AD 97-05-02

This amendment adopts a new airworthiness directive (AD), applicable to certain EMBRAER Model EMB-120 series airplanes, that requires removal of the upper channel fairings and their shims; and rework of the riveting holes, the aileron sealing canvas (aerodynamic seals), and the protective covers of the trim tab hinge fittings of the aileron and elevator. This amendment is prompted by reports of binding of the aileron due to water freezing between the upper channel fairings and the surface of the leading edge of the aileron. The actions specified by this AD are intended to prevent water from freezing these areas, which could result in binding of the aileron and subsequent reduced controllability of the airplane.

Final rule

97-05-02 EMBRAER: Amendment 39-9946. Docket 95-NM-51-AD.
Applicability: Model EMB-120 series airplanes; as listed in EMBRAER Service Bulletin No. 120-57-0021, Change 2, dated March 8, 1996; certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise 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 prevent binding of the aileron and subsequent reduced controllability of the airplane, accomplish the following:

(a) Within 3,000 hours time-in-service after the effective date of this AD, remove the upper channel fairings and their shims; and rework the riveting holes, the aileron sealing canvas (aerodynamic seals), and the protective covers of the trim tab hinge fittings of the aileron and elevator; in accordance with EMBRAER Service Bulletin No. 120-57-0021, Change 1, dated September 10, 1993; or Change 2, dated March 8, 1996.

(b) As of the effective date of this AD, no person shall install any aileron sealing canvas having part number (P/N) 120-08130-001, 120-08131-001, or 120-08132-001, on any airplane unless that canvas has been reworked in accordance with EMBRAER Service Bulletin No. 120-57-0021, Change 1, dated September 10, 1993; or Change 2, dated March 8, 1996.

(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, Atlanta Aircraft Certification Office (ACO), FAA, Small 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, Atlanta ACO.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Atlanta ACO.

(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.

(e) The actions shall be done in accordance with EMBRAER Service Bulletin No. 120-57-0021, Change 1, dated September 10, 1993; or EMBRAER Service Bulletin No. 120-57-0021, Change 2, dated March 8, 1996. This incorporation byreference 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 Embraer, Empresa Brasileira De Aeronautica S/A, Sao Jose Dos Campos, Brazil. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Atlanta Aircraft Certification Office, Small Airplane Directorate, Campus Building, 1701 Columbia Avenue, Suite 2-160, College Park, Georgia; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(f) This amendment becomes effective on April 2, 1997.

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 EMBRAER Model EMB-120 series airplanes was published in the Federal Register on May 22, 1995 (60 FR 27056). That action proposed to require removal of the upper channel fairings and their shims; and rework of the riveting holes, the aileron sealing canvas (aerodynamic seals), and the protective covers of the trim tab hinge fittings of the aileron and elevator.

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

Request to Reference Additional Service Information
The only commenter, a U.S. operator, supports the proposal, but requests that it be revised to reference EMBRAER Service Bulletin 120-57-0021, Change 2, dated March 8, 1996, as an appropriate source of service information. This change to the service bulletin revises Change 1, which was referenced in the proposal, by including additional rework instructions and correcting a reference to the Structural Repair Manual.

The FAA concurs. The FAA finds that accomplishment of the actions in accordance with either Change 1 or Change 2 of the EMBRAER service bulletin will provide an acceptable level of safety and meet the intent of this AD action. The final rule has been revised to reference both service documents. Operators who already have accomplished the actions in accordance with Change 1 will not have to perform any additional work.

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 change previously described. The FAA has determined that this change will neither increase the economic burden on any operator nor increase the scope of the AD.

Cost Impact
TheFAA estimates that 263 airplanes of U.S. registry will be affected by this AD, that it will take approximately 10 work hours per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. The cost for required parts is expected to be negligible. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $157,800, or $600 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.

Regulatory Impact
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 thisfinal 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 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: