2012-13055. Airworthiness Directives; The Boeing Company Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Supplemental notice of proposed rulemaking (NPRM); reopening of comment period.

SUMMARY:

We are revising an earlier proposed airworthiness directive (AD) for all The Boeing Company Model 757 airplanes. That NPRM proposed to require a detailed inspection of the inboard and outboard main slat track downstop assemblies and a torque application to the main track downstop assembly nuts of slat numbers 1 through 10, excluding the outboard track of slats 1 and 10; a detailed inspection of all slat track housings for foreign object debris (FOD) and visible damage; and corrective actions if necessary. That NPRM was prompted by reports of fuel leaking from the front spar of the wing through the slat track housing. This action revises that NPRM by adding inspection results reporting. We are proposing this supplemental NPRM to detect and correct incorrectly installed main slat track downstop assemblies, which, when the slat is retracted, could cause a puncture in the slat track housing and lead to a fuel leak and potential fire. Since these actions impose an additional burden over that proposed in the NPRM, we are reopening the comment period to allow the public the chance to comment on these proposed changes.

DATES:

We must receive comments on this supplemental NPRM by July 16, 2012.

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 http://www.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: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; phone: [phone], extension 1; fax: [phone]; email: [e-mail]; Internet: https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov;​; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Office (phone: [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Nancy Marsh, Aerospace Engineer, Airframe Branch, ANM-120S, Seattle Aircraft Certification Office (ACO), FAA, 1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: [phone]; fax: [phone]; email: [e-mail].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2010-0547; Directorate Identifier 2009-NM-234-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD because of those comments.

We will post all comments we receive, without change, to http://www.regulations.gov,, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD.

Discussion

We issued an NPRM to amend 14 CFR part 39 to include an AD that would apply to all The Boeing Company Model 757 airplanes. That NPRM published in the Federal Register on June 3, 2010 (75 FR 31327). That NPRM proposed to require a detailed inspection of the inboard and outboard main slat track downstop assemblies and a torque application to the main track downstop assembly nuts of slat numbers 1 through 10, excluding the outboard track of slats 1 and 10; a detailed inspection of all slat track housings for FOD and visible damage; and corrective actions if necessary.

Actions Since Previous NPRM (75 FR 31327, June 3, 2010) Was Issued

Since we issued the previous NPRM (75 FR 31327, June 3, 2010), we have determined that the service information referenced in the NPRM, Boeing Special Attention Service Bulletin 757-57-0068, dated September 15, 2009, contains inspections for certain part numbers that do not exist and errors in certain figures.

Relevant Service Information

We have reviewed Boeing Special Attention Bulletin 757-57-0068, Revision 1, dated July 19, 2011. This service information clarifies certain part numbers, downstop assembly components, and torquing requirements for downstop fasteners; and adds an option to replace the slat can instead of repairing it. This service information also corrects the part numbers to be inspected and corrects the errors found in Boeing Special Attention Service Bulletin 757-57-0068, dated September 15, 2009.

FAA's Determination

We are proposing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.

Comments

We gave the public the opportunity to comment on the previous NPRM (75 FR 31327, June 3, 2010). The following presents the comments received on the NPRM and the FAA's response to each comment.

Agreement With the Intent of the NPRM (75 FR 31327, June 3, 2010)

American Airlines (American) stated that, in general, it agrees with the intent of the previous NPRM (75 FR 31327, June 3, 2010).

Concurrence With the Proposed Inspection and Follow-On Actions

Continental Airlines (Continental) stated that it concurs with the proposed inspection and follow-on actions.

Requests To Clarify Reporting Results

Boeing, Delta Air Lines (Delta), and FedEx requested that we clarify if reporting the inspection results is required. Boeing stated that the reporting request is not shown in paragraph (h) of the NPRM (75 FR 31327, June 3, 2010). Delta stated that reporting for this subject does not add safety to the rule.

Boeing Special Attention Service Bulletin 757-57-0068, Revision 1, dated July 19, 2011, specifies reporting and includes an appendix for reporting the inspection results. The extent of FOD, visible damage, and missing parts is not known. Inspection reports will help determine the extent of the safety issue in the affected fleet. Based on the results of these reports, we will determine if further rulemaking is warranted. Therefore, we have added new paragraph (i) in this supplemental NPRM (SNPRM) to require operators to report the inspection results.

Request To Make the Inspection Repetitive

American stated that a repetitive inspection program and/or airplane maintenance manual (AMM) revision may be necessary to prevent the unsafe condition. American justified its request by stating that the hardware may be changed using the AMM after the one-time inspection, and that maintenance could result in a loose torque to the downstop assembly nut.

We disagree with revising this SNPRM to incorporate additional inspections or AMM revisions at this time. The SNPRM proposes a one-time inspection, and reporting. If we receive reports of discrepancies in the downstop hardware or of FOD in the slat cans, we may consider additional rulemaking to address the unsafe condition. If operators are doing maintenance on the slat track downstop hardware using the AMMs, they should follow the instructions in the AMM and correctly torque the nut. The torque values in the AMM are the same as those in Boeing Special Attention Service Bulletin 757-57-0068, Revision 1, dated July 19, 2011. Boeing is not aware of any errors in the AMMs. Boeing has also added cautionary notes to the pertinent sections of the AMM advising the operators to correctly torque the nut, and to ensure that no FOD has dropped in to the slat can. We have not changed the SNPRM in this regard.

Request To Delay Issuing the Rule

FedEx expressed concern over the availability of spare parts. FedEx stated that some replacement parts are not currently available from Boeing or are in very limited supply. We infer that FedEx requested we delay issuing the rule until additional supplies of spare parts are available.

We disagree. The objective of this SNPRM is to detect and correct fuel leaks in the slat cans and prevent a potential fire. To delay this action would be inappropriate, since we have determined that an unsafe condition exists and that inspections must be conducted to ensure continued safety. Additionally, based on reports received to date, Boeing does not anticipate the need for significant numbers of part replacements. We have not changed the SNPRM in this regard.

Request To Correct Service Information

Continental and Delta requested resolution of the errors in the service information.

Continental requested that the illustrated parts catalog be permitted for use in determining correct part numbers and alternative part numbers.

Delta noted that the torque values in the service information may be incorrect and that the illustrations of proper assembly are incorrect. Delta also requested that we revise the NPRM (75 FR 31327, June 3, 2010) to specify that the actions be accomplished using the better illustrations available in the AMM.

We agree with the commenters that corrections to Boeing Special Attention Service Bulletin 757-57-0068, dated September 15, 2009, are needed. We have revised the SNPRM to require Boeing Special Attention Service Bulletin 757-57-0068, Revision 1, dated July 19, 2011, which corrects the errors specified by the commenters. We have also added new paragraph (j) to this SNPRM to provide credit for actions accomplished before the effective date of the AD in accordance with Boeing Special Attention Bulletin 757-57-0068, dated September 15, 2009, provided the inspection results were reported as specified in that service bulletin.

Request To Allow Replacement of Parts

American requested that the NPRM (75 FR 31327, June 3, 2010) be revised to allow replacing damaged parts with new parts as an alternative to repairing damaged parts. American justified its request by stating that it may be easier to simply replace a damaged housing than to remove the damage.

We partially agree. We agree with the commenter that this change is warranted because a replacement part is an acceptable repair. We disagree with changing the SNPRM, because Boeing has revised Boeing Special Attention Service Bulletin 757-57-0068, to allow either part replacement or repair. As stated previously, we have changed the SNPRM to refer to Boeing Special Attention Service Bulletin 757-57-0068, Revision 1, dated July 19, 2011.

Request To Account for Errors in Figure 11 of the Service Information

American and Delta requested a provision in the NPRM (75 FR 31327, June 3, 2010) to account for errors in Figure 11 of Boeing Special Attention Bulletin 757-57-0068, dated September 15, 2009. The commenters justified the request by stating that the dimensioning of the allowable blendout in Figure 11 of Boeing Special Attention Bulletin 757-57-0068, dated September 15, 2009, is unclear.

We partially agree. We agree with the commenters that the figure in Boeing Special Attention Bulletin 757-57-0068, dated September 15, 2009, is unclear. We disagree with revising this SNPRM, because Boeing has provided corrected service instructions in Boeing Special Attention Service Bulletin 757-57-0068, Revision 1, dated July 19, 2011. As stated previously, we have changed the SNPRM to refer to this revision of the service information.

Clarification of Inspection Requirements

We have revised paragraph (g) of the SNPRM to clarify that the purpose of the detailed inspection of the inboard and outboard main track downstop assemblies of slat numbers 1 through 10, excluding the outboard main track downstop assemblies of slat numbers 1 and 10, is to determine the assembly order and to detect missing or damaged parts.

FAA's Determination

We are proposing this SNPRM because we evaluated all the relevant information and determined 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 original NPRM (75 FR 31327, June 3, 2010). As a result, we have determined that it is necessary to reopen the comment period to provide additional opportunity for the public to comment on this SNPRM.

Proposed Requirements of the SNPRM

This SNPRM would require accomplishing the actions specified in the service information described previously, except as discussed under “Differences Between the SNPRM and the Service Information.” This SNPRM also requires sending the inspection results to Boeing.

Differences Between the SNPRM and the Service Information

Boeing Special Attention Bulletin 757-57-0068, Revision 1, dated July 19, 2011, specifies to contact the manufacturer for instructions on how to repair certain conditions, but this SNPRM would require repairing those conditions in one of the following ways:

• Using a method that we approve; or
• Using data that meet the certification basis of the airplane, and that have been approved by the Boeing Commercial Airplanes Organization Designation Authorization (ODA) that we have authorized to make those findings.

Costs of Compliance

We estimate that this proposed AD affects 645 airplanes of U.S. registry.

We estimate 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	20 work-hours × $85 per hour = $1,700	$0	$1,700	$1,096,500

We have received no definitive data that would enable us to provide 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.

We are 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

We 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) Is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979),

(3) Will not affect intrastate aviation in Alaska, and

(4) 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

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 (AD):

The Boeing Company: Docket No. FAA-2010-0547; Directorate Identifier 2009-NM-234-AD.

(a) Comments Due Date

We must receive comments by July 16, 2012.

(b) Affected ADs

None.

(c) Applicability

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

(d) Subject

Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 57, Wings.

(e) Unsafe Condition

This AD was prompted by reports of fuel leaking from the front spar of the wing through the slat track housing. We are issuing this AD to detect and correct incorrectly installed main track downstop assemblies, which, when the slat is retracted, could cause a puncture in the slat track housing and lead to a fuel leak and potential fire.

(f) Compliance

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

(g) Inspection and Torque Application

Except as required by paragraph (h)(1) of this AD, at the applicable time specified in paragraph 1.E., “Compliance,” of Boeing Special Attention Service Bulletin 757-57-0068, Revision 1, dated July 19, 2011: Do the actions in paragraphs (g)(1) and (g)(2) of this AD.

(1) Perform a detailed inspection of the inboard and outboard main track downstop assemblies of slat numbers 1 through 10, excluding the outboard main track downstop assemblies of slat numbers 1 and 10, for correct assembly order and missing or damaged parts; perform a detailed inspection of all slat track housings for foreign object debris, visible damage, and missing parts; and do all applicable corrective actions; in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-57-0068, Revision 1, dated July 19, 2011, except as required by paragraph (h)(2) of this AD. Do all applicable corrective actions before further flight.

(2) Apply torque to the main track down stop assembly nuts to make sure they have been correctly installed, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-57-0068, Revision 1, dated July 19, 2011.

(h) Exceptions to the Service Bulletin

(1) Where Boeing Special Attention Service Bulletin 757-57-0068, Revision 1, dated July 19, 2011, specifies a compliance time “after the date on this service bulletin,” this AD requires compliance at the specified time after the effective date of this AD.

(2) Where Boeing Special Attention Service Bulletin 757-57-0068, Revision 1, dated July 19, 2011, specifies to contact Boeing for appropriate action: Before further flight, repair the damage using a method approved in accordance with the procedures specified in paragraph (l)(1) of this AD.

(i) Reporting Requirement

If any of the conditions specified in paragraph B.3., “Part 3—Appendix A: Inspection Results Report,” of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 757-57-0068, Revision 1, dated July 19, 2011, are found during the inspection required by paragraph (g) of this AD, submit a report of the inspection findings at the applicable time specified in paragraph (i)(1) or (i)(2) of this AD, as specified in Appendix A of Boeing Special Attention Service Bulletin 757-57-0068, Revision 1, dated July 19, 2011, to Boeing through the Boeing Communication System (BCS). The report must include a description of any discrepancies found, the airplane serial number, and the number of landings and flight hours on the airplane.

(1) If the inspection was done on or after the effective date of this AD: Submit the report within 30 days after the inspection.

(2) If the inspection was done before the effective date of this AD: Submit the report within 30 days after the effective date of this AD.

(j) Credit for Previous Actions

This paragraph provides credit for inspections and corrective actions required by paragraph (g) of this AD, if the inspections and corrective actions were performed before the effective date of this AD using Boeing Special Attention Bulletin 757-57-0068, dated September 15, 2009, provided the inspection results were reported as specified in Boeing Special Attention Bulletin 757-57-0068, dated September 15, 2009.

(k) Paperwork Reduction Act Burden Statement

A federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to a penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a current valid OMB Control Number. The OMB Control Number for this information collection is 2120-0056. Public reporting for this collection of information is estimated to be approximately 5 minutes per response, including the time for reviewing instructions, completing, and reviewing the collection of information. All responses to this collection of information are mandatory. Comments concerning the accuracy of this burden and suggestions for reducing the burden should be directed to the FAA at: 800 Independence Ave. SW., Washington, DC 20591, Attn: Information Collection Clearance Officer, AES-200.

(l) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Seattle Certification Office (ACO), 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 ACO, send it to the attention of the person identified in the Related Information section 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 required by this AD if it is approved by the Boeing Commercial Airplanes Organization Designation Authorization (ODA) that has been authorized by the Manager, Seattle ACO to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane and the approval must specifically refer to this AD.

(m) Related Information

(1) For more information about this AD, contact Nancy Marsh, Aerospace Engineer, Airframe Branch, ANM-120S, Seattle Aircraft Certification Office (ACO), FAA, 1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: [phone]; fax: [phone]; email: [e-mail].

(2) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; phone: [phone], extension 1; fax: [phone]; email: [e-mail]; Internet: https://www.myboeingfleet.com. You may review copies of the referenced service information at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington. For information on the availability of this material at the FAA, call 425-227-1221.

Issued in Renton, Washington, on May 18, 2012.

Michael Kaszycki,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.