2024-08392. Airworthiness Directives; The Boeing Company Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Supplemental notice of proposed rulemaking (SNPRM).

SUMMARY:

The FAA is revising a notice of proposed rulemaking NPRM that would have applied to certain The Boeing Company Model 757-200, -200CB, and -200PF series airplanes. This action revises the NPRM by revising the compliance times for certain airplanes. The FAA is proposing this airworthiness directive (AD) to address the unsafe condition on these products. Since these actions would impose an additional burden over that in the NPRM, the FAA is requesting comments on this SNPRM.

DATES:

The FAA must receive comments on this SNPRM by June 6, 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: [phone].

• 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-2023-1053; 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 SNPRM, any comments received, and other information. The street address for Docket Operations is listed above.

Material Incorporated by Reference:

• 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 [phone]; 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 by searching for and locating Docket No. FAA-2023-1053.

FOR FURTHER INFORMATION CONTACT:

Wayne Ha, Aviation Safety Engineer, FAA, 2200 South 216th Street, Des Moines, WA 98198; phone: [phone]; email: [e-mail].

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-2023-1053; Project Identifier AD-2023-00164-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 again revise 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 proposed AD.

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 SNPRM 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 SNPRM, 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 SNPRM. Submissions containing CBI should be sent Wayne Ha, Aviation Safety Engineer, FAA, 2200 South 216th Street, Des Moines, WA 98198; phone: [phone]; email: [e-mail]. 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 an NPRM to amend 14 CFR part 39 by adding an AD that would apply to certain The Boeing Company Model 757-200, -200CB, and -200PF series airplanes. The NPRM published in the Federal Register on July 24, 2023 (88 FR 47402). The NPRM was prompted by a crack growth analysis, which indicated that current inspections are not adequate to detect cracks in certain sections of the upper frame at the frame splice between certain stringers before a single frame fails. In the NPRM, the FAA proposed to require an inspection or records review for existing repairs; repetitive inspections for cracks of the upper frame at the frame splices between certain stringers in certain sections, and applicable on-condition actions.

Actions Since the NPRM Was Issued

Since the FAA issued the NPRM, it was determined that the repetitive inspection intervals for airplanes that were modified by Aviation Partners Boeing (APB) supplemental type certificate (STC) ST01518SE need to be revised.

Comments

The FAA received comments from United Airlines who supported the NPRM without change.

The FAA received additional comments from APB, Federal Express (FedEx), Boeing, and United Parcel Service (UPS). The following presents the comments received on the NPRM and the FAA's response to each comment.

Limited Organization Designation Authorization (ODA) Approvals

APB stated that Boeing does not have a delegation to approve repairs in areas affected by the scimitar blended winglet configuration of STC ST01518SE. APB also commented that approval by The Boeing Company ODA, as specified in paragraph (i)(3) of the proposed AD, may not be given for an alternative method of compliance (AMOC) for alternative inspections and corrective actions in those areas, but such approval must be obtained as specified in paragraph (i)(1) of the proposed AD.

The FAA acknowledges and concurs with APB's assertions. However, no change to this proposed AD is necessary. Paragraph (h)(2) of this proposed AD states that AMOC approval be obtained using a method approved in accordance with the procedures specified in “paragraph (i)” of this proposed AD, and does not limit approvals to the provisions of paragraph (i)(1) or (3) of this proposed AD. Therefore, AMOC approval in accordance with paragraph (i)(1) or (3) of this proposed AD would be provided based on whether the actions needing an AMOC apply to the APB design or the Boeing design.

Request for Changing an Exception

APB requested changing the wording in paragraph (h)(3) of the proposed AD to clarify that it applies to airplanes with winglet structural provisions (original equipment manufacturer (OEM) wingtips installed) or APB winglets installed in accordance with STC ST01518SE. APB stated the compliance time exception in paragraph (h)(3) of the proposed AD are identical to the exceptions proposed by APB in a service bulletin submitted to the FAA for approval. APB noted that if the compliance time exceptions are adopted as proposed, paragraph (h)(3) of the proposed AD would eliminate the need for APB to publish supplemental service information.

