2020-06508. Airworthiness Directives; The Boeing Company Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for all The Boeing Company Model 757-200, -200PF, -200CB, and -300 series airplanes. This AD was prompted by a report that during a maintenance check an operator discovered cracking of the aft cargo compartment frames in the station 1460 frame web and inner chord between certain stringers. This AD requires an inspection of the fuselage frames for any existing repair, repetitive surface high frequency eddy current (HFEC) inspections of the fuselage frames with a cargo liner support channel for any cracking, and applicable on-condition actions. The FAA is issuing this AD to address the unsafe condition on these products.

DATES:

This AD is effective May 4, 2020.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of May 4, 2020.

ADDRESSES:

For service information identified in this final rule, contact Boeing Commercial Airplanes, Attention: Contractual & Data Services (C&DS), 2600 Westminster Blvd., MC 110-SK57, Seal Beach, CA 90740-5600; telephone [phone]; internet https://www.myboeingfleet.com. You may view this service information at the FAA, Transport Standards 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-2019-0438.

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-2019-0438; 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 final rule, the regulatory evaluation, any comments received, and other information. The address for Docket Operations is U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT:

Peter Jarzomb, Aerospace Engineer, Airframe Section, FAA, Los Angeles ACO Branch, 3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: [phone]; fax: [phone]; email: [e-mail].

SUPPLEMENTARY INFORMATION:

Discussion

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to all The Boeing Company Model 757 airplanes. The NPRM published in the Federal Register on June 28, 2019 (84 FR 30958). The NPRM was prompted by a report that during a maintenance check an operator discovered cracking of the aft cargo compartment frames in the station 1460 frame web and inner chord between stringers S-26 and S-27 near an existing repair. The NPRM proposed to require an inspection of the fuselage frames for any existing repair, repetitive surface HFEC inspections of the fuselage frames with a cargo liner support channel for any cracking, and applicable on-condition actions.

The FAA issued a supplemental notice of proposed rulemaking (SNPRM) to amend 14 CFR part 39 by adding an AD that would apply to all The Boeing Company Model 757 airplanes. The SNPRM published in the Federal Register on December 2, 2019 (84 FR 65931). The FAA issued the SNPRM to reduce the compliance time for certain airplane configurations.

The FAA is issuing this AD to address cracking at the frame web and inner chord; such cracks could propagate until they cause a severed frame, which could result in additional undetected cracking in adjacent fuselage frames, and could ultimately result in reduced structural integrity of the aft cargo frames and consequent rapid decompression of the airplane.

Comments

The FAA gave the public the opportunity to participate in developing this final rule. The following presents the comments received on the SNPRM and the FAA's response to each comment.

Support for the SNPRM

Boeing and United Airlines concurred with the SNPRM. FedEx stated they had no objection to the SNPRM.

Request To Utilize Actions for a Certain Airplane Group and a Compliance Time for Another Airplane Group

VT Mobile Aerospace Engineering Inc. (VT MAE Inc.) requested to utilize inspections and methods for Group 7 airplanes, and utilize the compliance times for Groups 3 and 5 airplanes, which would reduce the repetitive inspection interval from 6,000 flight cycles to 4,000 flight cycles. VT MAE Inc. stated that its Model 757-200 airplanes were converted to freighter configuration per VT MAE Inc. supplemental type certificate (STC) ST04242AT (15 pallet configuration) and VT MAE Inc. STC ST03952AT (combi configuration/14 pallet configuration), and are no longer configured as a passenger airplanes. VT MAE Inc. also stated that Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, shows that its converted Model 757-200 freighter fleet falls under Group 7 airplanes. VT MAE Inc. provided no justification for using compliance times for different airplane groups.

The FAA agrees to provide additional clarification. The FAA issued the SNPRM to add an airplane configuration to the NPRM that addressed FedEx's fleet of 119 airplanes (approximately 22% of the affected U.S. fleet) that were converted from a passenger configuration to a freighter configuration using VT MAE Inc. STC ST03562AT. It was determined that these airplanes are subjected to the same fatigue loads as Groups 3 and 5 airplanes, as specified in Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019. Therefore, paragraph (g)(2) of this AD was added in the SNPRM to address the required actions and compliance times for this added airplane configuration.

The FAA agrees with VT MAE Inc.'s comments that airplanes modified using VT MAE Inc. STC ST04242AT and VT MAE Inc. STC ST03952AT are no longer configured as passenger airplanes. However, the FAA disagrees with the request to include additional exceptions in this AD that are specific to certain airplanes converted by VT MAE Inc. There are many different airplane configurations across multiple operators, and ADs cannot accommodate all possible configurations.

