AD 94-12-02

This amendment adopts a new airworthiness directive (AD), applicable to certain Saab Model SAAB SF340A and SAAB 340B series airplanes, that requires an inspection of the elevator and aileron coves, and further inspections and repair, if necessary. This amendment is prompted by a report of delamination between the composite structure and the aluminum foil on the elevator cove on a Model SAAB SF340B series airplane. The actions specified by this AD are intended to prevent jamming of the aileron or elevator.

Final rule

94-12-02 SAAB AIRCRAFT AB: Amendment 39-8929. Docket 93-NM-233-AD.
Applicability: Model SAAB SF340A series airplanes, serial numbers -004 through -159, inclusive; and Model SAAB 340B series airplanes, serial numbers -160 through -260, inclusive; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent jamming of the aileron or elevator, accomplish the following:

(a) Within 500 hours time-in-service or 90 days after the effective date of this AD, whichever occurs first, perform an inspection of the elevator and aileron coves to verify the type of antistatic protection applied to the coves, in accordance with Saab Service Bulletin 340-51-012, dated November 10, 1993.

(b) If a cove has conductive paint or expanded aluminum foil (stretched metal - aluminum net), no further action is required by this AD for that cove.

(c) If a cove does not have conductive paint or expanded aluminum foil (stretched metal -aluminum net), prior to further flight, perform a detailed visual inspection and delamination tap test to detect aluminum foil delamination on the elevator or aileron cove, in accordance with the Saab Service Bulletin 340-51-012, dated November 10, 1993.

(1) If no delamination is found, repeat the detailed visual inspection and delamination tap test thereafter at intervals not to exceed 800 hours time-in-service in accordance with the service bulletin.

(2) If any delamination is found, prior to further flight, accomplish either paragraph (c)(2)(i) or (c)(2(ii) of this AD.

(i) Perform a temporary repair of the cove in accordance with the service bulletin. Thereafter, repeat the detailed visual inspection and delamination tap test required by paragraph (c) of this AD at intervals not to exceed 800 hours time-in-service. Or

(ii) Perform a permanent repair of the cove in accordance with the service bulletin. Accomplishment of this permanent repair constitutesterminating action for the repetitive inspection required by this AD.

(d) 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, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Standardization Branch, ANM-113.

NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Standardization Branch, ANM-113.

(e) 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.

(f) The inspections and repairs shall be done in accordance with Saab Service Bulletin 340-51-012, dated November 10, 1993. 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, Linkoping, 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.

(g) This amendment becomes effective on July 13, 1994.

FOR FURTHER INFORMATION CONTACT: Mark Quam, Aerospace Engineer, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 227-2145; fax (206) 227-1320.

A proposal to amend part 39 of the Federal Aviation Regulations 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 February 4, 1994 (59 FR 5361). That action proposed to require an inspection of the elevator and aileron coves to verify the type of antistatic protection applied to the coves. For coves that are found without conductive paint or expanded aluminum foil, that action proposed to require a detailed visual inspection and delamination tap test to detect aluminum foil delamination on the coves; and either a temporary repair and repetitive detailed visual inspections and delamination tap tests of the coves, or a permanent repair of the coves. Accomplishment of the permanent repair terminates the repetitive detailed visual inspections and delamination tap tests.

Interested persons have been afforded an opportunity to participatein 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. The FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

The FAA estimates that 152 airplanes of U.S. registry will be affected by this AD, that it will take approximately 20 work hours per airplane to accomplish the inspection, and that the average labor rate is $55 per work hour. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $167,200, or $1,000 per airplane.

The total 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 regulations adopted herein will not have substantial direct effects 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, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

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 14 CFR part 39 of the Federal Aviation Regulations as follows:

PART 39 - AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89.

39.13 - [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: