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Published 2016-12-21 · Federal Register document 2016-29307

Airworthiness Directives; The Boeing Company Airplanes

Publication summary

We are adopting a new airworthiness directive (AD) for all The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747- 200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SR, and 747SP series airplanes. This AD was prompted by reports of cracking found in the splice plates, hinge fittings, terminal fittings, the upper skin of the outboard and center sections, upper chord, and rear spar webs before reaching the inspection interval specified in AD 2006-10-16. Cracked and fractured Maraging steel fasteners were also found. This AD requires repetitive inspections for cracking, an inspection to determine whether fasteners are magnetic, repetitive ultrasonic inspections for cracking and fractures of affected fasteners, and related investigative and corrective actions if necessary. We are issuing this AD to address the unsafe condition on these products.

Why this record is shown

Source: Federal Register annual FAA metadata. Acquired 2026-09-03T22:23:51.853224+00:00. The title, summary and date are source facts.

Source revision
federal_register_ad_metadata_2016-48fe8cb6c57c00b7
Source row
results[399]
Raw source SHA-256
48fe8cb6c57c00b74623eb2b71ad0abe73b95a424a8ac83fecd389da4d1e3a81

Final-rule publication

Recorded publication clauses

AD identifier printed in this edition
2016-25-05
Effective date printed in this edition
2017-01-25
Read 14 complete recorded clauses
Effective Date
(a) Effective Date

    This AD is effective January 25, 2017.

Exact source excerpt. Text positions 17478–17542, end exclusive, in the original decoded publication. SHA-256: 1173d39e4dd33434eaf5ecd5a62b00d0dd22017e60c6bf1c703898b22d80ad7d

Affected ADs
(b) Affected ADs

    This AD affects AD 2006-10-16, Amendment 39-14600 (71 FR 28570, 
May 17, 2006) (``AD 2006-10-16'').

Exact source excerpt. Text positions 17542–17665, end exclusive, in the original decoded publication. SHA-256: 4e62f291969fd07ce3c762fbcfc467328b54b211a60badc764db5d2aef679c18

Applicability wording · Applicability
(c) Applicability

    This AD applies to all The Boeing Company Model 747-100, 747-
100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 
747-400D, 747-400F, 747SR, and 747SP series airplanes; certificated 
in any category.

Exact source excerpt. Text positions 17665–17906, end exclusive, in the original decoded publication. SHA-256: 957f5b0e2a471e184e4780e793626efafd3f9449a8629d78a4209eaa1d5cfb29

Subject
(d) Subject

    Air Transport Association (ATA) of America Code 55, Stabilizers.

Exact source excerpt. Text positions 17906–17989, end exclusive, in the original decoded publication. SHA-256: e76651f310ef6540c30928159fd440108ee0f3b3e1a818ce527a8cf9b5d96299

Unsafe Condition
(e) Unsafe Condition

    This AD was prompted by reports of cracking found in the splice 
plates, hinge fittings, terminal fittings, the upper skin of the 
outboard and center sections, upper chord, and rear spar webs before 
reaching the inspection interval specified in AD 2006-10-16. Cracked 
and fractured Maraging steel fasteners were also found. We are 
issuing this AD to detect and correct this cracking, which could 
lead to reduced structural capability of the outboard and center 
sections of the horizontal stabilizer and could result in loss of 
control of the airplane.

Exact source excerpt. Text positions 17989–18575, end exclusive, in the original decoded publication. SHA-256: 515ffa5b856c8ae8d4aa2b1b2e89fe5ad717c97c2e6fea0236b4bd778e34a170

Compliance
(f) Compliance

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

Exact source excerpt. Text positions 18575–18677, end exclusive, in the original decoded publication. SHA-256: 00fbfa31932483f627d0ce0a11cbd2e35e15d9231842b91ac85623ce533912d3

Repetitive Inspections/Investigative and Corrective Actions
(g) Repetitive Inspections/Investigative and Corrective Actions

