AD 95-03-07

This amendment adopts a new airworthiness directive (AD), applicable to certain Aerospatiale Model ATR72 series airplanes, that requires an inspection to determine the model and orientation of certain flight control rods, and replacement of the rods with modified rods, if necessary. This amendment is prompted by reports of corrosion found on the pitch and rudder trim and rudder travel limiter fail-safe rods. The actions specified by this AD are intended to prevent problems associated with corrosion of the flight control rods, which could compromise the required strength of these items.

Final rule.

95-03-07 AEROSPATIALE: Amendment 39-9144. Docket 94-NM-83-AD.

Applicability: Model ATR72-101, -102, -201, and -202 series airplanes; as listed in Aerospatiale Service Bulletin ATR72-27-1033, dated February 23, 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 (d) 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 problems associated with corrosion of the flight control rods, which could compromise the required strength of these items, accomplish the following:

NOTE 2: Rods replaced and installed in accordance with the instructions of any version of Aerospatiale Service Bulletin ATR72-27-1010 prior to the effective date of this AD are not affected by the requirements of this AD.

(a) For airplanes having Manufacturer's Serial Numbers (MSN) 126 through 183, inclusive: Within 18 months after the effective date of this AD, visually inspect the elevator trim fail-safe rods to determine the model and the orientation of the open end of the rod, in accordance with Part A of Aerospatiale Service Bulletin ATR72-27-1033, dated February 23, 1994.(1) If a SARMA-type rod is installed, prior to further flight, replace that rod with a modified rod, in accordance with Aerospatiale Service Bulletin ATR72-27-1012, Revision 3, dated October 7, 1991.

(2) If a TAC-type rod is installed, and if the open end of the rod is oriented in any direction other than downwards, prior to further flight, accomplish the reverse installation procedures specified in Aerospatiale Service Bulletin ATR72-27-1010, Revision 4, dated February 23, 1994.

(b) For airplanes having MSN's 126 through 198 inclusive, 204, and 207: Within 18 months after the effective date of this AD, visually inspect the rudder trim fail-safe rods to determine the model and the orientation of the open end of the rod, in accordance with Part B of Aerospatiale Service Bulletin ATR72-27-1033, dated February 23, 1994.

(1) If a SARMA-type rod is installed, prior to further flight, replace that rod with a modified rod, in accordance with Aerospatiale Service Bulletin ATR72-27-1012, Revision 3, dated October 7, 1991.

(2) If a TAC-type rod is installed, and if the open end of the rod is oriented in any direction other than downwards, prior to further flight, accomplish the reverse installation procedures specified in Aerospatiale Service Bulletin ATR72-27-1010, Revision 4, dated February 23, 1994.

(c) For airplanes having MSN's 198, and 126 through 237 inclusive: Within 18 months after the effective date of this AD, visually inspect the rudder travel limitation unit fail-safe rods to determine the model and the orientation of the open end of the rod, in accordance with Part C of Aerospatiale Service Bulletin ATR72-27-1033, dated February 23, 1994.

(1) If a SARMA-type rod is installed, prior to further flight, replace that rod with a new rod in accordance with Aerospatiale Service Bulletin ATR72-27-1027, dated July 28, 1993.

(2) If a TAC-type rod is installed at the rudder travel limitation rod location, and if the open end of the rod is oriented in any direction other than downwards, prior to further flight, inspect that rod in accordance with Aerospatiale Service Bulletin ATR72-27-1027, dated July 28, 1993.

(i) If no crack(s), deformation, or corrosion of the rod is found, prior to further flight, reinstall the rod so that the open end is oriented downwards, in accordance with the service bulletin.

(ii) If any crack(s), deformation, or corrosion of the rod is found, prior to further flight, replace the rod with a modified rod in accordance with the service bulletin.

(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 3: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, replacements, reverse installations, and reinstallation shall be done in accordance with the following Aerospatiale service bulletins, as applicable, which contain the specified effective pages:

Service Bulletin
Referenced and Date

Page Number
Revision Level
Shown on Page
Date
Shown on Page
ATR72-27-1012,
Revision 3,
October 7, 1991
1
2, 4, 6, 9
5, 7, 8
3
3
Original
1
2
October 7, 1991
October 29, 1990
November 21, 1990
May 16, 1991
ATR72-27-1033,
Original Issue,
February 23, 1994
1-10
Original
February 23, 1994
ATR72-27-1027,
Original Issue,
July 28, 1993
1-11
Original
July 28, 1993
ATR72-27-1010
Revision 4,
February 23, 1994
1, 3
2, 7
4
5, 6
4
Original
2
1
February 23, 1994
June 22, 1990
January 10, 1991
November 21, 1990

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 Bayonne, 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.

(g) This amendment becomes effective on March 30, 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 ATR72 series airplanes was published in the Federal Register on July 27, 1994 (59 FR 38139). That action proposed to require an inspection to determine the model and orientation of certain flight control rods, and replacement of the rods with modified rods, if necessary.

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. The FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

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 effects 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 requirement. The FAA has determined that this addition will neither increase the economic burden on any operator nor increase the scope of the AD.

Additionally, 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, theFAA 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 28 airplanes of U.S. registry will be affected by this AD, that it will take approximately 6 work hours per airplane to accomplish the required inspection, and that the average labor rate is $60 per work hour. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $10,080, or $360 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.

Should replacement of any of the flight control rods be necessary, the number of work hours and the cost of required parts will vary according to the type of replacement accomplished. In a "worst case scenario" (all subject rods needing replacement), the cost of parts will be approximately $8,200 per airplane. Labor necessary to accomplish replacement of a rod(s) will vary from 2 work hours to 10 work hours, at an average labor rate of $60 per work hour.

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 thefollowing new airworthiness directive: