Document ID: FAA-2015-2961-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: The Boeing Company Airplanes
Posted Date: 2015-07-24T04:00Z

[Federal Register Volume 80, Number 142 (Friday, July 24, 2015)]
[Proposed Rules]
[Pages 43974-43979]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-18152]

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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-2961; Directorate Identifier 2014-NM-145-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 Airworthiness Directive (AD) 2012-15-
13, which applies to certain The Boeing Company Model 747-100B SUD, 
747-300, 747-400, and 747-400D series airplanes; and Model 747-200B 
series airplanes having a stretched upper deck. AD 2012-15-13 currently 
requires inspections for cracking and discrepancies of certain 
fasteners; modification of the frame-to-tension-tie joints; repetitive 
post-modification inspections; related investigative and corrective 
actions if necessary; and repetitive inspections for cracking in the 
tension tie channels, and repair if necessary. For certain airplanes, 
AD 2012-15-13 also requires an inspection to determine if the angle is 
installed correctly, and re-installation if necessary; and an 
inspection at the fastener locations where the tension tie previously 
attached to the frame prior to certain modifications, and repair if 
necessary. Since we issued AD 2012-15-13, an evaluation indicated that 
the upper deck is subject to widespread fatigue damage (WFD). This 
proposed AD would add a new inspection for cracking in the tension tie 
channels and post-modification inspections of the modified tension ties 
for cracking, and repair if necessary. We are proposing this AD to 
prevent fatigue cracking of the tension ties, shear webs, and frames of 
the upper deck, which could result in rapid decompression and reduced 
structural integrity of the airplane.

DATES: We must receive comments on this proposed AD by September 8, 
2015.

ADDRESSES: You may send comments, using the procedures found in 14 CFR

[[Page 43975]]

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, WA 98124-2207; telephone 206-544-
5000, extension 1; fax 206-766-5680; Internet https://www.myboeingfleet.com. You may view this referenced service information 
at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., 
Renton, WA. For information on the availability of this material at the 
FAA, call 425-227-1221. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2015-
2961.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2015-
2961; 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: Bill Ashforth, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6432; fax: 
425-917-6590; email: bill.ashforth@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-2015-2961; 
Directorate Identifier 2014-NM-145-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 July 23, 2012, we issued AD 2012-15-13, Amendment 39-17142 (77 
FR 47267, August 8, 2012), for certain The Boeing Company Model 747-
100B SUD, 747-300, 747-400, and 747-400D series airplanes; and Model 
747-200B series airplanes having a stretched upper deck. AD 2012-15-13 
requires repetitive open hole high frequency eddy current (HFEC) 
inspections for cracking in the forward and aft tension tie channels, 
and repair if necessary. For certain airplanes, AD 2012-15-13 also 
requires a one-time angle inspection to determine if the angle is 
installed correctly, and re-installation if necessary; and a one-time 
open hole HFEC inspection at the fastener locations where the tension 
tie previously attached to the frame prior to certain modifications, 
and repair if necessary. AD 2012-15-13 resulted from reports of cracked 
and severed tension ties, broken fasteners, and cracks in the frame, 
shear web, and shear ties adjacent to tension ties for the upper deck. 
We issued AD 2012-15-13 to detect and correct cracking of the tension 
ties, shear webs, and frames of the upper deck, which could result in 
rapid decompression and reduced structural integrity of the airplane.