    At the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015, except as required by paragraphs (h)(1) and 
(h)(2) of this AD: Do the applicable actions specified in paragraphs 
(g)(1), (g)(2), (g)(3), and (g)(4) of this AD, and all applicable 
related investigative and corrective actions, in accordance with the 
applicable part of the Accomplishment Instructions of Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015, except as 
required by paragraph (h)(3) of this AD. Do all applicable related 
investigative and corrective actions before further flight. Repeat 
the applicable inspections specified in paragraphs (g)(1), (g)(2), 
(g)(3), and (g)(4) of this AD at the applicable times specified in 
paragraph 1.E., ``Compliance,'' of Boeing Service Bulletin 747-
55A2050, Revision 2, dated January 23, 2015.
    (1) For Group 1 through 3 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015: Do non-
destructive test (NDT) inspections (ultrasonic, high frequency eddy 
current, and low frequency eddy current inspections) or open-hole 
NDT inspections (high frequency eddy current inspections) of Zone B 
for cracking, in accordance with Part 3 or Part 4 of the 
Accomplishment Instructions of Boeing Service Bulletin 747-55A2050, 
Revision 2, dated January 23, 2015, as applicable. Accomplishing a 
Zone B inspection required by this paragraph terminates the 
inspections required by paragraph (g) of AD 2006-10-16 for the 
inspected area only.
    (2) For Group 4 through 6 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015: Do open-
hole NDT inspections (high frequency eddy current inspections) of 
Zone B for cracking, in accordance with Part 4 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015. Accomplishing a Zone B inspection required 
by this paragraph terminates the inspections required by paragraph 
(i) of AD 2006-10-16 for the inspected area only.
    (3) For Group 7 through 9 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015: Do 
inspections of Zone A (detailed or high frequency eddy current 
inspections) and Zone B (open-hole high frequency eddy current 
inspections) for cracking, in accordance with Part 1, Part 2, or 
Part 4 of the Accomplishment Instructions of Boeing Service Bulletin 
747-55A2050, Revision 2, dated January 23, 2015, as applicable. 
Accomplishing Zone A and Zone B inspections required by this 
paragraph terminates the inspections required by paragraphs (f), 
(i), and (l) of AD 2006-10-16 for the inspected area only.
    (4) For Group 1 through 3 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015: Do an 
inspection of Zone C Maraging or H-11 steel fasteners to determine 
whether fasteners are magnetic, in accordance with Part 6 of the 
Accomplishment Instructions of Boeing Service Bulletin 747-55A2050, 
Revision 2, dated January 23, 2015.

Exact source excerpt. Text positions 18677–21895, end exclusive, in the original decoded publication. SHA-256: 08f647e75e129002ef0d90e366629efa9e7e64d72ae6bac1f1cb95e3613c0ed4

Exceptions to Service Bulletin Specifications
(h) Exceptions to Service Bulletin Specifications

    (1) Where Boeing Service Bulletin 747-55A2050, Revision 2, dated 
January 23, 2015, specifies a compliance time ``after the Revision 2 
date of this service bulletin,'' this AD requires compliance within 
the specified compliance time after the effective date of this AD.
    (2) The Condition column of Table 1 of paragraph 1.E., 
``Compliance,'' of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015, refers to airplanes with certain total 
flight cycles and total flight hours. This AD, however, applies to 
the

[[Page 93589]]

airplanes with the specified total flight cycles and total flight 
hours as of the effective date of this AD.
    (3) Where Boeing Service Bulletin 747-55A2050, Revision 2, dated 
January 23, 2015, specifies to contact Boeing for repair 
instructions: Before further flight, repair using a method approved 
in accordance with the procedures specified in paragraph (l) of this 
AD.

Exact source excerpt. Text positions 21895–22886, end exclusive, in the original decoded publication. SHA-256: 09ea3915efd4a473c65323701f7414de408fffa7488b12d6fa4d67ef4c4e1f88

Optional Terminating Action
(i) Optional Terminating Action

    (1) For Group 1 through 3 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015: 
Accomplishing the Zone B modification, including all applicable 
related investigative and corrective actions, specified in Part 7 of 
the Accomplishment Instructions of Boeing Service Bulletin 747-
55A2050, Revision 2, dated January 23, 2015, except as required by 
paragraph (h)(3) of this AD, terminates the repetitive inspections 
specified in paragraphs (i)(1)(i) through (i)(1)(iv) of this AD for 
the modified area only.
    (i) Inspections required by paragraph (g)(1) of this AD for Zone 
B, as specified in Part 3 and Part 4 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015.
    (ii) Inspections required by paragraph (g)(4) of this AD for 
Zone C, as specified in Part 6 of the Accomplishment Instructions of 
Boeing Service Bulletin 747-55A2050, Revision 2, dated January 23, 
2015.
    (iii) Inspections required by paragraph (g) of AD 2006-10-16 for 
Zone B, as specified in Part 3 of the Accomplishment Instructions of 
Boeing Service Bulletin 747-55A2050, Revision 2, dated January 23, 
2015.
    (iv) Inspections required by paragraph (k) of AD 2006-10-16 for 
Zone C, as specified in Part 5 of the Accomplishment Instructions of 
Boeing Service Bulletin 747-55A2050, Revision 2, dated January 23, 
2015.
    (2) For Group 1 through 3 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015: 
Accomplishing the Zone B open-hole NDT inspection, repairing any 
cracking as applicable, and replacing fasteners as specified in Part 
4 of the Accomplishment Instructions of Boeing Service Bulletin 747-
55A2050, Revision 2, dated January 23, 2015, terminates the actions 
specified in paragraphs (i)(2)(i) and (i)(2)(ii) of this AD for the 
inspected area only.
    (i) The inspections required by paragraph (g)(4) of this AD for 
Zone C, as specified in Part 6 of the Accomplishment Instructions of 
Boeing Service Bulletin 747-55A2050, Revision 2, dated January 23, 
2015.
    (ii) The repetitive inspections required by paragraph (k) of AD 
2006-10-16 for Zone C, as specified in Part 5 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015.
    (3) For Group 4 through 9 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015: 
Accomplishing the Zone B modification, including all applicable 
related investigative and corrective actions, specified in Part 7 of 
the Accomplishment Instructions of Boeing Service Bulletin 747-
55A2050, Revision 2, dated January 23, 2015, except as required by 
paragraph (h)(3) of this AD, terminates the actions specified in 
paragraphs (i)(3)(i) and (i)(3)(ii) of this AD for the modified area 
only.
    (i) The repetitive inspections required by paragraph (g)(2) or 
(g)(3) of this AD, as applicable, only for Zone B, as specified in 
Part 4 of the Accomplishment Instructions of Boeing Service Bulletin 
747-55A2050, Revision 2, dated January 23, 2015.
    (ii) The repetitive inspections required by paragraph (i) of AD 
2006-10-16 for Zone B, as specified in Part 4 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015.

Exact source excerpt. Text positions 22886–26289, end exclusive, in the original decoded publication. SHA-256: 7c0509250e6cfd61e5f9148177db8bc978ae37940cf6853ea58fd0334c33a7ff

Repetitive Post-Modification Inspections and Corrective Actions
(j) Repetitive Post-Modification Inspections and Corrective Actions

    At the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015: Do the applicable inspections specified in 
paragraphs (j)(1) and (j)(2) of this AD, and all applicable 
corrective actions, in accordance with Part 8 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015, except as required by paragraph (h)(3) of 
this AD. Do all applicable corrective actions before further flight. 
Repeat the applicable inspections at the applicable times specified 
in paragraph 1.E., ``Compliance,'' of Boeing Service Bulletin 747-
55A2050, Revision 2, dated January 23, 2015.
    (1) For Group 1 through 3 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015, on which 
the Zone B modification specified in paragraph (i)(1) of this AD is 
done: Do non-destructive test (NDT) inspections (ultrasonic, high 
frequency eddy current, and low frequency eddy current inspections) 
or open-hole NDT inspections (high frequency eddy current 
inspections) of Zone B for cracking.
    (2) For Group 4 through 9 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015, on which 
the Zone B modification specified in paragraph (i)(3) of this AD is 
done: Do open-hole NDT inspections (high frequency eddy current 
inspections) of Zone B for cracking.

Exact source excerpt. Text positions 26289–27815, end exclusive, in the original decoded publication. SHA-256: 7fc048cd9bec8574812935ab00588479f343110968bff861858817710c4b7ab3

Parts Installation Prohibition
(k) Parts Installation Prohibition

    As of the effective date of this AD, no person may install any 
Maraging or H-11 steel fasteners in the locations specified in this 
AD. Where Boeing Service Bulletin 747-55A2050, Revision 2, dated 
January 23, 2015, specifies to install H-11 bolts (kept fasteners), 
this AD requires installation of Inconel bolts.

Exact source excerpt. Text positions 27815–28172, end exclusive, in the original decoded publication. SHA-256: a79119a30dda4c378f9e42b0e351d898c90c49a33a766f50edc84443ceaa1c3f

Alternative Methods of Compliance (AMOCs)
(l) 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 (m) of this AD. 
Information may be emailed to: [email protected].
    (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 for AD 2006-10-16, are approved as AMOCs for 
the corresponding provisions of paragraph (g) of this AD, except for 
approved AMOCs that allow installation of Maraging or H-11 steel 
fasteners.

Exact source excerpt. Text positions 28172–29602, end exclusive, in the original decoded publication. SHA-256: e01b65f5ddef952533c3313a60ef2be45c7ebac5bdd68e774ec6af666e21dfc1

Related Information
(m) Related Information

    For more information about this AD, contact Nathan Weigand, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle ACO, 
1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6428; 
fax: 425-917-6590; email: [email protected].

