AD 2020-21-15

final rule

Airworthiness Directives; Airbus Helicopters

AD Number
2020-21-15
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2020-0618
FR Citation
85 FR 69131

Applicability

TypeManufacturerModelDetails
aircraft Airbus Helicopters AS-365N2 Airworthiness Directives; Airbus Helicopters
aircraft Airbus Helicopters AS-365N3 Airworthiness Directives; Airbus Helicopters
aircraft Airbus Helicopters EC 155B Airworthiness Directives; Airbus Helicopters
aircraft Airbus Helicopters EC155B1 Airworthiness Directives; Airbus Helicopters
aircraft Airbus Helicopters SA-365N1 Airworthiness Directives; Airbus Helicopters

Unsafe Condition

A foreign object obstructing the oil duct of a TGB control bearing, which could affect the correct operation of the TGB and possibly result in reduced control of the helicopter.

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

Required Actions

Inspect the TGB housing recess and TGB oil duct housing, and depending on the findings, perform applicable investigative and corrective actions. If oil retention is found and the two T holes are not visible, remove the TGB control rod and inspect for and remove any foreign objects in the TGB oil duct. If oil retention is found and the two T holes are not visible after additional inspections, mark the TGB as not fit for helicopter installation and return it to Airbus Helicopters. If no oil retention is found and the two T holes are visible after additional inspections, remove any foreign objects in the TGB oil duct and inspect for proper oil flow at the end of the BTP oil duct cover. If the oil does not flow properly, mark the TGB as not fit for helicopter installation and return it to Airbus Helicopters. If the oil flows properly, replace the TGB control rod bearing with a new bearing.

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

Compliance Time

Within 55 hours time-in-service or 5 months, whichever occurs first.

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

Affected Aircraft

Airbus Helicopters Model AS-365N2, AS 365 N3, EC 155B, EC155B1, and SA-365N1 helicopters.

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

Federal Register Abstract

The FAA is adopting a new airworthiness directive (AD) for Airbus Helicopters Model AS-365N2, AS 365 N3, EC 155B, EC155B1, and SA- 365N1 helicopters. This AD requires inspecting the tail rotor gearbox (TGB) housing recess, and depending on the inspection results, performing more in-depth inspections and removing certain parts from service. This AD also prohibits installing a TGB unless it has passed certain inspections and has a new TGB control rod bearing installed. This AD was prompted by the discovery of a foreign object obstructing the oil duct of a TGB control bearing. The actions of this AD are intended to address an unsafe condition on these products.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 85, Number 212 (Monday, November 2, 2020)]
[Rules and Regulations]
[Pages 69131-69134]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2020-23977]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0618; Product Identifier 2019-SW-064-AD; Amendment 
39-21288; AD 2020-21-15]
RIN 2120-AA64


Airworthiness Directives; Airbus Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
Airbus Helicopters Model AS-365N2, AS 365 N3, EC 155B, EC155B1, and SA-
365N1 helicopters. This AD requires inspecting the tail rotor gearbox 
(TGB) housing recess, and depending on the inspection results, 
performing more in-depth inspections and removing certain parts from 
service. This AD also prohibits installing a TGB unless it has passed 
certain inspections and has a new TGB control rod bearing installed. 
This AD was prompted by the discovery of a foreign object obstructing 
the oil duct of a TGB control bearing. The actions of this AD are 
intended to address an unsafe condition on these products.

DATES: This AD is effective December 7, 2020.
    The Director of the Federal Register approved the incorporation by 
reference of certain documents listed in this AD as of December 7, 
2020.

ADDRESSES: For service information identified in this final rule, 
contact Airbus Helicopters, 2701 N. Forum Drive, Grand Prairie, TX 
75052; telephone 972-641-0000 or 800-232-0323; fax 972-641-3775; or at 
<a href="https://www.airbus.com/helicopters/services/technical-support.html">https://www.airbus.com/helicopters/services/technical-support.html</a>. You 
may view 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="https://www.regulations.gov">https://www.regulations.gov</a> by searching for and locating Docket No. FAA-2020-
0618.

Examining the AD Docket

    You may examine the AD docket on the internet at <a href="https://www.regulations.gov">https://www.regulations.gov</a> by searching for and locating Docket No. FAA-2020-
0618; 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 Union Aviation Safety Agency

[[Page 69132]]

(EASA) AD, any service information that is incorporated by reference, 
any comments received, and other information. The street address for 
Docket Operations is U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Rao Edupuganti, Aviation Safety 
Engineer, Regulations and Policy Section, Rotorcraft Standards Branch, 
FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone 817-222-
5110; email <a href="/cdn-cgi/l/email-protection#fd8f9c92d39899888d889a9c938994bd9b9c9cd39a928b"><span class="__cf_email__" data-cfemail="7f0d1e10511a1b0a0f0a181e110b163f191e1e51181009">[email&#160;protected]</span></a>.

SUPPLEMENTARY INFORMATION:

Discussion

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to Airbus Helicopters 
Model AS-365N2, AS 365 N3, EC 155B, EC155B1, and SA-365N1 helicopters. 
The NPRM published in the Federal Register on June 23, 2020 (85 FR 
37591). The NPRM proposed to require opening the TGB oil filter plug 
cover and removing the TGB oil filter plug, and then borescope 
inspecting for oil retention and visibility of the two T holes in the 
TGB housing recess. If there is any oil retention and the two T holes 
are not completely visible, the NPRM proposed to require removing the 
TGB control rod and inspecting for and removing any foreign object in 
the TGB oil duct. The NPRM also proposed to require re-inspecting the 
TGB housing recess with all of the oil drained. If, during the re-
inspection, there is any oil retention and the two T holes are not 
completely visible, the NPRM proposed to require replacing the TGB. If, 
during the re-inspection, there is no oil retention and the two T holes 
are completely visible, the NPRM proposed to require inspecting for and 
removing any foreign object from the TGB oil duct and inspecting the 
TGB oil duct for correct oil flow. If the oil does not flow correctly, 
the NPRM proposed to require replacing the TGB. If the oil flows 
correctly, the NPRM proposed to require removing the TGB control rod 
bearing from service. The NPRM also proposed to prohibit the 
installation of a TGB unless it passes the proposed inspections. A non-
installed TGB would be inspected in a level position using shims.
    The NPRM was prompted by EASA AD No. 2019-0165-E, dated July 12, 
2019, issued by EASA, which is the Technical Agent for the Member 
States of the European Union, to correct an unsafe condition for Airbus 
Helicopters (formerly Eurocopter, Eurocopter France, Aerospatiale, Sud 
Aviation) Model AS 365 N2, AS 365 N3, EC 155 B, EC 155 B1, and SA 365 
N1 helicopters. EASA advises of a foreign object that was found 
obstructing the oil duct of the TGB control bearing during a routine 
inspection, causing a lack of lubrication on the bearing. EASA states 
this condition, if not detected and corrected, could affect the correct 
operation of the TGB and possibly result in reduced control of the 
helicopter. Accordingly, the EASA AD requires a one-time inspection of 
the TGB housing recess and TGB oil duct housing, and depending on the 
findings, applicable investigative and corrective actions. The EASA AD 
also prohibits installation of a TGB unless it has passed the specified 
inspections.

Comments

    The FAA gave the public the opportunity to participate in 
developing this final rule. The following presents the comment received 
on the NPRM and the FAA's response to the comment.

Request

    A commenter asked who will be conducting the TGB inspections and 
how often the inspections will take place. A mechanic that meets the 
requirements of 14 CFR part 65 subpart D must perform the TGB 
inspections, which are required within 55 hours time-in-service or 5 
months, whichever occurs first.

