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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-365-AD; Amendment 39-11402; AD 99-23-06]

RIN 2120-AA64

Airworthiness Directives; Aerospatiale Model SN-601 (Corvette)

Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD),

applicable to all Aerospatiale Model SN-601 (Corvette) series

airplanes, that requires 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 also requires replacement of seals

and backup rings with new parts. This amendment is prompted by issuance

of mandatory continuing airworthiness information by a foreign civil

airworthiness authority. The actions specified by this 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: Effective December 17, 1999.

The incorporation by reference of certain publications listed in

the regulations is approved by the Director of the Federal Register as

of December 17, 1999.

ADDRESSES: The service information referenced in this AD may be

obtained from Aerospatiale, 316 Route de Bayonne, 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.

FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager,

International Branch, ANM-116, FAA, Transport Airplane Directorate,

1601

[[Page 61476]]

Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-

2110; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION: 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 all Aerospatiale Model SN-601

(Corvette) series airplanes was published in the Federal Register on

September 10, 1999 (64 FR 49113). That action proposed to 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. That

action also proposed to require replacement of seals and backup rings

with new parts.

Comments

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.

Conclusion

The FAA has determined that air safety and the public interest

require the adoption of the rule as proposed.

Cost Impact

The FAA estimates that 2 airplanes of U.S. registry will be

affected by this AD, that it will take approximately 8 work hours per

airplane to accomplish the inspection, and that the average labor rate

is $60 per work hour. The cost of required parts will be minimal. Based

on these figures, the cost impact of this 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 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 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. 106(g), 40113, 44701.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding the following new

airworthiness directive:

99-23-06 Aerospatiale: Amendment 39-11402. 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 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.

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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.

Incorporation by Reference

(d) The actions shall be done in accordance with Messier-Dowty

Technical Instruction No. 20403, Issue 2, dated March 1998. 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.

Note 4: The subject of this AD is addressed in French

airworthiness directive 98-179-021(B), dated May 6, 1998.

(e) This amendment becomes effective on December 17, 1999.

Issued in Renton, Washington, on October 28, 1999.

D.L. Riggin,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 99-28745 Filed 11-10-99; 8:45 am]

BILLING CODE 4910-13-U