This section of the FEDERAL REGISTER

contains notices to the public of the proposed

issuance of rules and regulations. The

purpose of these notices is to give interested

persons an opportunity to participate in the

rule making prior to the adoption of the final

rules.

Proposed Rules Federal Register

2515 

Vol. 89, No. 10 

Tuesday, January 16, 2024 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2024–0028; Project 

Identifier AD–2023–00919–T] 

RIN 2120–AA64 

Airworthiness Directives; The Boeing 

Company Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: The FAA proposes to 

supersede Airworthiness Directive (AD) 

2021–09–06, which applies to all The 

Boeing Company Model 737–600, –700, 

–700C, –800, –900, and –900ER series 

airplanes. AD 2021–09–06 requires 

repetitive inspections for cracking of the 

left- and right-hand side outboard 

chords of certain frame fittings and 

failsafe straps at a certain station around 

eight fasteners, and repair if any 

cracking is found. Since the FAA issued 

AD 2021–09–06, additional reports of 

cracking in the area were received and 

it was determined that additional 

inspections are needed to address the 

unsafe condition. This proposed AD 

would require repetitive detailed and 

ultrasonic inspections for cracking of 

the left-and right-hand sides of certain 

frame fittings and failsafe straps, and 

repair if any cracking is found. 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 1, 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–2024–0028; 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. 

Material Incorporated by Reference: 

• 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; website 

myboeingfleet.com. 

• 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 at 

regulations.gov by searching for and 

locating Docket No. FAA–2024–0028. 

FOR FURTHER INFORMATION CONTACT: 

Owen Bley-Male, Aviation Safety 

Engineer, FAA, 2200 South 216th St., 

Des Moines, WA 98198; telephone 206– 

231–3992; email owen.f.bley-male@

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 ADDRESSES. Include ‘‘Docket No. 

FAA–2024–0028; Project Identifier AD– 

2023–00919–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 Owen Bley-Male, 

Aviation Safety Engineer, FAA, 2200 

South 216th St., Des Moines, WA 98198; 

telephone 206–231–3992; email 

owen.f.bley-male@faa.gov. 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 issued AD 2021–09–06, 

Amendment 39–21519 (86 FR 23595, 

May 4, 2021) (AD 2021–09–06), for all 

The Boeing Company Model 737–600, 

–700, –700C, –800, –900, and –900ER 

series airplanes. AD 2021–09–06 was 

prompted by reports of cracking 

discovered in the station (STA) 663.75 

frame fitting outboard chords and 

failsafe straps adjacent to the stringer S– 

18A straps and a determination that the 

initial inspection threshold and 

repetitive inspection interval required 

by AD 2019–22–10, Amendment 39– 

19789 (84 FR 61533, November 13, 

2019), were inadequate to address 

cracking in a timely manner. AD 2021– 

09–06 requires repetitive inspections for 

cracking of the left- and right-hand side 

outboard chords of frame fittings and 

failsafe straps at a certain station around 

eight fasteners, repair if any cracking is 


ddrumheller on DSK120RN23PROD with PROPOSALS1
2516 Federal Register / Vol. 89, No. 10 / Tuesday, January 16, 2024 / Proposed Rules 

found, and an inspection report. The 

agency issued AD 2021–09–06 to 

address cracking in the STA 663.75 

frame fitting outboard chords and 

failsafe straps adjacent to the stringer S– 

18A straps, which could result in failure 

of a principal structural element (PSE) 

to sustain limit load. This condition 

could adversely affect the structural 

integrity of the airplane and result in 

loss of control of the airplane. 

Actions Since AD 2021–09–06 Was 

Issued 

Since the FAA issued AD 2021–09– 

06, additional reports have been made 

of several cracks in the STA 663.75 

frame fittings and failsafe straps. Cracks 

have also been found at the aft fastener 

common to the failsafe strap upper row. 

Several cracks in the frame fitting were 

found extending beyond the aft fastener 

hole to the forward fastener hole. An 

additional report was made of a visible 

crack in the failsafe strap without any 

visibly detectable crack in the frame 

fitting. These additional reports led to a 

determination that the detailed visual 

inspection required by AD 2021–09–06 

might not be adequate to detect STA 

663.75 failsafe strap cracking. 

Additionally, the preamble to AD 

2021–09–06 explained that the FAA 

considered the requirements ‘‘interim 

action’’ and was considering further 

rulemaking. The FAA has now 

determined that further rulemaking is 

indeed necessary and this proposed AD 

follows from that determination. 

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 737–53A1414 

RB, Revision 1, dated November 20, 

2023. This service information specifies 

procedures for repetitive internal 

detailed inspection for cracking of the 

frame fitting and visible areas of the 

failsafe strap at STA 663.73 (left- and 

right-hand sides), repetitive external 

detailed and ultrasonic inspections for 

cracking of the failsafe strap at STA 

663.75 (left- and right-hand sides), and 

repair if any cracking is found. 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 

Although this proposed AD does not 

explicitly restate the requirements of AD 

2021–09–06, this proposed AD would 

retain the inspection requirements of 

AD 2021–09–06. Those requirements are 

referenced in the service information 

identified previously, which, in turn, is 

referenced in paragraph (g) of this 

proposed AD. 

This proposed AD would require 

accomplishing the actions specified in 

the service information 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 service 

information at regulations.gov under 

Docket No. FAA–2024–0028. 

Costs of Compliance 

The FAA estimates that this AD, if 

adopted as proposed, would affect 1,911 

airplanes of U.S. registry. The FAA 

estimates the following costs to comply 

with this proposed AD: 

ESTIMATED COSTS

Action Labor cost Parts cost Cost per product Cost on U.S. operators 

Inspection ............................... 4 work-hours × $85 per hour 

= $340 per inspection cycle.

$0 $340 per inspection cycle ...... $649,740 per inspection 

cycle. 

The FAA has received no definitive 

data on which to base the cost estimates 

for the on-condition repairs specified in 

this proposed AD. 

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 

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 

■ 1. The authority citation for part 39 

continues to read as follows: 

Authority: 49 U.S.C. 106(g), 40113, 44701. 

§ 39.13 [Amended] 

■ 2. The FAA amends § 39.13 by: 


ddrumheller on DSK120RN23PROD with PROPOSALS1
Federal Register / Vol. 89, No. 10 / Tuesday, January 16, 2024 / Proposed Rules 2517 

■ a. Removing Airworthiness Directive 

(AD) 2021–09–06, Amendment 39– 

21519 (86 FR 23595, May 4, 2021), and 

■ b. Adding the following new AD: 

The Boeing Company: Docket No. FAA– 

2024–0028; Project Identifier AD–2023– 

00919–T. 

(a) Comments Due Date 

The FAA must receive comments on this 

airworthiness directive (AD) by March 1, 

2024. 

(b) Affected ADs 

This AD replaces AD 2021–09–06, 

Amendment 39–21519 (86 FR 23595, May 4, 

2021) (AD 2021–09–06). 

(c) Applicability 

This AD applies to all The Boeing 

Company Model 737–600, –700, –700C, 

–800, –900, and –900ER 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 

cracking in the station (STA) 663.75 frame 

fitting outboard chords and failsafe straps 

adjacent to the stringer S–18A area and a 

determination that additional inspections are 

needed to address the unsafe condition. The 

FAA is issuing this AD to address cracking 

in the STA 663.75 frame fitting outboard 

chords and failsafe straps adjacent to the 

stringer S–18A straps, which could result in 

failure of a Principal Structural Element 

(PSE) to sustain limit load. The unsafe 

condition, if not addressed, could adversely 

affect the structural integrity of the airplane 

and result in loss of control 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 737–53A1414 RB, 

Revision 1, dated November 20, 2023, do all 

applicable actions identified in, and in 

accordance with, the Accomplishment 

Instructions of Boeing Alert Requirements 

Bulletin 737–53A1414 RB, Revision 1, dated 

November 20, 2023. 

Note 1 to paragraph (g): Guidance for 

accomplishing the actions required by this 

AD can be found in Boeing Alert Service 

Bulletin 737–53A1414, Revision 1, dated 

November 20, 2023, which is referred to in 

Boeing Alert Requirements Bulletin 737– 

53A1414 RB, Revision 1, dated November 20, 

2023. 

(h) Exceptions to Service Information 

Specifications 

(1) Where the Condition and Compliance 

Time columns of the tables in the 

‘‘Compliance’’ paragraph of Boeing Alert 

Requirements Bulletin 737–53A1414 RB, 

Revision 1, dated November 20, 2023, use the 

phrase ‘‘the original issue date of 

Requirements Bulletin 737–53A1414 RB,’’ or 

‘‘the Revision 1 date of Requirements 

Bulletin 737–53A1414 RB,’’ this AD requires 

using ‘‘the effective date of this AD.’’ 

(2) Where Boeing Alert Requirements 

Bulletin 737–53A1414 RB, Revision 1, dated 

November 20, 2023, 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: 9-ANMSeattle-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 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 Owen Bley-Male, Aviation Safety 

Engineer, FAA, 2200 South 216th St., Des 

Moines, WA 98198; telephone 206–231– 

3992; email owen.f.bley-male@faa.gov. 

(2) Service information identified in this 

AD that is not incorporated by reference is 

available at the addresses specified in 

paragraphs (k)(3) and (4) of this AD. 

(k) 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 this AD specifies otherwise. 

(i) Boeing Alert Requirements Bulletin 

737–53A1414 RB, Revision 1, dated 

November 20, 2023. 

(ii) [Reserved] 

(3) 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; website 

myboeingfleet.com. 

(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 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 fr.inspection@nara.gov. 

Issued on January 5, 2024. 

Victor Wicklund, 

Deputy Director, Compliance & Airworthiness 

Division, Aircraft Certification Service. 

[FR Doc. 2024–00345 Filed 1–12–24; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 39 

[Docket No. FAA–2024–0031; Project 

Identifier MCAI–2022–01307–T] 

RIN 2120–AA64 

Airworthiness Directives; MHI RJ 

Aviation ULC (Type Certificate 

Previously Held by Bombardier, Inc.) 

Airplanes 

AGENCY: Federal Aviation 

Administration (FAA), DOT. 

ACTION: Notice of proposed rulemaking 

(NPRM). 

SUMMARY: The FAA proposes to adopt a 

new airworthiness directive (AD) for 

certain MHI RJ Aviation ULC Model 

CL–600–2C10 (Regional Jet Series 700, 

701 & 702); CL–600–2C11 (Regional Jet 

Series 550); CL–600–2D15 (Regional Jet 

Series 705); and CL–600–2D24 (Regional 

Jet Series 900) airplanes. This proposed 

AD was prompted by a determination 

that a potential crack of the tombstone 

fitting lug cannot be detected as the 

bushings remaining in place during 

accomplishment of the special detailed 

inspection (SDI) required by a certain 

airworthiness limitation (ALI) task. This 

proposed AD would require inspecting 

the tombstone fitting lug with a new SDI 

sub-surface ultrasound procedure when 

accomplishing the ALI task, as specified 

in a Transport Canada AD, which is 

proposed for incorporation by reference 

(IBR). This proposed AD would also 

require corrective actions if necessary. 

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 1, 2024. 


ddrumheller on DSK120RN23PROD with PROPOSALS1