[Federal Register Volume 64, Number 243 (Monday, December 20, 1999)]
[Rules and Regulations]
[Pages 71012-71014]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-32735]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 99-SW-63-AD; Amendment 39-11474; AD 99-26-14]
RIN 2120-AA64


Airworthiness Directives; Agusta S.p.A. Model AB412 Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) 
applicable to Agusta S.p.A. Model AB412 helicopters. This action 
requires removing and replacing certain main rotor yokes with airworthy 
main rotor yokes before further flight. This amendment is prompted by 
the fatigue failure of a main rotor yoke (yoke). Fatigue analysis 
indicates that certain yokes are on the low end of the manufacturer's 
tolerance for thickness and do not have the desired margin of safety. 
This condition, if not corrected, could result in fatigue failure of 
the yoke, loss of a main rotor blade, and subsequent loss of control of 
the helicopter.

DATES: Effective January 4, 2000.
    Comments for inclusion in the Rules Docket must be received on or 
before February 18, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Office of the Regional Counsel, Southwest Region, 
Attention: Rules Docket No. 99-SW-63-AD, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas 76137.
    The service information referenced in this AD may be obtained from 
Agusta, 21017 Cascina Costa di Samarate (VA), Via Giovanni Agusta 520, 
telephone (0331) 229111, fax (0331) 229605-222595. This information may 
be examined at the FAA, Office of the Regional Counsel, Southwest 
Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137.

FOR FURTHER INFORMATION CONTACT: Shep Blackman, Aerospace Engineer, 
FAA, Rotorcraft Directorate, Rotorcraft Standards Staff, 2601 Meacham 
Blvd., Fort Worth, Texas 76137, telephone (817) 222-5296, fax (817) 
222-5961.

SUPPLEMENTARY INFORMATION: The Registro Aeronautico Italiano (RAI), the 
airworthiness authority for Italy, notified the FAA that an unsafe 
condition may exist on Agusta S.p.A. Model AB412 helicopters. The RAI 
advises removing and replacing the yoke, part number (P/N) 412-010-101-
123 or -127, with an airworthy yoke, P/N 412-010-101-129.
    Agusta S.p.A. has issued Alert Bollettino Tecnico 412-74, dated 
March 16, 1999, (technical bulletin) which specifies reducing the 
retirement life of the yoke, P/N 412-010-101-123 and -127, from 5000 
hours to 4500 hours time-in-service (TIS), and replacing a yoke having 
4500 or more hours TIS with an airworthy yoke, P/N 412-010-101-129, 
which has a retirement life of

[[Page 71013]]

5000 hours. The RAI classified this technical bulletin as mandatory and 
issued AD 99-179, dated April 16, 1999, to require replacing the yoke, 
P/N 412-010-101-123 or -127, with an airworthy yoke, P/N 412-010-101-
129, before further flight, to assure the continued airworthiness of 
these helicopters in Italy.
    This helicopter model is manufactured in Italy 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 RAI has kept the FAA informed of 
the situation described above. The FAA has examined the findings of the 
RAI, 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 Agusta S.p.A. Model AB412 helicopters of the 
same type design registered in the United States, this AD is being 
issued to prevent fatigue failure of the yoke, loss of a main rotor 
blade, and subsequent loss of control of the helicopter. This AD 
requires removing and replacing a yoke, P/N 412-010-101-123 or -127, 
with an airworthy yoke, P/N 412-010-101-129, before further flight. The 
short compliance time involved is required because the previously 
described critical unsafe condition can adversely affect the structural 
integrity and controllability of the helicopter. Therefore, removing 
and replacing certain unairworthy yokes with airworthy yokes is 
required prior to further flight and this AD must be issued 
immediately.
    None of the Agusta S.p.A. Model AB412 helicopters affected by this 
action are on the U.S. Register. All helicopters included in the 
applicability of this rule currently are operated by non-U.S. operators 
under foreign registry; therefore, they are not directly affected by 
this AD action. However, the FAA considers that this rule is necessary 
to ensure that the unsafe condition is addressed in the event that any 
of these subject helicopters are imported and placed on the U.S. 
Register in the future.
    Should an affected helicopter be imported and placed on the U.S. 
Register in the future, it would require approximately 60 work hours to 
replace the yoke, at an average labor rate of $60 per work hour. 
Required parts would cost $89,742 per helicopter. Based on these 
figures, the cost impact of this AD would be $93,342 per helicopter.
    Since this AD action does not affect any helicopter that is 
currently on the U.S. Register, it has no adverse economic impact and 
imposes no additional burden on any person. Therefore, notice and 
public procedures hereon are unnecessary and the amendment may be made 
effective in less than 30 days after publication in the Federal 
Register.

Comments Invited

    Although this action is in the form of a final rule that involves 
requirements affecting flight safety and, thus, was not preceded by 
notice and an opportunity for public comment, comments are invited on 
this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
communications received on or before the closing date for comments will 
be considered, and this rule may be amended in light of the comments 
received. Factual information that supports the commenter's ideas and 
suggestions is extremely helpful in evaluating the effectiveness of the 
AD action and determining whether additional rulemaking action would be 
needed.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the rule that might 
suggest a need to modify the 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 that 
summarizes each FAA-public contact concerned with the substance of this 
AD will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this rule must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket No. 99-SW-63-AD.'' The postcard will be date stamped and 
returned to the commenter.
    The regulations adopted herein will not impose substantial direct 
compliance costs on states or local governments or 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 13132, the FAA has not consulted with 
States or local authorities prior to the publication of this rule.
    The FAA has determined no U.S. registered helicopters are affected 
by this regulation and that it is not a ``significant regulatory 
action'' under Executive Order 12866. It has been determined further 
that this action involves an emergency regulation under DOT Regulatory 
Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
determined that this emergency regulation otherwise would be 
significant under DOT Regulatory Policies and Procedures, a final 
regulatory evaluation will be prepared and placed in the Rules Docket. 
A copy of it, if filed, 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, 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 a new airworthiness directive 
to read as follows:

AD 99-26-14 AGUSTA S.p.A.: Amendment 39-11474. Docket No. 99-SW-63-
AD.
    Applicability: Model AB412 helicopters, with main rotor yoke, 
part number (P/N) 412-010-101-123 or -127, installed, 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 (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: Before further flight, unless accomplished 
previously.

[[Page 71014]]

    To prevent fatigue failure of a main rotor yoke (yoke), loss of 
a main rotor blade, and subsequent loss of control of the 
helicopter, accomplish the following:
    (a) Remove and replace each yoke, P/N 412-010-101-123 or -127, 
with an airworthy yoke, P/N 412-010-101-129.
    Note 2: Agusta S.p.A. Bollettino Tecnico 412-74, dated March 16, 
1999, pertains to the subject of this AD.

    (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, Regulations Group, FAA, 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 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Regulations Group.

    (c) Special flight permits may be issued in accordance with 
Sec. 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.
    (d) This amendment becomes effective on January 4, 2000.

    Note 4: The subject of this AD is addressed in Registro 
Aeronautico Italiano (Italy) AD 99-179, dated April 16, 1999.

    Issued in Fort Worth, Texas, on December 10, 1999.
Larry M. Kelly,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 99-32735 Filed 12-17-99; 8:45 am]
BILLING CODE 4910-13-U