AD 2004-24-06

This amendment adopts a new airworthiness directive (AD), applicable to certain Saab Model SAAB SF340A and SAAB 340B series airplanes. This AD requires replacement of the retract actuator bracket attachment bolt (RABAB) of the main landing gear (MLG) with a new RABAB; reidentification of the MLG shock strut; an inspection for corrosion, fretting, or other damage of certain RABABs; and applicable corrective actions. The actions specified by this AD are intended to prevent failure of the RABAB, which could result in loosening of the actuator bracket and consequent failure of the MLG to retract, with considerable damage to other landing gear parts, including the MLG trunnion fitting. This action is intended to address the identified unsafe condition.

Final rule.

2004-24-06 SAAB AIRCRAFT AB: Amendment 39-13882. Docket 2002-NM- 182-AD.

Applicability

Model SAAB SF340A series airplanes, serial numbers (S/Ns) 004 through 159 inclusive; and Model SAAB 340B series airplanes, S/Ns 160 through 459 inclusive; certificated in any category.

Compliance

Required as indicated, unless accomplished previously.

To prevent failure of the retract actuator bracket attachment bolt (RABAB), which could result in loosening of the retract actuator bracket and consequent failure of the main landing gear (MLG) to retract, with considerable damage to other landing gear parts, including the MLG trunnion fitting, accomplish the following:

Replacement/Reidentification of RABAB

(a) For airplanes not previously modified in accordance with Saab Service Bulletin 340-32-124, Revision 01, dated May 21, 2002: Within 12 months after the effective date of this AD, perform the actions specified in paragraphs (a)(1) and (a)(2) of this AD in accordancewith the Accomplishment Instructions of Saab Service Bulletin 340-32-131, dated June 29, 2004, including Attachments 1 and 2, both dated January 2002, and Attachments 3 and 4, both dated April 2002.

Note 1: APPH Ltd. Service Bulletins AIR83022-32-28 and AIR83064- 32-08, both dated January 2002, comprising Attachments 1 and 2; and Service Bulletins AIR83022-32-29 and AIR83064-32-09, both dated April 2002, comprising Attachments 3 and 4; are incorporated into Saab Service Bulletin 340-32-131 as additional sources of service information.

(1) Replace the existing RABAB with a new RABAB.

(2) Re-identify the MLG shock strut.

Inspection of RABAB

(b) For airplanes previously modified in accordance with Saab Service Bulletin 340-32-124, Revision 01, dated May 21, 2002: Within 6 months after the effective date of this AD, perform a one-time detailed inspection for corrosion, fretting, or other damage of any RABAB replaced in accordance with Saab Service Bulletin 340-32-124, Revision 01; and applicable corrective actions; in accordance with the Accomplishment Instructions of Saab Service Bulletin 340-32-131, dated June 29, 2004, including Attachments 1 and 2, both dated January 2002, and Attachments 3 and 4, both dated April 2002.

Note 2: For the purposes of this AD, a detailed inspection is "an intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirrors magnifying lenses, etc. may be necessary. Surface cleaning and elaborate procedures may be required."

Parts Installation

(c) As of the effective date of this AD, no person may install a MLG shock strut, part number (P/N) AIR83022-5 through -18 inclusive, or P/N AIR83064-1 through -5 inclusive, on any airplane; and no person may install a RABAB, P/N AIR124792, on any MLG shock strut.

Special Flight Permits

(d) Special flight permits are not allowed as specified in section 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199).

Alternative Methods of Compliance

(e) In accordance with 14 CFR 39.19, the Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA, is authorized to approve alternative methods of compliance for this AD.

Incorporation by Reference

(f) The actions shall be done in accordance with Saab Service Bulletin 340-32-131, dated June 29, 2004; including Attachments 1 and 2, both dated January 2002, and Attachments 3 and 4, both dated April 2002. 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 Saab Aircraft AB, SAAB Aircraft Product Support, S-581.88, Link[ouml]ping, Sweden. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call (202) 741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html .

Note 3: The subject of this AD is addressed in Swedish airworthiness directive 1-195, effective July 6, 2004.

Effective Date

(g) This amendment becomes effective on January 4, 2005.

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 certain Saab Model SAAB SF340A and SAAB 340B series airplanes was published as a supplemental notice of proposed rulemaking (NPRM) in the Federal Register on September 28, 2004 (69 FR 57892). That action proposed to require replacement of the retract actuator bracket attachment bolt (RABAB) of the main landing gear (MLG) with a new RABAB; reidentification of the MLG shock strut; an inspection for corrosion, fretting, or other damage of any RABAB; and applicable corrective actions.

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

We estimate that approximately 281 airplanes of U.S. registry will be affected by this AD, that it will take approximately 7 work hours per airplane to accomplish the required actions, and that the average labor rate is $65 per work hour. Required parts will be supplied at no cost by the manufacturer. Based on these figures, the cost impact of this AD on U.S. operators is estimated to be $127,855, or $455 per airplane.

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 atthe 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: