AD 2017-18-06

This AD is effective October 5, 2017.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of October 5, 2017.

The Director of the Federal Register approved the incorporation by reference of a certain other publication listed in this AD as of April 24, 2012 (77 FR 16143, March 20, 2012).

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 562-797-1717; Internet https://www.myboeingfleet.com. You may view this service information at the FAA, Transport Standards Branch, 1601 Lind Avenue SW., Renton, WA. For information on the availability of this material at the FAA, call 425-227-1221. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2017-0247.

Tung Tran, Aerospace Engineer, Propulsion Section, Seattle ACO Branch, FAA, 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6505; fax: 425-917-6590; email: Tung.Tran@faa.gov.

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2012-05-03, Amendment 39-16975 (77 FR 16143, March 20, 2012) (“AD 2012-05-03”). AD 2012-05-03 applied to certain The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SR, and 747SP series airplanes. The NPRM published in the Federal Register on April 11, 2017 (82 FR 17403). The NPRM was prompted by a design review following a ground fire incident and reports of flammable fluid leaks from the wing leading edge area onto the engine exhaust area. The NPRM proposed to continue to require modifying the fluid drain path in the leading edge area of the wing. The NPRM also proposed to require additional work to seal those drainage holes in the wing access panels. We are issuing this AD to prevent flammable fluid from leaking onto the engine exhaust nozzle, which could result in a fire.

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM or on the determination of the cost to the public.

We reviewed the relevant data and determined that air safety and the public interest require adopting this AD as proposed, except for minor editorial changes. We have determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and

• Do not add any additional burden upon the public than was already proposed in the NPRM.

We reviewed Boeing Special Attention Service Bulletin 747-57-2332, Revision 2, dated February 22, 2016. This service information divides the affected airplanes into 10 groups.

For all groups, this service information describes procedures for modifying the fluid drain path in the leading edge area of the wing. The modification consists of changing fluid dam assemblies at wing outboard leading edge station (OLES) 1250, and installing seal assemblies at OLES 1185. Additionally, this service information specifies changing the lower leading edge wing panels through repairs and installation of parts.

For Groups 1 through 6 airplanes, this service information also specifies installing fluid dam assemblies at wing OLES 770.

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.

We estimate that this AD will affect 258 airplanes of U.S. registry. We estimate the following costs to comply with this AD:

According to the manufacturer, some of the costs of this 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.

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.

This 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 to the Director of the System Oversight Division.

We have determined that 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) Is not a “significant rule” under 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.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

1. The authority citation for part 39 continues to read as follows:

2. The FAA amends § 39.13 by removing Airworthiness Directive (AD) 2012-05-03, Amendment 39-16975 (77 FR 16143, March 20, 2012), and adding the following new AD: