AD 2020-21-17

[Federal Register Volume 85, Number 238 (Thursday, December 10, 2020)]
[Rules and Regulations]
[Pages 79418-79422]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2020-27007]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0984; Product Identifier 2019-NM-161-AD; Amendment 
39-21290; AD 2020-21-17]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2018-16-
05, which applied to certain The Boeing Company Model 757 airplanes. AD 
2018-16-05 required repetitive inspections for skin cracking and shim 
migration at the upper link drag fittings, diagonal brace cracking, and 
fastener looseness; and applicable on-condition actions. This AD 
retains the actions required by AD 2018-16-05, reduces the compliance 
times for certain inspections, and adds repetitive inspections at 
certain fastener hole locations and applicable on-condition actions. 
This AD was prompted by reports of bolt rotation in the engine drag 
fitting joint and fastener heads; an inspection of the fastener holes 
revealed that cracks were found in the skin. This AD was also prompted 
by a report of multiple cracks in the drag fitting at fastener holes 
found during an inspection required by AD 2018-16-05. The FAA is 
issuing this AD to address the unsafe condition on these products.

DATES: This AD is effective January 14, 2021.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of January 14, 
2021.

ADDRESSES: For service information identified in this final rule, 
contact Boeing Commercial Airplanes, Attention: Contractual & Data 
Services

[[Page 79419]]

(C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; 
telephone 562-797-1717; internet <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>. You may 
view this service information at the FAA, Airworthiness Products 
Section, Operational Safety Branch, 2200 South 216th St., Des Moines, 
WA. For information on the availability of this material at the FAA, 
call 206-231-3195. It is also available on the internet at <a href="https://www.regulations.gov">https://www.regulations.gov</a> by searching for and locating Docket No. FAA-2019-
0984.

Examining the AD Docket

    You may examine the AD docket on the internet at <a href="https://www.regulations.gov">https://www.regulations.gov</a> by searching for and locating Docket No. FAA-2019-
0984; or in person at Docket Operations between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays. The AD docket contains 
this final rule, any comments received, and other information. The 
address for Docket Operations is 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: Chandra Ramdoss, Aerospace Engineer, 
Airframe Section, FAA, Los Angeles ACO Branch, 3960 Paramount 
Boulevard, Lakewood, CA 90712-4137; phone: 562-627-5239; fax: 562-627-
5210; email: <a href="/cdn-cgi/l/email-protection#36555e57585244575243425e1844575b525945457650575718515940"><span class="__cf_email__" data-cfemail="92f1faf3fcf6e0f3f6e7e6fabce0f3fff6fde1e1d2f4f3f3bcf5fde4">[email&#160;protected]</span></a>.

SUPPLEMENTARY INFORMATION:

Discussion

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to supersede AD 2018-16-05, Amendment 39-19345 (83 FR 
38250, August 6, 2018) (``AD 2018-16-05''). AD 2018-16-05 applied to 
certain The Boeing Company Model 757-200, -200PF, -200CB, and -300 
series airplanes. The NPRM published in the Federal Register on 
December 17, 2019 (84 FR 68822). The NPRM was prompted by reports of 
bolt rotation in the engine drag fitting joint and fastener heads; an 
inspection of the fastener holes revealed that cracks were found in the 
skin. The NPRM was also prompted by a report of multiple cracks found 
in the drag fitting at fastener holes during inspections required by AD 
2018-16-05. The NPRM proposed to continue to require repetitive 
inspections for skin cracking and shim migration at the upper link drag 
fittings, diagonal brace cracking, and fastener looseness; and 
applicable on-condition actions. The NPRM also proposed to reduce the 
compliance times for certain inspections and add repetitive inspections 
at certain fastener hole locations and applicable on-condition actions. 
The FAA is issuing this AD to address cracking in the wing upper skin 
and forward drag fittings, which could lead to a compromised upper link 
and reduced structural integrity of the engine strut.

Comments

    The FAA 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.

Support for the NPRM

    United Airlines (United) and American Airlines (American) stated 
their concurrence with the NPRM.

Effect of Winglets on Accomplishment of the Proposed Actions

    Aviation Partners Boeing (APB) stated that they have reviewed the 
NPRM and have determined that the installation of winglets per 
Supplemental Type Certificate (STC) ST01518SE does not affect the 
accomplishment of the manufacturer's service instructions.
    The FAA agrees with the commenter that STC ST01518SE does not 
affect the accomplishment of the manufacturer's service instructions. 
The FAA has redesignated paragraph (c) of the proposed AD as paragraph 
(c)(1) of this AD and added paragraph (c)(2) to this AD to state that 
installation of STC ST01518SE does not affect the ability to accomplish 
the actions required by this AD. Therefore, for airplanes on which STC 
ST00830SE 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.

Requests To Increase the Inspection Intervals

    American and United requested that the repetitive interval for the 
general visual inspection of the diagonal brace and diagonal brace 
fittings be increased from 2,100 flight cycles (FC) to 3,000 FC. In 
addition, American requested that the initial interval for the 
inspection also be increased to 3,000 FC. The commenters maintained 
that 2,100 FC does not align with their maintenance program intervals, 
which causes a significant burden on operators. United and American 
also stated that they have completed the inspection of 13 and 20 
airplanes respectively and found no evidence of cracking, which 
indicates that the existing 3,000 FC interval is conservative.
    The FAA disagrees with the requested change to the indicated 
repetitive inspection interval and initial interval. The FAA 
acknowledges that incorporating the interval into the existing 
maintenance program could be challenging for some operators. However, 
the inspection involves a visual assessment that requires limited 
disassembly and could be carried out without placing the aircraft in a 
heavy maintenance configuration. The reduced intervals are based on the 
re-assessment of the damage tolerance analysis to adjust for eleven 
additional crack findings since issuance of Boeing Alert Requirements 
Bulletin 757-57A0073 RB, dated July 14, 2017. The FAA has determined 
that the reduced inspection interval is necessary to avoid jeopardizing 
safety. The FAA has not changed the initial and repetitive inspection 
intervals required in this AD.

Request for Clarification That Compliance Times Cannot Be Extended

    Boeing requested that clarification be added to the proposed AD to 
specify that the grace period provided for the newly proposed 
requirements cannot be used to extend compliance times for actions 
required by AD 2018-16-05. Boeing suggested that the FAA add a new 
paragraph to the proposed AD that would explicitly re-state the 
requirements of AD 2018-16-05. Boeing asserted that the new paragraph 
would maintain the requirements of AD 2018-16-05 only until the actions 
of paragraph (g) of the proposed AD are implemented.
    The FAA does not agree to restate the requirements of AD 2018-16-05 
or to add a new paragraph regarding the compliance time for the 
previously required actions. As explained in the NPRM, the requirements 
of AD 2018-16-05 are referenced in the service information required in 
this AD. Except for the diagonal brace inspections, the compliance 
times given in Boeing Alert Requirements Bulletin 757-57A0073 RB, 
Revision 1, dated August 1, 2019, for all actions required by AD 2018-
16-05 are unchanged. The compliance times are defined both in terms of 
the effective date of AD 2018-16-05 and the effective date of the 
service information. For the diagonal brace inspections, the compliance 
time may provide an additional grace period; however, this affects only 
one inspection cycle, is applicable to a small number of operators, and 
is an acceptable compliance time to ensure safety. The FAA has 
determined all other compliance times will ensure an acceptable level 
of safety. This AD has not been changed in this regard.

[[Page 79420]]

Requests To Clarify the Effective Date of AD 2018-16-05

    American and Boeing requested that the proposed AD be revised to 
include clarification of the effective date of AD 2018-16-05. The 
commenters observed that some compliance times are given as the number 
of flight cycles after the ``effective date of AD 2018-16-05,'' and 
that where Boeing Alert Requirements Bulletin 757-57A0073 RB, dated 
July 14, 2017, uses that phrase, the proposed AD should require using 
``September 10, 2018.'' American asserted that the compliance times 
should be in terms of the date, not of the superseded AD, and that 
determining the effective date of the replaced AD could be difficult 
otherwise. The commenters asserted that including this clarification in 
the new AD would avoid confusion for operators.
    The FAA agrees to clarify the effective date of AD 2018-16-05. The 
FAA has added an exception in paragraph (h)(3) to indicate that, where 
Boeing Alert Requirements Bulletin 757-57A0073 RB, Revision 1, dated 
August 1, 2019, uses the phrase ``the effective date of AD 2018-16-
05,'' this AD requires using ``September 10, 2018 (the effective date 
of AD 2018-16-05).''

Requests To Give Credit for Previously Accomplished Actions

    American, Boeing, and FedEx requested that the proposed AD give 
credit for previously accomplished actions that were similar to or the 
same as the actions specified in Boeing Alert Requirements Bulletin 
757-57A0073 RB, Revision 1, dated August 1, 2019. American noted that 
Revision 1 of the service bulletin specifies a high frequency eddy 
current (HFEC) inspection for cracking at fastener locations 11-18 for 
airplanes already inspected in accordance with the original issue of 
the service bulletin. American and Boeing asserted that operators of 
airplanes with fastener holes 1-10 already inspected per Boeing Alert 
Requirements Bulletin 757-57A0073 RB, dated July 14, 2017, should get 
credit for the initial inspection of fastener holes 1-10.
    The FAA agrees and has added paragraph (i) to this AD to provide 
credit for previous actions accomplished using Boeing Alert 
Requirements Bulletin 757-57A0073 RB, dated July 14, 2017. The FAA has 
also reidentified subsequent paragraphs accordingly. As specified in 
Boeing Alert Requirements Bulletin 757-57A0073 RB, Revision 1, dated 
August 1, 2019, the new actions for fastener locations 11-18 must still 
be accomplished for airplanes on which the original revision of the RB 
was previously done.

Requests To Allow Certain AMOCs Previously Approved for AD 2018-16-05

    American, Delta Air Lines, FedEx, and United requested that the 
proposed AD be changed to allow AMOCs previously approved for AD 2018-
16-05 for the corresponding requirements of this AD. American, FedEx, 
and United observed that the inspections specified in Boeing Alert 
Requirements Bulletin 757-57A0073 RB, dated July 14, 2017, relating to 
fastener locations 1-10, as well as the repetitive inspections for 
these locations, do not change with Boeing Alert Requirements Bulletin 
757-57A0073 RB, Revision 1, dated August 1, 2019. The commenters 
asserted that the repairs and corresponding AMOCs should continue to be 
acceptable.
    The FAA agrees with the requested change. The FAA has changed 
paragraph (j)(4) of this AD (referred to as paragraph (i)(4) in the 
proposed AD) to specify that AMOCs granted to AD 2018-16-05 are 
acceptable as AMOCs to this AD for the corresponding requirements.

Conclusion

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

Related IBR Material Under 1 CFR Part 51

    The FAA reviewed Boeing Alert Requirements Bulletin 757-57A0073 RB, 
Revision 1, dated August 1, 2019. This service information describes 
procedures for repetitive inspections, including general visual, 
detailed, and HFEC inspections, for loose fasteners, skin cracking, and 
shim migration at the upper link drag fittings and for cracking in the 
diagonal brace and diagonal brace fittings and applicable on-condition 
actions. 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

    The FAA estimates that this AD affects 561 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                      Estimated Costs For Required Actions
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
              Action                    Labor cost        Parts cost      Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Repetitive inspections (retained   83 work-hours x $85              $0  $7,055 per           $3,957,855 per
 actions from AD 2018-16-05).       per hour = $7,055                    inspection cycle.    inspection cycle.
                                    per inspection
                                    cycle.
Repetitive HFEC inspections (new   2 work-hours x $85                0  $170 per inspection  $95,370 per
 action).                           per hour = $170                      cycle.               inspection cycle.
                                    per inspection
                                    cycle.
----------------------------------------------------------------------------------------------------------------

    The FAA has received no definitive data that would enable the 
agency to provide cost estimates 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.
    The FAA is 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.

[[Page 79421]]

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

    The FAA has 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) Will not affect intrastate aviation in Alaska, and
    (3) 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) 
2018-16-05, Amendment 39-19345 (83 FR 38250, August 6, 2018), and 
adding the following new AD:

2020-21-17 The Boeing Company: Amendment 39-21290; Docket No. FAA-
2019-0984; Product Identifier 2019-NM-161-AD.

(a) Effective Date

    This AD is effective January 14, 2021.

(b) Affected ADs

    This AD replaces AD 2018-16-05, Amendment 39-19345 (83 FR 38250, 
August 6, 2018) (``AD 2018-16-05'').

(c) Applicability

    (1) This AD applies to all The Boeing Company Model 757-200, -
200PF, -200CB, and -300 series airplanes, certificated in any 
category.
    (2) Installation of Supplemental Type Certificate (STC) 
ST01518SE does not affect the ability to accomplish the actions 
required by this AD. Therefore, for airplanes on which STC ST01518SE 
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

    Air Transport Association (ATA) of America Code 57, Wings.

(e) Unsafe Condition

    This AD was prompted by reports of bolt rotation in the engine 
drag fitting joint and fastener heads; an inspection of the fastener 
holes revealed that cracks were found in the skin. This AD was also 
prompted by a report of multiple cracks found in the drag fitting at 
fastener holes during inspections required by AD 2018-16-05. The FAA 
is issuing this AD to address cracking in the wing upper skin and 
forward drag fittings, which could lead to a compromised upper link 
and reduced structural integrity of the engine strut.

(f) Compliance

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

(g) Required Actions

    Except as specified by paragraph (h) of this AD: At the 
applicable times specified in the ``Compliance'' paragraph of Boeing 
Alert Requirements Bulletin 757-57A0073 RB, Revision 1, dated August 
1, 2019, do all applicable actions identified in, and in accordance 
with, the Accomplishment Instructions of Boeing Alert Requirements 
Bulletin 757-57A0073 RB, Revision 1, dated August 1, 2019.