The FAA agrees the compliance times should be the same for all airplanes that have been modified using STC ST01518SE. However, there is no FAA-approved APB service bulletin to address the unsafe condition, nor does the FAA have adequate justification to allow the repetitive inspection interval specified in the NPRM. Therefore, the FAA has revised paragraph (h)(3) of this proposed AD to specify that, for all airplanes modified using STC ST01518SE the compliance times must be divided by a factor of two. Under the provisions of paragraph (i) of this proposed AD, the FAA will consider requests for approval of alternative actions and compliance times if sufficient data are submitted to substantiate that the change would provide an acceptable level of safety.

Request To Change Requirements for Certain Airplanes

FedEx requested the proposed AD be revised to allow using alternative compliance methods and times for its airplanes. FedEx noted that its 757 fleet has been modified using VT MAE STC ST03562AT, which adds a main deck cargo door to the aircraft. FedEx requested modifications to the requirements for Groups 1, 2, and 3 airplanes, allowing it to use alternative figures, repetitive intervals, and compliance methods.

The FAA disagrees with the request because the commenter did not provide adequate substantiation that using the proposed alternative compliance methods and times adequately addresses the identified unsafe condition. However, under the provisions of paragraph (i) of this proposed AD, the FAA will consider requests for approval of alternative compliance methods or times if sufficient data are submitted to substantiate that the new compliance methods and times would provide an acceptable level of safety. The FAA has not changed this proposed AD in this regard.

Request for Change to Related Service Information Under 1 CFR Part 51

Boeing requested the FAA revise a sentence in the Related Service Information under 1 CFR part 51 to read as follows: “. . . for repetitive high frequency eddy current (HFEC) and low frequency eddy current (LFEC) inspections for cracking of the upper frames and splice doublers at the frame splices.” Boeing noted that, for airplanes in Group 4, 5, and 6, it is a requirement to inspect both the frame and splice doublers. Boeing stated the proposed change will clarify that inspection of the splice doublers is required for some airplanes.

The FAA agrees with the commenter for the reasons provided and has revised the proposed AD accordingly.

Request To Clarify Repairs Requiring Additional Action

UPS requested that the FAA clarify the proposed AD regarding the repairs found during the required general visual inspection (GVI) or maintenance records review. UPS stated Boeing Alert Requirements Bulletin 757-53A0115 RB, dated January 25, 2022, does not fully define “any repair.” UPS stated that Boeing 757-200PF Structural Repair Manual (SRM) 53-00-01-1A-1 allows for smooth dents, edge and surface blends, and plugging of removed damage areas in the frame web within the affected inspection area. UPS added that the repairs within the SRM allowable limits have no supplemental inspections, so such repairs do not appreciably affect damage tolerance of the fuselage frames. UPS stated that it believes the intent of the GVI or maintenance records review is to identify and report existing reinforcing repairs that may affect damage tolerance of the frame. UPS therefore requested the addition of paragraph (h)(4) of the proposed AD, stating “Where Boeing Alert Requirements Bulletin 757-53A0115 RB, dated January 25, 2022, uses the phrase “any repair,” this AD requires using “any reinforcing repair.”

The FAA disagrees with the commenter's request. The FAA has no way of knowing the type or extent of repairs that might be on a given airplane or how those repairs would impact the actions required by this AD. Therefore, any existing repair, including any non-reinforced repair, needs to be evaluated for any potential effect on the inspection requirements. The FAA has not changed this proposed AD in this regard.

FAA's Determination

The FAA is proposing this AD after determining the unsafe condition described previously is likely to exist or develop in other products of the same type design. Certain changes described above expand the scope of the NPRM. As a result, it is necessary to reopen the comment period to provide additional opportunity for the public to comment on this SNPRM.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Boeing Alert Requirements Bulletin 757-53A0115 RB, dated January 25, 2022. This service information specifies procedures for a GVI or records review between stringers S-13 and S-14 in Sections 43 and 46 for existing repairs. This service information also describes procedures, depending on the configuration, for repetitive HFEC and LFEC inspections for cracking of the upper frames and splice doublers at the frame splices between stringers S-13 and S-14, left- and right-hand sides, in Sections 43 and 46; 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 ADDRESSES .

Proposed AD Requirements in This SNPRM

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 by searching for and locating Docket No. FAA-2023-1053.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would affect 456 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
GVI	2 work-hours × $85 per hour = $170 per inspection cycle	$0	$170 per inspection cycle	$77,520 per inspection cycle.
Repetitive Inspections	Up to 267 work-hour × $85 per hour = Up to $22,695 per inspection cycle	0	Up to $22,695 per inspection cycle	Up to $10,348,920 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.

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 adding the following new airworthiness directive:

The Boeing Company: Docket No. FAA-2023-1053; Project Identifier AD-2023-00164-T.

(a) Comments Due Date

The FAA must receive comments on this airworthiness directive (AD) by June 6, 2024.

(b) Affected ADs

None.

(c) Applicability

This AD applies to The Boeing Company Model 757-200, -200CB, and -200PF series airplanes, certificated in any category, as identified in Boeing Alert Requirements Bulletin 757-53A0115 RB, dated January 25, 2022.

(d) Subject

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

(e) Unsafe Condition

This AD was prompted by a crack growth analysis, which indicated that current inspections are not adequate to detect cracks in the Sections 43 and 46 upper frame at the frame splice between stringers S-13 and S-14 before a single frame fails. The FAA is issuing this AD to address cracking at the upper frames common to the splice at stringers S-13 to S-14, which could interact with fuselage skin cracking at the stringer S-14 lap splice. The unsafe condition, if not addressed, could result in the inability of a principal structural element to sustain limit loads, 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 757-53A0115 RB, dated January 25, 2022, do all applicable actions identified in, and in accordance with, the Accomplishment Instructions of Boeing Alert Requirements Bulletin 757-53A0115 RB, dated January 25, 2022.

Note 1 to paragraph (g): Guidance for accomplishing the actions required by this AD can be found in Boeing Alert Service Bulletin 757-53A0115, dated January 25, 2022, which is referred to in Boeing Alert Requirements Bulletin 757-53A0115 RB, dated January 25, 2022.

(h) Exceptions to Service Information Specifications

(1) Where the Compliance Time columns of the tables in the “Compliance” paragraph of Boeing Alert Requirements Bulletin 757-53A0115 RB, dated January 25, 2022, use the phrase “the original issue date of Requirements Bulletin 757-53A0115 RB,” this AD requires using the effective date of this AD.

(2) Where Boeing Alert Requirements Bulletin 757-53A0115 RB, dated January 25, 2022, specifies contacting Boeing for repair instructions or for alternative inspections: This AD requires doing the repair and doing the alternative inspections and applicable on-condition actions using a method approved in accordance with the procedures specified in paragraph (i) of this AD.

(3) For airplanes on which winglet structural provisions (original equipment manufacturer (OEM) wingtips) or Aviation Partners Boeing (APB) winglets have been installed in accordance with APB Supplemental Type Certificate (STC) ST01518SE: This AD requires dividing the applicable compliance times and repeat intervals specified in the “Compliance” paragraph of Boeing Requirements Bulletin 757-53A0115 RB, dated January 25, 2022, by a factor of two.

(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: [e-mail].

(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, 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 Wayne Ha, Aviation Safety Engineer, Continued Operational Safety Branch, FAA, 2200 South 216th Street, Des Moines, WA 98198; phone: [phone]; email: [e-mail].

(2) Service information identified in this AD that is not incorporated by reference is available at the address specified in paragraph (k)(3) 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 the AD specifies otherwise.

(i) Boeing Alert Requirements Bulletin 757-53A0115 RB, dated January 25, 2022.

(ii) [Reserved]

(3) For Boeing service information, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; telephone [phone]; 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 [e-mail].

Issued on April 16, 2024.

Victor Wicklund,

Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.