01-29184. Airworthiness Directives; Saab Model SAAB SF340A and SAAB 340B Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Final rule.

SUMMARY:

This amendment adopts a new airworthiness directive (AD), applicable to certain Saab Model SAAB SF340A and SAAB 340B series airplanes, that requires a one-time review of records to determine whether an airplane has been repainted since its delivery from the factory; and a one-time inspection to detect damage associated with improper preparation for the repainting, and corrective action if necessary. This amendment is prompted by mandatory continuing airworthiness information from a foreign civil airworthiness authority. The actions specified by this AD are intended to detect and correct damage to the aluminum skin of the airplane, which could result in a weakening of the structure of the airplane.

DATES:

Effective December 31, 2001.

The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of December 31, 2001.

ADDRESSES:

The service information referenced in this AD may be obtained from Saab Aircraft AB, SAAB Aircraft Product Support, S-581.88, Linköping, Sweden. 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:

Todd Thompson, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 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 certain Saab Model SAAB SF340A and SAAB 340B series airplanes was published in the Federal Register on August 17, 2001 (66 FR 43130). That action proposed to require a one-time review of records to determine whether an airplane has been repainted since its delivery from the factory; and a one-time inspection to detect damage associated with improper preparation for the repainting, and corrective action if necessary.

Comments

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

Requests To Revise Compliance Time for Initial Actions

The compliance time of the proposed AD is 200 flight hours, which corresponds to the compliance time mandated by parallel Swedish airworthiness directive SAD 1-161 R1, dated March 5, 2001. Several commenters note that the parallel Swedish airworthiness directive has been further revised to correct a printing error. SAD 1-161 R2, dated March 13, 2001, was issued to revise the compliance time to 2,000 flight hours. The commenters request that the proposed AD be revised to reflect the longer compliance time. They assert that there is no correlation between 200 flight hours and 1 year, and that the average fleet utilization is approximately 2,000 flight hours annually or about 200 flight hours every 2 to 3 months.

The FAA concurs, for the reasons identified by the commenters. The compliance times for the initial actions specified by paragraphs (a) and (b) of the final rule have been revised accordingly.

Requests To Extend Compliance Time for Corrective Action

Paragraph (b)(2) of the proposed AD specifies that chemical stripping and corrective action must be accomplished prior to further flight after detection of discrepancies. Two commenters request that the proposed AD be revised to extend this compliance time to correspond to that specified in Saab Service Bulletin 340-51-020: 4,000 flight hours or 2 years. One commenter states that the proposed compliance time is far too restrictive, and requests that the airplane be allowed to continue in service for the period of time specified by the service bulletin. The commenter anticipates that requiring immediate repair might ground numerous airplanes and impose significant economic impact on Saab operators.

Based on the comments and the findings of the manufacturer and the Luftfartsverket (LFV), which is the airworthiness authority for Sweden, FAA agrees that allowing up to 4,000 flight hours or 2 years for those actions would not compromise the safety of affected airplanes. Such an interim period of flight with known discrepancies is acceptable in light of the safety implications, the average utilization rate of the affected fleet, the practical aspects of scheduling repair during regular maintenance periods, and the availability of required parts. Paragraph (b)(2) of this final rule has been revised accordingly.

Request To Allow Alternative Paint

One commenter requests that the proposed AD be revised to allow use of an alternative paint system that would extend the compliance time temporarily until final corrective action, if necessary, can be accomplished. The commenter asserts that other paint systems commonly used in the industry, if appropriately applied, would provide adequate protection for another two years if no corrosion is found.

The FAA does not concur with the request. Developing an exhaustive list of all possible paint systems that would be acceptable for compliance with this AD would be very difficult. However, under the provisions of paragraph (c) of the final rule, the FAA may approve requests to use an alternative paint system if data are submitted to substantiate that such an alternative paint system would provide an acceptable level of safety.

Request To Allow Manufacturer Approval of Corrective Action

The proposed AD specifies that the FAA or the LFV (or its delegated agent) must approve methods of corrective action if pitting corrosion or reduced skin thickness is detected. One commenter requests that the proposed AD be revised to specify that the manufacturer, rather than the FAA or the LFV, approve the repair methods. The commenter asserts that repair approval by the manufacturer would omit unnecessary approval actions by the FAA or the LFV. The commenter adds that the FAA has always accepted manufacturer's data, and that this policy of manufacturer involvement should continue in this case to avoid inappropriate repairs.

The FAA does not concur with the request to allow manufacturer approval of repair methods, which would constitute delegating the FAA's rulemaking authority to the manufacturer. However, as the proposed AD stated, the approval may be obtained from either the FAA or the LFV (or the LFV's designated agent). The LFV's designated agent is often a representative of the manufacturer. In any event, the manufacturer is consulted on issues related to appropriate repair methods so that the approved repair scheme will be consistent with methods previously used on a particular airplane. No change to the final rule is necessary in this regard.

