```

[Federal Register Volume 78, Number 90 (Thursday, May 9, 2013)]
[Rules and Regulations]
[Pages 27020-27025]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-09113]

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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-1316; Directorate Identifier 2012-NM-186-AD; 
Amendment 39-17429; AD 2012-18-13 R1]
RIN 2120-AA64

Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: We are revising an existing airworthiness directive (AD) for 
all The Boeing Company Model 737-100, -200, -200C, -300, -400, and -500 
series

[[Page 27021]]

airplanes. That AD currently requires repetitive inspections to detect 
cracking in the web of the aft pressure bulkhead at body station 1016 
at the aft fastener row attachment to the ``Y'' chord, various 
inspections for discrepancies at the aft pressure bulkhead, and related 
investigative and corrective actions if necessary. This new AD requires 
clarifying certain actions specified in the existing AD. This AD was 
prompted by several reports of fatigue cracks in the aft pressure 
bulkhead. We are issuing this AD to detect and correct such fatigue 
cracking, which could result in rapid decompression of the fuselage.

DATES: This AD is effective June 13, 2013.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of October 24, 
2012 (77 FR 57990, September 19, 2012).
    The Director of the Federal Register approved the incorporation by 
reference of certain other publications listed in this AD as of May 10, 
1999 (64 FR 19879, April 23, 1999).

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 revise AD 2012-18-13, Amendment 39-17190 (77 FR 57990, 
September 19, 2012). That AD applies to all The Boeing Company Model 
737-100, -200, -200C, -300, -400, and -500 series airplanes. (AD 2012-
18-13 superseded AD 99-08-23, Amendment 39-11132 (64 FR 19879, April 
23, 1999)). The NPRM published in the Federal Register on January 9, 
2013 (78 FR 1772). That NPRM proposed to continue to require repetitive 
inspections to detect cracking in the web of the aft pressure bulkhead 
at body station 1016 at the aft fastener row attachment to the ``Y'' 
chord, various inspections for discrepancies at the aft pressure 
bulkhead, and related investigative and corrective actions if 
necessary. That NPRM also proposed to clarify certain actions specified 
in the existing AD.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the proposal 
(78 FR 1772, January 9, 2013) and the FAA's response to each comment.

Supportive Comment

    The Boeing Company stated that it supports the NPRM (78 FR 1772, 
January 9, 2013).

Supplemental Type Certificate (STC) Comment

    Aviation Partners Boeing stated that the installation of winglets 
per STC ST01219SE (http://rgl.faa.gov/Regulatory--and--Guidance--
Library/rgstc.nsf/0/2c6e3dbddd36f91c862576a4005d64e2/$FILE/
ST01219SE.pdf) does not affect the accomplishment of the manufacturer's 
service instructions.
    We have added paragraph (c)(2) of this AD to state that 
installation of STC ST01219SE (http://rgl.faa.gov/Regulatory--and--
Guidance--Library/rgstc.nsf/0/2c6e3dbddd36f91c862576a4005d64e2/$FILE/
ST01219SE.pdf) 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.

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-and minor editorial 
changes. We have determined that these minor changes:
     Are consistent with the intent that was proposed in the 
NPRM (78 FR 1772, January 9, 2013) for correcting the unsafe condition; 
and
     Do not add any additional burden upon the public than was 
already proposed in the NPRM (78 FR 1772, January 9, 2013).
    We also determined that these changes 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 566 airplanes of U.S. registry.

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                               Parts                             Cost on U.S.
              Action                       Labor cost           cost     Cost per product         operators
----------------------------------------------------------------------------------------------------------------
Low frequency eddy current (LFEC)  8 work-hours x $85 per          $0  $680................  $384,880.
 inspection [retained action from   hour = $680.
 AD 99-08-23, Amendment 39-11132
 (64 FR 19879, April 23, 1999)].
Detailed visual inspection         2 work-hours x $85 per           0  $170................  $96,220.
 [retained action from AD           hour = $170.
 99[dash]08-23, Amendment 39-
 11132 (64 FR 19879, April 23,
 1999)].

[[Page 27022]]

 
Detailed, high frequency eddy      Up to 60 work-hours x $85        0  Up to $5,100 per      Up to $2,886,600
 current (HFEC), and LFEC           per hour = $5,100 per               inspection cycle.     per inspection
 inspections of the web at the      inspection cycle.                                         cycle.
