[Federal Register Volume 87, Number 20 (Monday, January 31, 2022)]
[Proposed Rules]
[Pages 4826-4828]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-01860]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-1173; Project Identifier AD-2021-00917-T]
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 747-8F series airplanes. This proposed 
AD was prompted by reports of fuselage crown stringer cracking between 
station (STA) 740 and STA 1000, stringer (S)-7 to S-12. This proposed 
AD would require repetitive detailed inspections for cracking of 
fuselage crown stringers 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 March 17, 
2022.

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 at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-
1173.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2021-1173; 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.

FOR FURTHER INFORMATION CONTACT: Stefanie Roesli, Aerospace Engineer, 
Airframe Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des 
Moines, WA 98198; phone and fax: 206-231-3964; email: 
[email protected].

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 ADDRESSES. Include ``Docket No. FAA-2021-1173; Project Identifier 
AD-2021-00917-T'' at the beginning of your comments. The most helpful 
comments reference a specific portion of the proposal, explain the 
reason for any recommended change, and include supporting data. The FAA 
will consider all comments received by the closing date and may amend 
this proposal because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
https://www.regulations.gov, including any personal information you 
provide. The agency will also post a report

[[Page 4827]]

summarizing each substantive verbal contact received about this NPRM.

Confidential Business Information

    CBI is commercial or financial information that is both customarily 
and actually treated as private by its owner. Under the Freedom of 
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public 
disclosure. If your comments responsive to this NPRM contain commercial 
or financial information that is customarily treated as private, that 
you actually treat as private, and that is relevant or responsive to 
this NPRM, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and they will not be placed in the public 
docket of this NPRM. Submissions containing CBI should be sent to 
Stefanie Roesli, Aerospace Engineer, Airframe Section, FAA, Seattle ACO 
Branch, 2200 South 216th St., Des Moines, WA 98198; phone and fax: 206-
231-3964; email: [email protected]. Any commentary that the FAA 
receives which is not specifically designated as CBI will be placed in 
the public docket for this rulemaking.

Background

    The FAA has received reports of fuselage crown stringer cracking 
located on the left and right sides at S-7, S-8, S-9, S-10, S-11, and 
S-12, between STA 740 and STA 1000. Some of these reports were made 
during airplane production, and others were found on airplanes 
currently in operation. The existing maintenance inspections cannot 
reliably detect cracking at multiple stringers and bay frames. Any 
crack in these locations must be found and repaired before reaching a 
critical length. Without an inspection, any crack may grow in length 
and go undetected. This condition, if not addressed, could result in 
the inability of a structural element to sustain limit load, and could 
adversely affect the structural integrity of the airplane.

FAA's Determination

    The FAA is issuing this NPRM after determining that the unsafe 
condition described previously is likely to exist or develop on other 
products of the same type design.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Boeing Alert Requirements Bulletin 747-53A2906 RB, 
dated July 16, 2021. This service information specifies procedures for 
repetitive detailed inspections for cracking of fuselage crown 
stringers, repair of cracks, and a high frequency eddy current (HFEC) 
inspection for cracking of repaired areas. 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 
ADDRESSES.

Proposed AD Requirements in This NPRM

    This proposed AD would require accomplishing the actions specified 
in the service information already described, except as discussed under 
``Difference Between this Proposed AD and the Service Information'' and 
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-2021-
1173.

Clarification of Proposed Inspection Requirements

    Table 1 of Boeing Alert Requirements Bulletin 747-53A2906 RB, dated 
July 16, 2021, specifies repetitive detailed inspections to detect 
cracking of the side crown stringers on all airplanes. Table 1 of the 
service information does not specifically state that airplanes with no 
crack found (``Condition 1'') may have additional work. However, for 
airplanes with Condition 1 that have any repairs in the inspection 
area, the HFEC inspection specified in Table 2 of the service 
information would also be required.

Difference Between This Proposed AD and the Service Information

    The applicability in this proposed AD does not refer to paragraph 
1., ``Effectivity,'' of Boeing Alert Requirements Bulletin 747-53A2906 
RB, dated July 16, 2021, because this service information does not 
contain a comprehensive list of the airplanes affected by the 
identified unsafe condition. Therefore, the applicability of this 
proposed AD is all Model 747-8F series airplanes.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 33 airplanes of U.S. registry. The FAA estimates the following 
costs to comply with this proposed AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                 Cost on U.S.
              Action                    Labor cost        Parts cost      Cost per product        operators
----------------------------------------------------------------------------------------------------------------
Repetitive detailed inspections..  84 work-hours x $85              $0  $7,140 per           $235,620 per
                                    per hour = $7,140                    inspection cycle.    inspection cycle.
                                    per inspection
                                    cycle.
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any necessary repairs 
that would be required based on the results of the proposed inspection. 
The agency has no way of determining the number of aircraft that might 
need these repairs:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
             Action                         Labor cost             Parts cost            Cost per product
----------------------------------------------------------------------------------------------------------------
HFEC inspection.................  1 work-hour x $85 per hour =               $0  $85.
                                   $85.
Repair..........................  Up to 550 work-hours x $85              2,400  Up to $49,150.
                                   per hour = $46,750 (per
                                   repaired area).
----------------------------------------------------------------------------------------------------------------

    The FAA has included all known costs in its cost estimate. 
According to the manufacturer, however, some or all of the costs of 
this proposed AD may be covered under warranty, thereby reducing the 
cost impact on affected operators.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue

[[Page 4828]]

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) Would not affect intrastate aviation in Alaska, and
    (3) Would 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:

The Boeing Company: Docket No. FAA-2021-1173; Project Identifier AD-
2021-00917-T.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by March 17, 2022.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model 747-8F series 
airplanes, certificated in any category.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by reports of fuselage crown stringer 
cracking between STA 740 and STA 1000, S-7 to S-12. The FAA is 
issuing this AD to address cracking in fuselage crown stringers. 
This condition, if not addressed, could result in the inability of a 
structural element to sustain limit load, and could adversely affect 
the structural integrity of the airplane.

(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 747-53A2906 RB, dated July 16, 2021, do 
all applicable actions identified in, and in accordance with, the 
Accomplishment Instructions of Boeing Alert Requirements Bulletin 
747-53A2906 RB, dated July 16, 2021.
    Note 1 to paragraph (g): Guidance for accomplishing the actions 
required by this AD can be found in Boeing Alert Service Bulletin 
747-53A2906, dated July 16, 2021, which is referred to in Boeing 
Alert Requirements Bulletin 747-53A2906 RB, dated July 16, 2021.

(h) Exception to Service Information Specifications

    Where the Compliance Time columns of the tables in the 
``Compliance'' paragraph of Boeing Alert Requirements Bulletin 747-
53A2906 RB, dated July 16, 2021, use the phrase ``the original issue 
date of Requirements Bulletin 747-53A2906 RB,'' this AD requires 
using ``the effective date 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 responsible Flight Standards 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: [email protected].
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the responsible Flight Standards 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 Stefanie Roesli, 
Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 2200 
South 216th St., Des Moines, WA 98198; phone and fax: 206-231-3964; 
email: [email protected].
    (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 December 29, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2022-01860 Filed 1-28-22; 8:45 am]
BILLING CODE 4910-13-P