date of this AD, use only Boeing Alert 
Service Bulletin 737-52A1100, Revision 5, dated February 14, 2011, 
to accomplish the modifications required by this paragraph.

(j) Retained Action for Airplanes on Which Modifications Were 
Accomplished Previously

    This paragraph restates the requirements of paragraph (d) of AD 
2000-07-06, Amendment 39-11660 (65 FR 19302, April 11, 2000). For 
all airplanes on which modifications of the forward lower corner of 
the door frame and the cross beam of the forward cargo door were 
accomplished as specified in Boeing Service Bulletin 737-52-1100, 
dated August 25, 1988, or Revision 1, dated July 20, 1989; or in 
accordance with the requirements of AD 90-06-02, Amendment 39-6489 
(55 FR 8372, March 7, 1990): Within 4 years or 12,000 flight cycles 
after May 16, 2000 (the effective date of AD 2000-07-06), whichever 
occurs later, install the reinforcement modification of the aft 
corner of the door frame of the forward cargo door, in accordance 
with Boeing Service Bulletin 737-52-1100, Revision 2, dated March 
31, 1994. Accomplishment of such modification constitutes 
terminating action for the repetitive inspections required by 
paragraphs (g)(1) and (h)(1) of this AD.

(k) New Inspections and Corrective Actions

    Except as provided by paragraphs (m)(1) and (m)(2) of this AD: 
At the applicable time specified in paragraph 1.E, ``Compliance,'' 
of Boeing Alert Service Bulletin 737-52A1100, Revision 5, dated 
February 14, 2011, do the inspections required by paragraphs (k)(1) 
and (k)(2) of this AD, as applicable. Do all applicable related 
investigative and corrective actions before further flight, in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 737-52A1100, Revision 5, dated February 14, 2011; 
except as required by paragraph (m)(3) of this AD. Accomplishment of 
the inspections required by paragraph (k) of this AD terminates the 
requirements of the repetitive inspections required by paragraphs 
(g)(1) and (h)(1) of this AD. If any cracking is found in the number 
4 cross beam, before further flight, repair in accordance with 
Boeing Special Attention Service Bulletin 737-52-1149, dated 
December 11, 2003.

    Note 2 to paragraph (k) of this AD:  Boeing Alert Service 
Bulletin 737-52A1100, Revision 5, dated February 14, 2011, refers to 
Boeing Special Attention Service Bulletin 737-52-1149, dated 
December 11, 2003, as an additional source of guidance for the 
inspection for cracks of the number 4 cross beam.

    (1) For airplanes identified in Tables 1 and 2 of paragraph 1.E, 
``Compliance,'' of Boeing Alert Service Bulletin 737-52A1100, 
Revision 5, dated February 14, 2011: Do a one-time HFEC inspection 
of the applicable location for cracks, in accordance with the Work 
Instructions, Part I, of Boeing Alert Service Bulletin 737-52A1100, 
Revision 5, dated February 14, 2011.
    (2) For airplanes identified in Table 3 of paragraph 1.E, 
``Compliance,'' of Boeing Alert Service Bulletin 737-52A1100, 
Revision 5, dated February 14, 2011: Do a one-time general visual 
inspection of the reinforcement angle for excessive shimming or 
fastener pull-up, in accordance with the Work Instructions, Part 
III, of Boeing Alert Service Bulletin 737-52A1100, Revision 5, dated 
February 14, 2011.

(l) No Supplemental Structural Inspections Required by This AD

    (1) The supplemental structural inspections specified in Table 4 
of paragraph 1.E., ``Compliance,'' and Part 5 of the Accomplishment 
Instructions, of Boeing Alert Service Bulletin 737-52A1100, Revision 
5, dated February 14, 2011, are not required by this AD.
    (2) The supplemental structural inspections specified in Table 4 
of paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
737-52A1100, Revision 5, dated February 14, 2011, may be used in 
support of compliance with section 121.1109(c)(2) or 129.109(b)(2) 
of the Federal Aviation Regulations (14 CFR 121.1109(c)(2) or 14 CFR 
129.109(b)(2)). The corresponding actions specified in the 
Accomplishment Instructions of Boeing Alert Service Bulletin 737-
52A1100, Revision 5, dated February 14, 2011, are not required by 
this AD.