 ``Y'' chord of the bulkhead, the
 web located under the outer
 circumferential tear strap, the
 ``Z'' stiffeners at the dome
 cap, and existing repairs
 [retained actions from AD 2012-
 18-13, Amendment 39-17190 (77 FR
 57990, September 19, 2012)].
----------------------------------------------------------------------------------------------------------------

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

                                               On-condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                       Cost per
                    Action                                    Labor cost                 Parts cost    product
----------------------------------------------------------------------------------------------------------------
Detailed and HFEC inspections for oil-canning.  1 work-hour x $85 per hour = $85......           $0          $85
LFEC or HFEC inspection for cracking..........  2 work-hours x $85 per hour = $170....            0          170
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
cost estimates for the crack repairs 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 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:

    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) 
2012-18-13, Amendment 39-17190 (77 FR 57990, September 19, 2012), and 
adding the following new AD:

2012-18-13 R1 The Boeing Company: Amendment 39-17429; Docket No. 
FAA-2012-1316; Directorate Identifier 2012-NM-186-AD.

(a) Effective Date

    This AD is effective June 13, 2013.

(b) Affected ADs

    This AD revises AD 2012-18-13, Amendment 39-17190 (77 FR 57990, 
September 19, 2012).

(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/$FILE/ST01219SE.pdf) 
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 53, Fuselage.

(e) Unsafe Condition

    This AD was prompted by several reports of fatigue cracks in the 
aft pressure bulkhead. We are issuing this AD to detect and correct

[[Page 27023]]

such fatigue cracking, which could result in rapid decompression of 
the fuselage.

(f) Compliance

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

(g) Retained Initial Inspection

    This paragraph restates the initial inspection required by 
paragraph (g) of AD 2012-18-13, Amendment 39-17190 (77 FR 57990, 
September 19, 2012). Perform either inspection specified by 
paragraph (g)(1) or (g)(2) of this AD at the time specified in 
paragraph (h) of this AD.
    (1) Perform a low frequency eddy current (LFEC) inspection from 
the aft side of the aft pressure bulkhead to detect discrepancies 
(including cracking, misdrilled fastener holes, and corrosion) of 
the web of the upper section of the aft pressure bulkhead at body 
station 1016 at the aft fastener row attachment to the ``Y'' chord, 
from stringer 15 left (S-15L) to stringer 15 right (S-15R), in 
accordance with Boeing 737 Nondestructive Test Manual D6-37239, Part 
6, Section 53-10-54, dated December 5, 1998.
    (2) Perform a detailed visual inspection of the aft fastener row 
attachment to the ``Y'' chord from the forward side of the aft 
pressure bulkhead to detect discrepancies (including cracking, 
misdrilled fastener holes, and corrosion) of the entire web of the 
aft pressure bulkhead at body station 1016.

(h) Retained Compliance Times

    This paragraph restates the compliance times specified in 
paragraph (h) of AD 2012-18-13, Amendment 39-17190 (77 FR 57990, 
September 19, 2012). Perform the inspection required by paragraph 
(g) of this AD at the time specified in paragraph (h)(1), (h)(2), or 
(h)(3) of this AD, as applicable.
    (1) For airplanes that have accumulated 40,000 or more total 
flight cycles as of May 10, 1999 (the effective date of AD 99-08-23, 
Amendment 39-11132 (64 FR 19879, April 23, 1999)): Inspect within 
375 flight cycles or 60 days after May 10, 1999 (the effective date 
of AD 99-08-23), whichever occurs later.
    (2) For airplanes that have accumulated 25,000 or more total 
flight cycles and fewer than 40,000 total flight cycles as of May 
10, 1999 (the effective date of AD 99-08-23, Amendment 39-11132 (64 
FR 19879, April 23, 1999)): Inspect within 750 flight cycles or 90 
days after May 10, 1999 (the effective date of AD 99-08-23), 
whichever occurs later.
    (3) For airplanes that have accumulated fewer than 25,000 total 
flight cycles as of May 10, 1999 (the effective date of AD 99-08-23, 
Amendment 39-11132 (64 FR 19879, April 23, 1999)): Inspect prior to 
the accumulation of 25,750 total flight cycles.

(i) Retained Repetitive Inspections

    This paragraph restates the repetitive inspections required by 
paragraph (i) of AD 2012-18-13, Amendment 39-17190 (77 FR 57990, 
September 19, 2012). Within 1,200 flight cycles after performing the 
initial inspection required by paragraph (g) of this AD, and 
thereafter at intervals not to exceed 1,200 flight cycles: Perform 
either inspection specified by paragraph (g)(1) or (g)(2) of this 
AD.

(j) Retained Corrective Actions

    This paragraph restates the corrective actions required by 
paragraph (j) of AD 2012-18-13, Amendment 39-17190 (77 FR 57990, 
September 19, 2012). If any discrepancy is detected during any 
inspection required by paragraph (g), (h), or (i) of this AD: Prior 
to further flight, accomplish the actions specified by paragraphs 
(j)(1) and (j)(3) of this AD, and paragraph (j)(2) of this AD, if 
applicable.
    (1) Perform a high frequency eddy current inspection from the 
forward side of the bulkhead to detect cracking of the web at the 
``Y'' chord attachment, around the entire periphery of the ``Y'' 
chord, in accordance with Boeing 737 Nondestructive Test Manual D6-
37239, Part 6, Section 51-00-00, Figure 23, dated November 5, 1995.
    (2) If the most recent inspection performed in accordance with 
paragraph (g) of this AD was not a detailed visual inspection: 
Accomplish the actions specified by paragraph (g)(2) of this AD. If 
the inspection was a detailed visual inspection, it is not necessary 
to repeat that inspection prior to further flight.
    (3) Repair any discrepancy such as cracking or corrosion or 
misdrilled fastener holes using a method approved in accordance with 
the procedures specified in paragraph (u) of this AD.

(k) Retained Inspections of the Web at the ``Y'' Chord Upper Bulkhead 
From S-15L to S-15R

    This paragraph restates the inspections of the web at the ``Y'' 
chord upper bulkhead from S-15L to S-15R required by paragraph (k) 
of AD 2012-18-13, Amendment 39-17190 (77 FR 57990, September 19, 
2012). At the later of the times specified in paragraphs (k)(1) and 
(k)(2) of this AD: Do detailed and LFEC inspections of the aft side 
of the bulkhead web, or do detailed and high frequency eddy current 
(HFEC) inspections from the forward side of the bulkhead, and do all 
applicable related investigative and corrective actions; in 
accordance with Part 1 of the Accomplishment Instructions of Boeing 
Alert Service Bulletin 737-53A1214, Revision 4, dated December 16, 
2011, except as required by paragraphs (r)(1) and (r)(3) of this AD. 
Inspect for cracks, incorrectly drilled fastener holes, and 
elongated fastener holes. Do all applicable related investigative 
and corrective actions before further flight. Repeat the inspections 
at the applicable times specified in table 1 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-53A1214, 
Revision 4, dated December 16, 2011.
    (1) Prior to the accumulation of 25,000 total flight cycles.
    (2) Except as required by paragraphs (r)(2) and (r)(4) of this 
AD, at the later of the times specified in the ``Compliance Time'' 
column in table 1 of paragraph 1.E., ``Compliance,'' of Boeing Alert 
Service Bulletin 737-53A1214, Revision 4, dated December 16, 2011.

(l) Retained Inspections of the Web at the ``Y'' Chord in the Lower 
Bulkhead From S-15L to S-15R With Revised Inspection and Repair 
Conditions

    This paragraph restates the inspections of the web at the ``Y'' 
chord in the lower bulkhead from S-15L to S-15R required by 
paragraph (l) of AD 2012-18-13, Amendment 39-17190 (77 FR 57990, 
September 19, 2012), with revised inspection and repair conditions. 
Except as required by paragraphs (r)(2) and (r)(5) of this AD, at 
the applicable time specified in table 2 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-53A1214, 
Revision 4, dated December 16, 2011: Do detailed and eddy current 
inspections of the web from the forward or aft side of the bulkhead 
for cracks, incorrectly drilled fastener holes, and elongated 
fastener holes, in accordance with Part III of the Accomplishment 
Instructions of Boeing Alert Service Bulletin 737-53A1214, Revision 
4, dated December 16, 2011, except as required by paragraphs (r)(1) 
and (r)(3) of this AD. If any crack, incorrectly drilled fastener 
hole, elongated fastener hole, or corrosion is found, before further 
flight, repair using a method approved in accordance with the 
procedures specified in paragraph (u) of this AD. Repeat the 
inspections at the applicable times specified in table 2 of 
paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
737-53A1214, Revision 4, dated December 16, 2011.

