Airworthiness directives: Aerospatiale,

[Federal Register: September 10, 1999 (Volume 64, Number 175)]

[Proposed Rules]

[Page 49113-49115]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr10se99-33]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-365-AD]

RIN 2120-AA64

Airworthiness Directives; Aerospatiale Model SN-601 (Corvette) Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

SUMMARY: This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all Aerospatiale Model SN-601 (Corvette) series airplanes. This proposal would require repetitive inspections, and repair if necessary, of the locking indication system of the drag strut jack on the main landing gear (MLG) to detect corrosion and damage resulting from its operation. This proposal would also require replacement of seals and backup rings with new parts. This proposal is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by the proposed AD are intended to prevent failure of the locking indication system of the drag strut jack on the MLG due to corrosion. Such corrosion could prevent the MLG from locking and result in the subsequent collapse of the MLG.

DATES: Comments must be received by October 12, 1999.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-NM-365-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal holidays.

The service information referenced in the proposed rule may be obtained from Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 03, France. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2110; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this notice may be changed in light of the comments received.

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Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filedin the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: ``Comments to Docket Number 98-NM-365-AD.'' The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-NM-365-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The Direction Generale de l'Aviation Civile (DGAC), which is the airworthiness authority for France, notified the FAA that an unsafe condition may exist on all Aerospatiale Model SN-601 (Corvette) series airplanes. The DGAC advises that one occurrence of corrosion has been reported in the locking indication system of the drag strut jack on the main landing gear (MLG). Such corrosion could cause failure of the locking indication system of the drag strut jack, which could prevent the MLG from locking and result in the subsequent collapse of the MLG.

Explanation of Relevant Service Information

Messier-Dowty, the manufacturer of the affected MLG, has issued Technical Instruction No. 20403, Issue 2, dated March 1998, which describes procedures for repetitive inspections to detect corrosion and other damage, and repair if necessary, of the locking indication system of the drag strut jack on the MLG. The Technical Instruction also describes procedures for verification of the free displacement of the plungers, replacement of damaged parts with new parts, and replacement of all seals and back up rings with new parts. Accomplishment of the actions specified in the technical instruction is intended to adequately address the identified unsafe condition. The DGAC classified this technical instruction as mandatory and issued French airworthiness directive 98-179-021(B), dated May 6, 1998, in order to assure the continued airworthiness of these airplanes in France.

FAA's Conclusions

This airplane model is manufactured in France and is type certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the DGAC has kept the FAA informed of the situation described above. The FAA has examined the findings of the DGAC, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other airplanes of the same type design registered in the United States, the proposed AD would require accomplishment of the actions specified in the technical instruction described previously.

Cost Impact

The FAA estimates that 2 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 8 work hours per airplane to accomplish the proposed inspection, and that the average labor rate is $60 per work hour. The cost of required parts would be minimal. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $960, or $480 per airplane, per inspection cycle.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed 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 proposed herein would 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 proposal would not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

For the reasons discussed above, I certify that this proposed regulation (1) is not a ``significant regulatory action'' under Executive Order 12866; (2) is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, 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 copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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.

   Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

   Aerospatiale: Docket 98-NM-365-AD.

   Applicability: All Model SN-601 (Corvette) series airplanes, 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 (b) 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 failure of the locking indication system of the drag strut jack on the main landing gear (MLG) due to corrosion that could prevent the MLG from locking and result in the subsequent collapse of the MLG, accomplish the following:

   (a) Within 3,600 flight hours or 36 months after the effective date of this AD, whichever

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   occurs first, perform a detailed visual inspection to detect certain discrepancies of the locking indication system on the drag strut jack on the MLG, in accordance with Messier-Dowty Technical Instruction No. 20403, Issue 2, dated March 1998. Prior to reassembling the parts, replace all the seals and backup rings with new parts, in accordance with the Technical Instruction.

   (1) If no corrosion is found on either plunger, prior to further flight, inspect for the free displacement of both plungers, in accordance with the Technical Instruction.

   (i) If the displacement of both plungers is free without any hard points, repeat the inspection required by paragraph (a) of this AD thereafter at intervals not to exceed 72 months.

   (ii) If the displacement of either plunger is not free, prior to further flight, replace the plunger with a new plunger, in accordance with the Technical Instruction. Repeat the inspection required by paragraph (a) of this AD thereafter at intervals not to exceed 72 months.

   (2) If corrosion is found on either plunger, prior to further flight, replace the plunger with a new plunger, in accordance with the Technical Instruction. Repeat the inspection thereafter at intervals not to exceed 72 months.

   (3) If no corrosion, marking, binding, or peening is found on any disassembled part removed from the stacking, other than the plungers, repeat the inspection thereafter at intervals not to exceed 72 months.

   (4) If any corrosion, marking, binding or peening is found on any disassembled parts removed from the stacking, other than the plungers, prior to further flight, replace the part with a new part, in accordance with the Technical Instruction. Repeat the inspection thereafter at intervals not to exceed 72 months.

   Note 2: For the purposes of this AD, a detailed visual inspection is defined as: ``An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.''

   Alternative Methods of Compliance

   (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, International Branch, ANM-116, 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, International Branch, ANM-116.

   Note 3: 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

   (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.

   Note 4: The subject of this AD is addressed in French airworthiness directive 98-179-021(B), dated May 6, 1998.

   Issued in Renton, Washington, on September 3, 1999. Dorenda D. Baker, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

   [FR Doc. 99-23621Filed9-9-99; 8:45 am]

   BILLING CODE 4910-13-P