(m) Exceptions to Certain Service Information

    (1) Where paragraph 1.E., ``Compliance,'' of Boeing Alert 
Service Bulletin 737-52A1100, Revision 5, dated February 14, 2011, 
specifies a compliance time relative to the Revision 5 issue date of 
that service bulletin, this AD requires compliance within the 
specified compliance time after the effective date of this AD.
    (2) Where Table 1, ``Condition'' column of Paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-52A1100, 
Revision 5, dated February 14, 2011, specifies ``airplanes without 
either the repair or modification accomplished in accordance with 
previous releases of this service bulletin,'' the corresponding 
condition in this AD is for ``airplanes on which either a repair or 
modification was not accomplished before the effective date of this 
AD.''
    (3) Where Boeing Alert Service Bulletin 737-52A1100, Revision 5, 
dated February 14, 2011, specifies to contact Boeing for certain 
actions: Before further flight, do the repair using a method 
approved in accordance with the procedures specified in paragraph 
(n)(1) of this AD.

(n) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle ACO, 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 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 2000-07-06, 
Amendment 39-11660 (65 FR 19302, April 11, 2000), are approved as 
AMOCs for the corresponding requirements of this AD.

(o) Related Information

    (1) For more information about this AD, contact Alan Pohl, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle ACO, 
1601 Lind Avenue SW., Renton, Washington 98057-3356; phone (425) 
917-6450; fax (425) 917-6590; email alan.pohl@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.

(p) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (3) The following service information was approved for IBR on 
June 28, 2013.
    (i) Procedure 4, ``Surface Inspection of Aluminum Parts (Meter 
Display),'' of Section 51-00-00, of Part 6, ``Eddy Current,'' of 
Boeing 737 Nondestructive Test (NDT) Manual, D6-37239, Revision 108, 
dated November 15, 2012. The revision level of this document is 
identified only in the letter of transmittal; no other page of this 
document contains this information.

[[Page 31394]]

    (ii) Procedure 23, ``Aluminum Part Surface Inspection (Impedance 
Plane Display),'' Section 51-00-00, of Part 6, ``Eddy Current,'' of 
Boeing 737 Nondestructive Test (NDT) Manual, D6-37239, Revision 108, 
dated November 15, 2012. The revision level of this document is 
identified only in the letter of transmittal; no other page of this 
document contains this information.
    (iii) Boeing Alert Service Bulletin 737-52A1100, Revision 5, 
dated February 14, 2011.
    (iv) Boeing Special Attention Service Bulletin 737-52-1149, 
dated December 11, 2003.
    (4) The following service information was approved for IBR on 
May 16, 2000 (65 FR 19302, April 11, 2000).
    (i) Figure 4, of Section 51-00-00, of Part 6, of Boeing 737 
Nondestructive Test (NDT) Manual, D6-37239, dated August 5, 1997. 
The revision level is not specified on the title page or list of 
effective pages of this document. The title page of this document is 
not dated. Pages 1 and 2 of the list of effective pages of this 
document are dated August 5, 1997; page 2A is dated February 5, 
1997.
    (ii) Figure 23, of Section 51-00-00, of Part 6, of Boeing 737 
Nondestructive Test (NDT) Manual, D6-37239, dated August 5, 1997. 
The revision level is not specified on the title page or list of 
effective pages of this document. The title page of this document is 
not dated. Pages 1 and 2 of the list of effective pages of this 
document are dated August 5, 1997; page 2A is dated February 5, 
1997.
    (iii) Boeing Service Bulletin 737-52-1100, Revision 2, dated 
March 31, 1994.
    (5) For Boeing service information identified in this AD, 
contact Boeing Commercial Airplanes, Attention: Data & Services 
Management, P. O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; 
telephone 206-544-5000, extension 1; fax 206-766-5680; Internet 
https://www.myboeingfleet.com.
    (6) You may view this service information at FAA, 1601 Lind 
Avenue SW., Renton, Washington 98057-3356. For information on the 
availability of this material at the FAA, call 425-227-1221.
    (7) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Renton, Washington, on April 26, 2013.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-10797 Filed 5-23-13; 8:45 am]
BILLING CODE 4910-13-P


