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Proposed Rule

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

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

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AGENCY:

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

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for certain Boeing Model 747-100B SUD, 747-200B, 747-300, 747-400, 747-400D, and 747SP series airplanes. This proposed AD would require repetitive inspections for cracking of the crease beam and adjacent intercostals, stringers, frames, and skin panels; and related investigative and corrective actions if cracking is found. This proposed AD results from a report indicating that an operator discovered crease beam cracking on two Model 747 airplanes. We are proposing this AD to detect and correct cracking of the crease beam and adjacent structure, which could become large and result in in-flight depressurization and inability of the airframe structure to sustain flight loads.

DATES:

We must receive comments on this proposed AD by September 22, 2006.

ADDRESSES:

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.
  • 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.

Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207, for the service information identified in this proposed AD.

Start Further Info

FOR FURTHER INFORMATION CONTACT:

Nicholas Kusz, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 917-6432; fax (425) 917-6590.

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SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any relevant written data, views, or arguments regarding this proposed AD. Send your comments to an address listed in the ADDRESSES section. Include the docket number “FAA-2006-22518; Directorate Identifier 2006-NM-092-AD” at the beginning 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 received 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 may review DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you may visit http://dms.dot.gov.

Examining the Docket

You may 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 Docket Management System receives them.

Discussion

We have received a report indicating that an operator discovered crease beam cracking due to fatigue on two Model 747 airplanes during inspections specified in the 747 Supplemental Structural Inspection Document. This condition, if not detected and corrected, could cause in-flight depressurization and inability of the structure to sustain flight loads.

Relevant Service Information

We have reviewed Boeing Alert Service Bulletin 747-53A2591, dated April 6, 2006. The service bulletin describes procedures for performing repetitive detailed inspections for cracking of the crease beam and adjacent intercostals, stringers, frames, and skin panels; and related investigative and corrective actions if cracking is found. Related investigative actions include performing a surface high-frequency eddy current (HFEC) inspection for cracking of the adjacent skin panel fastener locations, including all skin fasteners common to the crease beam in the areas between the next fuselage frame directly forward and aft of the crack location. Corrective actions include repair of any crack before further flight. If any crack is outside the limits specified in the Boeing 747 Structural Repair Manual, the service bulletin specifies to contact the manufacturer for repair data. The service bulletin also:

  • Describes procedures for submitting a report if any skin panel or more than two intercostal webs or skin panel fastener clips are found to be cracked;
  • Specifies a compliance time of 14,000 total flight cycles or 1,500 flight cycles after the date of the service bulletin, whichever occurs later; and Start Printed Page 44934
  • Specifies an interval of 6,000 flight cycles for performing the repetitive inspections.

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. For this reason, we are proposing this AD, which would require accomplishing the actions specified in the service information described previously, except as discussed under “Differences Between the Proposed AD and Service Bulletin.”

Differences Between the Proposed AD and Service Bulletin

The service bulletin specifies to contact the manufacturer for instructions on how to repair certain conditions, but this proposed AD would require repairing those conditions in one of the following ways:

  • 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 Commercial Airplanes Delegation Option Authorization Organization whom we have authorized to make those findings.

Although the Accomplishment Instructions of the service bulletin describe procedures for submitting certain information to the manufacturer, this proposed AD would not require those actions.

Costs of Compliance

There are about 615 airplanes of the affected design in the worldwide fleet. This proposed AD would affect about 65 airplanes of U.S. registry. The proposed detailed inspection would take about 8 work hours per airplane, per inspection cycle, at an average labor rate of $80 per work hour. Based on these figures, the estimated cost of the proposed AD for U.S. operators is $41,600, or $640 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 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.

Start List of Subjects

List of Subjects in 14 CFR Part 39

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The Proposed Amendment

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

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PART 39—AIRWORTHINESS DIRECTIVES

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

Start Authority

Authority: 49 U.S.C. 106(g), 40113, 44701.

End Authority
[Amended]

2. The Federal Aviation Administration (FAA) amends § 39.13 by adding the following new airworthiness directive (AD):

Boeing: Docket No. FAA-2006-22518; Directorate Identifier 2006-NM-092-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by September 22, 2006.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Boeing Model 747-100B SUD, 747-200B, 747-300, 747-400, 747-400D, and 747SP series airplanes, certificated in any category; as identified in Boeing Alert Service Bulletin 747-53A2591, dated April 6, 2006 (referred to after this paragraph as “the service bulletin”).

Unsafe Condition

(d) This AD results from a report indicating that an operator discovered crease beam cracking on two Model 747 airplanes. We are issuing this AD to detect and correct cracking of the crease beam and adjacent structure, which could become large and result in in-flight depressurization and inability of the airframe structure to sustain flight loads.

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.

Repetitive Detailed Inspections and Related Investigative and Corrective Actions

(f) Perform a detailed inspection for cracking of the crease beam and adjacent intercostals, stringers, frames, and skin panels at the applicable initial and repetitive compliance times specified in Table 1 of paragraph 1.E., “Compliance,” of the service bulletin; except, where the service bulletin specifies an initial compliance time after the date on the service bulletin, this AD requires compliance within the specified compliance time after the effective date of this AD. Do all applicable related investigative and corrective actions before further flight if any cracking is found. Do all applicable actions in and in accordance with the Accomplishment Instructions of the service bulletin, except as provided by paragraphs (f)(1) and (f)(2) of this AD.

(1) Where the service bulletin specifies to contact the manufacturer for instructions on how to repair certain conditions, before further flight, repair those conditions using a method approved in accordance with paragraph (g) of this AD.

(2) Where the service bulletin specifies to report certain information to the manufacturer, this AD does not include that requirement.

Alternative Methods of Compliance (AMOCs)

(g)(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) 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. Start Printed Page 44935

(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, and the approval must specifically refer to this AD.

Start Signature

Issued in Renton, Washington, on July 27, 2006.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.

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[FR Doc. E6-12835 Filed 8-7-06; 8:45 am]

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