[Federal Register Volume 89, Number 128 (Wednesday, July 3, 2024)]
[Proposed Rules]
[Pages 55128-55130]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-14608]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-1882; Project Identifier AD-2024-00227-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 certain 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, 
747SP, and 747SR series airplanes. This proposed AD was prompted by a 
report indicating cracks at eight fastener hole locations in the 
fuselage skin lap splice between certain stations (STAs) at certain 
stringers. This proposed AD would require repetitive inspections of the 
upper fastener row of the fuselage skin lap splice in a certain area 
for any crack, 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 19, 
2024.

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 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.
    AD Docket: You may examine the AD docket at regulations.gov under 
Docket No. FAA-2024-1882; or in person at

[[Page 55129]]

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.
    Material Incorporated by Reference:
     For the material, 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; website 
myboeingfleet.com.
     You may view this material 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 regulations.gov under 
Docket No. FAA-2024-1882.

FOR FURTHER INFORMATION CONTACT: Stefanie Roesli, Aviation Safety 
Engineer, FAA, 2200 South 216th St., Des Moines, WA 98198; phone: 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 the ADDRESSES section. Include ``Docket No. FAA-2024-1882; 
Project Identifier AD-2024-00227-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 
regulations.gov, including any personal information you provide. The 
agency will also post a report 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, Aviation Safety Engineer, FAA, 2200 South 216th St., 
Des Moines, WA 98198; phone: 206-231-3964; email: 
[email protected]. Any commentary that the FAA receives that is 
not specifically designated as CBI will be placed in the public docket 
for this rulemaking.

Background

    The FAA has received a report that cracking was found at eight 
fastener hole locations in the fuselage skin lap splice between STAs 
1450 and 1470 at stringers S-23L and S-23R on a Boeing Model 747-400 
series airplane that had completed 128,792 flight hours and 25,581 
flight cycles when the cracks were discovered. The maximum crack length 
discovered was 0.946 inch. After this report was received, the Boeing 
Company did a high frequency eddy current inspection on the Boeing 
Model 747-100 fatigue test airplane and found cracks on the countersink 
area of the fastener holes on the lap splice between STAs 1416 and 1480 
at stringers S-23L and S-23R. The maximum crack length discovered was 
0.10 inch. The Boeing Model 747-100 fatigue test airplane had completed 
the equivalent of 45,000 flight cycles. Cracking in the fuselage skin 
lap splice, if not addressed, could result in an in-flight rapid 
decompression and a loss of structural integrity of the fuselage.

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 Material Under 1 CFR Part 51

    The FAA reviewed Boeing Alert Requirements Bulletin 747-53A2912 RB, 
dated April 5, 2024. This material specifies procedures for repetitive 
external surface high frequency eddy current inspections of the upper 
fastener row of the fuselage skin lap splice between STAs 1350 and 1480 
at stringers S-23L and S-23R for any crack, and applicable on-condition 
actions. On-condition actions include obtaining and following repair 
instructions.
    This material 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.

Proposed AD Requirements in This NPRM

    This proposed AD would require accomplishing the actions specified 
in the material already described, 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 
material at regulations.gov under Docket No. FAA-2024-1882.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 170 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
----------------------------------------------------------------------------------------------------------------
Inspections......................  8 work-hours x $85               $0  $680 per inspection  $115,600 per
                                    per hour = $680                      cycle.               inspection cycle
                                    per inspection
                                    cycle.
----------------------------------------------------------------------------------------------------------------

    The FAA has received no definitive data on which to base the 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.

[[Page 55130]]

    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-2024-1882; Project Identifier AD-
2024-00227-T.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by August 19, 2024.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to 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, 747SP, and 747SR series airplanes, certificated in 
any category, as identified in Boeing Alert Requirements Bulletin 
747-53A2912 RB, dated April 5, 2024.

(d) Subject

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

(e) Unsafe Condition

    This AD was prompted by a report indicating cracks at eight 
fastener hole locations in the fuselage skin lap splice between 
stations (STAs) 1450 and 1470 at stringers S-23L and S-23R. The FAA 
is issuing this AD to detect and correct cracking of the upper 
fastener row of the fuselage skin lap splice between STAs 1350 and 
1480 at stringers S-23L and S-23R. The unsafe condition, if not 
addressed, could result in an in-flight rapid decompression and a 
loss of structural integrity of the fuselage.

(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 747-53A2912 RB, dated April 5, 2024, do 
all applicable actions identified in, and in accordance with, the 
Accomplishment Instructions of Boeing Alert Requirements Bulletin 
747-53A2912 RB, dated April 5, 2024.

    Note 1 to paragraph (g):  Guidance for accomplishing the actions 
required by this AD can be found in Boeing Alert Service Bulletin 
747-53A2912, dated April 5, 2024, which is referred to in Boeing 
Alert Requirements Bulletin 747-53A2912 RB, dated April 5, 2024.

(h) Exceptions to Service Information Specifications

    (1) Where the Condition and Boeing Recommended Compliance Time 
columns of the tables in the ``Compliance'' paragraph of Boeing 
Alert Requirements Bulletin 747-53A2912 RB, dated April 5, 2024, 
refer to ``the Original Issue date of the Requirements Bulletin 747-
53A2912 RB,'' this AD requires using the effective date of this AD.
    (2) Where Boeing Alert Requirements Bulletin 747-53A2912 RB, 
dated April 5, 2024, specifies contacting Boeing for repair 
instructions: This AD requires doing the repair 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, AIR-520, Continued Operational Safety 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, AIR-
520, Continued Operational Safety 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, 
Aviation Safety Engineer, FAA, 2200 South 216th St., Des Moines, WA 
98198; phone: 206-231-3964; email: [email protected].
    (2) Material identified in this AD that is not incorporated by 
reference is available at the address specified in paragraph (k)(3) 
this AD.

(k) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the material listed in this 
paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this material as applicable to do the actions 
required by this AD, unless the AD specifies otherwise.
    (i) Boeing Alert Requirements Bulletin 747-53A2912 RB, dated 
April 5, 2024.
    (ii) [Reserved]
    (3) For Boeing material, 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; website myboeingfleet.com.
    (4) You may view this material 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 material at the National Archives and 
Records Administration (NARA). For information on the availability 
of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email [email protected].

    Issued on June 27, 2024.
Suzanne Masterson,
Deputy Director, Integrated Certificate Management Division, Aircraft 
Certification Service.
[FR Doc. 2024-14608 Filed 7-2-24; 8:45 am]
BILLING CODE 4910-13-P