[Federal Register Volume 65, Number 140 (Thursday, July 20, 2000)]
[Proposed Rules]
[Pages 44995-44997]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-18405]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-SW-25-AD]


Airworthiness Directives; Eurocopter France Model AS-350B, BA, 
B1, B2, B3, 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 the supersedure of an existing 
airworthiness directive (AD) that applies to Eurocopter France Model 
AS-350B, BA, B1, B2, C, D, and D1, and AS-355E, F, F1, and F2 
helicopters. That AD currently requires inspections of the main rotor 
head components, the main gearbox (MGB) suspension bars, and the ground 
resonance prevention system components. This action would require those 
same inspections, but would also apply to Model AS-350B3 and AS-355N 
helicopters. This proposal is prompted by the inadvertent omission of 
those model helicopters from the previous AD. The actions specified by 
the proposed AD are intended 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 on or before September 18, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 2000-SW-25-AD, 2601 Meacham Blvd., Room 
663, Fort Worth, Texas 76137. You may also send comments electronically 
to the Rules Docket at the following address: [email protected]. 
Comments may be inspected at the Office of the Regional Counsel between 
9 a.m. and 3 p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Jim Grigg, Aviation Safety 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

[[Page 44996]]

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 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 mailed 
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. 2000-SW-25-AD.'' The postcard will be date 
stamped and returned to the commenter.

Availability of NPRMs

    You 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. 2000-SW-25-AD, 2601 Meacham Blvd., Room 663, Fort Worth, 
Texas 76137.

Discussion

    On April 4, 2000, the FAA revised AD 86-15-10, Amendment 39-5517 
(52 FR 13233, April 22, 1987) by issuing AD 86-15-10 R2, Amendment 39-
11681 (65 FR 20721, April 18, 2000). That revision requires an initial 
inspection at 10 hours time-in-service (TIS) and then repetitive 
inspections at intervals not to exceed 500 hours TIS of the main rotor 
head components, the MGB suspension bars, and the ground resonance 
prevention system components. The revision was prompted by reports of 
confusion and unnecessary costs associated with the difference in the 
previously-required 400 hours TIS inspection interval and the current 
manufacturer's master service recommendation of 500 hours TIS 
inspection interval. The requirements of that revised 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.
    Since the issuance of that AD, the FAA has determined that Model 
AS-350B3 and AS-355N helicopters were inadvertently omitted from the 
applicability of the revised AD. Model AS-350B3 was omitted because it 
is a newer model helicopter and was not part of the Type Certificate 
Data Sheet when the revised AD was issued. Model AS-355N was included 
in the preamble of AD 86-15-10 R2, but was inadvertently omitted in the 
applicability list of that AD.
    Since an unsafe condition has been identified that is likely to 
exist or develop on other Model AS-350B, BA, B1, B2, B3, C, D, and D1, 
and AS-355E, F, F1, F2 and N helicopters of the same type design, the 
proposed AD would supersede AD 86-15-10, AD 86-15-10 R1, and AD 86-15-
10 R2 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 estimates that 586 helicopters of U.S. registry would be 
affected by this proposed AD, that it would take approximately 8 work 
hours per helicopter to accomplish the proposed actions, and that the 
average labor rate is $60 per work hour. Based on these figures, the 
total cost impact of the proposed AD on U.S. operators is estimated to 
be $480 per helicopter, or $281,280 for the entire fleet.
    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), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing Amendment 39-11681 (65 FR 
20721, April 18, 2000), Amendment 39-6515 (55 FR 5833, February 20, 
1990) and Amendment 39-5517 (52 FR 13233, April 22, 1987), and by 
adding a new airworthiness directive (AD), to read as follows:

Eurocopter France: Docket No. 2000-SW-25-AD. Supersedes AD 86-15-10 
R2, Amendment 39-11681, Docket No. 98-SW-82-AD; AD 86-15-10R1, 
Amendment 39-6515, Docket No. 86-ASW-22; and AD 86-15-10, Amendment 
39-5517, Docket No. 86-ASW-22.

    Applicability: Model AS-350B, BA, B1, B2, B3, C, D, and D1, and 
AS-355E, F, F1, F2 and N 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 
otherwise 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 request approval for an 
alternative method of compliance in accordance with paragraph (f) 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 ground resonance due to reduced structural stiffness, 
which could lead to failure of a main rotor head or main gearbox 
(MGB) suspension component and 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, B3, 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

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Aerospatiale Service Bulletin (SB) No. 01.17a (not dated).
    (2) For Model AS-355E, F, F1, F2, and N 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 
(struts) before further flight.
    (e) After a landing with abnormal self-sustained dynamic 
vibrations (ground resonance type vibrations), repeat all the 
inspections required by 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, Regulations Group, Rotorcraft 
Directorate, FAA. 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 
Secs. 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 July 12, 2000.
Henry A. Armstrong,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 00-18405 Filed 7-19-00; 8:45 am]
BILLING CODE 4910-13-U