AD 2011-20-08

final rule

Airworthiness Directives; Agusta S.p.A. (Agusta) Model AB139 and AW139 Helicopters

AD Number
2011-20-08
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2011-1036
FR Citation
76 FR 68297

Applicability

TypeManufacturerModelDetails
aircraft Agusta S.p.A. AB139 Airworthiness Directives; Agusta S.p.A. (Agusta) Model AB139 and AW139 Helicopters
aircraft Agusta S.p.A. AW139 Airworthiness Directives; Agusta S.p.A. (Agusta) Model AB139 and AW139 Helicopters

Unsafe Condition

Internal corrosion of the Number 2 Modular Avionic Unit (MAU) circuit card assemblies, which can result from exposure to external moisture via the ventilation duct installation, leading to false indications or misleading data displayed to the flight crew, disengagement of flight director modes, and increased workload that could lead to loss of control.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Inspect certain modules and related connectors for corrosion. Clean connectors if corrosion is found. Replace modules with airworthy ones if corrosion is present. Modify the Number 2 Modular Avionic Unit (MAU) ventilation duct to reroute airflow away from the MAU2 cabinet and modules.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 30 hours time-in-service or 1 month, whichever occurs first.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Agusta S.p.A. Model AB139 and AW139 helicopters.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

This amendment adopts a new airworthiness directive (AD) for the specified Agusta model helicopters. This action requires inspecting certain modules and related connectors for corrosion. If there is corrosion on the connectors, this AD requires cleaning the connectors before further flight. If there is corrosion on a module, before further flight, this AD requires replacing the module with an airworthy module. This AD also requires modifying the Number 2 Modular Avionic Unit (MAU) ventilation duct. This amendment is prompted by some in- flight emergencies due to internal corrosion of the MAU circuit card assemblies. The actions specified in this AD are intended to detect corrosion of certain modules to prevent the display of misleading data to the flight crew, disengagement of the flight director modes of the autopilot or other alert system, increased workload of the flight crew, and subsequent loss of control of the helicopter.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 76, Number 214 (Friday, November 4, 2011)]
[Rules and Regulations]
[Pages 68297-68299]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2011-27772]



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Rules and Regulations
                                                Federal Register
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This section of the FEDERAL REGISTER contains regulatory documents 
having general applicability and legal effect, most of which are keyed 
to and codified in the Code of Federal Regulations, which is published 
under 50 titles pursuant to 44 U.S.C. 1510.

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Federal Register / Vol. 76, No. 214 / Friday, November 4, 2011 / 
Rules and Regulations

[[Page 68297]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-1036; Directorate Identifier 2010-SW-088-AD; 
Amendment 39-16819; AD 2011-20-08]
RIN 2120-AA64


Airworthiness Directives; Agusta S.p.A. (Agusta) Model AB139 and 
AW139 Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

-----------------------------------------------------------------------

SUMMARY: This amendment adopts a new airworthiness directive (AD) for 
the specified Agusta model helicopters. This action requires inspecting 
certain modules and related connectors for corrosion. If there is 
corrosion on the connectors, this AD requires cleaning the connectors 
before further flight. If there is corrosion on a module, before 
further flight, this AD requires replacing the module with an airworthy 
module. This AD also requires modifying the Number 2 Modular Avionic 
Unit (MAU) ventilation duct. This amendment is prompted by some in-
flight emergencies due to internal corrosion of the MAU circuit card 
assemblies. The actions specified in this AD are intended to detect 
corrosion of certain modules to prevent the display of misleading data 
to the flight crew, disengagement of the flight director modes of the 
autopilot or other alert system, increased workload of the flight crew, 
and subsequent loss of control of the helicopter.

DATES: Effective November 21, 2011.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of November 21, 2011.
    Comments for inclusion in the Rules Docket must be received on or 
before January 3, 2012.

ADDRESSES: Use one of the following addresses to submit comments on 
this AD:
    <bullet> Federal eRulemaking Portal: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a>. Follow the instructions for submitting comments.
    <bullet> Fax: (202) 493-2251.
    <bullet> Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590.
    <bullet> Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    You may get the service information identified in this AD from 
Agusta, Via Giovanni Agusta, 520 21017 Cascina Costa di Samarate (VA), 
Italy, telephone 39 0331-229111, fax 39 0331-229605/222595, or at 
<a href="http://customersupport.agusta.com/technical_advice.php">http://customersupport.agusta.com/technical_advice.php</a>.
    Examining the Docket: You may examine the docket that contains the 
AD, any comments, and other information on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a>, or in person at the Docket Operations office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Operations office (telephone (800) 647-5527) is 
located in Room W12-140 on the ground floor of the West Building at the 
street address stated in the ADDRESSES section. Comments will be 
available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: George Schwab, Aviation Safety 
Engineer, FAA, Rotorcraft Directorate, Safety Management Group, 2601 
Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5114, fax 
(817) 222-5961.