Widespread Fatigue Damage

    Structural fatigue damage is progressive. It begins as minute 
cracks, and those cracks grow under the action of repeated stresses. 
This can happen because of normal operational conditions and design 
attributes, or because of isolated situations or incidents such as 
material defects, poor fabrication quality, or corrosion pits, dings, 
or scratches. Fatigue damage can occur locally, in small areas or 
structural design details, or globally. Global fatigue damage is 
general degradation of large areas of structure with similar structural 
details and stress levels. Multiple-site damage is global damage that 
occurs in a large structural element such as a single rivet line of a 
lap splice joining two large skin panels. Global damage can also occur 
in multiple elements such as adjacent frames or stringers. Multiple-
site-damage and multiple-element-damage cracks are typically too small 
initially to be reliably detected with normal inspection methods. 
Without intervention, these cracks will grow, and eventually compromise 
the structural integrity of the airplane, in a condition known as 
widespread fatigue damage (WFD). As an airplane ages, WFD will likely 
occur, and will certainly occur if the airplane is operated long enough 
without any intervention.
    The FAA's WFD rule (75 FR 69746, November 15, 2010) became 
effective on January 14, 2011. The WFD rule requires certain actions to 
prevent structural failure due to WFD throughout the operational life 
of certain existing transport category airplanes and all of these 
airplanes that will be certificated in the future. For existing and 
future airplanes subject to the WFD rule, the rule requires that design 
approval holders (DAHs) establish a limit of validity (LOV) of the 
engineering data that support the structural maintenance program. 
Operators affected by the WFD rule may not fly an airplane beyond its 
LOV, unless an extended LOV is approved.
    The WFD rule (75 FR 69746, November 15, 2010) does not require 
identifying and developing maintenance actions if the DAHs can show 
that such actions are not necessary to prevent WFD before the airplane 
reaches the LOV. Many LOVs, however, do depend on accomplishment of 
future maintenance actions. As stated in the WFD rule, any maintenance 
actions necessary to reach the LOV will be mandated by airworthiness 
directives through separate rulemaking actions.
    In the context of WFD, this action is necessary to enable DAHs to 
propose LOVs that allow operators the longest operational lives for 
their airplanes, and still ensure that WFD will not occur. This 
approach allows for an implementation strategy that provides 
flexibility to DAHs in determining the timing of service information 
development (with FAA approval), while providing operators with 
certainty regarding the LOV applicable to their airplanes.

Actions Since AD 2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 
2012), Was Issued

    The preamble to AD 2012-15-13, Amendment 39-17142 (77 FR 47267, 
August 8, 2012), specified that we considered the requirements of that 
AD

[[Page 43976]]

``interim action.'' AD 2012-15-13 explained that we might consider 
further rulemaking if final action is later identified. Since we issued 
AD 2012-15-13, an evaluation by the DAH indicated that the upper deck 
is subject to WFD. We have determined that it is necessary to mandate a 
new inspection for cracking in the tension tie channels, repetitive 
post-modification inspections of the modified tension ties for 
cracking, and repair if necessary.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Alert Service Bulletin 747-53A2559, Revision 2, 
dated May 13, 2014. The service information describes procedures for 
modifying the tension tie and frame at certain center sections. This 
service information is reasonably available because the interested 
parties have access to it through their normal course of business or by 
the means identified in the ADDRESSES section of this NPRM.

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 of the requirements of AD 2012-
15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012). For certain 
airplanes, this proposed AD would mandate a new inspection for cracking 
in the forward and aft tension tie channels, repetitive post-
modification inspections of the modified tension ties for cracking, and 
repair if necessary. Refer to Boeing Alert Service Bulletin 747-
53A2559, Revision 2, dated May 13, 2014, for details on the procedures 
and compliance times.

Explanation of Compliance Time

    The compliance time for the modification specified in this proposed 
AD for addressing WFD was established to ensure that discrepant 
structure is modified before WFD develops in airplanes. Standard 
inspection techniques cannot be relied on to detect WFD before it 
becomes a hazard to flight. We will not grant any extensions of the 
compliance time to complete any AD-mandated service bulletin related to 
WFD without extensive new data that would substantiate and clearly 
warrant such an extension.

