E9-3272. Airworthiness Directives; Boeing 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

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Final rule.

SUMMARY:

The FAA is superseding an existing airworthiness directive (AD), which applies to all Boeing Model 747 series airplanes. That AD currently requires repetitive detailed inspections of the aft pressure bulkhead for indications of “oil cans” and previous oil can repairs, and corrective actions if necessary. An oil can is an area on a pressure dome web that moves when pushed from the forward side. This new AD requires a reduced compliance time for the initial detailed inspection and revises the applicability. This AD results from a report that cracks in oil-canned areas were found during an inspection of the aft pressure bulkhead. We are issuing this AD to detect and correct the propagation of fatigue cracks in the vicinity of oil cans on the web of the aft pressure bulkhead, which could result in rapid decompression of the airplane and overpressurization of the tail section, and consequent loss of control of the airplane.

DATES:

This AD becomes effective April 2, 2009.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in the AD as of April 2, 2009.

On September 13, 2004 (69 FR 48133, August 9, 2004), the Director of the Federal Register approved the incorporation by reference of a certain other publication.

ADDRESSES:

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; telephone [phone], extension 1; fax [phone]; e-mail [e-mail]; Internet https://www.myboeingfleet.com.

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 AD, the regulatory evaluation, any comments received, and other information. The address for the Docket Office (telephone [phone]) is the Document Management Facility, U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT:

Ivan Li, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Discussion

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that supersedes AD 2004-16-09, amendment 39-13765 (69 FR 48133, August 9, 2004). The existing AD applies to all Boeing Model 747 series airplanes. That NPRM was published in the Federal Register on July 2, 2008 (73 FR 37900). That NPRM proposed to require a reduced initial threshold for repetitive detailed inspections of the aft pressure bulkhead for indications of “oil cans” and previous oil can repairs, and corrective actions if necessary.

Comments

We provided the public the opportunity to participate in the development of this AD. We have considered the comments that have been received on the NPRM. Two commenters, the Air Line Pilots Association, International (ALPA), and Northwest Airlines, support the NPRM.

Request to Remove Certain Airplanes From Applicability Section

Boeing requests that we remove Model 747-400 airplanes with the following variable numbers from paragraph (c) of this proposed AD: RT631, RT632, RT743, and RT876. Those airplanes have been or are being converted to a 747-400 LCF (large cargo freighter) configuration. The aft pressure bulkhead is removed from these airplanes; therefore, the proposed AD would not apply to those airplanes.

We agree that airplanes that have been converted to a Model 747-400 LCF configuration no longer have an aft pressure bulkhead to inspect. We have revised the applicability section of this AD to exclude airplanes that have been converted. We have not excluded specific variable numbers as suggested by Boeing since more airplanes might be converted to the Model 747-400 LCF configuration in the future.

Explanation of Change to Paragraph (f) of This AD

We have removed the “Service Bulletin Reference” paragraph from this AD. (That paragraph was identified as paragraph (f) in the NPRM.) Instead, we have spelled out the service bulletin citations throughout this AD. We also re-identified the subsequent paragraphs.

Conclusion

We have carefully reviewed the available data, including the comments that have been received, and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

There are about 917 airplanes of the affected design in the worldwide fleet. This AD affects about 165 airplanes of U.S. registry.

The actions that are required by AD 2004-16-09 and retained in this AD take about 2 work hours per airplane, at an average labor rate of $80 per work hour. Based on these figures, the estimated cost of the currently required actions to the U.S. operators is $26,400, or $160 per airplane, per inspection cycle.

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 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); and

(3) 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.

We prepared a regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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 Federal Aviation Administration (FAA) amends § 39.13 by removing amendment 39-13765 ( 69 FR 48133, August 9, 2004) and by adding the following new airworthiness directive (AD):

2009-04-06 Boeing: Amendment 39-15812. Docket No. FAA-2008-0731; Directorate Identifier 2008-NM-058-AD.

Effective Date

(a) This AD becomes effective April 2, 2009.

Affected ADs

(b) This AD supersedes AD 2004-16-09.

Applicability

(c) This AD applies to Boeing 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, certificated in any category, except those that have been converted to a Model 747-400 LCF configuration.

Unsafe Condition

(d) This AD results from a report that cracks in oil-canned areas were found during an inspection of the aft pressure bulkhead. We are issuing this AD to detect and correct the propagation of fatigue cracks in the vicinity of oil cans on the web of the aft pressure bulkhead, which could result in rapid decompression of the airplane and overpressurization of the tail section, and consequent loss of control of the airplane.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Note 1:

This AD refers to certain portions of Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002; and Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008; for inspections and repair information. In addition, this AD specifies requirements beyond those included in Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002; and Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008. Where the AD and Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002; and Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008; differ, the AD prevails.

Requirements of AD 2004-16-09, With Reduced Threshold

Initial and Repetitive Inspections

(f) At the earlier of the times specified in paragraphs (f)(1) and (f)(2) of this AD, perform a detailed inspection of the aft pressure bulkhead for indications of oil cans and previous oil can repairs, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002; or Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008. After the effective date of this AD, Revision 1 must be used.

(1) Prior to the accumulation of 30,000 total flight cycles, or within 1,000 flight cycles after September 13, 2004 (the effective date of AD 2004-16-09), whichever is later.

