AD 2016-01-04

This AD is effective February 17, 2016.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of February 17, 2016.

For 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 206-544-5000, extension 1; fax 206-766-5680; Internet https://www.myboeingfleet.com. You may view this referenced service information at the FAA, Transport Airplane Directorate, 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-2015-1984.

Nathan Weigand, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6428; fax: 425-917-6590; email: nathan.p.weigand@faa.gov.

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2005-01-09, Amendment 39-13933 (70 FR 1340, January 7, 2005). AD 2005-01-09 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, and 747SR series airplanes. The NPRM published in the Federal Register on June 24, 2015 (80 FR 36255) (“the NPRM”). The NPRM was prompted by additional cracking found in the same area after completion of the one-time detailed inspection. The NPRM proposed to continue to require a one-time detailed inspection for discrepancies of the frame web and inner chords on the forward edge frame of the number 5 main entry door cutout, and corrective action if necessary. The NPRM also proposed to require repetitive HFEC inspections for cracking of the frame inner chords (forward and aft), and corrective action if necessary. We are issuing this AD to detect and correct discrepancies of the frame web and inner chords, which could result in cracking, subsequent severing of the frame, and consequent rapid depressurization of the airplane.

We gave the public the opportunity to participate in developing this AD. The following presents the comments received on the NPRM and the FAA's response to each comment. United Airlines concurred with the NPRM.

UPS asked that credit be included in the proposed AD (80 FR 36255, June 24, 2015) for accomplishing the inspections required by AD 2013-17-08. UPS stated that paragraph (g) of the proposed AD would require accomplishing the same inspections that are required by AD 2013-17-08. UPS added that the proposed AD has a lower threshold for accomplishing the inspections than that in AD 2013-17-08. UPS noted that Boeing confirmed that these inspections are duplicated and stated that a revision of the service information may be forthcoming to provide clarification.

We agree with the commenter that accomplishing the inspections required by AD 2013-17-08 before the effective date of this AD is acceptable for compliance with the inspections required by this AD. We had already included credit for accomplishing the inspections required by AD 2013-17-08 in paragraph (i)(2) of the proposed AD.

However, since the compliance time in AD 2013-17-08 is later than the compliance time required by this AD, we have not given credit for inspections that will be done for AD 2013-17-08 on or after the effective date of this AD. Operators may apply for approval of an AMOC in accordance with the provisions specified in paragraph (j) of this AD, by submitting data substantiating that the request would provide an acceptable level of safety. Therefore, we have made no further change to this AD.

UPS also recommended adding a sentence to paragraph (h) of the proposed AD to terminate the repetitive inspections required by AD 2013-17-08, after accomplishment of the initial inspections required by the proposed AD.

We do not agree to specify that the actions required by paragraph (h) of this AD terminate the repetitive inspections required by AD 2013-17-08, because those inspections are more extensive than the inspections in this AD. However, affected operators who wish to terminate the repetitive inspections required by AD 2013-17-08 may apply for approval of an AMOC in accordance with the provisions specified in paragraph (j) of this AD, by submitting data substantiating that the request would provide an acceptable level of safety. We have not changed this AD in this regard.

Boeing asked that a typographical error in the “Related AD” section of the proposed AD be corrected. Boeing stated that the description of the inspection area in AD 2013-17-08 of the frame segment should be changed from “between 16 and 31” to “between 15 and 31.” Boeing noted that this is a typographical error.

We agree that there is a typographical error in the “Related AD” section of the proposed AD, as noted by the commenter. That section should specify “the frame segment between 15 and 31”; however, since that section of the preamble does not reappear in the final rule, no change to this AD is necessary in this regard.

We reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this AD as proposed, with 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 and approved Boeing Alert Service Bulletin 747-53A2494, Revision 1, dated January 9, 2015. The service information describes procedures for a one-time detailed inspection and repetitive surface HFEC inspections of the Station 2231 frame inner chords (forward and aft), and repair of discrepancies. 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 affects 174 airplanes of U.S. registry.

We estimate the following costs to comply with this AD:

We have received no definitive data that will enable us to provide a cost estimate for the on-condition actions specified in this AD.

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.

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) 2005-01-09, Amendment 39-13933 (70 FR 1340, January 7, 2005), and adding the following new AD: