AD 2018-04-11
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Agusta S.p.A. | Leonardo S.p.a. | AB139 | Airworthiness Directives; Agusta S.p.A. Helicopters |
| aircraft | Agusta S.p.A. | Leonardo S.p.a. | AW139 | Airworthiness Directives; Agusta S.p.A. Helicopters |
Unsafe Condition
Nonconforming thickness in a section of a tail gearbox (TGB) central housing, which can lead to a crack in the TGB central housing and result in the failure of the tail gear rotor transmission and loss of helicopter control.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Measure the thickness of the central housing in accordance with Leonardo Helicopters Bollettino Tecnico No. 139-274, dated September 14, 2016, and replace the TGB central housing before further flight if the thickness is less than 2.65 mm (0.104 inch).
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before accumulating 7,500 hours TIS for helicopters with a TGB central housing with less than 7,500 hours TIS, and within 300 hours TIS for helicopters with a TGB central housing with 7,500 or more hours TIS.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Agusta S.p.A. Model AB139 and Model AW139 helicopters, certificated in any category, with a tail gearbox (TGB) assembly part number (P/N) 3T6522A00239, 3T6522A00242, 3T6522A00243, or 3T6522A00246 that has a central housing P/N 3T6522A05144 or 3T6522A05146, all serial numbers except those listed in Table 1 of Leonardo Helicopters Bollettino Tecnico No. 139-274, dated September 14, 2016.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
We are adopting a new airworthiness directive (AD) for Agusta S.p.A. Model AB139 and Model AW139 helicopters. This AD requires inspecting the thickness of the tail gearbox (TGB) central housing (housing). This AD was prompted by reports that the housing thickness does not conform to its type design. The actions of this AD are intended to detect and correct an unsafe condition on these products.
Document Text
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[Federal Register Volume 83, Number 41 (Thursday, March 1, 2018)]
[Rules and Regulations]
[Pages 8745-8747]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2018-03929]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2017-0103; Product Identifier 2016-SW-086-AD; Amendment
39-19207; AD 2018-04-11]
RIN 2120-AA64
Airworthiness Directives; Agusta S.p.A. Helicopters
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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SUMMARY: We are adopting a new airworthiness directive (AD) for Agusta
S.p.A. Model AB139 and Model AW139 helicopters. This AD requires
inspecting the thickness of the tail gearbox (TGB) central housing
(housing). This AD was prompted by reports that the housing thickness
does not conform to its type design. The actions of this AD are
intended to detect and correct an unsafe condition on these products.
DATES: This AD is effective April 5, 2018.
The Director of the Federal Register approved the incorporation by
reference of a certain document listed in this AD as of April 5, 2018.
ADDRESSES: For service information identified in this final rule,
contact Leonardo S.p.A., Matteo Ragazzi, Head of Airworthiness, Viale
G.Agusta 520, 21017 C.Costa di Samarate (Va) Italy; telephone +39-0331-
711756; fax +39-0331-229046; or at <a href="http://www.leonardocompany.com/-/bulletins">http://www.leonardocompany.com/-/bulletins</a>. You may review the referenced service information at the
FAA, Office of the Regional Counsel, Southwest Region, 10101 Hillwood
Pkwy, Room 6N-321, Fort Worth, TX 76177. It is also available on the
internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by searching for and locating
Docket No. FAA-2017-0103.
Examining the AD Docket
You may examine the AD docket on the internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by searching for and locating Docket No. FAA-2017-
0103; or in person at Docket Operations between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays. The AD docket contains
this AD, the European Aviation Safety Agency (EASA) AD, any
incorporated-by-reference service information, the economic evaluation,
any comments received, and other information. The street address for
Docket Operations (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: Matt Fuller, Senior Aviation Safety
Engineer, Safety Management Section, Rotorcraft Standards Branch, FAA,
10101 Hillwood Pkwy, Fort Worth, TX 76177; telephone (817) 222-5110;
email <a href="/cdn-cgi/l/email-protection#eb868a9f9f838e9cc58d9e87878e99ab8d8a8ac58c849d"><span class="__cf_email__" data-cfemail="731e1207071b16045d15061f1f1601331512125d141c05">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
On September 22, 2017, at 82 FR 44363, the Federal Register
published our notice of proposed rulemaking (NPRM), which proposed to
amend 14 CFR part 39 by adding an AD that would apply to Agusta S.p.A.
