AD 95-11-04 ACTIVE

This amendment adopts a new airworthiness directive (AD), applicable to certain Aerospatiale Model ATR42-200, -300, and -320 series airplanes, that requires modification of the wiring in the elevator controls and the pitch trim dissymmetry monitoring equipment. This amendment is prompted by a report of loss of a propeller and engine gearbox, which resulted in damage to the fuselage. There has also been a report that a modification was implemented in the elevator control cables during manufacture, which reduced the maximum physical separation between the elevator controls and the monitoring equipment. The actions specified by this AD are intended to prevent reduced controllability of the airplane in the event that debris from an engine burst or propeller failure were to strike the fuselage and sever the elevator flight controls.

Final rule.

95-11-04 AEROSPATIALE: Amendment 39-9238. Docket 94-NM-48-AD.

Applicability: Model ATR42-200, -300, and -320 series airplanes, as listed in Aerospatiale Service Bulletins ATR42-27-0068 and ATR42-27-0069, both dated January 25, 1994; 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 use the authority provided in paragraph (b) to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition; or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any airplane from the applicability of this AD.

Compliance: Required as indicated, unless accomplished previously.

To prevent reduced controllability of the airplane, accomplish the following:

(a) Within 12 months after the effective date of this AD, modify the wiring in the elevator controls and the pitch trim dissymmetry monitoring equipment, in accordance with Aerospatiale Service Bulletin ATR42-27-0068 or ATR42-27-0069, both dated January 25, 1994; as applicable.

(b) 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 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Standardization Branch, ANM-113.

(c) 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.

(d) The modification shall be done in accordance with Aerospatiale Service Bulletin ATR42-27-0068, dated January 25, 1994; or Aerospatiale Service Bulletin ATR42-27-0069, dated January 25, 1994; as applicable. 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 Aerospatiale, 316 Route de Bayonee, 31060 Toulouse, Cedex 03, France. 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.

(e) This amendment becomes effective on June 23, 1995.

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 Aerospatiale Model ATR42-200, -300, -320 series airplanes was published in the Federal Register on July 20, 1994 (59 FR 36998). That action proposed to require modification of the wiring in the elevator controls and the pitch trim dissymmetry monitoring equipment.

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

The manufacturer requests that reference to a certain incident involving a Model ATR42-300 series airplane be deleted from the Discussion section of the preamble of the proposed rule. The manufacturer states that the incident did not result in any damage to flight controls and, therefore, should not be referred to in the final rule. The FAA acknowledges that, since the incidentwas apparently not connected with the flight controls, deletion of the reference to the incident would be appropriate. However, since the Discussion section of the preamble of the proposal does not reappear in the final rule, no change to the final rule is necessary.

Another commenter requests that the compliance time to perform the modification be extended from the proposed 3 months to 12 months. The commenter states that investigation has shown that only 4% of all affected operators have found any defective propellers. The commenter states that detection of this small percentage of defective propellers does not justify the urgency of a 3-month compliance time. The FAA concurs with the commenter's request to extend the compliance time for the modification requirements. The FAA's intent was that the modifications be performed during a regularly scheduled maintenance visit for the majority of the affected fleet, when the airplanes would be located at a base where special equipment and trained personnel would be readily available, if necessary. Based on the information supplied by the commenter, the FAA now recognizes that 12 months corresponds more closely to the interval representative of most of the affected operators' normal maintenance schedules. Paragraph (a) of the final rule has been revised to reflect a compliance time of 12 months. The FAA does not consider that this extension will adversely affect safety.

As a result of recent communications with the Air Transport Association (ATA) of America, the FAA has learned that, in general, some operators may misunderstand the legal effect of AD's on airplanes that are identified in the applicability provision of the AD, but that have been altered or repaired in the area addressed by the AD. The FAA points out that all airplanes identified in the applicability provision of an AD are legally subject to the AD. If an airplane has been altered or repaired in the affected area in such a way as to affect compliance with the AD, the owner or operator is required to obtain FAA approval for an alternative method of compliance with the AD, in accordance with the paragraph of each AD that provides for such approvals. A note has been added to this final rule to clarify this long-standing requirement.

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 these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

The FAA has recently reviewed the figures it has used over the past several years in calculating the economic impact of AD activity. In order to account for various inflationary costs in the airline industry, the FAA has determined that it is necessary to increase the labor rate used in these calculations from $55 per work hour to $60 per work hour. The economic impact information, below, has been revised to reflect this increase in the specified hourly labor rate.

The FAA estimates that 110 airplanes of U.S. registry will be affected by this AD, that it will take approximately 49 work hours per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. Required parts will be provided by the manufacturer at no cost to operators. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $323,400, or $2,940 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 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. 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:

The service information referenced in this AD may be obtained from Aerospatiale, 316 Route de Bayonee, 31060 Toulouse, Cedex 03, France. 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.

Sam Grober, Aerospace Engineer, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 227-1187; fax (206) 227-1320.