AGENCY: Federal Aviation Administration
ACTION: Final rule.
SUMMARY: We are adopting a new airworthiness directive (AD) for
S.p.A. (Agusta) Model AB139 and AW139 helicopters with a certain
generator control unit (GCU), to require replacing each affected GCU
with an airworthy GCU. This AD was prompted by laboratory tests which
revealed a potential fault in the overvoltage protection on a certain
part-numbered GCU. The actions are intended to prevent failure of the
overvoltage protection of the GCU, degraded performance of the
electrical power generation and distribution systems, a fire, and
subsequent loss of control of the helicopter.
DATES: This AD is effective July 30, 2012.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of July 30,
ADDRESSES: For service information identified in this AD, contact
Agusta Westland, Customer Support & Services, Via Per Tornavento 15,
21019 Somma Lombardo (VA) Italy, ATTN: Giovanni Cecchelli; telephone
39-0331-711133; fax 39 0331 711180; or at http://www.agustawestland.com/
technical-bullettins. You may review a copy of
the referenced service information at the FAA, Office of the Regional
Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth,
Examining the AD Docket: You may examine the AD docket on the
Internet at http://www.regulations.gov; or in person at the Docket Operations
Office between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains this AD, any incorporated-by-reference
service information, the economic evaluation, any comments received,
and other information. The street address for the Docket Operations
Office (phone: 800-647-5527) is U.S. Department of Transportation,
Docket Operations Office, M-30, West Building Ground Floor, Room W12-
140, 1200 New Jersey Avenue SE., Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Mark Wiley, Aerospace Engineer,
Regulations and Policy Group, Rotorcraft Directorate, 2601 Meacham
Blvd., Fort Worth, Texas 76137; telephone (817) 222-5134; fax (817)
222-5961; email firstname.lastname@example.org.
On January 20, 2012, at 77 FR 2926, the Federal Register published
our Notice of Proposed Rulemaking (NPRM), which proposed to amend 14
CFR part 39 to include an AD that would apply to Agusta Model AB139 and
AW139 helicopters, with a GCU, part-number (P/N) 1152550-3, installed.
That NPRM proposed to require, within 6 months, removing the No. 1 and
No. 2 GCU, P/N 1152550-3, modifying the electrical connectors A13P1 and
A14P1 by installing wiring to the power distribution panel, and
installing a No. 1 and No. 2 GCU with P/N 1152550-4 or 1152550-5. Both
GCUs must have identical P/Ns on the same helicopter. The proposed
requirements were intended to prevent failure of the overvoltage
protection of the GCU, degraded performance of the electrical power
generation and distribution systems, a fire, and subsequent loss of
control of the helicopter.
The European Aviation Safety Agency (EASA), which is the Technical
Agent for the Member States of the European Union, has issued EASA AD
No. 2009-0042, dated February 25, 2009 (AD 2009-0042), to correct an
unsafe condition for the Agusta Model AB139 and AW139 helicopters, all
serial numbers (S/Ns) except S/Ns 31002, 31003, 31004, and
31007. EASA advises that laboratory tests performed on a new GCU model
under development have shown a potential fault in the overvoltage
protection of currently installed GCUs, P/N 1152550-3. EASA also
advises that this condition, if not corrected, could adversely affect
the helicopter's electrical power generation and distribution system
We gave the public the opportunity to participate in developing
this AD, but we did not receive any comments on the NPRM.
These helicopters have been approved by the aviation authority of
Italy and are approved for operation in the United States. Pursuant to
our bilateral agreement with Italy, the EASA, its technical
representative, has notified us of the unsafe condition described in
the EASA AD. We are issuing this AD because we evaluated all
information provided by the EASA and determined that an unsafe
condition exists and is likely to exist or develop on other helicopters
of these same type designs. We have determined that air safety and the
public interest require adopting the AD requirements as proposed,
except for a typographical correction in the Related Service
Information paragraph of the NPRM, which referred to the EASA AD as
``2009-0048'' instead of ``2009-0042.'' This change is consistent with
the intent of the proposals in the NPRM and will not increase the
economic burden on any operator nor increase the scope of the AD.
Differences Between This AD and the EASA AD
The EASA AD does not apply to certain serial-numbered Model AB139
and AW139 helicopters, whereas this AD applies to all serial-numbered
Model AB139 and AW139 helicopters.
Related Service Information
Agusta S.p.A. issued Mandatory Bollettino Tecnico No. 139-133, Rev.
A, dated March 17, 2009 (BT), for Model AB139 and AW139 helicopters,
S/Ns 31005 up to S/N 31143, except for S/Ns 31007, 31037,
31038, 31094; S/N 31112; S/Ns 31146 up to S/N 31148;
S/N 31155; S/Ns 31201 up to S/N 31218; and S/Ns 41001
up to S/N 41022, except S/N 41007; with a GCU, P/N 1152550-3.
This BT specifies, within 6 months from receipt of the BT, removing
GCU, P/N 1152550-3, modifying electrical connector A13P1 and A14P1, and
replacing each GCU with an airworthy GCU, P/N 1152550-4 or 1152550-5,
to improve electrical power generation and distribution system
functionalities. EASA classified this BT as mandatory and issued AD
2009-0042 to ensure the continued airworthiness of these helicopters.
Costs of Compliance
We estimate that this AD will affect 72 helicopters of U.S.
We estimate that operators may incur the following costs in order
to comply with this AD. We estimate that it will take about 4 work-
hours to perform the required actions of this AD per helicopter at an
average labor rate of $85 per work-hour, and required parts will cost
about $42,384 per helicopter. Based on these figures, we estimate the
cost to be $42,724 per helicopter and the total cost impact of the AD
for U.S. operators to be $3,076,128.
According to the Agusta service information some of the costs of
this AD may be covered under warranty, thereby reducing the cost impact
on affected individuals. We do not control warranty coverage by Agusta.
Accordingly, we have included all costs in our cost estimate.
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, section 106, describes the
authority of the FAA Administrator. Subtitle VII: Aviation Programs,
describes in more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in
Subtitle VII, Part A, Subpart III, Section 44701: ``General
requirements.'' Under that section, Congress charges the FAA with
promoting safe flight of civil aircraft in air commerce by prescribing
regulations for practices, methods, and procedures the Administrator
finds necessary for safety in air commerce. This regulation is within
the scope of that authority because it addresses an unsafe condition
that is likely to exist or develop on helicopters identified in this
This AD will not have federalism implications under Executive Order
13132. This AD will 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.
For the reasons discussed above, I certify that this AD:
(1) Is not a ``significant regulatory action'' under Executive
(2) Is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979);
(3) Will not affect intrastate aviation in Alaska to the extent
that it justifies making a regulatory distinction; and
(4) 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.
We prepared an economic evaluation of the estimated costs to comply
with this AD and placed it in the AD docket.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
Adoption of the Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 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. The FAA amends Sec. 39.13 by adding the following new airworthiness