Model AB139 and Model AW139 helicopters. The NPRM proposed to require
inspecting the thickness of the TGB housing and replacing the TGB
before
[[Page 8746]]
further flight if the thickness is less than 2.65 mm (0.104 inch). The
proposed requirements were intended to prevent a crack in the TGB
central housing, which could result in the failure of the tail gear
rotor transmission and loss of helicopter control.
The NPRM was prompted by AD No. 2016-0246, dated December 13, 2016,
issued by EASA, which is the Technical Agent for the Member States of
the European Union, to correct an unsafe condition for Leonardo S.p.A.
(formerly Finmeccanica S.p.A. and Agusta S.p.A.) Model AB139 and Model
AW139 helicopters.
EASA advises that the thickness of some sections of the housing do
not conform to the type design and could lead to premature cracks in
the housing, resulting in failure of the tail gear rotor transmission
and reduced control of the helicopter. The EASA AD consequently
requires a one-time inspection to determine the thickness of the
housing wall, and depending on the findings, replacing the housing or
TGB assembly with an airworthy part.
The FAA is in the process of updating Agusta S.p.A.'s name change
to Leonardo S.p.A. on its FAA type certificate. Because this name
change is not yet effective, this AD specifies Agusta S.p.A. as the
type certificate holder.
Comments
We gave the public the opportunity to participate in developing
this AD, but we received no comments on the NPRM.
FAA's 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, 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
EASA and determined the unsafe condition exists and is likely to exist
or develop on other helicopters of these same type designs and that air
safety and the public interest require adopting the AD requirements as
proposed.
Differences Between This AD and the EASA AD
If a housing has fewer than 7,500 hours TIS, the EASA AD requires a
dimensional inspection of the housing wall at a helicopter's first
return to a shop or service station for a TGB overhaul or repair after
the EASA AD's effective date but no later than 7,500 hours TIS. This AD
requires such an inspection only before reaching 7,500 hours TIS.
Related Service Information Under 1 CFR Part 51
We reviewed Leonardo Helicopters Bollettino Tecnico No. 139-274,
dated September 14, 2016 (BT 139-274), which specifies procedures for a
dimensional check of the housing or TGB to determine the thickness of
the housing wall. For housings with fewer than 7,500 flight hours, BT
139-274 specifies compliance with the dimensional check by measurement
during the next repair or overhaul, and replacing the housing if it
does not meet its thickness requirement. For housings with 7,500 or
more flight hours, BT 139-274 specifies compliance with the dimensional
check by ultrasonic inspection within 300 flight hours, and replacing
the TGB if it does not meet its thickness requirement. BT 139-274
excludes certain serial-numbered housings from the applicability
because they were inspected before delivery to customers.
This service information is reasonably available because the
interested parties have access to it through their normal course of
business or by the means identified in the ADDRESSES section.
Costs of Compliance
We estimate that this AD affects 103 helicopters of U.S. Registry
and that labor costs average $85 per work-hour. Based on these
estimates, we expect the following costs:
<bullet> Measuring the thickness of the housing requires .5 work-
hour, and no parts are needed for a total cost of $43 per helicopter.
<bullet> Ultrasonic inspecting the thickness of the housing
requires 2 work-hours, and no parts are needed for a total cost of $170
per helicopter.
<bullet> Replacing the TGB housing requires 5 work-hours, and parts
cost $11,185 for a total cost of $11,610 per helicopter.
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
rulemaking action.
Regulatory Findings
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
Order 12866;
(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
reference, Safety.
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
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. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive (AD):
2018-04-11 Agusta S.p.A.: Amendment 39-19207; Docket No. FAA-2017-
0103; Product Identifier 2016-SW-086-AD.
(a) Applicability
This AD applies to Agusta S.p.A. Model AB139 and Model AW139
helicopters, certificated in any category, with a tail gearbox (TGB)
assembly part number (P/N) 3T6522A00239, 3T6522A00242, 3T6522A00243,
or 3T6522A00246 that has a
[[Page 8747]]
central housing P/N 3T6522A05144 or 3T6522A05146, all serial numbers
except those listed in Table 1 of Leonardo Helicopters Bollettino
Technico No. 139-274, dated September 14, 2016.
