04-14180. Airworthiness Directives; Boeing Model 727-100 and -100C Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 727-100 and -100C series airplanes. This proposal would require repetitive inspections of the frame inner chord, outer chord, and web of the forward and aft edge frames of the lower lobe forward cargo door (FCD) cutout, and corrective action, if necessary. This action is necessary to detect and correct fatigue cracking of the forward and aft edge frames of the lower lobe FCD cutout, which could result in the loss of the FCD and rapid decompression of the airplane. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by August 9, 2004.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2003-NM-238-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to [phone]. Comments may also be sent via the Internet using the following address: [e-mail]. Comments sent via fax or the Internet must contain “Docket No. 2003-NM-238-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 or 2000 or ASCII text.

The service information referenced in the proposed rule may be obtained from Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

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 [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this action may be changed in light of the comments received.

Submit comments using the following format:

• Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
• For each issue, state what specific change to the proposed AD is being requested.
• Include justification (e.g., reasons or data) for each request.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2003-NM-238-AD.” The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2003-NM-238-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The FAA has received reports indicating that fatigue cracks were found at the inner chord, outer chord, and web of the forward and aft edge frames of the lower lobe forward cargo door (FCD) cutout on Boeing Model 727-100 and -100C series airplanes. The airplanes on which the fatigue cracks were found had accumulated between 37,500 and 68,700 total flight cycles. The fatigue cracks were discovered during routine inspections and during inspections conducted as part of the Boeing 727 Supplemental Structural Inspection Document (SSID) program required by AD 98-11-03 R1, amendment 39-10983 (64 FR 989, January 7, 1999). The SSID program initially inspects Model 727-100 series airplanes at 55,000 flight cycles and Model 727-100C series airplanes at 46,000 flight cycles and, therefore, will not detect possible cracking at earlier flight cycles. Fatigue cracks, if not detected and corrected, could result in the loss of the FCD and rapid decompression of the airplane.

Explanation of Relevant Service Information

The FAA has previously reviewed and approved pages F.11.2, F.11.12, and F.11.22 of Boeing Document No. D6-48040-1, Volumes 1 and 2, “Supplemental Structural Inspection Document” (SSID), Revision H, dated June 1994, which specify procedures to perform a general visual inspection, a detailed inspection, and a high frequency eddy current inspection for cracks in areas A and B of Structural Significant Item (SSI) F-11B (the area affected by this unsafe condition). Accomplishment of the actions specified in pages F.11.2, F.11.12, and F.11.22 of SSID, Revision H, is intended to adequately address the identified unsafe condition.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require accomplishment of the actions described previously for pages F.11.2, F.11.12, and F.11.22 of SSID, Revision H.

Cost Impact

There are approximately 180 airplanes of the affected design in the worldwide fleet. The FAA estimates that 124 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 3 work hours per airplane to accomplish the proposed inspections, and that the average labor rate is $65 per work hour. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $24,180, or $195 per airplane, per inspection cycle.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this proposed AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.

Regulatory Impact

The regulations proposed herein 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. Therefore, it is determined that this proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this 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) if promulgated, 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. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend part 39 of the Federal Aviation Regulations (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.

§ 39.13

[Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

Boeing: Docket 2003-NM-238-AD.

Applicability: Boeing Model 727-100 and -100C series airplanes, line numbers 1 through 695 inclusive; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To detect and correct fatigue cracking of the forward and aft edge frames of the lower lobe forward cargo door (FCD) cutout, which could result in the loss of the FCD and rapid decompression of the airplane, accomplish the following:

Note 1:

This AD is related to AD 98-11-03 R1, amendment 39-10983 (64 FR 989, January 7, 1999) and affects Structural Significant Item (SSI) F-11B of the Boeing 727 Supplemental Structural Inspection Document (SSID) program.

Initial and Repetitive Inspections

(a) For airplanes on which the forward and aft edge frames of the lower lobe FCD cutout have not been inspected per AD 98-11-03 R1 as of the effective date of this AD: Prior to the accumulation of 24,000 total flight cycles, or within 3,000 flight cycles after the effective date of this AD, whichever occurs later, do the inspections specified in paragraph (c) of this AD.

(b) For airplanes on which the forward and aft edge frames of the lower lobe FCD cutout have been inspected per AD 98-11-03 R1 as of the effective date of this AD: Within the next scheduled inspection required by AD 98-11-03 R1, or within 3,000 flight cycles after the effective date of this AD, whichever occurs first, do the inspections specified in paragraph (c) of this AD.

(c) Perform the inspections in paragraphs (c)(1), (c)(2), and (c)(3) of this AD at the forward and aft edge frames (between stringers S-18 and S-26) of the lower lobe FCD cutout per SSI F-11B (i.e., pages F.11.2, F.11.12, and F.11.22), of Boeing Document No. D6-48040-1, Volumes 1 and 2, “SSID”, Revision H, dated June 1994. Repeat the inspections thereafter at intervals not to exceed 3,000 flight cycles.

(1) Perform a general visual inspection of the frame inner chord, outer chord, and web in area “A” for cracks.

Note 2:

For the purposes of this AD, a general visual inspection is defined as: “A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to enhance visual access to all exposed surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.”

(2) Perform a detailed inspection of the frame inner chord, outer chord, and web in area “B” for cracks.

Note 3:

For the purposes of this AD, a detailed inspection is defined as: “An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.”

(3) Perform a high frequency eddy current inspection of the frame inner and outer chords in area “B” where the frame web is not visible for cracks.

Corrective Action

(d) If any crack is found during any inspection required by paragraph (c) of this AD, before further flight, repair per a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or per data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative who has been authorized by the Manager, Seattle ACO, to make such findings. For a repair method to be approved, the approval must specifically reference this AD.

Certain Actions Constitute Compliance With AD 98-11-03 R1

(e) Accomplishment of the inspections specified in paragraph (c) of this AD is terminating action for the inspections required by AD 98-11-03 R1 that pertain to SSI F-11B of the Boeing 727 SSID program for the areas specified in paragraph (c) of this AD only. Accomplishment of the actions required by paragraph (c) of this AD does not terminate the inspections required by AD 98-11-03 R1 for the remaining areas of SSI F-11B and does not terminate the remaining requirements of AD 98-11-03 R1.

Alternative Methods of Compliance

(f) In accordance with 14 CFR 39.19, the Manager, Seattle ACO, FAA, is authorized to approve alternative methods of compliance for this AD.

Issued in Renton, Washington, on June 16, 2004.

Ali Bahrami,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.