04-9591. Airworthiness Directives; Boeing Model 737-200C Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Final rule.

SUMMARY:

This amendment adopts a new airworthiness directive (AD), applicable to all Boeing Model 737-200C series airplanes, that requires repetitive inspections of the Station 348.2 frame to detect cracking under the stop fittings and intercostal flanges at Stringers 14L, 15L, and 16L; and corrective action if necessary. This action is necessary to prevent rapid decompression of the airplane, and possible separation of the forward entry door from the airplane. This action is intended to address the identified unsafe condition.

DATES:

Effective June 4, 2004.

The incorporation by reference of a certain publication listed in the regulations is approved by the Director of the Federal Register as of June 4, 2004.

ADDRESSES:

The service information referenced in this AD may be obtained from Boeing Commercial Airplanes, PO Box 3707, Seattle, Washington 98124-2207. This information may be examined at the Federal Aviation Administration (FAA), Transport Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT:

Howard Hall, 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:

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to all Boeing Model 737-200C series airplanes was published in the Federal Register on February 19, 2004 (69 FR 7706). That action proposed to require repetitive inspections of the Station 348.2 frame to detect cracking under the stop fittings and intercostal flanges at Stringers 14L, 15L, and 16L; and corrective action if necessary.

Comments

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were submitted in response to the proposal or the FAA's determination of the cost to the public.

Conclusion

The FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

Cost Impact

There are approximately 78 airplanes of the affected design in the worldwide fleet. The FAA estimates that 15 airplanes of U.S. registry will be affected by this AD, that it will take approximately 18 work hours per airplane to accomplish the required inspections, and that the average labor rate is $65 per work hour. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $17,550, or $1,170 per airplane, per inspection cycle.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this 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 adopted herein will 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 final rule does not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this action (1) is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under 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. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

Adoption of the Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends 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:

2004-09-09 Boeing: Amendment 39-13598. Docket 2003-NM-208-AD.

Applicability: All Model 737-200C series airplanes; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent rapid decompression of the airplane, and possible separation of the forward entry door from the airplane, accomplish the following:

Initial and Repetitive Inspections

(a) Except as provided by paragraph (b) of this AD: Prior to the accumulation of 46,000 total flight cycles, or within 2,250 flight cycles after the effective date of this AD, whichever occurs later, do detailed and eddy current inspections of the Station 348.2 frame for cracking under the stop fittings and intercostal flanges at Stringers 14L, 15L, and 16L by accomplishing paragraphs 3.A. and 3.B.1. through 3.B.7. of the Accomplishment Instructions of Boeing Alert Service Bulletin 737-53A1240, dated April 10, 2003. Do the actions per the service bulletin. Any applicable repair must be accomplished prior to further flight. Repeat the inspections thereafter at intervals not to exceed 4,500 flight cycles.

Note 1:

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.”

Corrective Action

(b) If any crack is found during any inspection required by this AD, and the bulletin specifies to contact Boeing for appropriate action: 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.

Alternative Methods of Compliance

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

Incorporation by Reference

(d) Unless otherwise specified in this AD, the actions shall be done in accordance with Boeing Alert Service Bulletin 737-53A1240, dated April 10, 2003. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Boeing Commercial Airplanes, PO Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

Effective Date

(e) This amendment becomes effective on June 4, 2004.

Issued in Renton, Washington, on April 20, 2004.

Ali Bahrami,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.