SUPPLEMENTARY INFORMATION: 

Discussion

    The European Aviation Safety Agency (EASA), which is the Technical 
Agent for the Member States of the European Union, has issued EASA AD 
No. 2010-0189, dated September 23, 2010, to correct an unsafe condition 
for the Agusta Model AB139 and AW139 helicopters. EASA advises of some 
in-flight emergencies resulting from internal corrosion of the MAU2 
circuit card assemblies. Analysis of the in-flight emergencies 
identified salt water and extreme moisture as contributory factors. The 
corrosion resulted from the MAU2 being exposed to external moisture as 
a result of the ventilation duct installation that routes external air 
directly on the MAU2 modules. When exposed to high levels of moisture, 
EASA states the MAU can cause the system to provide false indications 
or misleading data to be displayed to the flight crew. Also, misleading 
data may cause disengagement of the flight director modes of the 
autopilot or other alerting system anomalies. They also state that 
these failures and anomalies would significantly increase the workload 
of the flight crew and could ultimately lead to loss of control of the 
helicopter.

Related Service Information

    Agusta has issued Bollettino Tecnico No. 139-166, dated April 6, 
2009 (BT), which specifies inspecting the MAU2 cards to ensure they are 
corrosion free. Also, the BT specifies procedures for modifying to 
reroute the direct flow of air coming from the ventilation duct outlet 
MAU2 ventilation away from the MAU2 cabinet and modules. EASA 
classified this service information as mandatory and issued AD No. 
2010-0189, dated September 23, 2010, to ensure the continued 
airworthiness of these helicopters.

FAA's Evaluation and Unsafe Condition Determination

    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, EASA, their 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 EASA and determined the unsafe condition exists 
and is likely to exist or develop on other helicopters of these same 
type designs.

Differences Between This AD and the EASA AD

    We do not require reporting inspection results nor coordinating 
with the manufacturer in returning modules as indicated in the BT that 
EASA

[[Page 68298]]

references. Also, we have used a different compliance time for the 
action.

FAA's Determination and Requirements of This AD

    This unsafe condition is likely to exist or develop on other 
helicopters of the same type design. Therefore, this AD is being issued 
to detect corrosion of certain modules, to prevent the display of 
misleading data, disengagement of the flight director modes of the 
autopilot or other alert system anomalies, increased workload of the 
flight crew, and subsequent loss of control of the helicopter. This AD 
requires, at a specified interval, inspecting certain modules and 
related connectors for corrosion. If there is corrosion on the 
connectors, this AD requires cleaning the connectors before further 
flight. If there is corrosion on a module, this AD requires replacing 
the module with an airworthy module. This AD also requires modifying 
the MAU2 ventilation duct.
    The short compliance time involved is required because the 
previously described critical unsafe condition can adversely affect the 
controllability of the helicopter. Therefore, inspecting, replacing, or 
modifying certain modules is required within a very short compliance 
time, 30 hours time-in-service or 1 month, whichever occurs first, so 
this AD must be issued immediately.
    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

Costs of Compliance

    We estimate that this AD will affect about 26 helicopters of U.S. 
registry. We also estimate that it will take 6 work hours to remove, 
inspect the modules for corrosion, and replace the corroded modules, 
and 2 work hours to reroute the ventilation tube. The average labor 
rate is $85 per work-hour. Required parts will cost about $360,738 per 
helicopter to replace corroded modules and $440 for parts to modify the 
ventilation tube. Based on these figures, we estimate the cost of this 
AD on U.S. operators is $361,858 per helicopter or $9,408,308 for the 
U.S. fleet, assuming the modules would be replaced on the entire fleet.

