E9-16575. Airworthiness Directives; Boeing Model 747-100B SUD, -200B, -300, -400, and -400D Series Airplanes

AGENCY:

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

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) that applies to certain Boeing Model 747-100B SUD, -200B, -300, -400, and -400D series airplanes. The existing AD currently requires repetitive inspections for cracking in fuselage stringers 8L, 8R, 10L, and 10R at body stations 460, 480, and 500 frame locations; and repair if necessary. This proposed AD would revise the applicability to include an additional airplane, and reduce compliance times for the initial inspection and repetitive intervals for Model 747-400 series airplanes that have been converted to the large cargo freighter configuration. This proposed AD results from findings of cracking in fuselage stringers 8L, 8R, 10L, and 10R at body stations 460, 480, and 500 frame locations. We are proposing this AD to detect and correct fatigue cracking in certain fuselage stringers, which, if left undetected, could result in fuselage skin cracking that reduces the structural integrity of the skin panel, and consequent rapid depressurization of the airplane.

DATES:

We must receive comments on this proposed AD by August 28, 2009.

ADDRESSES:

You may send comments 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: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed 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. 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 or 425-227-1152.

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 (telephone [phone]) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

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:

Comments Invited

We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include “Docket No. FAA-2009-0636; Directorate Identifier 2009-NM-031-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

On July 13, 2005, we issued AD 2005-15-08, amendment 39-14197 (70 FR 43020, July 26, 2005), for certain Boeing Model 747-100B SUD, -200B, -300, -400, and -400D series airplanes. That AD requires repetitive inspections for cracking in fuselage stringers 8L, 8R, 10L, and 10R at body stations 460, 480, and 500 frame locations; and repair if necessary. That AD resulted from findings of cracking in fuselage stringers 8L, 8R, 10L, and 10R at body stations 460, 480, and 500 frame locations. We issued that AD to detect and correct fatigue cracking in certain fuselage stringers, which, if left undetected, could result in fuselage skin cracking that reduces the structural integrity of the skin panel, and consequent rapid depressurization of the airplane.

Actions Since Existing AD Was Issued

Since we issued AD 2005-15-08, Boeing has revised the service information cited in that AD. AD 2005-15-08 cited Boeing Alert Service Bulletin 747-53A2484, dated June 26, 2003, as the source of service information for the required and optional actions. Revision 1, dated February 12, 2009, adds airplane variable number RS699 to the airplane effectivity; that variable number was inadvertently omitted from Boeing Alert Service Bulletin 747-53A2484, dated June 26, 2003. Also, Model 747-400 series airplanes that have been converted to the large cargo freighter (LCF) configuration (i.e., variable numbers RT631 and RT632) have been moved from Group 3 to a new Group 4 with reduced compliance times for the initial and repetitive inspections, and have revised access instructions due to a different interior configuration. Procedures are otherwise unchanged.

FAA's Determination and Requirements of the Proposed AD

We have evaluated all pertinent information and identified an unsafe condition that is likely to develop on other airplanes of the same type design. For this reason, we are proposing this AD, which would supersede AD 2005-15-08 and would continue to require repetitive inspections for fatigue cracking in fuselage stringers 8L, 8R, 10L, and 10R at body station 460, 480, and 500 frame locations; and repair if necessary. This proposed AD would also revise the applicability to include an additional airplane, and reduce compliance times for initial inspection and repetitive interval for Model 747-400 series airplanes that have been converted to the large cargo freighter configuration.

Change to Existing AD

This proposed AD would retain certain requirements of AD 2005-15-08. Since AD 2005-15-08 was issued, the AD format has been revised, and certain paragraphs have been rearranged. As a result, the corresponding paragraph identifiers have changed in this proposed AD, as listed in the following table:

Revised Paragraph Identifiers

Requirement in AD 2005-15-08	Corresponding requirement in this proposed AD
paragraph (d)	paragraph (e).
paragraph (e)	paragraph (f).
paragraph (f)	paragraph (g).
paragraph (g)	paragraph (k).
paragraph (h)	paragraph (l).
paragraph (i)	paragraph (m).

Costs of Compliance

There are about 246 airplanes of the affected design in the worldwide fleet. The following table provides the estimated costs for U.S. operators to comply with this proposed AD.

Estimated Costs

Action	Work hours	Average labor rate per hour	Cost per airplane	Number of U.S.-registered airplanes	Fleet cost
Inspection (required by AD 2005-15-08)	3	$80	$240 per inspection cycle	69	$16,560 per inspection cycle.
Inspection (proposed)	3	80	$240 per inspection cycle	70	$16,800 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 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); 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 proposed 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

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 amendment 39-14197 (70 FR 43020, July 26, 2005) and adding the following new AD:

Boeing: Docket No. FAA-2009-0636; Directorate Identifier 2009-NM-031-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by August 28, 2009.

Affected ADs

(b) This AD supersedes AD 2005-15-08.

Applicability

(c) This AD applies to Boeing Model 747-100B SUD, -200B, -300, -400, and -400D series airplanes, certificated in any category; as identified in Boeing Service Bulletin 747-53A2484, Revision 1, dated February 12, 2009.

Subject

(d) Air Transport Association (ATA) of America Code 53: Fuselage.

Unsafe Condition

(e) This AD results from findings of cracking in fuselage stringers 8L, 8R, 10L, and 10R at body station 460, 480, and 500 frame locations. We are issuing this AD to detect and correct fatigue cracking in the specified fuselage stringers, which, if left undetected, could result in fuselage skin cracking that reduces the structural integrity of the skin panel, and consequent rapid depressurization of the airplane.

Compliance

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

Requirements of AD 2005-15-08

Inspection for Certain Airplanes Subject to AD 2005-15-08 With New Service Bulletin

(g) For airplanes identified in Boeing Alert Service Bulletin 747-53A2484, dated June 26, 2003, except airplanes identified in paragraph (j) of this AD, do a detailed inspection for cracking in fuselage stringers 8L, 8R, 10L, and 10R at body station 460, 480, and 500 frame locations, in accordance with Part 1 of the Accomplishment Instructions in Boeing Alert Service Bulletin 747-53A2484, dated June 26, 2003; or Boeing Service Bulletin 747-53A2484, Revision 1, dated February 12, 2009. Do the inspections at the applicable time specified in paragraph (g)(1) or (g)(2) of this AD. Repeat the inspection thereafter at intervals not to exceed 3,000 flight cycles until the requirements of paragraph (l) of this AD are accomplished. After the effective date of this AD, use only Boeing Service Bulletin 747-53A2484, Revision 1, dated February 12, 2009.

(1) For airplanes with 19,000 total flight cycles or less as of August 30, 2005 (the effective date of AD 2005-15-08): Prior to the accumulation of 8,000 total flight cycles, or within 2,000 flight cycles after August 30, 2005, whichever is later, not to exceed 20,000 total flight cycles.

(2) For airplanes with more than 19,000 total flight cycles as of August 30, 2005: Within 1,000 flight cycles after August 30, 2005.

Note 1:

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 mirror, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate procedures may be required.”

New Requirements of This Ad

Inspection: Variable Number RS699

(h) For Model 747 airplane variable number RS699, do a detailed inspection for cracking in fuselage stringers 8L, 8R, 10L, and 10R at body station 460, 480, and 500 frame locations, in accordance with Boeing Service Bulletin 747-53A2484, Revision 1, dated February 12, 2009, at the later of the times specified in paragraphs (h)(1) and (h)(2) of this AD.

(1) Before the accumulation of 8,000 total flight cycles.

(2) Within 2,000 flight cycles after the effective date of this AD.

(i) For Model 747 airplane variable number RS699, repeat the inspection specified in paragraph (h) of this AD thereafter at intervals not to exceed 3,000 flight cycles until the actions specified in paragraph (k) or (l) of this AD are accomplished.

Inspection: Group 4 Airplanes

(j) For Group 4 airplanes as identified in Boeing Service Bulletin 747-53A2484, Revision 1, dated February 12, 2009, do a detailed inspection for cracking in fuselage stringers 8L, 8R, 10L, and 10R at body station 460, 480, and 500 frame locations, within 1,000 flight cycles after the effective date of this AD. Do the actions in accordance with Boeing Service Bulletin 747-53A2484, Revision 1, dated February 12, 2009. Repeat the inspection thereafter at intervals not to exceed 1,500 flight cycles until the actions specified in paragraph (k) or (l) of this AD are accomplished.

Repair

(k) If cracking is found during any inspection required by this AD: Before further flight, repair the affected stringer in accordance with Part 2 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2484, dated June 26, 2003; or Boeing Service Bulletin 747-53A2484, Revision 1, dated February 12, 2009. After the effective date of this AD, use only Boeing Service Bulletin 747-53A2484, Revision 1, dated February 12, 2009. Accomplishment of the repair terminates the repetitive inspections required by this AD for that repaired stringer/frame location only.

Optional Terminating Action

(l) Installing new frame clips and new doublers, and repairing as applicable, in accordance with Part 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2484, dated June 26, 2003; or Boeing Service Bulletin 747-53A2484, Revision 1, dated February 12, 2009; terminates the repetitive inspections required by this AD. After the effective date of this AD, use only Boeing Service Bulletin 747-53A2484, Revision 1, dated February 12, 2009.

Alternative Methods of Compliance (AMOCs)

(m)(1) The Manager, Seattle ACO, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: 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]; or e-mail information to [e-mail].

(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 principal maintenance inspector (PMI) or principal avionics inspector (PAI), as appropriate, or lacking a principal inspector, your local Flight Standards District Office. The AMOC approval letter must specifically reference this AD.

(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 2005-15-08, amendment 39-14197, are approved as AMOCs for the corresponding provisions of this AD.

Issued in Renton, Washington, on July 2, 2009.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.