    Note 1 to paragraph (g):  Guidance for accomplishing the actions 
required by this AD can be found in Boeing Alert Service Bulletin 
757-57A0073, Revision 1, dated August 1, 2019, which is referred to 
in Boeing Alert Requirements Bulletin 757-57A0073 RB, Revision 1, 
dated August 1, 2019.

(h) Exceptions to Service Information Specifications

    (1) Where Boeing Alert Requirements Bulletin 757-57A0073 RB, 
Revision 1, dated August 1, 2019, uses the phrase ``the Revision 1 
date of Requirements Bulletin 757-57A0073 RB,'' this AD requires 
using ``the effective date of this AD.''
    (2) Where Boeing Alert Requirements Bulletin 757-57A0073 RB, 
Revision 1, dated August 1, 2019, specifies contacting Boeing for 
repair instructions: This AD requires doing the repair and 
applicable on-condition actions before further flight using a method 
approved in accordance with the procedures specified in paragraph 
(j) of this AD.
    (3) Where Boeing Alert Requirements Bulletin 757-57A0073 RB, 
Revision 1, dated August 1, 2019, uses the phrase ``the effective 
date of AD 2018-16-05,'' this AD requires using ``September 10, 2018 
(the effective date of AD 2018-16-05).''

(i) Credit for Previous Actions

    This paragraph provides credit for the actions specified in 
paragraph (g) of this AD, except for the open-hole high frequency 
eddy current inspections at fastener locations 11-18, if those 
actions were performed before the effective date of this AD using 
Boeing Alert Requirements Bulletin 757-57A0073 RB, dated July 14, 
2017.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles ACO Branch, 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 certification office, send it to the attention of 
the person identified in paragraph (k)(1) of this AD. Information 
may be emailed to: <a href="/cdn-cgi/l/email-protection#467f6b07080b6b0a070705096b070b09056b14233733233532350620272768212930"><span class="__cf_email__" data-cfemail="665f4b27282b4b2a272725294b272b29254b34031713031512152600070748010910">[email&#160;protected]</span></a>.
    (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, modification, or alteration required by this AD 
if it is approved by The Boeing Company Organization Designation 
Authorization (ODA) that has been authorized by the Manager, Los 
Angeles ACO Branch, FAA, to make those findings. To be approved, the 
repair method, modification deviation, or alteration deviation must 
meet the certification basis of the airplane, and the approval must 
specifically refer to this AD.
    (4) AMOCs approved previously for AD 2018-16-05 are approved as 
AMOCs for the corresponding provisions of Boeing Alert Requirements 
Bulletin 757-57A0073 RB, Revision 1, dated August 1, 2019, that are 
required by paragraph (g) of this AD.

(k) Related Information

    (1) For more information about this AD, contact Chandra Ramdoss, 
Aerospace Engineer, Airframe Section, FAA, Los Angeles ACO Branch, 
3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: 562-627-
5239; fax: 562-627-5210; email: <a href="/cdn-cgi/l/email-protection#dfbcb7beb1bbadbebbaaabb7f1adbeb2bbb0acac9fb9bebef1b8b0a9"><span class="__cf_email__" data-cfemail="4e2d262f202a3c2f2a3b3a26603c2f232a213d3d0e282f2f60292138">[email&#160;protected]</span></a>.
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (l)(3) and (4) of this AD.

(l) 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 Alert Requirements Bulletin 757-57A0073 RB, Revision 
1, dated August 1, 2019.
    (ii) [Reserved]
    (3) For service information identified in this AD, contact 
Boeing Commercial

[[Page 79422]]

Airplanes, Attention: Contractual & Data Services (C&DS), 2600 
Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; telephone 
562-797-1717; internet <a href="https://www.myboeingfleet.com">https://www.myboeingfleet.com</a>.
    (4) You may view this service information at the FAA, 
Airworthiness Products Section, Operational Safety Branch, 2200 
South 216th St., Des Moines, WA. For information on the availability 
of this material at the FAA, call 206-231-3195.
    (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, email <a href="/cdn-cgi/l/email-protection#b9dfdcddcbdcde97d5dcded8d5f9d7d8cbd897ded6cf"><span class="__cf_email__" data-cfemail="422427263027256c2e2725232e022c2330236c252d34">[email&#160;protected]</span></a>, or go to: <a href="https://www.archives.gov/federal-register/cfr/ibr-locations.html">https://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.

    Issued on October 7, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2020-27007 Filed 12-9-20; 8:45 am]
BILLING CODE 4910-13-P