(b) Unsafe Condition
This AD defines the unsafe condition as nonconforming thickness
in a section of a TGB central housing, which can lead to a crack in
the TGB central housing. This condition could result in the failure
of the tail gear rotor transmission and loss of helicopter control.
(c) Effective Date
This AD becomes effective April 5, 2018.
(d) Compliance
You are responsible for performing each action required by this
AD within the specified compliance time unless it has already been
accomplished prior to that time.
(e) Required Actions
(1) For helicopters with a TGB central housing with less than
7,500 hours time-in-service (TIS), before accumulating 7,500 hours
TIS, measure the thickness of the central housing in accordance with
the Compliance Instructions, Part I paragraphs 1. and 2., of
Leonardo Helicopters Bollettino Tecnico No. 139-274, dated September
14, 2016 (BT 139-274). If the thickness is less than 2.65 mm (0.104
inch), replace the TGB central housing before further flight.
(2) For helicopters with a TGB central housing with 7,500 or
more hours TIS, within 300 hours TIS, ultrasonic inspect the TGB in
accordance with the Compliance Instructions, Part II paragraphs 4.
through 4.5 of BT 139-274. If the thickness is less than 2.65 mm
(0.104 inch), replace the TGB before further flight.
(3) After the effective date of this AD, do not install a
central housing P/N 3T6522A05144 or 3T6522A05146, all serial numbers
except those listed in Table 1 of BT 139-274, on any helicopter
unless it has passed inspection in accordance with paragraph (e)(1)
of this AD.
(f) Special Flight Permits
Special flight permits are prohibited.
(g) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Safety Management Section, Rotorcraft Standards
Branch, FAA, may approve AMOCs for this AD. Send your proposal to:
Matt Fuller, Senior Aviation Safety Engineer, Safety Management
Section, Rotorcraft Standards Branch, FAA, 10101 Hillwood Pkwy, Fort
Worth, TX 76177; telephone (817) 222-5110; email <a href="/cdn-cgi/l/email-protection#60594d2133374d2634374d212d2f234d3205111505131413200601014e070f16"><span class="__cf_email__" data-cfemail="d6effb978581fb908281fb979b9995fb84b3a7a3b3a5a2a596b0b7b7f8b1b9a0">[email protected]</span></a>.
(2) For operations conducted under a 14 CFR part 119 operating
certificate or under 14 CFR part 91, subpart K, we suggest that you
notify your principal inspector, or lacking a principal inspector,
the manager of the local flight standards district office or
certificate holding district office, before operating any aircraft
complying with this AD through an AMOC.
(h) Additional Information
The subject of this AD is addressed in European Aviation Safety
Agency (EASA) AD No. 2016-0246, dated December 13, 2016. You may
view the EASA AD on the internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> in
Docket No. FAA-2017-0103.
(i) Subject
Joint Aircraft Service Component (JASC) Code: 6720, Tail Rotor
Control System.
(j) Material Incorporated by Reference
(1) The Director of the Federal Register approved the
incorporation by reference of the service information listed in this
paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) You must use this service information as applicable to do
the actions required by this AD, unless the AD specifies otherwise.
(i) Leonardo Helicopters Bollettino Tecnico No. 139-274, dated
September 14, 2016.
(ii) Reserved.
(3) For Leonardo Helicopters service information identified in
this AD, contact Leonardo S.p.A., Matteo Ragazzi, Head of
Airworthiness, Viale G.Agusta 520, 21017 C.Costa di Samarate (Va)
Italy; telephone +39-0331-711756; fax +39-0331-229046; or at <a href="http://www.leonardocompany.com/-/bulletins">http://www.leonardocompany.com/-/bulletins</a>.
(4) You may view this service information at FAA, Office of the
Regional Counsel, Southwest Region, 10101 Hillwood Pkwy, Room 6N-
321, Fort Worth, TX 76177. For information on the availability of
this material at the FAA, call (817) 222-5110.
(5) You may view this service information that is incorporated
by reference 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/cfr/ibr-locations.html">http://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.
Issued in Fort Worth, Texas, on February 16, 2018.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification
Service.
[FR Doc. 2018-03929 Filed 2-28-18; 8:45 am]
BILLING CODE 4910-13-P
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