Skip to Content

Proposed Rule

Airworthiness Directives; Boeing Model 727 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 all Boeing Model 727 airplanes. This proposed AD would require a one-time inspection of the lower lobe frames of body section 43 to find open holes between stringers 17L and 17R; repetitive high frequency eddy current (HFEC) inspections for cracks of all open holes; and related investigative and corrective actions if necessary. The proposed AD also would include the optional terminating action of installing rivets in all open tooling holes and all unused lining holes, which would terminate a repetitive open-hole HFEC inspection once a hole is plugged with a rivet. This proposed AD is prompted by reports of cracks at open tooling holes in the lower lobe frames of body section 43. We are proposing this AD to detect and correct cracks in the frames, which could result in cracks in the skin panels and rapid decompression of the airplane.

DATES:

We must receive comments on this proposed AD by June 16, 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-2005-21085; the directorate identifier for this docket is 2004-NM-252-AD.

Start Further Info

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.

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-2005-21085; Directorate Identifier 2004-NM-252-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.

Discussion

We have received a report of cracks at open tooling holes in 20 lower lobe frames of body section 43 on Boeing Model 727 series airplanes. The cracks were found during fatigue tests, and initiated at open tooling holes in the frame webs between stringers 17L and 17R. The cracks were caused by cyclic pressurization and fatigue loading. This condition, if not corrected, could result in cracks in the frames, which could result in cracks in the skin panels and rapid decompression of the airplane.

Relevant Service Information

We have reviewed Boeing Alert Service Bulletin 727-53A0227, dated September 16, 2004. The service bulletin describes procedures for doing the following inspections: Start Printed Page 22619

  • A general visual inspection of the lower lobe frames of body section 43 to find open holes between stringers 17L and 17R.
  • High frequency eddy current (HFEC) inspections for cracks of all open tooling holes.

The service bulletin recommends that operators record the locations of all open holes for reference during modification. These open holes include open tooling holes and any lining holes between 0.156 and 0.166 inch in diameter that operators may find when removing the cargo compartment lining.

If any crack of an open hole is found during any inspection, the service bulletin describes procedures for corrective and related investigative actions. If the crack is less than 0.063 inch in length, the service bulletin describes procedures for drilling the hole to an oversize dimension, performing further HFEC inspections to determine when all cracks have been removed, and installing a rivet in the open hole. If the crack is 0.063 inch in length or greater, the service bulletin recommends repairing the crack according to a method approved by the FAA. The service bulletin notes that Chapter 51-40-3 or Chapter 53-10-4 of the Boeing 727 Structural Repair Manual (SRM) are acceptable methods approved by the FAA.

The service bulletin also describes, in “Part 2—Modification,” procedures for plugging all open tooling holes and all unused lining holes with rivets, which would end the need for the repetitive inspections for those plugged holes. This modification includes drilling the hole to an oversize dimension, performing further HFEC inspections of cracked holes to determine when all cracks have been removed, and installing a rivet in the open hole.

Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition.

Other Related Rulemaking

On September 5, 1990, we issued AD 90-20-14, amendment 39-6730 (55 FR 37864, October 23, 1990), applicable to certain Boeing Model 727 series airplanes, which requires repetitive visual inspections of the forward cargo compartment sidewall frames for cracks, and repair if necessary. The actions required by that AD are intended to detect and correct cracks in the forward cargo compartment sidewall frames. AD 90-20-14 does not affect the requirements of this AD. However, the inspections in Boeing Alert Service Bulletin 727-53A0227 are an alternative method of compliance (AMOC) for the detailed inspections required by paragraph A. of AD 90-20-14. Inspection thresholds and repeat intervals in AD 90-20-14 are not included in or affected by this AMOC.

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 bulletin described previously, except as discussed under “Difference Between the Proposed AD and the Service Bulletin.” This proposed AD also would provide for optional terminating action for the repetitive inspections.

The proposed AD would allow repetitive inspections to continue in lieu of the terminating action. In making this determination, we considered that long-term continued operational safety in this case will be adequately ensured by repetitive inspections to detect cracking before it represents a hazard to the airplane.

Difference Between the Proposed AD and the 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.

Costs of Compliance

There are about 1,038 airplanes of the affected design in the worldwide fleet. This proposed AD would affect about 616 airplanes of U.S. registry. The proposed inspection would take between 8 and 15 work hours per airplane per inspection cycle, depending on the configuration of the airplane. The average labor rate is $65 per work hour. Based on these figures, the estimated cost of the proposed AD for U.S. operators is between $320,320 and $600,600, or between $520 and $975 per airplane, per inspection cycle.

For operators that choose to do the optional terminating action of installing rivets in all open tooling holes and all unused lining holes, the actions would take between 13 and 23 work hours per airplane, depending on the configuration of the airplane. The average labor rate is $65 per work hour. Based on these figures, the estimated cost of the optional terminating action is between $845 and $1,495 per airplane.

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, Start Printed Page 22620the 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-2005-21085; Directorate Identifier 2004-NM-252-AD.

Comments Due Date

(a) The Federal Aviation Administration (FAA) must receive comments on this AD action by June 16, 2005.

Affected ADs

(b) Accomplishing the inspections in paragraph (g) of this AD is an alternative method of compliance (AMOC) for the inspections required by paragraph A. of AD 90-20-14, amendment 39-6730, if accomplished in accordance with the requirements of paragraph (j)(2) of this AD.

Applicability

(c) This AD applies to all Boeing Model 727 series airplanes, certificated in any category.

Unsafe Condition

(d) This AD was prompted by reports of cracks at open tooling holes in the lower lobe frames of body section 43. We are issuing this AD to detect and correct cracks in the frames, which could result in cracks in the skin panels and 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.

Service Bulletin Reference

(f) The term “service bulletin,” as used in this AD, means the Accomplishment Instructions of Boeing Alert Service Bulletin 727-53A0227, dated September 16, 2004.

Inspections

(g) Before the accumulation of 40,000 total flight cycles, or within 3,500 flight cycles after the effective date of this AD, whichever occurs later: Do a general visual inspection of the lower lobe frames to find open holes between stringer 17L and stringer 17R of body section 43; and do an HFEC inspection for cracks of all open holes, including lining holes. Repeat the inspections at intervals not to exceed 3,500 flight cycles until the optional terminating action in paragraph (i) of this AD is accomplished. Do all inspections in accordance with the service bulletin.

Corrective Action

(h) If any crack is found during any inspection required by paragraph (g) of this AD: Before further flight, do the applicable corrective action in paragraph (h)(1) or (h)(2) of this AD.

(1) If the crack is less than 0.063 inch in length, do the corrective action and related investigative action in Figure 6 of the service bulletin.

(2) If the crack is 0.063 inch in length or greater, 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. Chapters 51-40-3 and 53-10-4 of the Boeing 727 Structural Repair Manual (SRM) are approved methods. Except for these SRMs, for a repair method to be approved, the approval must specifically reference this AD.

Optional Terminating Action

(i) Installing rivets in all open tooling holes, and all unused lining holes, according to Part 2 of the Work Instructions of the service bulletin terminates the repetitive inspection requirements of paragraph (g) of this AD only for those holes plugged with rivets. Terminating action for the repetitive inspection requirements of paragraph (g) of this AD is not permitted for all lining holes without installed rivets.

AMOCs

(j)(1) The Manager, Seattle ACO, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

(2) The inspection methods specified in paragraph (g) of this AD are AMOCs to the inspection methods required by paragraph A. of AD 90-20-14, amendment 39-6730. Inspection thresholds and repetitive intervals are not included in or affected by this AMOC. All other provisions of AD 90-20-14 that are not specifically mentioned above remain fully applicable and must be met.

(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 a Boeing Company Authorized Representative who has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the approval must specifically refer to this AD.

Start Signature

Issued in Renton, Washington, on April 21, 2005.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.

End Signature End Part End Supplemental Information

[FR Doc. 05-8655 Filed 4-29-05; 8:45 am]

BILLING CODE 4910-13-P