Federal Aviation Administration (FAA), Department of Transportation (DOT).
Notice of proposed rulemaking (NPRM).
The FAA proposes to adopt a new airworthiness directive (AD) for all Boeing Model 747-200F, 747-200C, 747-400, 747-400D, and 747-400F series airplanes. This proposed AD would require repetitive inspections for cracking of certain fuselage internal structure, and repair if necessary. This proposed AD is prompted by fatigue tests and analysis that identified areas of the fuselage where fatigue cracks can occur. We are proposing this AD to prevent loss of the structural integrity of the fuselage, which could result in rapid depressurization of the airplane.
We must receive comments on this proposed AD by November 14, 2005.
Use one of the following addresses to submit comments on this proposed AD.
- DOT Docket Web Site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
- Government-wide rulemaking Web Site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically.
- Mail: Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., Nassif Building, room PL-401, Washington, DC 20590.
- By Fax: (202) 493-2251.
- Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street SW., Washington, DC, 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, P.O. Box 3707, Seattle, Washington 98124-2207.
You can examine the contents of this AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., room PL-401, on the plaza level of the Nassif Building, Washington, DC. This docket number is FAA-2005-22526; the directorate identifier for this docket is 2005-NM-008-AD.Start Further Info
FOR FURTHER INFORMATION CONTACT:
Ivan Li, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 917-6437; fax (425) 917-6590.End Further Info End Preamble Start Supplemental Information
We invite you to submit any relevant written data, views, or arguments regarding this proposed AD. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2005-22526; Directorate Identifier 2005-NM-008-AD” in the subject line of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments submitted by the closing date and may amend the proposed AD in light of those comments.
We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this proposed AD. Using the search function of that Web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You can review DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you can visit http://dms.dot.gov.
Examining the Docket
You can examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647-5227) is located on the plaza level of the Nassif Building at the DOT street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after the DMS receives them.
Boeing has completed extended pressure fatigue tests on a Boeing Model 747SR and a 747-400 fuselage test article. Boeing has also used updated analysis methods on the 747 fuselage structure. The tests and analysis have identified areas of the fuselage where fatigue cracks can occur. This condition, if not corrected, could result in loss of the structural integrity of the fuselage and consequent rapid depressurization of the airplane.
On May 14, 2002, we issued AD 2002-10-10, amendment 39-12756 (67 FR 36081, May 23, 2002). That AD applies to certain Boeing Model 747 airplanes. That AD requires repetitive inspections to detect cracks in various areas of the fuselage internal structure, and repair if necessary. This proposed AD would require similar inspections for Model 747 airplanes that are not identified in the applicability of AD 2002-10-10.
We also issued AD 2004-07-22, amendment 39-13566 (69 FR 18250, April 7, 2004), as corrected (69 FR 19618, April 13, 2005), and as further corrected (69 FR 24063, May 3, 2005). That AD applies to all Boeing Model 747 series airplanes and requires that the FAA-approved maintenance inspection program be revised to include inspections that will give no less than the required damage tolerance rating for each structural significant item, and repair of cracked structure.
Relevant Service Information
We have reviewed Boeing Alert Service Bulletin 747-53A2500, dated December 21, 2004. Procedures for repetitive inspections for cracks are listed in the following table:Start Printed Page 56861
|The service bulletin describes procedures for—||Of the—|
|Internal detailed inspections||Upper deck floor beams; Section 42 frames; Section 46 frames; and Nose wheel well bulkheads, sidewall panels, and the STA 360 and 380 main deck floor beams.|
|Internal and external detailed inspections||Main entry doors and door cutouts; and Fuselage skin at all four corners of the main electronics bay access door cutout.|
The compliance threshold is 22,000 or 25,000 total flight cycles (depending on the inspection area and airplane configuration), with a repetitive interval of 3,000 flight cycles. The service bulletin recommends repairing cracks by using the structural repair manual (SRM) or contacting Boeing. Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition.
FAA's Determination and Requirements of the Proposed AD
We have evaluated all pertinent information and identified an unsafe condition that is likely to exist or develop on other airplanes of this same type design. Therefore, we are proposing this AD, which would require accomplishing the actions specified in the service information described previously, except as discussed below.
Differences Between the Proposed AD and the Service Bulletin
The service bulletin specifies compliance times relative to the date of issuance of the service bulletin; however, this proposed AD would require compliance before the specified compliance times relative to the effective date of this AD.
Also, the service bulletin specifies contacting the manufacturer for instructions on how to repair certain conditions, but this proposed AD would require you to repair those conditions by using a method that we approve, or using data that meet the certification basis of the airplane and that have been approved by an Authorized Representative for the Boeing Delegation Option Authorization Organization whom we have authorized to make those findings.
Costs of Compliance
There are about 706 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.
|Action||Work hours||Average labor rate per hour||Parts||Cost per airplane||Number of U.S.-registered airplanes||Fleet cost|
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.
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. See the ADDRESSES section for a location to examine the regulatory evaluation.Start List of Subjects
List of Subjects in 14 CFR Part 39
- Air transportation
- Aviation 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:Start Part
PART 39—AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):
Boeing: Docket No. FAA-2005-22526; Directorate Identifier 2005-NM-008-AD.Start Printed Page 56862
Comments Due Date
(a) The Federal Aviation Administration (FAA) must receive comments on this AD action by November 14, 2005.
(b) Inspections specified in this AD may be considered an alternative method of compliance (AMOC) for certain requirements of AD 2004-07-22, as specified in paragraph (i)(2) of this AD.
(c) This AD applies to all Boeing Model 747-200F, 747-200C, 747-400, 747-400D, and 747-400F series airplanes; certificated in any category.
(d) This AD was prompted by fatigue tests and analysis that identified areas of the fuselage where fatigue cracks can occur. We are issuing this AD to prevent loss of the structural integrity of the fuselage, which could result in rapid depressurization of the airplane.
(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.
(f) Except as required/provided by paragraphs (g) and (h) of this AD: Do initial and repetitive inspections for fuselage cracks using applicable internal and external detailed inspection methods, and repair all cracks, by doing all the actions specified in the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2500, dated December 21, 2004. Do the initial and repetitive inspections at the times specified in paragraph 1.E. of the service bulletin. Repair any crack before further flight after detection.
Exceptions to Service Bulletin Procedures
(g) If any crack is found during any inspection required by this AD, and the bulletin specifies to contact Boeing for appropriate action: Before further flight, repair the crack according to a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or according to data meeting the certification basis of the airplane approved by an Authorized Representative for the Boeing 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, and the approval must specifically reference this AD.
(h) Where the service bulletin specifies a compliance time after the issuance of the service bulletin, this AD requires compliance within the specified compliance time after the effective date of this AD.
(i)(1) The Manager, Seattle Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.
(2) Accomplishment of the inspections specified in this AD is considered an AMOC for the applicable requirements of paragraphs (c) and (d) of AD 2004-07-22, amendment 39-13566, under the following conditions:
(i) The actions must be done within the compliance times specified in AD 2004-07-22. The initial inspection must be done at the times specified in paragraph (d) of AD 2004-07-22, and the inspections must be repeated within the intervals specified in paragraph (f) of this AD.
(ii) The AMOC applies only to the areas of Supplemental Structural Inspection Document D6-35022, Revision G, that are specified in Boeing Alert Service Bulletin 747-53A2500, dated December 21, 2004.
(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 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, and the approval must specifically refer to this AD.
(4) Before using any AMOC approved in accordance with § 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.
Issued in Renton, Washington, on September 16, 2005.
Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 05-19239 Filed 9-28-05; 8:45 am]
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