Costs of Compliance

    We estimate that this proposed AD affects 120 airplanes of U.S. 
registry.
    We estimate the following costs to comply with this proposed AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                            Cost per
            Action                   Labor cost          Parts cost         product       Cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
Retained modification in AD    Between 257 and 263    Between $341,334  Between          Between $24,332,993 and
 2012-15-13, Amendment 39-      work-hours = between   and $345,490.     $363,179 and     $24,645,615.
 17142 (77 FR 47267, August     $21,845 and $22,355.                     $367,845.
 8, 2012) (67 airplanes).
Retained                       6 work-hours x $85     $0..............  $510 per         $34,170 per inspection
 post[dash]modification         per hour = $510 per                      inspection       cycle.
 inspections in AD 2012-15-     inspection cycle.                        cycle.
 13, Amendment 39-17142 (77
 FR 47267, August 8, 2012)
 (67 airplanes).
New proposed inspection......  10 work-hours x $85    $0..............  $850...........  $102,000.
                                per hour = $850.
New proposed                   216 work-hours x $85   $0..............  $18,360 per      $2,203,200 per
 post[dash]modification eddy    per hour = $18,360                       inspection       inspection cycle.
 current inspections.           per inspection cycle.                    cycle.
----------------------------------------------------------------------------------------------------------------

    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.

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) 
2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012), and 
adding the following new AD:

[[Page 43977]]

The Boeing Company: Docket No. FAA-2015-2961; Directorate Identifier 
2014-NM-145-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by September 8, 
2015.

(b) Affected ADs

    This AD replaces AD 2012-15-13, Amendment 39-17142 (77 FR 47267, 
August 8, 2012).

(c) Applicability

    This AD applies to The Boeing Company Model 747-100B SUD, 747-
300, 747-400, and 747-400D series airplanes; and Model 747-200B 
series airplanes having a stretched upper deck; certificated in any 
category; excluding airplanes that have been converted to a large 
cargo freighter configuration.

(d) Subject

    Air Transport Association (ATA) of America Code 53, Fuselage.

(e) Unsafe Condition

    This AD was prompted by reports of cracked and severed tension 
ties, broken fasteners, and cracks in the frame, shear web, and 
shear ties adjacent to tension ties for the upper deck. This AD was 
also prompted by an evaluation by the design approval holder (DAH), 
which indicated that the upper deck is subject to widespread fatigue 
damage (WFD). We are issuing this AD to prevent fatigue cracking of 
the tension ties, shear webs, and frames of the upper deck, which 
could result in rapid decompression and reduced structural integrity 
of the airplane.

(f) Compliance

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

(g) Retained Repetitive Stage 1 Inspections, With No Changes

    This paragraph restates the requirements of paragraph (g) of AD 
2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012), with 
no changes. For all airplanes: Do detailed inspections for cracking 
or discrepancies of the fasteners in the tension ties, shear webs, 
and frames at body stations (STA) 1120 through 1220, and related 
investigative and corrective actions as applicable, by doing all 
actions specified in and in accordance with ``Stage 1 Inspection'' 
of the Accomplishment Instructions of Boeing Alert Service Bulletin 
747-53A2507, dated April 21, 2005, except as provided by paragraph 
(k) of this AD; or Boeing Alert Service Bulletin 747-53A2507, 
Revision 1, dated January 14, 2010. As of September 12, 2012 (the 
effective date of AD 2012-15-13), only Boeing Alert Service Bulletin 
747-53A2507, Revision 1, dated January 14, 2010, may be used to do 
the actions required by this paragraph. Do the Stage 1 inspections 
at the applicable times specified in paragraphs (h) and (i) of this 
AD, except as provided by paragraphs (g)(1) and (g)(2) of this AD. 
Accomplishment of the initial Stage 2 inspection required by 
paragraph (j) of this AD terminates the requirements of this 
paragraph. Any applicable related investigative and corrective 
actions must be done before further flight. Doing the modification 
required by paragraph (p) of this AD terminates the repetitive 
inspection requirements of this paragraph.
    (1) Where paragraph 1.E., ``Compliance,'' of Boeing Alert 
Service Bulletin 747-53A2507, dated April 21, 2005, specifies a 
compliance time relative to ``the original issue date on this 
service bulletin,'' this AD requires compliance before the specified 
compliance time after April 26, 2006 (the effective date of AD 2006-
06-11, Amendment 39-14520 (71 FR 14367, March 22, 2006)).
    (2) For any airplane that reaches the applicable compliance time 
for the initial Stage 2 inspection (as specified in Table 1, 
Compliance Recommendations, under paragraph 1.E., of Boeing Alert 
Service Bulletin 747-53A2507, dated April 21, 2005) before reaching 
the applicable compliance time for the initial Stage 1 inspection: 
Accomplishment of the initial Stage 2 inspection terminates the 
Stage 1 inspections.

