Airworthiness Directives; Boeing Model 727 Series Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) for certain Boeing Model 727 series airplanes. That AD currently requires repetitive detailed inspections to detect cracking, corrosion, and existing stop-drilled repairs of cracking in the upper chord of the rear spar of the wing, and repair if necessary. This proposed AD would require new repetitive inspections to detect cracks, corrosion, minor surface defects, and existing stop-drilled repairs of cracks in the upper and lower chords of the front and rear spars of the wing; and repair if necessary. This proposed AD is prompted by our determination that further rulemaking action is necessary to require additional actions specified in the referenced service bulletin. We are proposing this AD to prevent structural failure of the wing and fuel leaks in the airplane due to stress corrosion cracking of the wing spar chords.

DATES:

We must receive comments on this proposed AD by December 20, 2004.

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.

You can get the service information identified in this proposed AD from Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.

You may examine the contents of this AD docket on the Internet at http://dms.dot.gov,, or 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.

FOR FURTHER INFORMATION CONTACT:

Daniel F. Kutz, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 917-6456; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Docket Management System (DMS)

The FAA has implemented new procedures for maintaining AD dockets electronically. As of May 17, 2004, new AD actions are posted on DMS and assigned a docket number. We track each action and assign a corresponding directorate identifier. The DMS AD docket number is in the form “Docket No. FAA-2004-99999.” The Transport Airplane Directorate identifier is in the form “Directorate Identifier 2004-NM-999-AD.” Each DMS AD docket also lists the directorate identifier (“Old Docket Number”) as a cross-reference for searching purposes.

Comments Invited

We invite you to submit any written relevant data, views, or arguments regarding this proposed AD. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2004-19530; Directorate Identifier 2002-NM-274-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 our docket 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 the 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.

We are reviewing the writing style we currently use in regulatory documents. We are interested in your comments on whether the style of this document is clear, and your suggestions to improve the clarity of our communications that affect you. You can get more information about plain language at http://www.faa.gov/language and http://www.plainlanguage.gov.

Examining the Docket

You may examine the AD docket 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.

Discussion

On November 20, 2002, we issued AD 2002-24-05, amendment 39-12970 (67 FR 71808, December 3, 2002) (a final rule correction was published in the Federal Register on January 2, 2003 (68 FR 10)), for certain Boeing Model 727 series airplanes. That AD requires repetitive detailed inspections to detect cracking, corrosion, and existing stop-drilled repair of cracking in the upper chord of the rear spar of the wing, and repair if necessary. That AD was prompted by reports of spanwise stress corrosion cracking of the upper chord of the rear spar of the wing between wing buttock line (WBL) 70.5 and the wing tip. Investigation revealed that some cracks were up to 14 inches long. Furthermore, one of the cracks was almost long enough to jeopardize the residual strength capability of the upper chord of the rear spar. We issued that AD to prevent structural failure of the wing and fuel leaks in the airplane due to stress corrosion cracking of the wing spar chords.

Actions Since Existing AD Was Issued

In the preamble of AD 2002-24-05, we indicated that the actions required by that AD were considered “interim action,” and that further rulemaking action was being considered to require additional actions specified in the referenced service bulletin (i.e., Boeing Alert Service Bulletin 727-57A0145, Revision 2, dated October 24, 2002). We have now determined that further rulemaking action is indeed necessary, and this proposed AD follows from that determination.

Relevant Service Information

We have reviewed Boeing Alert Service Bulletin 727-57A0145, Revision 2, dated October 24, 2002. The service bulletin describes procedures for performing various inspections to detect cracks, corrosion, minor surface defects, and previously stop-drilled repairs in the upper and lower chords of the front and rear spars of the wings; and repair if necessary. The service bulletin also describes procedures for applying a wet layer of BMS 3-23 organic corrosion inhibiting compound or Boeing equivalent after any inspection or repair. We have determined that accomplishment of the actions specified in the service information will 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 products of this same type design. Therefore, we are proposing this AD, which would supersede AD 2002-24-05 to require accomplishment of all actions specified in the service bulletin described previously, except as described below.

Differences Between the Service Bulletin and the Proposed AD

Operators should note that, although the service bulletin specifies that the manufacturer may be contacted for disposition of certain repair conditions, this proposed AD would require that those conditions be done in accordance with a method approved by the FAA, or in accordance with data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative who has been authorized by the FAA to make such findings.

Clarification of Inspection Terminology

In this proposed AD, the “detailed visual inspection” specified in the Boeing service bulletin is referred to as a “detailed inspection.” We have included the definition for a detailed inspection in a note in the proposed AD.

Change to Existing AD

This proposed AD would retain certain requirements of AD 2002-24-05. Since that AD 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:

Costs of Compliance

This Proposed AD would affect about 1,426 Model 727 series airplanes worldwide. This Proposed AD would affect about 946 airplanes of U.S. registry.

For Group 1 airplanes identified in the service bulletin, the actions (Part 1 of the Accomplishment Instructions of the service bulletin) that are required by AD 2002-24-05 and retained in this Proposed AD take about 8 work hours per airplane, at an average labor rate of $65 per work hour. Based on these figures, the estimated cost of the currently required actions is $520 per airplane.

The following table provides the estimated costs for U.S. operators to comply with the new actions proposed by this AD. The average labor rate is $65 per work hour.

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. 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
• 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.