Requests for Definition of “Approved” Paint System

Two commenters request that paragraph (b) of the proposed AD be revised to clearly define an “approved” paint system. One of the commenters notes that the proposed AD does not account for previous paint systems applied on the airplane. That commenter requests that the AD provide specifications that will enable operators to distinguish approved from unapproved paint systems to avoid confusion. The other commenter questions whether a paint system is “approved” by the manufacturer or by virtue of being performed at a paint facility using an FAA-approved paint system.

The FAA agrees that clarification may be necessary. The SAAB 340 paint system is approved by the LFV as part of the type design. The FAA accepts the LFV approval and considers the paint system to be FAA-approved. Criteria for an approved paint system are found in section 51-20-43 of the Saab 340 Structural Repair Manual, as referred to by Saab Service Bulletin 340-51-020, Revision 01, dated May 16, 2001. Paragraph (b)(2)(ii)(B) of this AD has been revised to include this definition.

Additional Change to Final Rule

The FAA notes that paragraph (b)(2)(ii)(B)(2) of the proposed AD inadvertently referred to airplanes that were “painted,” instead of “repainted,” using an unapproved paint system. This final rule has been revised accordingly.

Conclusion

After careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule with the changes described previously. The FAA has determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

Cost Impact

The FAA estimates that 288 airplanes of U.S. registry will be affected by this AD.

It will take 1 work hour per airplane to review the records, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the records review on U.S. operators is estimated to be $17,280, or $60 per airplane.

For those airplanes that have been repainted, it will take 20 to 45 work hours per airplane to accomplish the inspection, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the inspection is estimated to be $1,200 to $2,700 per airplane.

The cost impact figures discussed above are 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:

2001-23-12 Saab Aircraft AB: Amendment 39-12511. Docket 2001-NM-91-AD.

Applicability: Model SAAB SF340A series airplanes having serial numbers -004 through -159 inclusive, and SAAB 340B series airplanes having serial numbers -160 through -459 inclusive; certificated in any category.

Note 1:

This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To detect and correct damage to the aluminum skin of the airplane, which could result in a weakening of the structure of the airplane, accomplish the following:

Review of Records

(a) Within 2,000 flight hours or 1 year after the effective date of this AD, whichever occurs first: Perform a review of records to determine whether an airplane subject to this AD has been repainted since its delivery from the factory. If the airplane has not been repainted, no further action is needed.

Inspection and Corrective Action

(b) If an airplane has been repainted since its delivery from the factory: Within 2,000 flight hours or 1 year after the effective date of this AD, whichever occurs first, perform chemical stripping of local areas of the skin and inspection to detect damage to (or removal of) the protective coat of bonding primer, in accordance with Saab Service Bulletin 340-51-020, Revision 01, dated May 16, 2001.

(1) If no damage to the protective coat of bonding primer is detected: Prior to further flight, repaint the stripped areas, in accordance with the service bulletin.

(2) If damage to (or removal of) the protective coat of bonding primer is detected: Prior to further flight, repaint the stripped areas, in accordance with the service bulletin; and within 4,000 flight hours or 2 years after detection of the damage or removed protective coating, perform additional chemical stripping and inspection of the skin for pitting corrosion, in accordance with the service bulletin.

(i) If pitting corrosion is detected: Perform corrective action in a manner and within a compliance time approved by the Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA, or the Luftfartsverket (or its designated agent).

(ii) If no pitting corrosion is detected: Prior to further flight, measure the thickness of the skin of the airplane, in accordance with the service bulletin.

(A) If a reduction in skin thickness is detected: Perform corrective action in a manner and within a compliance time approved by the Manager, International Branch, ANM-116, or the Luftfartsverket (or its designated agent).

(B) If no reduction in skin thickness is detected: Prior to further flight, check records to determine whether the airplane was repainted using an approved paint system. For purposes of this AD, criteria for an “approved” paint system are found in section 51-20-43 of the Saab 340 Structural Repair Manual.

(1) If the airplane was repainted using an approved paint system: Prior to further flight, repaint the stripped areas of the airplane, in accordance with the service bulletin.

(2) If the airplane was repainted using an unapproved paint system: Prior to further flight, chemically strip the entire airplane and repaint it, in accordance with the service bulletin.

Alternative Methods of Compliance

(c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, International Branch, ANM-116. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, International Branch, ANM-116.

Note 2:

Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116.

Special Flight Permits

(d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

Incorporation by Reference

(e) Except as required by paragraphs (a), (b)(2)(i), (b)(2)(ii)(A), and (b)(2)(ii)(B) of this AD: The actions shall be done in accordance with Saab Service Bulletin 340-51-020, Revision 01, dated May 16, 2001. 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, Linköping, Sweden. 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.

Note 3:

The subject of this AD is addressed in Swedish airworthiness directive SAD 1-161R2, dated March 13, 2001.

Effective Date

(f) This amendment becomes effective on December 31, 2001.

Issued in Renton, Washington, on November 15, 2001.

Kalene C. Yanamura,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.