(m) Retained One-Time Inspection Under the Tear Strap

    This paragraph restates the one-time inspection under the tear 
strap required by paragraph (m) of AD 2012-18-13, Amendment 39-17190 
(77 FR 57990, September 19, 2012). Except as required by paragraphs 
(r)(2) and (r)(5) of this AD, at the applicable time specified in 
table 3 of paragraph 1.E., ``Compliance,'' of Boeing Alert Service 
Bulletin 737-53A1214, Revision 4, dated December 16, 2011: Do a one-
time LFEC inspection for cracks on the aft side of the bulkhead of 
the web located under the outer circumferential tear strap, or do a 
one-time HFEC inspection for cracks from the forward side of the 
bulkhead of the web located under the outer circumferential tear 
strap, in accordance with Part II of the Accomplishment Instructions 
of Boeing Alert Service Bulletin 737-53A1214, Revision 4, dated 
December 16, 2011, except as required by paragraph (r)(1) of this 
AD. If any cracking is found, before further flight, repair the 
bulkhead using a method approved in accordance with the procedures 
specified in paragraph (u) of this AD.

(n) Retained Inspection for Oil-Canning

    This paragraph restates the inspection for oil-canning required 
by paragraph (n) of AD 2012-18-13, Amendment 39-17190 (77 FR 57990, 
September 19, 2012). Except as required by paragraph (r)(2) of this 
AD, at the applicable time specified in table 4 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-53A1214, 
Revision 4, dated December 16, 2011: Do a detailed inspection from 
the aft side of the bulkhead for oil-canning and do all

[[Page 27024]]

applicable related investigative and corrective actions, in 
accordance with Part II of the Accomplishment Instructions of Boeing 
Alert Service Bulletin 737-53A1214, Revision 4, dated December 16, 
2011, except as required by paragraph (r)(1) of this AD. Do all 
related investigative and corrective actions before further flight. 
Thereafter, repeat the inspection at the applicable times specified 
in table 4 of paragraph 1.E., ``Compliance,'' of Boeing Alert 
Service Bulletin 737-53A1214, Revision 4, dated December 16, 2011. 
For oil-cans found within the limits specified in Part II of the 
Accomplishment Instructions of Boeing Alert Service Bulletin 737-
53A1214, Revision 4, dated December 16, 2011: In lieu of installing 
the repair before further flight, at the applicable times specified 
in table 4 of paragraph 1.E., ``Compliance,'' of Boeing Alert 
Service Bulletin 737-53A1214, Revision 4, dated December 16, 2011, 
do initial and repetitive detailed and HFEC inspections for cracks 
of the oil-canning and install the repair, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 737-
53A1214, Revision 4, dated December 16, 2011. If any crack is found, 
before further flight, repair the cracking using a method approved 
in accordance with the procedures specified in paragraph (u) of this 
AD. Installing the repair terminates the repetitive inspections for 
cracks.

(o) Retained Inspection of the Dome Cap at the Center of the Bulkhead

    This paragraph restates the inspection of the dome cap at the 
center of the bulkhead required by paragraph (o) of AD 2012-18-13, 
Amendment 39-17190 (77 FR 57990, September 19, 2012). Except as 
required by paragraphs (r)(2) and (r)(5) of this AD, at the 
applicable time specified in table 5 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-53A1214, 
Revision 4, dated December 16, 2011: Do an eddy current inspection 
to detect any cracking of the dome cap at the center of the 
bulkhead, and do all applicable corrective actions, in accordance 
with Part IV of the Accomplishment Instructions of Boeing Alert 
Service Bulletin 737-53A1214, Revision 4, dated December 16, 2011. 
Do all corrective actions before further flight. Repeat the 
inspection at the times specified in table 5 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-53A1214, 
Revision 4, dated December 16, 2011.

(p) Retained Inspection of the Forward Flange of the ``Z'' Stiffeners 
at the Dome Cap

    This paragraph restates the inspection of the forward flange of 
the ``Z'' stiffeners at the dome cap required by paragraph (p) of AD 
2012-18-13, Amendment 39-17190 (77 FR 57990, September 19, 2012). 