Exact source excerpt. Text positions 29602–29871, end exclusive, in the original decoded publication. SHA-256: f7f3dba0278a7896186497ae8aa5b41734ba67d6da8c4c5e7a65c9418b19c56f

Material Incorporated by Reference
(n) 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.
    (i) Boeing Service Bulletin 747-55A2050, Revision 2, dated 
January 23, 2015.
    (ii) Reserved.
    (3) For 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.
    (4) You may view this 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.
    (5) 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.

Exact source excerpt. Text positions 29871–31124, end exclusive, in the original decoded publication. SHA-256: 54dd35fb43b72877910f82a68a8e0b09d43ca103174af2d85ef002061021f1e3

Explicit nonreplacing affects wording

This publication says it affects these identifiers; they have not been treated as replacement targets.

Find all recorded historical references to AD 2016-25-05 · 0 printed reference observations in this pinned collection.

These are observations from one dated publication. Current legal status is unknown; aircraft applicability, installed configuration, compliance and burden require separate evidence. Missing or unparsed conditions remain unknown.

Why these observations are shown

They were extracted offline from the same immutable official HTML source as the complete recorded text. The dated source wording, original text coordinates and exact quote digests are retained. PDF/text agreement and current regulatory effect have not been qualified.

Observation revision: whole-ad-publication-clause-observations-1.0.1. Text SHA-256: 10b081cc5667a29cbc7a75f0bbf3e72c25e10e00faef13d4c6acc1c78b4ee103. Source manifest: bedeb4c2ceea180ce55348d057e6ca476dba8bd099b3b3c9fc853a46115967be.

Official source · 2016-12-21

Publication text

This is the complete recorded text of this dated publication.

Current legal effect is unknown. Aircraft applicability, installed configuration and compliance require separate evidence. PDF/text agreement has not been evaluated.

Read the complete official publication text
[Federal Register Volume 81, Number 245 (Wednesday, December 21, 2016)]
[Rules and Regulations]
[Pages 93585-93589]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-29307]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-5816; Directorate Identifier 2015-NM-029-AD; 
Amendment 39-18731; AD 2016-25-05]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: We are adopting a new airworthiness directive (AD) for all The 
Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-
200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SR, and 747SP 
series airplanes. This AD was prompted by reports of cracking found in 
the splice plates, hinge fittings, terminal fittings, the upper skin of 
the outboard

[[Page 93586]]

and center sections, upper chord, and rear spar webs before reaching 
the inspection interval specified in AD 2006-10-16. Cracked and 
fractured Maraging steel fasteners were also found. This AD requires 
repetitive inspections for cracking, an inspection to determine whether 
fasteners are magnetic, repetitive ultrasonic inspections for cracking 
and fractures of affected fasteners, and related investigative and 
corrective actions if necessary. We are issuing this AD to address the 
unsafe condition on these products.

DATES: This AD is effective January 25, 2017.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of January 25, 
2017.

ADDRESSES: For service information identified in this final rule, 
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-
5816.

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-
5816; 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 Docket 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: Nathan Weigand, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office 
(ACO), 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-
6428; fax: 425-917-6590; email: [email protected].

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to supersede AD 2006-10-16, Amendment 39-14600 (71 FR 28570, 
May 17, 2006) (``AD 2006-10-16''). AD 2006-10-16 applies to all The 
Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-
200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SR, and 747SP 
series airplanes. The NPRM published in the Federal Register on 
November 27, 2015 (80 FR 74052) (``the NPRM''). The NPRM was prompted 
by reports of cracking found in the splice plates, hinge fittings, 
terminal fittings, the upper skin of the outboard and center sections, 
upper chord, and rear spar webs before reaching the inspection interval 
specified in AD 2006-10-16. Cracked and fractured Maraging steel 
fasteners were also found. The NPRM proposed to reduce the compliance 
time for certain inspections and add repetitive inspections for 
cracking of the splice plates, hinge fittings, terminal fittings, upper 
skin of the outboard and center sections, and rear spar webs in Zone B. 
The NPRM also proposed to require an inspection to determine whether 
fasteners are magnetic in Zone C, repetitive ultrasonic inspections for 
cracking and fractures of affected fasteners, and related investigative 
and corrective actions if necessary. The NPRM also added an optional 
modification, which would terminate certain repetitive inspections, 
provided post-modification inspections and corrective action are done 
if necessary. We are issuing this AD to detect and correct this 
cracking, which could lead to reduced structural capability of the 
outboard and center sections of the horizontal stabilizer and could 
result in loss of control of the airplane.

Comments

    We gave the public the opportunity to participate in developing 
this AD. The following presents the comments received on the NPRM and 
the FAA's response to each comment.