(2) Prior to the accumulation of 20,000 total flight cycles, or within 1,000 flight cycles after the effective date of this AD, whichever occurs later.

Note 2:

For the purposes of this AD, a detailed inspection is “an intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirrors, magnifying lenses, etc. may be necessary. Surface cleaning and elaborate procedures may be required.”

(g) If no indication of an oil can is found and no indication of a previous oil can repair is found during the detailed inspection required by paragraph (f) of this AD, repeat the detailed inspection thereafter at intervals not to exceed 2,000 flight cycles.

Indication of Oil Can

(h) If any indication of an oil can is found during the detailed inspection required by paragraph (f) or (g) of this AD, before further flight, perform an eddy current inspection of the web around the periphery of the oil can indication for cracks, as shown in Figure 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002; or Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008. After the effective date of this AD, Revision 1 must be used.

(i) If no crack is found during the eddy current inspection required by paragraph (i) of this AD, do the actions specified in paragraph (i)(1) or (i)(2) of this AD, as applicable.

(1) For the oil can that meets the allowable limits specified in Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002; or Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008: Repeat the eddy current inspection specified in paragraph (h) of this AD thereafter at intervals not to exceed 1,000 flight cycles. As an option, repair the oil can in accordance with paragraph (i)(2) of this AD.

(2) For the oil can that does not meet the allowable limits specified in Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002; or Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008: Before further flight, repair the oil can in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002; or Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008. After the effective date of this AD, Revision 1 must be used. If the repair eliminates the oil can, accomplishment of this repair constitutes terminating action for the repetitive eddy current inspection requirements of paragraph (i)(1) of this AD for that location only. However, the repetitive detailed inspection required by paragraph (g) of this AD is still required. If any oil can remains after the repair, repeat the eddy current inspection specified in paragraph (h) of this AD thereafter at intervals not to exceed 1,000 flight cycles.

Indication of Previous Oil Can Repairs

(j) If any previous oil can repair is found during the detailed inspection required by paragraph (f) or (g) of this AD, before further flight, do a detailed inspection of the web for cracks and oil cans, as shown in Figure 4 or Figure 5, as applicable, of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002; or Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008. After the effective date of this AD, Revision 1 must be used.

(1) If no crack and no oil can are found, repeat the detailed inspection in accordance with paragraph (f) of this AD.

(2) If any oil can is found, before further flight, do the eddy current inspection for cracks, as shown in Figure 3 of Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002; or Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008. After the effective date of this AD, Revision 1 must be used. If no crack is found during the eddy current inspection required by this paragraph, do the actions specified in paragraph (i)(1) or (i)(2) of this AD, as applicable, at the time specified in the applicable paragraph.

Repair of Cracks

(k) If any crack is found during any inspection required by this AD, before further flight, repair in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002; or Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008. After the effective date of this AD, Revision 1 must be used. If any crack or damage exceeds limits specified in Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002; or Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008; and Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002; or Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008; specifies to contact Boeing for appropriate action: Before further flight, repair per a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or per data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative who has been authorized by the Manager, Seattle ACO, to make such findings; or using a method approved in accordance with the procedures specified in paragraph (m) of this AD. For a repair method to be approved, the approval must specifically reference this AD.

New Requirements of This AD

(l) As of the effective date of this AD, if any crack or damage is found during any inspection required by this AD, and Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008, specifies to contact Boeing for appropriate action (repair data): Before further flight, repair the crack or damage using a method approved in accordance with the procedures specified in paragraph (m) of this AD.

Alternative Methods of Compliance (AMOCs)

(m)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, ATTN: Ivan Li, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle ACO, 1601 Lind Avenue SW., Renton, Washington 98057-3356; telephone [phone]; fax [phone], has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19.

(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.

(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 an Authorized Representative for the Boeing Commercial Airplanes Delegation Option Authorization Organization who 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.

(4) AMOCs approved previously in accordance with AD 2004-16-09 are not approved as AMOCs for the corresponding provisions of paragraph (f) of this AD. They are approved as AMOCs for the corresponding provisions of paragraphs (g), (h), (i), (j), (k), and (l) of this AD.

Material Incorporated by Reference

(n) You must use Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002; or Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008; as applicable; to perform the actions that are required by this AD, unless the AD specifies otherwise.

(1) The Director of the Federal Register approved the incorporation by reference of Boeing Alert Service Bulletin 747-53A2482, Revision 1, dated February 21, 2008, in accordance with 5 U.S.C. 552(a) and 1 CFR part 51.

(2) On September 13, 2004 (69 FR 48133, August 9, 2004), the Director of the Federal Register approved the incorporation by reference of Boeing Alert Service Bulletin 747-53A2482, dated October 3, 2002.

(3) Contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone [phone], extension 1; fax [phone]; e-mail [e-mail]; Internet https://www.myboeingfleet.com;​; for a copy of this service information.

(4) You may review copies of the 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 or 425-227-1152.

(5) You may also review copies of the service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/​federal_​register/​code_​oflowbar;​federal_​regulations/​ibr_​locations.html.

Issued in Renton, Washington, on January 29, 2009.

Stephen P. Boyd,

Assistant Manager, Transport Airplane Directorate, Aircraft Certification Service.