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Proposed Rule

Airworthiness Directives; Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SR, 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.

Start Preamble

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 Start Printed Page 14590certain Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SR, and 747SP series airplanes. This proposed AD would require doing a one-time high-frequency eddy current inspection and repetitive detailed inspections for cracks in the frame web of main entry door number 1; and repairing the door frame web if necessary. This proposed AD would also provide for optional terminating action for the repetitive inspections. This proposed AD is prompted by reports of cracking at the upper aft corner of the cutout for main entry door number 1 in the station 488 frame web. We are proposing this AD to detect and correct cracks in the frame web. These cracks could cause the frame to break and lead to rapid decompression of the airplane.

DATES:

We must receive comments on this proposed AD by May 9, 2005.

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.

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-2005-20692; the directorate identifier for this docket is 2004-NM-229-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

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 under ADDRESSES. Include “Docket No. FAA-2005-20692; Directorate Identifier 2004-NM-229-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 website, 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.

Discussion

We have received reports indicating that operators have found several cracks in the station 488 frame web at the upper aft corner of the cutout for main entry door number 1 on at least three Boeing Model 747-200B series airplanes. Cracks were found in the web common to the door stop number 9 fastener holes on one of the airplanes, and at the tooling hole in the web above stringer 17 on two other airplanes. The manufacturer found similar cracks on a Model 747-100SR fatigue test airplane and determined the cracks were caused by fatigue due to cabin pressurization cyclic loading. This condition, if not detected and corrected in a timely manner, could cause the frame to break and lead to rapid decompression of the airplane.

Similar Models

The main entry door frame webs on certain Model 747-100, 747-100B, 747-100B SUD, 747-200C, 747-200F, 747-300, 747SR, and 747SP series airplanes are similar to those on the affected Model 747-200B series airplanes. Therefore, all of these models may be subject to the same unsafe condition.

Relevant Service Information

We have reviewed Boeing Alert Service Bulletin 747-53A2508, dated August 19, 2004. The service bulletin describes procedures for doing a one-time high-frequency eddy current (HFEC) inspection for cracks in the forward side of the station 488 door frame web at the tooling hole above stringer 17 and around door stop number 9; for doing repetitive detailed inspections for cracks in the forward side of the station 488 door frame web between door stop number 8 and the upper door sill; and for repairing the door frame web if necessary. Repairing the door frame web would eliminate the need for repetitive detailed 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. Therefore, we are proposing this AD, which would require accomplishing the actions specified in the service information described previously, except as discussed under “Difference Between the Proposed AD and Referenced Service Bulletin.”

Difference Between the Proposed AD and Referenced Service Bulletin

The service bulletin specifies that you may contact the manufacturer for instructions on how to repair certain conditions, but this proposed AD would require you to repair 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 Delegation Option Authorization Organization whom we have authorized to make those findings.Start Printed Page 14591

Clarification of References to Additional Service Information

Boeing Alert Service Bulletin 747-53A2508 also identifies Boeing Service Bulletin 747-53-2349 (cited in AD 2002-10-10, amendment 39-12756 (67 FR 36081, dated May 23, 2002)), and Boeing Alert Service Bulletin 747-53A2265 (cited in AD 91-11-01, amendment 39-6997 (56 FR 22306, dated May 15, 1991)), as alternative sources of information for accomplishing the repetitive detailed inspections specified in this proposed AD.

Boeing Alert Service Bulletin 747-53A2508 refers to Boeing Service Bulletin 747-53-2272 as an alternative for accomplishing the open-hole HFEC inspection of the frame inner chord specified in this proposed AD. If the frame inner chord replacement required by AD 91-11-01 (which refers to Service Bulletin 747-53-2272 as a source of service information) is being done concurrently with the repair of the door frame web at station 488 specified in this proposed AD, the open-hole HFEC inspection specified in this proposed AD is unnecessary.

Costs of Compliance

There are about 274 airplanes of the affected design in the worldwide fleet. This proposed AD would affect about 140 airplanes of U.S. registry. The following table, using an estimated labor rate of $65 per work hour, provides the estimated costs for U.S. operators to comply with this proposed AD.

Inspection Costs

AirplanesNumber of airplanesWork hoursCost per airplaneFleet cost
Group 1 (left and right side HFEC inspection)1192$130$15,470.
Group 1 (left and right side detailed inspection)1192$130, per inspection cycle$15,470, per inspection cycle.
Group 2 (left side HFEC inspection)161$65$4,400.
Group 2 (left side detailed inspection)161$65, per inspection cycle$4,400, per inspection cycle.
Group 3 (left and right side HFEC inspection)52$130$650.
Group 3 (left and right side detailed inspection)52$130, per inspection cycle$650, 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. See the ADDRESSES section for a location to examine the regulatory evaluation.

Start List of Subjects

List of Subjects in 14 CFR Part 39

End List of Subjects

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:

Start Authority

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

End Authority
[Amended]

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

Boeing: Docket No. FAA-2005-20692; Directorate Identifier 2004-NM-229-AD.

Comments Due Date

(a) The Federal Aviation Administration (FAA) must receive comments on this AD action by May 9, 2005.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SR, and 747SP series airplanes, certificated in any category; as identified in Boeing Alert Service Bulletin 747-53A2508, dated August 19, 2004.

Unsafe Condition

(d) This AD was prompted by reports of cracking at the upper aft corner of the cutout for main entry door number 1 in the station 488 frame web. We are issuing this AD to detect and correct cracks in the frame web. These cracks could cause the frame to break and lead to rapid decompression 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.

Initial Inspections

(f) Before the accumulation of 16,000 total flight cycles, or within 1,000 flight cycles after the effective date of this AD, whichever occurs later, do a high frequency eddy current (HFEC) inspection and a detailed inspection of the station 488 frame web, by doing all of the actions specified in the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2508, dated August Start Printed Page 1459219, 2004; except as provided by paragraph (h) or (j) of this AD.

Repetitive Inspections

(g) If no crack is found during the inspections required by paragraph (f) of this AD, repeat the detailed inspection required by paragraph (f) of this AD at the applicable time specified in paragraph (g)(1) or (g)(2) of this AD.

(1) For airplanes identified in the service bulletin as Groups 1 and 2: At intervals not to exceed 3,000 flight cycles.

(2) For airplanes identified in the service bulletin as Group 3: At intervals not to exceed 1,500 flight cycles.

Repairs

(h) If any crack in the main entry door frame web is found during any inspection required by this AD: Before further flight, repair in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-53A2508, dated August 19, 2004. Where the service bulletin specifies to contact Boeing for appropriate action: Before further flight, repair the door frame web and any frame chord damage according to a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or according to data meeting the type certification basis of the airplane approved by an Authorized Representative for the Boeing Delegation Option Authorization (DOA) Organization who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the approval must specifically reference this AD.

Termination of Repeat Inspections

(i) For the repaired frame web only, accomplishing the door frame web repair required by paragraph (h) of this AD ends the repetitive inspections required by paragraph (g) of this AD.

Credit for Accomplishing HFEC Inspection Using Alternate Service Information

(j) If the frame inner chord replacement required by AD 91-11-01 (which identifies Service Bulletin 747-53-2272 as a source of service information) is accomplished concurrently with the repair of the station 488 door frame web specified by paragraph (h) of this AD, the HFEC inspection required paragraph (f) of this AD is not required.

Alternative Methods of Compliance (AMOCs)

(k)(1) The Manager, Seattle 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) 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 DOA 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 March 14, 2005.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.

End Signature End Part End Supplemental Information

[FR Doc. 05-5696 Filed 3-22-05; 8:45 am]

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