[Federal Register Volume 85, Number 126 (Tuesday, June 30, 2020)]
[Proposed Rules]
[Pages 39108-39110]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-13973]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0573; Product Identifier 2020-NM-078-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt 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 proposed AD was prompted by a 
determination that the upper wing skin at engine nacelle points may be 
subject to undetected cracking. This proposed AD would require 
repetitive ultrasonic inspections of the upper wing skin at certain 
engine strut positions for cracking; repetitive detailed and ultrasonic 
inspections of the strut lower spar fitting, diagonal brace strut end 
clevis, and diagonal brace wing attach end clevis for cracking; 
repetitive detailed inspections of lower link fitting at certain engine 
strut positions for cracking; and applicable on-condition actions. The 
FAA is proposing this AD to address the unsafe condition on these 
products.

DATES: The FAA must receive comments on this proposed AD by August 14, 
2020.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to https://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 NPRM, contact Boeing 
Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 
2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; 
telephone 562-797-1717; internet https://www.myboeingfleet.com. You may 
view this referenced 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 https://www.regulations.gov by searching for and locating Docket No. FAA-2020-
0573.

Examining the AD Docket

    You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-
0573; 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 NPRM, any comments received, and other information. The street 
address for Docket Operations is listed above. Comments will be 
available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Eric Lin, Aerospace Engineer, Airframe 
Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 
98198; phone and fax: 206-231-3523; email: eric.lin@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2020-0573; 
Product Identifier 2020-NM-078-AD'' at the beginning of your comments. 
The FAA specifically invites comments on the overall regulatory, 
economic, environmental, and energy aspects of this NPRM. The FAA will 
consider all comments received by the closing date and may amend this 
NPRM because of those comments.
    The FAA will post all comments received, without change, to https://www.regulations.gov, including any personal information you provide. 
The FAA will also post a report summarizing each substantive verbal 
contact received about this proposed AD.

Discussion

    The FAA has received a report indicating that the upper wing skin 
at engine nacelle points may be subject to undetected cracking. Safety 
service related problems found on a Model 757 airplane led to a cross-
model review of the upper wing skin at engine nacelle attach points and 
a revision to analysis criteria. The FAA has not received any reports 
of cracking on Model 747 airplanes, but existing inspections do not 
provide opportunities for crack detection prior to loss of residual 
strength in the fail-safe load path. Based on the findings for Model 
757 airplanes, Boeing identified that loss of clamp-up due to shim 
migration, cracked fastener heads, or loss of torque causes cracking of 
the fasteners and fastener holes and may lead to cracking of the upper 
wing skin. Undetected cracks in the upper wing skin, strut lower spar 
fitting, or clevis lugs at either end of the diagonal brace and lower 
link fitting, if not addressed, could adversely affect the structural 
integrity of the engine strut and may lead to the separation of the 
strut to wing box assembly.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Boeing Alert Requirements Bulletin 747-57A2363 RB, 
dated December 23, 2019. The service information describes procedures 
for ultrasonic inspections of the upper wing skin at engine strut 
positions 1 through 4 for cracking; detailed and ultrasonic inspections 
of the strut lower spar fitting, diagonal brace strut end clevis, and 
diagonal brace wing attach end clevis for cracking; detail inspections 
of lower link fitting at engine strut positions 1 through 4 for 
cracking; and applicable on-condition actions. On-condition actions 
include repair.
    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.

FAA's Determination

    The FAA is proposing this AD because the agency 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 require accomplishment of the actions 
identified in Boeing Alert Requirements Bulletin 747-57A2363 RB, 
Original issue, dated December 23, 2019,

[[Page 39109]]

described previously, except for any differences identified as 
exceptions in the regulatory text of this proposed AD.
    For information on the procedures and compliance times, see this 
service information at https://www.regulations.gov by searching for and 
locating Docket No. FAA-2020-0573.

Explanation of Requirements Bulletin

    The FAA worked in conjunction with industry, under the 
Airworthiness Directive Implementation Aviation Rulemaking Committee 
(AD ARC), to enhance the AD system. One enhancement is a process for 
annotating which steps in the service information are ``required for 
compliance'' (RC) with an AD. Boeing has implemented this RC concept 
into Boeing service bulletins.
    In an effort to further improve the quality of ADs and AD-related 
Boeing service information, a joint process improvement initiative was 
worked between the FAA and Boeing. The initiative resulted in the 
development of a new process in which the service information more 
clearly identifies the actions needed to address the unsafe condition 
in the ``Accomplishment Instructions.'' The new process results in a 
Boeing Requirements Bulletin, which contains only the actions needed to 
address the unsafe condition (i.e., only the RC actions).

Costs of Compliance

    The FAA estimates that this proposed AD affects 125 airplanes of 
U.S. registry. The FAA estimates the following costs to comply with 
this proposed AD:

                                                                              Estimated Costs for Required Actions
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           Action                      Labor cost                       Parts cost                              Cost per product                              Cost on U.S. operators
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Inspections.................  9 work-hours x $85 per hour   $0................................  $765 per inspection cycle......................  $95,625 per inspection cycle.
                               = $765 per inspection cycle.
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    The FAA has received no definitive data that would enable the 
agency to provide cost estimates 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.
    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. 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 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 this proposed 
regulation:
    (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.

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 adding the following new airworthiness 
directive (AD):

The Boeing Company: Docket No. FAA-2020-0573; Product Identifier 
2020-NM-078-AD.

(a) Comments Due Date

    The FAA must receive comments by August 14, 2020.

(b) Affected ADs

    None.

(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 57, Wings.

(e) Unsafe Condition

    This AD was prompted by a determination that the upper wing skin 
at engine nacelle attachment points may be subject to undetected 
cracking. The FAA is issuing this AD to address undetected cracking 
in the upper wing skin, strut lower spar fitting, or clevis lugs at 
either end of the diagonal brace and lower link fitting. This 
condition, if not addressed, could adversely affect the structural 
integrity of the engine strut and may lead to the separation of the 
strut to wing box assembly.

(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 747-57A2363 RB, dated December 23, 2019, 
do all applicable actions identified in, and in accordance with, the 
Accomplishment Instructions of Boeing Alert Requirements Bulletin 
747-57A2363 RB, dated December 23, 2019.

    Note 1 to paragraph (g):  Guidance for accomplishing the actions 
required by this AD can be found in Boeing Alert Service Bulletin 
747-57A2363, dated December 23, 2019, which is referred to in Boeing 
Alert Requirements Bulletin 747-57A2363 RB, dated December 23, 2019.

(h) Exceptions to Service Information Specifications

    (1) Where Boeing Alert Requirements Bulletin 747-57A2363 RB, 
dated December 23, 2019, uses the phrase ``the original issue

[[Page 39110]]

date of Requirements Bulletin 747-57A2363 RB,'' this AD requires 
using ``the effective date of this AD.''
    (2) Where Boeing Alert Requirements Bulletin 747-57A2363 RB, 
dated December 23, 2019, specifies contacting Boeing for repair 
instructions: This AD requires doing the repair before further 
flight using a method approved in accordance with the procedures 
specified in paragraph (i) of this AD.

(i) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle 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 (j)(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, 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, Seattle 
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.

(j) Related Information

    (1) For more information about this AD, contact Eric Lin, 
Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 2200 
South 216th St., Des Moines, WA 98198; phone and fax: 206-231-3523; 
email: eric.lin@faa.gov.
    (2) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Contractual & Data Services 
(C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-
5600; telephone 562-797-1717; internet https://www.myboeingfleet.com. You may view this referenced 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.

    Issued on June 15, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2020-13973 Filed 6-29-20; 8:45 am]
BILLING CODE 4910-13-P


