[Federal Register Volume 65, Number 13 (Thursday, January 20, 2000)]
[Proposed Rules]
[Pages 3165-3167]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-1370]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-SW-82-AD]


Airworthiness Directives; Eurocopter France Model AS-350B, BA, 
B1, B2, C, D, and D1, and AS-355E, F, F1, F2 and N Helicopters

AGENCY:  Federal Aviation Administration, DOT.

ACTION:  Notice of proposed rulemaking (NPRM).

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SUMMARY:  This document proposes to revise an existing airworthiness 
directive (AD), applicable to Aerospatiale (Societe Nationale 
Industrielle Aerospatiale) (SNIAS) (now known as Eurocopter France) 
Model AS 350 and AS 355 series helicopters that currently requires 
repetitive inspections of the main rotor head components, the main 
gearbox (MGB) suspension bars, and the ground resonance prevention 
system components at intervals not to exceed 400 hours time-in-service 
(TIS). This action would require the same inspections, but at intervals 
not to exceed 500 hours TIS. This proposal is prompted by reports of 
confusion and unnecessary costs associated with the difference in the 
current 400 hours TIS inspection interval and the current 
manufacturer's master service recommendation of 500 hours TIS 
inspection interval. The actions specified by the proposed AD are 
intended to eliminate confusion and unnecessary costs and to prevent 
ground resonance due to reduced structural stiffness, which could lead 
to failure of a main rotor head or MGB suspension component and 
subsequent loss of control of the helicopter.

DATES:  Comments must be received by March 20, 2000.

ADDRESSES:  Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 98-SW-82-AD, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas 76137. Comments may be inspected at this location 
between 9 a.m. and 3 p.m., Monday through Friday, except Federal 
holidays.
    The service information referenced in the proposed rule may be 
obtained from American Eurocopter Corporation, 2701 Forum Drive, Grand 
Prairie, Texas 75053-4005, telephone (972) 641-3460, fax (972) 641-
3527. This information may be examined at the FAA, Office of the 
Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort 
Worth, Texas.

FOR FURTHER INFORMATION CONTACT: Jim Grigg, Aerospace Engineer, FAA, 
Rotorcraft Directorate, Rotorcraft Standards Staff, 2601 Meacham Blvd., 
Fort Worth, Texas 76137, telephone (817) 222-5490, fax (817) 222-5961.

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 should identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before

[[Page 3166]]

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.
    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 No. 98-SW-82-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, Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 98-SW-82-AD, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas 76137.

Discussion

    Following the issuance of our emergency priority letter AD on July 
30, 1986, on March 3, 1987, the FAA issued AD 86-15-10, Amendment 39-
5517 (52 FR 13233, April 22, 1987), to require an initial inspection 
within 10 hours time-in-service and repetitive inspections of the main 
rotor head components, the MGB suspension bars, and the ground 
resonance prevention system components at intervals not to exceed 300 
hours TIS. That action was prompted by three reports of main rotor head 
component damage and MGB suspension bar damage in Model AS 355 
helicopters that exhibited severe vibrations on approach or landing. 
That condition, if not corrected, could result in failure or 
unacceptable deterioration of the main rotor head, MGB suspension, or 
ground resonance prevention components which could result in failure of 
a main rotor head or MGB suspension component, and subsequent loss of 
control of the helicopter. On February 8, 1990, the FAA revised AD 86-
15-10 (55 FR 5833, February 20, 1990), to require the same actions, 
except the repetitive inspections were required at intervals not to 
exceed 400 hours TIS. That action was prompted by reports of confusion 
and unnecessary costs caused by the differences in inspection intervals 
between AD 86-15-10 and the manufacturer's service bulletins that were 
incorporated by reference into that AD.
    Since the issuance of that AD, no further incidents have occurred. 
The master maintenance interval has shifted from 400 to 500 hours TIS. 
Since flight safety will not be adversely impacted, and to alleviate 
any confusion between the AD and the master maintenance interval, the 
FAA proposes to revise the AD to match the master maintenance interval.
    These helicopter models are manufactured in France and are 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 Direction Generale De L'Aviation 
Civile (DGAC) has kept the FAA informed of the situation described 
above. The FAA has 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.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other Eurocopter France AS-350B, BA, B1, B2, C, D, 
and D1, and AS-355E, F, F1, F2 helicopters of the same type design, the 
proposed AD would revise AD 86-15-10 R1 to require repetitive 
inspections of the main rotor head components, the MGB suspension bars, 
and the ground resonance prevention system components at intervals not 
to exceed 500 hours TIS.
    The FAA has determined that this regulation is relieving in nature 
and imposes no additional costs or regulatory burden on any person.
    The regulations proposed herein would not have a substantial direct 
effect 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, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    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), 40114, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing Amendment 39-5517 (52 FR 
13233, April 22, 1987) and Amendment 39-6515 (55 FR 5833, February 20, 
1990), and by adding a new airworthiness directive (AD), to read as 
follows:

Eurocopter France: Docket No. 98-SW-82-AD. Revises AD 86-15-10, 
Amendment 39-5517 and AD 86-15-10 R1, Amendment 39-6515.

    Applicability: Model AS-350B, BA, B1, B2, C, D, and D1, and AS-
355E, F, F1, F2 helicopters, certificated in any category.

    Note 1:  This AD applies to each helicopter 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 helicopters 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 (f) 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 helicopter from the applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent ground resonance due to reduced structural stiffness, 
which could lead to failure of a main rotor head or main gearbox 
(MBG) suspension component and

[[Page 3167]]

subsequent loss of control of the helicopter, accomplish the 
following:
    (a) Within 10 hours time-in-service (TIS):
    (1) For Model AS-350B, BA, B1, B2, C, D, and D1 helicopters, 
inspect the main rotor head components, the MGB suspension bars 
(struts), and the landing gear ground resonance prevention 
components (aft spring blades and hydraulic shock absorbers) in 
accordance with paragraph CC.3 of Aerospatiale Service Bulletin (SB) 
No. 01.17a (not dated).
    (2) For Model AS-355E, F, F1, F2 helicopters, inspect the main 
rotor head components, the MGB suspension bars (struts), and the 
landing gear ground resonance prevention components (aft spring 
blades and hydraulic shock absorbers) in accordance with paragraph 
CC.3 of SB No. 01.14a (not dated).
    (b) Rework or replace damaged components in accordance with SB 
No. 01.17a or SB No. 01.14a, as applicable.
    (c) Repeat the inspections and rework required by paragraphs (a) 
and (b) of this AD at intervals not to exceed 500 hours TIS.
    (d) If the helicopter is subjected to a hard landing or to high 
surface winds, when parked without effective tiedown straps 
installed, repeat the inspections required by paragraph (a) of this 
AD for the main rotor head star arms and the MGB suspension bars 
before further flight.
    (e) In the event of a landing which exhibits abnormal self-
sustained dynamic vibrations (ground resonance type vibrations), 
repeat all the inspections contained in paragraph (a) of this AD.
    (f) 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, FAA, Regulations Group, Rotorcraft 
Directorate. Operators shall submit their requests through an FAA 
Principal Maintenance Inspector, who may concur or comment and then 
send it to the Manager, Regulations Group.

    Note 2:  Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Regulations Group.

    (g) 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 helicopter to a location where 
the requirements of this AD can be accomplished.

    Issued in Fort Worth, Texas, on January 11, 2000.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 00-1370 Filed 1-19-00; 8:45 am]
BILLING CODE 4910-13-U