(h) Retained Compliance Time for Initial Stage 1 Inspection, With No 
Changes

    This paragraph restates the requirements of paragraph (h) of AD 
2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012), with 
no changes. Do the initial Stage 1 inspection at the earlier of the 
times specified in paragraphs (h)(1) and (h)(2) of this AD.
    (1) Inspect at the earlier of the times specified in paragraphs 
(h)(1)(i) and (h)(1)(ii) of this AD.
    (i) At the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 747-53A2507, dated 
April 21, 2005.
    (ii) Before the accumulation of 10,000 total flight cycles, or 
within 250 flight cycles after November 28, 2007 (the effective date 
of AD 2007-23-18, Amendment 39-15266 (72 FR 65655, November 23, 
2007)), whichever occurs later.
    (2) Inspect at the later of the times specified in paragraphs 
(h)(2)(i) and (h)(2)(ii) of this AD.
    (i) Before the accumulation of 12,000 total flight cycles.
    (ii) Within 50 flight cycles or 20 days, whichever occurs first, 
after November 28, 2007 (the effective date of AD 2007-23-18, 
Amendment 39-15266 (72 FR 65655, November 23, 2007)).

(i) Retained Compliance Times for Repetitive Stage 1 Inspections, With 
No Changes

    This paragraph restates the requirements of paragraph (i) of AD 
2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012), with 
no changes. Repeat the Stage 1 inspection specified in paragraph (g) 
of this AD at the time specified in paragraph (i)(1) or (i)(2) of 
this AD, as applicable. Repeat the inspection thereafter at 
intervals not to exceed 250 flight cycles, until the initial Stage 2 
inspection required by paragraph (j) of this AD has been done.
    (1) For airplanes on which the initial Stage 1 inspection has 
not been accomplished as of November 28, 2007 (the effective date of 
AD 2007-23-18, Amendment 39-15266 (72 FR 65655, November 23, 2007)): 
Do the next inspection before the accumulation of 10,000 total 
flight cycles, or within 250 flight cycles after the initial Stage 1 
inspection done in accordance with paragraph (g) of this AD, 
whichever occurs later.
    (2) For airplanes on which the initial Stage 1 inspection has 
been accomplished as of November 28, 2007 (the effective date of AD 
2007-23-18, Amendment 39-15266 (72 FR 65655, November 23, 2007)): Do 
the next inspection at the applicable time specified in paragraph 
(i)(2)(i) or (i)(2)(ii) of this AD.
    (i) For airplanes that have accumulated fewer than 12,000 total 
flight cycles as of November 28, 2007 (the effective date of AD 
2007-23-18, Amendment 39-15266 (72 FR 65655, November 23, 2007)): Do 
the next inspection before the accumulation of 10,000 total flight 
cycles, or within 250 flight cycles after November 28, 2007, 
whichever occurs later.
    (ii) For airplanes that have accumulated 12,000 total flight 
cycles or more as of November 28, 2007 (the effective date of AD 
2007-23-18, Amendment 39-15266 (72 FR 65655, November 23, 2007)): Do 
the next inspection at the later of the times specified in 
paragraphs (i)(2)(ii)(A) and (i)(2)(ii)(B) of this AD.
    (A) Within 250 flight cycles after accomplishment of the initial 
Stage 1 inspection.
    (B) Within 50 flight cycles or 20 days, whichever occurs first, 
after November 28, 2007 (the effective date of AD 2007-23-18, 
Amendment 39-15266 (72 FR 65655, November 23, 2007)).

(j) Retained Repetitive Stage 2 Inspections, With No Changes

    This paragraph restates the requirements of paragraph (j) of AD 
2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012), with 
no changes. For all airplanes: Do detailed and high frequency eddy 
current inspections for cracking or discrepancies of the fasteners 
in the tension ties, shear webs, and frames at body stations 1120 
through 1220, and related investigative and corrective actions as 
applicable, by doing all actions specified in and in accordance with 
``Stage 2 Inspection'' of the Accomplishment Instructions of Boeing 
Alert Service Bulletin 747-53A2507, dated April 21, 2005, or Boeing 
Alert Service Bulletin 747-53A2507, Revision 1, dated January 14, 
2010; except as provided by paragraph (k) of this AD. Do the initial 
inspections at the earlier of the times specified in paragraphs 
(j)(1) and (j)(2) of this AD. Repeat the Stage 2 inspection 
thereafter at the applicable times specified in paragraph 1.E., 
``Compliance,'' of Boeing Alert Service Bulletin 747-53A2507, dated 
April 21, 2005, or Boeing Alert Service Bulletin 747-53A2507, 
Revision 1, dated January 14, 2010. As of September 12, 2012 (the 
effective date of AD 2012-15-13), only Boeing Alert Service Bulletin 
747-53A2507, Revision 1, dated January 14, 2010, may be used. Any 
applicable related investigative and corrective actions must be done 
before further flight. Accomplishment of the initial Stage 2 
inspection ends the repetitive Stage 1 inspections. Doing the 
modification required by paragraph (p) of this AD

[[Page 43978]]

terminates the repetitive inspection requirements of this paragraph.
    (1) Before the accumulation of 16,000 total flight cycles, or 
within 1,000 flight cycles after November 28, 2007 (the effective 
date of AD 2007-23-18, Amendment 39-15266 (72 FR 65655, November 23, 
2007)), whichever occurs later.
    (2) Before the accumulation of 10,000 total flight cycles, or 
within 1,000 flight cycles after September 12, 2012 (the effective 
date of AD 2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 
2012)), whichever occurs later.

(k) Retained Exception to Corrective Action Instructions, With No 
Changes

    This paragraph restates the requirements of paragraph (k) of AD 
2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012), with 
no changes. If any discrepancy, including but not limited to any 
crack, broken fastener, loose fastener, or missing fastener is found 
during any inspection required by paragraph (g), (h), (i), or (j) of 
this AD, and Boeing Alert Service Bulletin 747-53A2507, dated April 
21, 2005, or Boeing Alert Service Bulletin 747-53A2507, Revision 1, 
dated January 14, 2010, specifies to contact Boeing for appropriate 
action: Before further flight, repair the discrepancy using a method 
approved in accordance with the procedures specified in paragraph 
(t) of this AD.

(l) Retained Stage 2 Inspection: Work at STA 1140, With No Changes

    This paragraph restates the requirements of paragraph (l) of AD 
2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012), with 
no changes. For all airplanes: Except as provided by paragraph (o) 
of this AD, at the time specified in paragraph 1.E, ``Compliance,'' 
of Boeing Alert Service Bulletin 747-53A2507, Revision 1, dated 
January 14, 2010, do an open hole high frequency eddy current (HFEC) 
inspection for cracking in the forward and aft tension tie channels 
at 12 fastener locations inboard of the aluminum straps at STA 1140, 
and before further flight do all applicable repairs. Do all actions 
in accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 747-53A2507, Revision 1, dated January 14, 2010. 
Repeat the inspections thereafter at the time specified in paragraph 
1.E., ``Compliance,'' of Boeing Alert Service Bulletin 747-53A2507, 
Revision 1, dated January 14, 2010. Doing the modification required 
by paragraph (p) of this AD terminates the inspection requirements 
in this paragraph.

(m) Retained One-Time Inspection for Incorrectly Installed Angles, With 
No Changes

    This paragraph restates the requirements of paragraph (m) of AD 
2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012), with 
no changes. For Group 1, Configuration 1, airplanes as identified in 
Boeing Alert Service Bulletin 747-53A2507, Revision 1, dated January 
14, 2010: Except as provided by paragraph (o) of this AD, at the 
time specified in paragraph 1.E, ``Compliance,'' of Boeing Alert 
Service Bulletin 747-53A2507, Revision 1, dated January 14, 2010, do 
a detailed inspection to determine if the angle is installed 
correctly, and before further flight re-install all angles that were 
installed incorrectly. Do all actions in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2507, Revision 1, dated January 14, 2010.

(n) Retained One-time Inspection for Cracks in Frames at Previous 
Tension Tie Locations, With No Changes

    This paragraph restates the requirements of paragraph (n) of AD 
2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012), with 
no changes. For Group 1, Configuration 2, airplanes; and Groups 2 
and 3 airplanes; as identified in Boeing Alert Service Bulletin 747-
53A2507, Revision 1, dated January 14, 2010: Except as provided by 
paragraph (o) of this AD, at the time specified in paragraph 1.E, 
``Compliance,'' of Boeing Alert Service Bulletin 747-53A2507, 
Revision 1, dated January 14, 2010, do an open hole HFEC inspection 
for cracks at the fastener locations (STAs 1120, 1160, 1200, and 
1220) where the tension tie previously attached to the frame prior 
to modification to the Boeing Special Freighter or Boeing Converted 
Freighter configuration, and before further flight do all applicable 
repairs. Do all actions in accordance with the Accomplishment 
Instructions of Boeing Alert Service Bulletin 747-53A2507, Revision 
1, dated January 14, 2010. Doing the modification required by 
paragraph (p) of this AD terminates the one-time inspection 
requirements in this paragraph.

(o) Retained Exception to Boeing Alert Service Bulletin 747-53A2507, 
Revision 1, Dated January 14, 2010, With No Changes

    This paragraph restates the requirements of paragraph (o) of AD 
2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012), with 
no changes. Where paragraph 1.E., ``Compliance,'' of Boeing Alert 
Service Bulletin 747-53A2507, Revision 1, dated January 14, 2010, 
specifies a compliance time relative to ``the Revision 1 date of 
this service bulletin,'' this AD requires compliance within the 
specified compliance time after September 12, 2012 (the effective 
date of AD 2012-15-13).

(p) Retained Modification and Post-Modification Repetitive Inspections, 
With Revised Service Information

    This paragraph restates the requirements of paragraph (p) of AD 
2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012), with 
revised service information. Except as provided by paragraphs (p)(1) 
and (p)(2) of this AD: At the applicable times specified in 
paragraph 1.E, ``Compliance,'' of Boeing Service Bulletin 747-
53A2559, Revision 1, dated August 4, 2011, modify the frame-to-
tension-tie joints at STAs 1120 through 1220; do all related 
investigative and applicable corrective actions; do the repetitive 
post-modification detailed inspections for cracking of the tension 
tie and frame structure and all applicable corrective actions; and 
do the additional modification. Do all actions in accordance with 
the Accomplishment Instructions of Boeing Service Bulletin 747-
53A2559, Revision 1, dated August 4, 2011, or Boeing Alert Service 
Bulletin 747-53A2559, Revision 2, dated May 13, 2014. Modifying the 
frame-to-tension-tie joints at STAs 1120 through 1220 terminates the 
repetitive inspection requirements of paragraphs (g) and (j) of this 
AD, the inspection requirements of paragraph (l) of this AD, and the 
one-time inspection requirement of paragraph (n) of this AD. As of 
the effective date of this AD, only Boeing Alert Service Bulletin 
747-53A2559, Revision 2, dated May 13, 2014, may be used to 
accomplish the actions specified in this paragraph.
    (1) Where paragraph 1.E., ``Compliance,'' of Boeing Service 
Bulletin 747-53A2559, Revision 1, dated August 4, 2011, specifies a 
compliance time relative to ``the original issue date of this 
service bulletin,'' this AD requires compliance within the specified 
compliance time after September 12, 2012 (the effective date of AD 
2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012)).
    (2) Where Boeing Service Bulletin 747-53A2559, Revision 1, dated 
August 4, 2011, or Boeing Alert Service Bulletin 747-53A2559, 
Revision 2, dated May 13, 2014, specifies to contact Boeing for 
repair instructions or additional modification requirements: Before 
further flight, repair the cracking or do the additional actions 
using a method approved in accordance with the procedures specified 
in paragraph (t) of this AD.

(q) Retained Credit for Previous Actions, With No Changes

    This paragraph restates the credit provided by paragraph (q) of 
AD 2012-15-13, Amendment 39-17142 (77 FR 47267, August 8, 2012), 
with no changes. This paragraph provides credit for the 
corresponding actions required by paragraph (p) of this AD, if those 
actions were done before September 12, 2012 (the effective date of 
AD 2012-15-13), using Boeing Alert Service Bulletin 747-53A2559, 
dated January 8, 2009.

(r) New Repetitive Post-Modification Eddy Current Inspections

    Do an eddy current inspection of all areas of the modified 
tension ties for cracking, in accordance with Part 3 of the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2559, Revision 2, dated May 13, 2014. Do the inspection at the 
time specified in Table 2 of paragraph 1.E, ``Compliance,'' of 
Boeing Alert Service Bulletin 747-53A2559, Revision 2, dated May 13, 
2014, except where paragraph 1.E., ``Compliance,'' of Boeing Service 
Bulletin 747-53A2559, Revision 2, dated May 13, 2014, specifies a 
compliance time relative to ``the Revision 2 date of this service 
bulletin,'' this AD requires compliance within the specified 
compliance time after the effective date of this AD. If any crack is 
found, before further flight, repair the crack using a method 
approved in accordance with the procedures specified in paragraph 
(t) of this AD. If no crack is found, repeat the inspection 
thereafter at the intervals specified in paragraph 1.E, 
``Compliance,'' of Boeing Alert Service Bulletin 747-53A2559, 
Revision 2, dated May 13, 2014.

[[Page 43979]]

(s) New One-Time Surface HFEC Inspections

    Do a surface HFEC inspection of the tension tie center section, 
for cracking in the forward and aft tension tie channels between STA 
1120 through 1220, in accordance with Part 4 of the Accomplishment 
Instructions of Boeing Alert Service Bulletin 747-53A2559, Revision 
2, dated May 13, 2014. Do the inspection at the applicable time 
specified in Table 1 or Table 3 of paragraph 1.E, ``Compliance,'' of 
Boeing Alert Service Bulletin 747-53A2559, Revision 2, dated May 13, 
2014, except where paragraph 1.E., ``Compliance,'' of Boeing Alert 
Service Bulletin 747-53A2559, Revision 2, dated May 13, 2014, 
specifies a compliance time relative to ``the Revision 2 date of 
this service bulletin,'' this AD requires compliance within the 
specified compliance time after the effective date of this AD. If 
any crack is found, before further flight, repair the crack using a 
method approved in accordance with the procedures specified in 
paragraph (t) of this AD.

(t) 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 paragraph (u)(1) 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 for AD 2012-15-13, Amendment 39-
17142 (77 FR 47267, August 8, 2012), are approved as AMOCs for the 
corresponding provisions of this AD.

(u) Related Information

    (1) For more information about this AD, contact Bill Ashforth, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; 
phone: 425-917-6432; fax: 425-917-6590; email: 
bill.ashforth@faa.gov.
    (2) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
3855 Lakewood Boulevard, MC D800-0019, Long Beach, CA 90846-0001; 
telephone 206-544-5000, extension 2; fax 206-766-5683; Internet 
https://www.myboeingfleet.com. You may view this referenced service 
information at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue SW., Renton, WA. For information on the availability of this 
material at the FAA, call 425-227-1221.

    Issued in Renton, Washington, on July 16, 2015.
Suzanne Masterson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2015-18152 Filed 7-23-15; 8:45 am]
BILLING CODE 4910-13-P