Except as required by paragraphs (r)(2) and (r)(5) of this AD, at 
the applicable time specified in table 6 of paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-53A1214, 
Revision 4, dated December 16, 2011: Do an HFEC inspection to detect 
any cracking of the ``Z'' stiffener flanges at the dome cap in the 
center of the bulkhead, in accordance with Part V of the 
Accomplishment Instructions of Boeing Alert Service Bulletin 737-
53A1214, Revision 4, dated December 16, 2011, except as required by 
paragraph (r)(1) of this AD. If any crack is found, before further 
flight, repair the flanges using a method approved in accordance 
with the procedures specified in paragraph (u) of this AD. Repeat 
the inspection at the applicable times specified in table 6 of 
paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
737-53A1214, Revision 4, dated December 16, 2011.

(q) Retained Inspection for Existing Repairs on the Bulkhead

    This paragraph restates the inspection for existing repairs on 
the bulkhead required by paragraph (q) of AD 2012-18-13, Amendment 
39-17190 (77 FR 57990, September 19, 2012). Except as required by 
paragraph (r)(2) of this AD, at the applicable time specified in 
table 7 of paragraph 1.E., ``Compliance,'' of Boeing Alert Service 
Bulletin 737-53A1214, Revision 4, dated December 16, 2011: Do a 
detailed inspection of the bulkhead web and stiffeners for existing 
repairs, in accordance with Part VI of the Accomplishment 
Instructions of Boeing Alert Service Bulletin 737-53A1214, Revision 
4, dated December 16, 2011, except as required by paragraph (r)(1) 
of this AD.
    (1) If any repair identified in the ``Condition'' column of 
table 8 of paragraph 1.E., ``Compliance,'' of Boeing Alert Service 
Bulletin 737-53A1214, Revision 4, dated December 16, 2011, is found 
and the ``Reference'' column refers to Appendix A, B, C, or D of 
that service bulletin: At the applicable times specified in table 8 
of paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
737-53A1214, Revision 4, dated December 16, 2011, except as required 
by paragraph (r)(2) of this AD, do an HFEC inspection or an LFEC 
inspection of the web for cracking, in accordance with Appendix A, 
B, C, or D, as applicable, of Boeing Alert Service Bulletin 737-
53A1214, Revision 4, dated December 16, 2011. If any cracking is 
found, before further flight, repair using a method approved in 
accordance with the procedures specified in paragraph (u) of this 
AD. Repeat the inspections thereafter at the applicable intervals 
specified in table 8 of paragraph 1.E., ``Compliance,'' of Boeing 
Alert Service Bulletin 737-53A1214, Revision 4, dated December 16, 
2011.
    (2) If any repair identified in the ``Condition'' column of 
table 8 of paragraph 1.E., ``Compliance,'' of Boeing Alert Service 
Bulletin 737-53A1214, Revision 4, dated December 16, 2011, is found 
and the ``Reference'' column refers to Appendix E of that service 
bulletin: At the applicable times specified in table 8 of paragraph 
1.E., ``Compliance,'' of Boeing Alert Service Bulletin 737-53A1214, 
Revision 4, dated December 16, 2011, except as required by paragraph 
(r)(2) of this AD, remove the repair and replace with a new repair, 
in accordance with Appendix E of Boeing Alert Service Bulletin 737-
53A1214, Revision 4, dated December 16, 2011.
    (3) If any non-SRM (structural repair manual) repair is found 
and the repair does not have FAA-approved damage tolerance 
inspections: Except as required by paragraph (r)(2) of this AD, at 
the applicable time specified in table 7 of Paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 737-53A1214, 
Revision 4, dated December 16, 2011, contact the Boeing Commercial 
Airplanes Organization Designation Authorization (ODA) that has been 
authorized by the Manager, Seattle Aircraft Certification Office 
(ACO), for damage tolerance inspections. Do those damage tolerance 
inspections at the times given using a method approved in accordance 
with the procedures specified in paragraph (u) of this AD.

(r) Retained Exceptions to the Service Information

    This paragraph restates the exceptions to the service 
information required by paragraph (r) of AD 2012-18-13, Amendment 
39-17190 (77 FR 57990, September 19, 2012).
    (1) Where Boeing Alert Service Bulletin 737-53A1214, Revision 4, 
dated December 16, 2011, specifies to contact Boeing for repair 
instructions: Before further flight, repair using a method approved 
in accordance with the procedures specified in paragraph (u) of this 
AD.
