[Federal Register Volume 64, Number 175 (Friday, September 10, 1999)]
[Proposed Rules]
[Pages 49113-49115]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-23621]


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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).

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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.

[[Page 49114]]

    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 filed in 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

[[Page 49115]]

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. 99-23621 Filed 9-9-99; 8:45 am]
BILLING CODE 4910-13-P