The FAA has already delayed this AD to address one configuration. To reduce the compliance time of the proposed AD for airplanes modified using VT MAE Inc. STCs ST04242AT and ST003952AT would necessitate (under the provisions of the Administrative Procedure Act) reissuing the notice, reopening the period for public comment, considering additional comments subsequently received, and eventually issuing a final rule. That procedure could add unwarranted time to the rulemaking process. To delay this AD again would be inappropriate, since the FAA has determined that an unsafe condition exists and that inspections must be conducted to ensure continued safety. However, if additional data are presented that would justify a shorter compliance time for these airplanes, the FAA may consider further rulemaking on this issue. Under the provisions of paragraph (i) of this 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. The FAA has not changed this AD in this regard.

Request To Revise the Language in Note (a) of the Service Information

DAL requested that the language in Note (a) of paragraph “3. Compliance,” of Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, be revised from “meets the following criteria” to “meets one of the following criteria,” and to also add “757-200 SRM [Structural Repair Manual] 53-00-07 Repair 5” to the criteria. DAL stated that it interprets the note to mean either criterion 1 or criterion 2 provides relief from performing the subject inspections and that the statement only takes into consideration that a repair may be approved using FAA Form 8100-9. DAL commented that “757-200 SRM 53-00-07 Repair 5” is also an FAA-approved repair for aft cargo compartment lower frames. DAL commented that the Boeing 757 SRM and any repair approved by The Boeing Organization Designation Authorization (ODA) using FAA Form 8100-9 are both FAA-approved and have damage tolerance analyses.

The FAA disagrees with the comment. Note (a) in Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, is intended to address repairs that were designed as corrective actions to the unsafe condition addressed in the service information and this AD, are Boeing ODA-approved, and include a follow-on inspection program, but were installed before this AD becomes effective. For this reason, the FAA allows FAA Form 8100-9 for approved repairs that meet both criteria (1) and (2) specified in Note (a) of Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, to be exempted from the inspections in those repaired areas, but do not allow just any FAA-approved repair to be exempted from these required inspections. However, under the provisions of paragraph (i) of this AD, the FAA will consider requests for approval of certain repairs in this area that affect compliance with this AD if sufficient data are submitted to substantiate that the change would provide an acceptable level of safety. The FAA has not changed this AD in this regard.

Request To Revise Certain Wording

DAL pointed out that Sheet 3 of 3 of Figure 21 of Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, contains an error in the inspection task description. DAL stated that the inspection task description and general visual inspection for station 1260 nomenclature should be “FRAME” instead of “FRAME WEB.” DAL also stated that the procedure is to do a general visual inspection for any existing repairs in the area prior to accomplishing a detailed inspection and HFEC inspection. DAL commented that this is also consistent with the other general visual inspection nomenclature of adjacent frames to a frame found with a severed inner chord on Group 12 airplanes.

From these statements, the FAA infers that DAL was requesting that the SNPRM be revised to correct the error in Figure 21 (Sheet 3 of 3) of Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019. The FAA disagrees with the commenter's request. While the FAA agrees that the name of the part specified in Figure 21 (Sheet 3 of 3) of Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, is incorrect, it will not affect the operator's ability to accomplish the inspection in Figure 21 (Sheet 3 of 3) of Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, as the location where the inspection is to be performed is clearly identified in the figure. The FAA has not changed this AD in this regard.

Request To Define “Unrepaired Locations”

Delta Airlines (DAL) requested that the FAA define “unrepaired locations” in the SNPRM to eliminate misinterpretations. DAL stated that it has interpreted the definition of “unrepaired locations” to mean the areas of each frame that do not have a repair, which interferes with accomplishment of the HFEC inspection. DAL commented that this interpretation is based on the possibility that airplanes in a cargo liner attachment channel configuration with two fasteners may have one fastener location with an interfering repair and one fastener location without an interfering repair. DAL also stated that it possible to interpret “unrepaired locations” to mean only body stations with fuselage frames free of existing repairs.

The FAA disagrees with the commenter's request. The service information defines the locations that are to be inspected for repairs and cracks. Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, specifies operators to do a general visual inspection of the fuselage frames with a cargo liner support channel for any existing repair and provides figures that define the areas where these inspections for repairs are to be performed. The on-condition actions in Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, then specify that if a repair in the inspection area is found to contact Boeing for alternative inspections and then to do those inspections and any corrective actions, as applicable. Paragraph (h) of this AD requires operators to do the repair, or alternative inspections and applicable on-condition actions using a method approved in accordance with the procedures specified in paragraph (i) of this AD. In addition, Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, specifies that operators perform the inspections for cracks at the locations that did not have repairs and provides figures that clearly define those inspection areas. The FAA has not changed this AD in this regard.

Conclusion

The FAA reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this final rule as proposed, except for minor editorial changes. The FAA has determined that these minor changes:

• Are consistent with the intent that was proposed in the SNPRM for addressing the unsafe condition; and
• Do not add any additional burden upon the public than was already proposed in the SNPRM.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019. This service information describes procedures for a general visual inspection of the fuselage frames with a cargo liner support channel for any existing repair, repetitive surface HFEC inspections of the fuselage frames with a cargo liner support channel for any cracking, and applicable on-condition actions. On-condition actions include a general visual inspection of the fuselage frames adjacent to a frame with a severed inner chord for any existing repair, a detailed inspection and a surface HFEC inspection of the fuselage frames adjacent to a frame with a severed inner chord for any cracking, and 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.

Costs of Compliance

The FAA estimates that this AD affects 544 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD:

Estimated Costs for Required Actions

Action	Labor cost	Parts cost	Cost per product	Cost on U.S. operators
General visual inspection	37 work-hours × $85 per hour = $3,145	$0	$3,145	$1,710,880.
Repetitive surface HFEC inspections	Up to 37 work-hours × $85 per hour = Up to $3,145 per inspection cycle	0	Up to $3,145 per inspection cycle	Up to $1,710,880 per inspection cycle.

The FAA estimates the following costs to do any necessary on-condition inspections that would be required. The FAA has no way of determining the number of aircraft that might need these on-condition inspections:

Estimated Costs of On-Condition Actions

Labor cost	Parts cost	Cost per product
Up to 20 work-hour × $85 per hour = Up to $1,700 per inspection cycle	$0	Up to $1,700 per inspection cycle.

The FAA has received no definitive data that would enable the agency to provide cost estimates for the on-condition repair specified in this 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

This AD will not have federalism implications under Executive Order 13132. This AD will 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 that this AD:

(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

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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 (AD):

2020-05-25 The Boeing Company: Amendment 39-19875; Docket No. FAA-2019-0438; Product Identifier 2019-NM-033-AD.

(a) Effective Date

This AD is effective May 4, 2020.

(b) Affected ADs

None.

(c) Applicability

(1) This AD applies to all The Boeing Company Model 757-200, -200PF, -200CB, and -300 series airplanes, certificated in any category.

(2) Installation of Supplemental Type Certificate (STC) ST01518SE does not affect the ability to accomplish the actions required by this AD. Therefore, for airplanes on which STC ST01518SE is installed, a “change in product” alternative method of compliance (AMOC) approval request is not necessary to comply with the requirements of 14 CFR 39.17.

(d) Subject

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

(e) Unsafe Condition

This AD was prompted by a report that during a maintenance check an operator discovered cracking of the aft cargo compartment frames in the station 1460 frame web and inner chord between certain stringers. The FAA is issuing this AD to address cracking at the frame web and inner chord; such cracks could propagate until they cause a severed frame, which could result in additional undetected cracking in adjacent fuselage frames, and could ultimately result in reduced structural integrity of the aft cargo frames and consequent rapid decompression of the airplane.

(f) Compliance

Comply with this AD within the compliance times specified, unless already done.

(g) Required Actions

(1) Except as specified by paragraphs (g)(2) and (h) of this AD: At the applicable times specified in the “Compliance” paragraph of Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, do all applicable actions identified in, and in accordance with, the Accomplishment Instructions of Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019.

(2) For airplanes that have been converted from a passenger to freighter configuration using VT Mobile Aerospace Engineering Inc. (VT MAE Inc.) STC ST03562AT: Except as specified by paragraph (h) of this AD, at the times specified for Groups 3 and 5 airplanes, as applicable, in the “Compliance” paragraph of Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, do all applicable actions for Groups 2, 7, and 10 airplanes as identified in, and in accordance with the Accomplishment Instructions of Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019.

Note 1 to paragraph (g):

Guidance for accomplishing the actions required by this AD can be found in Boeing Alert Service Bulletin 757-53A0113, dated February 22, 2019, which is referred to in Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019.

(h) Exceptions To Service Information Specifications

(1) Where Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, uses the phrase “the original issue date of Requirements Bulletin 757-53A0113 RB,” this AD requires using “the effective date of this AD,” except where Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, uses the phrase “the original issue date of Requirements Bulletin 757-53A0113 RB” in a note or flag note.

(2) Where Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019, specifies contacting Boeing for repair instructions or for alternative inspections: This AD requires doing the repair, or doing the alternative inspections and applicable on-condition actions 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, Los Angeles 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: [e-mail].

(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, Los Angeles 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 Peter Jarzomb, Aerospace Engineer, Airframe Section, FAA, Los Angeles ACO Branch, 3960 Paramount Boulevard, Lakewood, CA 90712-4137; phone: [phone]; fax: [phone]; email: [e-mail].

(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 the AD specifies otherwise.

(i) Boeing Alert Requirements Bulletin 757-53A0113 RB, dated February 22, 2019.

(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 [phone]; internet https://www.myboeingfleet.com.

(4) You may view this service information at the FAA, Transport Standards 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 service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, email [e-mail], or go to: https://www.archives.gov/​federal-register/​cfr/​ibr-locations.html.

Issued on March 10, 2020.

Gaetano A. Sciortino,

Deputy Director for Strategic Initiatives, Compliance & Airworthiness Division, Aircraft Certification Service.