    (2) Where Boeing Alert Service Bulletin 737-53A1214, Revision 4, 
dated December 16, 2011, specifies a compliance time ``after the 
date of Revision 1 to this service bulletin,'' ``from the date of 
Revision 3 of this service bulletin,'' ``after the date of Revision 
3 to this service bulletin,'' or ``of the effective date of AD 99-
08-23,'' this AD requires compliance within the specified compliance 
time after October 24, 2012 (the effective date of AD 2012-18-13, 
Amendment 39-17190 (77 FR 57990, September 19, 2012)).
    (3) Access and restoration procedures specified in the 
Accomplishment Instructions of Boeing Alert Service Bulletin 737-
53A1214, Revision 4, dated December 16, 2011, are not required by 
this AD. Operators may do those procedures following their 
maintenance practices.
    (4) Where table 1 of paragraph 1.E., ``Compliance,'' of Boeing 
Alert Service Bulletin 737-53A1214, Revision 4, dated December 16, 
2011, specifies a compliance time relative to actions done ``in 
accordance with paragraph (a)(2) of AD 99-08-23,'' this AD requires 
compliance within the specified compliance time relative to actions 
specified in paragraph (g)(2) of this AD.
    (5) Where the Condition columns in tables 2, 3, 5, and 6 of 
paragraph 1.E., ``Compliance,'' of Boeing Alert Service Bulletin 
737-53A1214, Revision 4, dated December 16, 2011, refer to total 
flight cycles, this AD applies to the airplanes with the specified 
total flight cycles as of October 24, 2012 (the effective date of AD 
2012-18-13, Amendment 39-17190 (77 FR 57990, September 19, 2012)).

(s) Retained Terminating Action With Revised Paragraph Reference

    This paragraph restates the terminating action specified in 
paragraph (s) of AD 2012-18-13, Amendment 39-17190 (77 FR 57990, 
September 19, 2012), with a revised paragraph reference. 
Accomplishment of the requirements in paragraph (k) of this AD 
terminates the requirements of paragraphs (g) through (j) of this 
AD.

[[Page 27025]]

(t) Credit for Previous Actions

    This paragraph restates the credit for previous actions 
specified by paragraph (t) of AD 2012-18-13, Amendment 39-17190 (77 
FR 57990, September 19, 2012). This paragraph provides credit for 
the actions required by paragraphs (k) through (s) of this AD, if 
the actions were performed before the effective date of this AD 
using the service bulletins specified in paragraphs (t)(1) through 
(t)(4) of this AD.
    (1) Boeing Alert Service Bulletin 737-53A1214, dated June 17, 
1999.
    (2) Boeing Alert Service Bulletin 737-53A1214, Revision 1, dated 
June 22, 2000.
    (3) Boeing Alert Service Bulletin 737-53A1214, Revision 2, dated 
May 24, 2001.
    (4) Boeing Alert Service Bulletin 737-53A1214, Revision 3, dated 
January 19, 2011.

(u) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle 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 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 99-08-23, 
Amendment 39-11132 (64 FR 19879, April 23, 1999), are approved as 
AMOCs for the corresponding provisions of this AD.
    (5) AMOCs approved previously in accordance with AD 2012-18-13, 
Amendment 39-17190 (77 FR 57990, September 19, 2012), are approved 
as AMOCs for the corresponding provisions of this AD.

(v) Related Information

    (1) For more information about this AD, contact Alan Pohl, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue SW., Renton, Washington 
98057-3356; phone: (425) 917-6440; 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.

 (w) 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 
October 24, 2012 (77 FR 57990, September 19, 2012).
    (i) Boeing Alert Service Bulletin 737-53A1214, Revision 4, dated 
December 16, 2011.
    (ii) Reserved.
    (4) The following service information was approved for IBR on 
May 10, 1999 (64 FR 19879, April 23, 1999).
    (i) Boeing 737 Nondestructive Test Manual D6-37239, Part 6, 
Section 53-10-54, dated December 5, 1998.
    (ii) Boeing 737 Nondestructive Test Manual D6-37239, Part 6, 
Section 51-00-00, Figure 23, dated November 5, 1995.
    (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, Washington 98124-
2207; telephone 206-544-5000, extension 1; fax 206-766-5680; 
Internet https://www.myboeingfleet.com.
    (6) 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.
    (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 5, 2013.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-09113 Filed 5-8-13; 8:45 am]
BILLING CODE 4910-13-P
```