Comments Invited

    This AD is a final rule that involves requirements that affect 
flight safety and was not preceded by notice and an opportunity for 
public comment; however, we invite you to submit any written data, 
views, or arguments regarding this AD. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2011-1036; Directorate 
Identifier 2010-SW-088-AD'' at the beginning of your comments. We 
specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of the AD. We will consider all 
comments received by the closing date and may amend the AD in light of 
those comments.
    We will post all comments we receive, without change, to <a href="http://www.regulations.gov">http://www.regulations.gov</a>, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact 
with FAA personnel concerning this AD. Using the search function of the 
docket Web site, you can find and read the comments to any of our 
dockets, including the name of the individual who sent the comment. You 
may review the DOT's complete Privacy Act Statement in the Federal 
Register published on April 11, 2000 (65 FR 19477-78).

Regulatory Findings

    We have determined that 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 the 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. 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. See the AD docket to examine the economic evaluation.

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 products identified in this 
rulemaking action.

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

0
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]

0
2. Section 39.13 is amended by adding a new airworthiness directive to 
read as follows:

2011-20-08 AGUSTA S.p.A.: Amendment 39-16819; Docket No. FAA-2011-
1036; Directorate Identifier 2010-SW-088-AD.

    Applicability: Models AB139 and AW139 helicopters, serial number 
(S/N) 31005 through S/N 31157 (except S/Ns 31007, 31094 and 31149) 
and S/N 41001 through S/N 41023, certificated in any category.
    Compliance: Within 30 hours time-in-service (TIS) or 30 days, 
whichever occurs earlier, unless done previously:
    To detect corrosion of certain modules, to prevent the display 
of misleading data to the flight crew, disengagement of the flight 
director modes of the autopilot or other alert system, increased 
workload of the flight crew, and subsequent loss of control of the 
helicopter, do the following:
    (a)(1) Remove the following items related to the Numbers 1 and 2 
Modular Avionics Unit (MAU):
    (i) Power supply (PS) module, part number (P/N) 7024440-1901;
    (ii) Custom Input/Output (CSIO) module, P/N 7025410-1901;
    (iii) Control Input/Output (CIO) module, P/N 7026534-1902;
    (iv) MAU cabinet; and
    (2) Inspect the PS, CSIO, CIO, and MAU cabinet and all related 
connectors for corrosion.
    (i) If there is corrosion on a connector, before further flight, 
clean the connector.

[[Page 68299]]

    (ii) If there is corrosion on a module, before further flight, 
replace the module with an airworthy module.
    (b) Modify the Number 2 MAU ventilation duct by following the 
Compliance Instructions, paragraphs 6 through 11, of Agusta 
Bollettino Tecnico No. 139-166, dated April 6, 2009 (BT).
    (c) Install and operationally test the Number 1 and Number 2 
MAUs and the related PS module, CSIO module, CIO module, MAU 
cabinet, and all related connectors.
    (d) Reinstall the AFT right float assembly or the lower panel, 
P/N 3P5340A01631, whichever was removed during the modification 
process required by paragraph (b) of this AD.
    (e) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Contact the Manager, Safety Management Group, ATTN: George Schwab, 
Aviation Safety Engineer, FAA, Rotorcraft Directorate, Safety 
Management Group, 2601 Meacham Blvd., Fort Worth, Texas 76137, 
telephone (817) 222-5114, fax (817) 222-5961.
    (f) The Joint Aircraft System/Component (JASC) Code is 3425: 
Navigation, Integrated Flight Director System.
    (g) Modifying the ventilation duct shall be done by following 
specified portions of Agusta Bollettino Tecnico No. 139-166, dated 
April 6, 2009. The Director of the Federal Register approved this 
incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 
CFR part 51. Copies may be obtained from Agusta, Via Giovanni 
Agusta, 520 21017 Cascina Costa di Samarate (VA), Italy, telephone 
39 0331-229111, fax 39 0331-229605/222595, or at <a href="http://customersupport.agusta.com/technical_advice.php">http://customersupport.agusta.com/technical_advice.php</a>. Copies may be 
inspected at the FAA, Office of the Regional Counsel, Southwest 
Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas, or at the 
National Archives and Records Administration (NARA). For information 
on the availability of this material at NARA, call (202) 741-6030, 
or go to: <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
    (h) This amendment becomes effective on November 21, 2011.


    Note: The subject of this AD is addressed in the European 
Aviation Safety Agency (Italy) AD No. 2010-0189, dated September 23, 
2010.


    Issued in Fort Worth, Texas, on August 29, 2011.
Kim Smith,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2011-27772 Filed 11-3-11; 8:45 am]
BILLING CODE 4910-13-P

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