Request To Clarify Inspections

    Atlas Airlines, United Airlines, and The Boeing Company requested 
that we clarify the inspection required by the proposed AD. Atlas 
Airlines stated that the ``Proposed AD Requirements'' paragraph of the 
NPRM states that the proposed AD would retain all the requirements of 
AD 2006-10-16. Atlas Airlines also stated that paragraph (f) of AD 
2006-10-16 is not included in the proposed AD and noted that paragraph 
(g)(3) of the proposed AD identifies only Groups 7 through 9 as the 
applicable groups for the Zone A inspections. Atlas Airlines asked for 
clarification of the Zone A inspections.
    Boeing noted that AD 2006-10-16 includes Zone C inspections as 
specified in Part 5 of Boeing Service Bulletin 747-55A2050, Revision 1, 
dated May 1, 2003, and included Zone A inspections for Groups 1 through 
6. Boeing noted that these inspections have not been removed by Boeing 
Service Bulletin 747-55A2050, Revision 2, dated January 23, 2015. 
Boeing also requested that we revise the proposed AD to address the 
Zone C inspections in Part 5 of Boeing Service Bulletin 747-55A2050, 
Revision 2, dated January 23, 2015, and the Zone A inspections for 
Groups 1 through 6.
    United Airlines disagreed with not restating the requirements of AD 
2006-10-16. United Airlines stated that operators might miss that Zone 
A inspections and Zone C, Part 5, inspections required by AD 2006-10-16 
are intended to be mandated. United Airlines noted that although the 
preamble of the NPRM stated that all inspections of AD 2006-10-16 are 
retained, paragraph (g) of the proposed AD only specifies new 
requirements and does not include certain Zone A inspections and Zone 
C, Part 5, inspections.
    We agree that clarification is necessary. As stated in the preamble 
to the NPRM, we intended to retain all requirements of AD 2006-10-16. 
However, the actions specified in the proposed AD do not include the 
inspections referred to by the commenters. We have determined that 
instead of including those actions in this final rule, we will issue 
this action as a stand-alone AD. Thus, AD 2006-10-16 is not superseded, 
making it clear that all actions in AD 2006-10-16 continue to be 
required. In addition, we have revised this AD to specify when 
accomplishing certain actions in this AD terminates actions specified 
in AD 2006-10-16. We have made the following changes:
    <bullet> Revised paragraph (g)(1) of this AD to specify that 
accomplishing a Zone B inspection required by paragraph (g)(1) of this 
AD terminates the inspections required by paragraph (g) of AD 2006-10-
16 for the inspected area only.
    <bullet> Revised paragraph (g)(2) of this AD to specify that 
accomplishing a Zone B inspection required by paragraph (g)(2) of this 
AD terminates the inspections required by paragraph (i) of AD 2006-10-
16 for the inspected area only.
    <bullet> Revised paragraph (g)(3) of this AD to specify that 
accomplishing Zone A and Zone B inspections required by

[[Page 93587]]

paragraph (g)(3) of this AD terminates the inspections required by 
paragraphs (f), (i), and (l) of AD 2006-10-16 for the inspected area 
only.
    <bullet> Added paragraph (i)(1)(iii) to this AD to clarify that 
accomplishing the actions specified in paragraph (i)(1) of this AD 
terminates inspections required by paragraph (g) of AD 2006-10-16 for 
Zone B, as specified in Part 3 of the Accomplishment Instructions of 
Boeing Service Bulletin 747-55A2050, Revision 2, dated January 23, 
2015, for the modified area only.
    <bullet> Added paragraph (i)(1)(iv) to this AD to clarify that 
accomplishing the actions specified in paragraph (i) of this AD 
terminates inspections required by paragraph (k) of AD 2006-10-16 for 
Zone C, as specified in Part 5 of the Accomplishment Instructions of 
Boeing Service Bulletin 747-55A2050, Revision 2, dated January 23, 
2015, for the modified area only.
    <bullet> Added paragraph (i)(2)(ii) of this AD to clarify that 
accomplishing the actions specified in paragraph (i)(2) of this AD 
terminates the repetitive inspections required by paragraph (k) of AD 
2006-10-16 for Zone C, as specified in Part 5 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-55A2050, Revision 2, dated 
January 23, 2015, for the inspected area only.
    <bullet> Added paragraph (i)(3)(ii) of this AD to clarify that 
accomplishing the actions specified in paragraph (i)(3) of this AD 
terminates the repetitive inspections required by paragraph (i) of AD 
2006-10-16 for Zone B, as specified in Part 4 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-55A2050, Revision 2, dated 
January 23, 2015, for the modified area only.

