2013-08342. Airworthiness Directives; The Boeing Company Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

We propose to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 767-200, -300, -300F, and -400ER series airplanes. This proposed AD was prompted by reports of cracked and corroded nuts on an outboard flap support rib. This proposed AD would require, for certain airplanes, repetitive inspections of the cap seal for damaged sealant on nuts common to certain outboard flap support ribs, related investigative and corrective actions if necessary, and replacement of all fasteners in the support ribs, which terminates the repetitive inspections. For certain other airplanes, this proposed AD would require repetitive inspections of the cap seal for damaged sealant on nuts common to certain outboard flap support ribs, related investigative and corrective actions if necessary, and if necessary, a detailed inspection to determine the nut type installed in the outboard flap support rib and corrective actions; for these airplanes, this proposed AD provides optional replacement of all fasteners in the support ribs, which would terminate the repetitive inspections. We are proposing this AD to detect and correct cracked and corroded nuts and bolts and the installation of incorrect nuts on certain outboard flap support ribs, which could lead to additional nut and bolt damage in the joint, and result in loss of an outboard flap, and adversely affect continued safe flight and landing of the airplane.

DATES:

We must receive comments on this proposed AD by May 28, 2013.

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: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For Boeing service information identified in this proposed AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone [phone], extension 1; fax [phone]; 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:

Berhane Alazar, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 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 proposal. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2013-0301; Directorate Identifier 2013-NM-025-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 received reports that two cracked and corroded nuts were found on support rib number 2 of an outboard flap. It was determined that incorrect nuts were installed on support rib numbers 2 and 7. The correct nuts for this installation have part number (P/N) BACN10HR12 and a torque of 3,300 to 4,300 inch-pounds (in-lbs). The installed incorrect nuts have P/N NAS1804-12 and a torque of 2,400 to 3,500 in-lbs. The installed P/N NAS1804-12 nuts might have been over-torqued. Over-torqued nuts are at risk of fracture. Fractured nuts could create a breach in the cap seal and allow moisture to contact the nuts, resulting in corrosion. Nut fractures could lead to additional nut or bolt fractures within that support rib, and these additional fractures could cause the joint to be compromised. We are proposing this AD to detect and correct cracked and corroded nuts and bolts and the installation of incorrect nuts on certain outboard flap support ribs, which could lead to additional nut and bolt damage in the joint, and result in loss of an outboard flap, and adversely affect continued safe flight and landing of the airplane.

Relevant Service Information

We reviewed Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012. For information on the procedures and compliance times, see this service information at http://www.regulations.gov by searching for Docket No. FAA-2013-0301.

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.

Proposed AD Requirements

This proposed AD would require accomplishing the actions specified in the service information described previously.

The phrase “related investigative actions” might be used in this proposed AD. “Related investigative actions” are follow-on actions that (1) are related to the primary action, and (2) are actions that further investigate the nature of any condition found. Related investigative actions in an AD could include, for example, inspections.

In addition, the phrase “corrective actions” might be used in this proposed AD. “Corrective actions” are actions that correct or address any condition found. Corrective actions in an AD could include, for example, repairs.

Costs of Compliance

We estimate that this proposed AD affects 440 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
Detailed inspections	1 work-hour × $85 per hour = $85	$0	$85	$37,400
Replacement of all fasteners (Group 1 airplanes)	2 work-hours × $85 per hour = $170	2,553	2,723	1,198,120

We estimate the following costs to do any necessary related investigative and corrective actions and detailed inspections for nut type that would be required based on the results of the proposed inspections. We have no way of determining the number of aircraft that might need these actions.

On-Condition Costs

Action	Labor cost	Parts cost	Cost per product
Related investigative and corrective actions and detailed inspection for nut type	Up to 3 work-hours × $85 per hour = $255	$2,553	Up to $2,808

According to the manufacturer, some of the costs of this proposed AD may be covered under warranty, thereby reducing the cost impact on affected individuals. We do not control warranty coverage for affected individuals. As a result, we have included all costs in our cost estimate.

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-2013-0301; Directorate Identifier 2013-NM-025-AD.

(a) Comments Due Date

We must receive comments by May 28, 2013.

(b) Affected ADs

None.

(c) Applicability

This AD applies to The Boeing Company Model 767-200, 767-300, 767-300F, and 767-400ER series airplanes; certificated in any category; as identified in Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012.

(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 cracked and corroded nuts on an outboard flap support rib. We are issuing this AD to detect and correct cracked and corroded nuts and bolts and the installation of incorrect nuts on certain outboard flap support ribs, which could lead to additional nut and bolt damage in the joint, and result in loss of an outboard flap, and adversely affect continued safe flight and landing of the airplane.

(f) Compliance

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

(g) For Group 1 Airplanes: Repetitive Inspections of the Support Ribs, Related Investigative and Corrective Actions, and Fastener Replacement

For Group 1 airplanes, as specified in Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012: Except as required by paragraph (j) of this AD, at the time specified in table 1 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012: Do a detailed inspection of the cap seal for damaged sealant on the nuts common to outboard flap support rib numbers 1, 2, 7, and 8, and do all applicable related investigative and corrective actions, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012. Do all applicable related investigative and corrective actions before further flight, except as specified in paragraphs (g)(1)(ii) and (g)(2)(ii) of this AD.

(1) If, during any detailed inspection of the cap seal required by paragraph (g) of this AD, no damaged sealant is found on any support rib, do the actions specified in paragraphs (g)(1)(i) and (g)(1)(ii) of this AD.

(i) Repeat the detailed inspection of the cap seal on that support rib thereafter at the intervals specified in table 1 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012, until all fasteners are replaced within that support rib as required by paragraph (g)(1)(ii) of this AD.

(ii) Except as required by paragraph (j) of this AD, at the time specified in table 1 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012: Replace all fasteners within the support rib in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012.

(2) If, during any related investigative action required by paragraph (g) of this AD, no cracking and no corrosion is found on the nut, bolt, and washers of any support rib, do the actions specified in paragraphs (g)(2)(i) and (g)(2)(ii) of this AD.

(i) Repeat the detailed inspection of the cap seal on that support rib thereafter at the intervals specified in table 1 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012, until all fasteners are replaced within that support rib as required by paragraph (g)(2)(ii) of this AD.

(ii) Except as required by paragraph (j) of this AD, at the time specified in table 1 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012: Replace all fasteners within the support rib in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012.

(h) For Group 2 and 3 Airplanes: Repetitive Inspections of the Support Ribs, Related Investigative and Corrective Actions, and Fastener Replacement

For Group 2 and 3 airplanes, as specified in Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012: Except as required by paragraph (j) of this AD, at the time specified in table 2 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012: Do a detailed inspection of the cap seal for damaged sealant on the nuts common to outboard flap support rib numbers 1, 2, 7, and 8, and do all applicable related investigative and corrective actions, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012. Do all applicable related investigative and corrective actions before further flight.

(1) If, during any detailed inspection of the cap seal required by paragraph (h) of this AD, no damaged sealant is found on any support rib, do the actions specified in paragraphs (h)(1)(i) and (h)(1)(ii) of this AD.

(i) Repeat the detailed inspection of the cap seal on that support rib thereafter at the intervals specified in table 1 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012, until the actions required by paragraph (h)(1)(ii) of this AD are done or until all fasteners are replaced within that support rib as specified in paragraph (i) of this AD.

(ii) Except as required by paragraph (j) of this AD, at the time specified in table 2 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012: Do a detailed inspection to determine the nut type installed in the outboard flap support rib and do all applicable corrective actions, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012. Do all applicable corrective actions before further flight.

(2) If, during any related investigative action required by paragraph (h) of this AD, no cracking and no corrosion is found on the nut, bolt, and washers of any support rib, do the actions specified in paragraphs (h)(2)(i) and (h)(2)(ii) of this AD.

(i) Repeat the detailed inspection of the cap seal on that support rib thereafter at the intervals specified in table 2 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012, until the actions required by paragraph (h)(2)(ii) of this AD are done or until all fasteners are replaced within that support rib as specified in paragraph (i) of this AD.

(ii) Except as required by paragraph (j) of this AD, at the time specified in table 2 of paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012: Do a detailed inspection to determine the nut type installed in the outboard flap support rib and do all applicable corrective actions, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012. Do all applicable corrective actions before further flight.

(i) Replacement of all Fasteners Within Outboard Flap Support Ribs 1, 2, 7, and 8

Replacing all fasteners within outboard flap support rib number 1, 2, 7, or 8, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012, terminates the inspections required by paragraphs (g) and (h) of this AD for that support rib only.

(j) Exception to Service Information

Where Boeing Alert Service Bulletin 767-57A0131, dated October 30, 2012, specifies a compliance time relative to the issue date of that service bulletin, this AD requires compliance within the specified compliance time after the effective date of this AD.

(k) Alternative Methods of Compliance (AMOCs)

(1) The Manager, Seattle Aircraft 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.

(l) Related Information

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

(2) For Boeing service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone [phone], extension 1; fax [phone]; Internet https://www.myboeingfleet.com. You may also 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 March 28, 2013.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.