2018-14398. Airworthiness Directives; The Boeing Company Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM); removal of airworthiness directive (AD).

SUMMARY:

We propose to remove AD 93-14-19, which applies to certain The Boeing Company Model 767-200 and -300 series airplanes. AD 93-14-19 requires inspections for disbonding of the trailing edge wedge of the leading edge slat; and repair, if necessary. Since we issued AD 93-14-19, an updated stability and control analysis showed that the worst-case scenario of a trailing edge wedge disbond in-flight would not adversely affect the controllability of the airplane. Accordingly, we propose to remove AD 93-14-19.

DATES:

We must receive comments on this proposed AD by August 31, 2018.

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.

Examining the AD Docket

You may examine the AD docket on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2018-0582; 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 proposal, any comments received, and other information. The street address for Docket Operations (phone: [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT:

Wayne Lockett, Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 98198; phone and 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-2018-0582; Product Identifier 2018-NM-085-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 AD 93-14-19, Amendment 39-8644 (58 FR 41177, August 3, 1993) (“AD 93-14-19”), for certain The Boeing Company Model 767-200 and -300 series airplanes. AD 93-14-19 requires visual inspections and either “Coin Tap” inspections or ultrasonic inspections for disbonding of the trailing edge wedge of the leading edge slat, and repair, if necessary. AD 93-14-19 resulted from reports of wedge damage or disbonding; in two cases the damage resulted in loss of a portion of the trailing edge wedge. The trailing edge wedge disbonding was caused by moisture ingression at the wedge end seals and in the skin bonds along the spar chords. Moisture in the aluminum honeycomb core would cause corrosion that would eventually result in disbonding between the skin and the aluminum honeycomb core. We issued AD 93-14-19 to prevent the loss of a trailing edge wedge, which could result in reduced maneuver margins, reduced speed margins to stall, and unexpected roll before stall warning, all of which would adversely affect the controllability of the airplane.

Actions Since AD 93-14-19 Was Issued

Since we issued AD 93-14-19, an updated stability and control analysis showed that the worst-case scenario of a trailing edge wedge disbond in-flight would not adversely affect the controllability of the airplane. Simulation analysis shows that the airplane has sufficient lateral control up to the stick shaker to counter the rolling moment caused by a trailing edge wedge loss, at all flap settings. Therefore, the unsafe condition no longer exists on these products worldwide.

FAA's Conclusions

Upon further consideration, we have determined that AD 93-14-19 must be removed. Accordingly, this proposed AD would remove AD 93-14-19. Removal of AD 93-14-19 would not preclude the FAA from issuing another related action or commit the FAA to any course of action in the future.

Related Costs of Compliance

AD 93-14-19 affects approximately 180 airplanes of U.S. registry. The estimated costs for the actions required by AD 93-14-19 for U.S. operators is $79,200, or $440 per airplane. Removing AD 93-14-19 would eliminate those costs.

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.

This proposed AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to transport category airplanes and associated appliances to the Director of the System Oversight Division.

Regulatory Findings

We have 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 that the 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 removing Airworthiness Directive (AD) AD 93-14-19, Amendment 39-8644 ( 58 FR 41177, August 3, 1993), and adding the following new AD:

The Boeing Company: Docket No. FAA-2018-0582; Product Identifier 2018-NM-085-AD.

(a) Comments Due Date

The FAA must receive comments on this AD action by August 31, 2018.

(b) Affected ADs

This AD removes AD 93-14-19, Amendment 39-8644 (58 FR 41177, August 3, 1993).

(c) Applicability

This AD applies to The Boeing Company Model 767 series airplanes, certificated in any category, line numbers 1 through 488 inclusive.

(d) Subject

Air Transport Association (ATA) of America Code 57, Wings.

(e) Related Information

For more information about this AD, contact Wayne Lockett, Aerospace Engineer, Airframe Section, FAA, Seattle ACO Branch, 2200 South 216th St., Des Moines, WA 98198; phone and fax: [phone]; email: [e-mail].

Issued in Des Moines, Washington, on June 22, 2018.

Michael Kaszycki,

Acting Director, System Oversight Division, Aircraft Certification Service.