Request To Update Terminating Action Language for Zone C Inspections

    Boeing requested that we revise paragraph (i)(2) of the proposed AD 
to clarify which Zone C inspections are terminated. Boeing noted that 
paragraph (i)(2) of the proposed AD specifies that the actions 
terminate Zone C inspections specified in Part 6 of Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015, and noted 
that Zone C inspections in Part 5 of Boeing Service Bulletin 747-
55A2050, Revision 2, dated January 23, 2015, are also terminated.
    We agree to clarify the terminating action for the Zone C 
inspections, and have revised paragraph (i)(2) of this AD accordingly.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
this AD with the change described previously and minor editorial 
changes. We have determined that these minor changes:
    <bullet> Are consistent with the intent that was proposed in the 
NPRM for correcting the unsafe condition; and
    <bullet> Do not add any additional burden upon the public than was 
already proposed in the NPRM.
    We also determined that these changes will not increase the 
economic burden on any operator or increase the scope of this AD.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Service Bulletin 747-55A2050, Revision 2, dated 
January 23, 2015. The service information describes procedures for 
accomplishing Zone A, Zone B, and Zone C inspections for cracking of 
the upper skin and upper rear spar chord of the outboard and center 
sections of the horizontal stabilizer, and related investigative and 
corrective actions if necessary. The service information also describes 
procedures for a magnetic inspection to determine the type of 
fasteners, ultrasonic inspections for cracking and fractures of 
affected fasteners, and related investigative and corrective actions if 
necessary. 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.

Costs of Compliance

    We estimate that this AD affects 116 airplanes of U.S. registry.
    We estimate the following costs to comply with this AD:

                                        Estimated Costs--Required Actions
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
             Action                     Labor cost          Parts cost     Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Zone A Inspections (required by  8 work-hours x $85 per               $0  $680..............  Up to $78,880.
 AD 2006-10-16).                  hour = $680.
Zone B Open-hole nondestructive  30 work-hours x $85 per               0  2,550.............  Up to $295,800.
 testing (NDT) Inspection         hour = $2,550.
 (required by AD 2006-10-16 for
 Groups 3, 4, and 5 airplanes;
 and for Groups 1, 2, and 3
 airplanes, if done).
Zone C Maraging or H-11 Steel    8 work-hours x $85 per                0  680...............  Up to $78,880.
 Fastener Inspection (required    hour = $680.
 by AD 2006-10-16 for Groups 1,
 2, and 3 airplanes).
New Zone B Inspections.........  248 work-hours x $85                  0  21,080............  $2,445,280.
                                  per hour = $21,080.
New Zone C Inspection..........  26 work-hours x $85 per               0  2,210.............  $256,360.
                                  hour = $2,210.
----------------------------------------------------------------------------------------------------------------


                                        Estimated Costs--Optional Actions
----------------------------------------------------------------------------------------------------------------
              Action                          Labor cost                  Parts cost          Cost per product
----------------------------------------------------------------------------------------------------------------
Open-hole NDT Inspections (high     Up to 298 work-hours x $85 per  $0...................  Up to $25,330.
 frequency eddy current              hour = up to $25,330.
 inspections).
Zone B Modification...............  Up to 313 work-hours x $85 per  Up to $3,486.........  Up to $30,091.
                                     hour = up to $26,605.
Post-Modification Inspections.....  Up to 298 work-hours x $85 per  $0...................  Up to $25,330.
                                     hour = up to $25,330.
----------------------------------------------------------------------------------------------------------------


[[Page 93588]]

    We have received no definitive data that would enable us to provide 
a cost estimate for the on-condition actions 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

    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 adding the following new airworthiness 
directive (AD):

2016-25-05 The Boeing Company: Amendment 39-18731; Docket No. FAA-
2015-5816; Directorate Identifier 2015-NM-029-AD.

(a) Effective Date

    This AD is effective January 25, 2017.

(b) Affected ADs

    This AD affects AD 2006-10-16, Amendment 39-14600 (71 FR 28570, 
May 17, 2006) (``AD 2006-10-16'').

(c) Applicability

    This AD applies to all The Boeing Company Model 747-100, 747-
100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 
747-400D, 747-400F, 747SR, and 747SP series airplanes; certificated 
in any category.

(d) Subject

    Air Transport Association (ATA) of America Code 55, Stabilizers.

(e) Unsafe Condition

    This AD was prompted by reports of cracking found in the splice 
plates, hinge fittings, terminal fittings, the upper skin of the 
outboard and center sections, upper chord, and rear spar webs before 
reaching the inspection interval specified in AD 2006-10-16. Cracked 
and fractured Maraging steel fasteners were also found. We are 
issuing this AD to detect and correct this cracking, which could 
lead to reduced structural capability of the outboard and center 
sections of the horizontal stabilizer and could result in loss of 
control of the airplane.

(f) Compliance

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

(g) Repetitive Inspections/Investigative and Corrective Actions

    At the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015, except as required by paragraphs (h)(1) and 
(h)(2) of this AD: Do the applicable actions specified in paragraphs 
(g)(1), (g)(2), (g)(3), and (g)(4) of this AD, and all applicable 
related investigative and corrective actions, in accordance with the 
applicable part of the Accomplishment Instructions of Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015, except as 
required by paragraph (h)(3) of this AD. Do all applicable related 
investigative and corrective actions before further flight. Repeat 
the applicable inspections specified in paragraphs (g)(1), (g)(2), 
(g)(3), and (g)(4) of this AD at the applicable times specified in 
paragraph 1.E., ``Compliance,'' of Boeing Service Bulletin 747-
55A2050, Revision 2, dated January 23, 2015.
    (1) For Group 1 through 3 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015: Do non-
destructive test (NDT) inspections (ultrasonic, high frequency eddy 
current, and low frequency eddy current inspections) or open-hole 
NDT inspections (high frequency eddy current inspections) of Zone B 
for cracking, in accordance with Part 3 or Part 4 of the 
Accomplishment Instructions of Boeing Service Bulletin 747-55A2050, 
Revision 2, dated January 23, 2015, as applicable. Accomplishing a 
Zone B inspection required by this paragraph terminates the 
inspections required by paragraph (g) of AD 2006-10-16 for the 
inspected area only.
    (2) For Group 4 through 6 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015: Do open-
hole NDT inspections (high frequency eddy current inspections) of 
Zone B for cracking, in accordance with Part 4 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015. Accomplishing a Zone B inspection required 
by this paragraph terminates the inspections required by paragraph 
(i) of AD 2006-10-16 for the inspected area only.
    (3) For Group 7 through 9 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015: Do 
inspections of Zone A (detailed or high frequency eddy current 
inspections) and Zone B (open-hole high frequency eddy current 
inspections) for cracking, in accordance with Part 1, Part 2, or 
Part 4 of the Accomplishment Instructions of Boeing Service Bulletin 
747-55A2050, Revision 2, dated January 23, 2015, as applicable. 
Accomplishing Zone A and Zone B inspections required by this 
paragraph terminates the inspections required by paragraphs (f), 
(i), and (l) of AD 2006-10-16 for the inspected area only.
    (4) For Group 1 through 3 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015: Do an 
inspection of Zone C Maraging or H-11 steel fasteners to determine 
whether fasteners are magnetic, in accordance with Part 6 of the 
Accomplishment Instructions of Boeing Service Bulletin 747-55A2050, 
Revision 2, dated January 23, 2015.

(h) Exceptions to Service Bulletin Specifications

    (1) Where Boeing Service Bulletin 747-55A2050, Revision 2, dated 
January 23, 2015, specifies a compliance time ``after the Revision 2 
date of this service bulletin,'' this AD requires compliance within 
the specified compliance time after the effective date of this AD.
    (2) The Condition column of Table 1 of paragraph 1.E., 
``Compliance,'' of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015, refers to airplanes with certain total 
flight cycles and total flight hours. This AD, however, applies to 
the

[[Page 93589]]

airplanes with the specified total flight cycles and total flight 
hours as of the effective date of this AD.
    (3) Where Boeing Service Bulletin 747-55A2050, Revision 2, dated 
January 23, 2015, specifies to contact Boeing for repair 
instructions: Before further flight, repair using a method approved 
in accordance with the procedures specified in paragraph (l) of this 
AD.

(i) Optional Terminating Action

    (1) For Group 1 through 3 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015: 
Accomplishing the Zone B modification, including all applicable 
related investigative and corrective actions, specified in Part 7 of 
the Accomplishment Instructions of Boeing Service Bulletin 747-
55A2050, Revision 2, dated January 23, 2015, except as required by 
paragraph (h)(3) of this AD, terminates the repetitive inspections 
specified in paragraphs (i)(1)(i) through (i)(1)(iv) of this AD for 
the modified area only.
    (i) Inspections required by paragraph (g)(1) of this AD for Zone 
B, as specified in Part 3 and Part 4 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015.
    (ii) Inspections required by paragraph (g)(4) of this AD for 
Zone C, as specified in Part 6 of the Accomplishment Instructions of 
Boeing Service Bulletin 747-55A2050, Revision 2, dated January 23, 
2015.
    (iii) Inspections required by paragraph (g) of AD 2006-10-16 for 
Zone B, as specified in Part 3 of the Accomplishment Instructions of 
Boeing Service Bulletin 747-55A2050, Revision 2, dated January 23, 
2015.
    (iv) Inspections required by paragraph (k) of AD 2006-10-16 for 
Zone C, as specified in Part 5 of the Accomplishment Instructions of 
Boeing Service Bulletin 747-55A2050, Revision 2, dated January 23, 
2015.
    (2) For Group 1 through 3 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015: 
Accomplishing the Zone B open-hole NDT inspection, repairing any 
cracking as applicable, and replacing fasteners as specified in Part 
4 of the Accomplishment Instructions of Boeing Service Bulletin 747-
55A2050, Revision 2, dated January 23, 2015, terminates the actions 
specified in paragraphs (i)(2)(i) and (i)(2)(ii) of this AD for the 
inspected area only.
    (i) The inspections required by paragraph (g)(4) of this AD for 
Zone C, as specified in Part 6 of the Accomplishment Instructions of 
Boeing Service Bulletin 747-55A2050, Revision 2, dated January 23, 
2015.
    (ii) The repetitive inspections required by paragraph (k) of AD 
2006-10-16 for Zone C, as specified in Part 5 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015.
    (3) For Group 4 through 9 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015: 
Accomplishing the Zone B modification, including all applicable 
related investigative and corrective actions, specified in Part 7 of 
the Accomplishment Instructions of Boeing Service Bulletin 747-
55A2050, Revision 2, dated January 23, 2015, except as required by 
paragraph (h)(3) of this AD, terminates the actions specified in 
paragraphs (i)(3)(i) and (i)(3)(ii) of this AD for the modified area 
only.
    (i) The repetitive inspections required by paragraph (g)(2) or 
(g)(3) of this AD, as applicable, only for Zone B, as specified in 
Part 4 of the Accomplishment Instructions of Boeing Service Bulletin 
747-55A2050, Revision 2, dated January 23, 2015.
    (ii) The repetitive inspections required by paragraph (i) of AD 
2006-10-16 for Zone B, as specified in Part 4 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015.

(j) Repetitive Post-Modification Inspections and Corrective Actions

    At the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015: Do the applicable inspections specified in 
paragraphs (j)(1) and (j)(2) of this AD, and all applicable 
corrective actions, in accordance with Part 8 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-55A2050, Revision 2, 
dated January 23, 2015, except as required by paragraph (h)(3) of 
this AD. Do all applicable corrective actions before further flight. 
Repeat the applicable inspections at the applicable times specified 
in paragraph 1.E., ``Compliance,'' of Boeing Service Bulletin 747-
55A2050, Revision 2, dated January 23, 2015.
    (1) For Group 1 through 3 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015, on which 
the Zone B modification specified in paragraph (i)(1) of this AD is 
done: Do non-destructive test (NDT) inspections (ultrasonic, high 
frequency eddy current, and low frequency eddy current inspections) 
or open-hole NDT inspections (high frequency eddy current 
inspections) of Zone B for cracking.
    (2) For Group 4 through 9 airplanes identified in Boeing Service 
Bulletin 747-55A2050, Revision 2, dated January 23, 2015, on which 
the Zone B modification specified in paragraph (i)(3) of this AD is 
done: Do open-hole NDT inspections (high frequency eddy current 
inspections) of Zone B for cracking.

(k) Parts Installation Prohibition

    As of the effective date of this AD, no person may install any 
Maraging or H-11 steel fasteners in the locations specified in this 
AD. Where Boeing Service Bulletin 747-55A2050, Revision 2, dated 
January 23, 2015, specifies to install H-11 bolts (kept fasteners), 
this AD requires installation of Inconel bolts.

(l) 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 (m) of this AD. 
Information may be emailed to: [email protected].
    (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 for AD 2006-10-16, are approved as AMOCs for 
the corresponding provisions of paragraph (g) of this AD, except for 
approved AMOCs that allow installation of Maraging or H-11 steel 
fasteners.

(m) Related Information

    For more information about this AD, contact Nathan Weigand, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle ACO, 
1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6428; 
fax: 425-917-6590; email: [email protected].

(n) 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.
    (i) Boeing Service Bulletin 747-55A2050, Revision 2, dated 
January 23, 2015.
    (ii) Reserved.
    (3) For 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.
    (4) You may view this 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.
    (5) 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 November 25, 2016.
John P. Piccola, Jr.,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2016-29307 Filed 12-20-16; 8:45 am]
BILLING CODE 4910-13-P


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