FAA's Determination

    These helicopters have been approved by EASA and are approved for 
operation in the United States. Pursuant to the FAA's bilateral 
agreement with the European Union, EASA has notified the FAA of the 
unsafe condition described in its AD. The FAA is issuing this AD after 
evaluating all of the information provided by EASA and determining the 
unsafe condition exists and is likely to exist or develop on other 
helicopters of the same type designs and that air safety and the public 
interest require adopting the AD requirements as proposed except for 
updating the Costs of Compliance section due to an increase in the 
number of registered helicopters. These changes are consistent with the 
intent that was proposed in the NPRM for addressing the unsafe 
condition and do not add any additional burden upon the public than was 
already proposed in the NPRM.

Differences Between this AD and the EASA AD

    If required to remove a TGB, the EASA AD requires marking and 
returning the TGB to Airbus Helicopters, whereas this AD does not 
require marking or returning the TGB to Airbus Helicopters.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed one document that co-publishes four Airbus 
Helicopters Emergency Alert Service Bulletin (EASB) identification 
numbers: No. 65.00.09 for non FAA-type certificated military Model 
AS565MA, MB, MBe, SA, SB, and UB helicopters; No. 65.00.19 for Model 
AS365N1, N2, and N3 helicopters, and non FAA-type certificated military 
Model AS365F, Fi, K, and K2 helicopters; No. 65.06 for non FAA-type 
certificated military Model SA366GA helicopters; and No. 65A008 for 
Model EC155B and B1 helicopters, all Revision 0 and dated July 10, 
2019. EASB Nos. 65.00.19 and 65A008 are incorporated by reference in 
this AD. EASB Nos. 65.00.09 and 65.06 are not incorporated by reference 
in this AD.
    This service information specifies procedures, using an endoscope 
(borescope), to inspect the TGB housing recess for oil retention and 
the two T holes for visibility. If there is oil retention and the two T 
holes are not visible, this service information specifies removing the 
TGB control rod and inspecting for and removing any foreign objects in 
the TGB oil duct, and then repeating the TGB housing recess 
inspections. If there is oil retention and the two T holes are not 
visible after these additional inspections, the service information 
specifies marking the TGB as not fit for helicopter installation and 
returning the TGB to Airbus Helicopters. If there is no oil retention 
and the two T holes are visible after these additional inspections, the 
service information specifies removing any foreign objects in the TGB 
oil duct and inspecting for proper oil flow at the end of the BTP oil 
duct cover. If the oil does not flow properly, this service information 
specifies marking the TGB as not fit for helicopter installation and 
returning the TGB to Airbus Helicopters. If the oil flows properly, the 
service information specifies replacing the TGB control rod bearing 
with a new bearing.
    This service information also specifies procedures to close the 
filter plug cover with an airworthy O-ring, install the filter plug, 
replace a TGB, and perform a ground run-up. Additionally, this service 
information specifies procedures to perform the inspections on a non-
installed TGB.
    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.

[[Page 69133]]

Costs of Compliance

    The FAA estimates that this AD affects 51 helicopters of U.S. 
Registry. The FAA estimates that operators may incur the following 
costs in order to comply with this AD. Labor rates are estimated at $85 
per work-hour.
    Inspecting the TGB housing recess takes about 2 work-hours for an 
estimated cost of $170 per helicopter and $8,670 for the U.S. fleet.
    Inspecting for and removing any foreign objects takes a minimal 
amount of time for a nominal cost.
    Removing any oil retention and re-inspecting the TGB takes about 5 
work-hours for an estimated cost of $425 per helicopter.
    Inspecting for correct oil flow takes about 1 work-hour for an 
estimated cost of $85 per helicopter.
    Replacing the TGB control rod bearing takes about 8 work-hours and 
parts cost about $2,000 for an estimated replacement cost of $2,680 per 
bearing.
    Replacing a TGB takes about 40 work-hours and parts cost about 
$48,600 (overhauled) for an estimated replacement cost of $52,000 per 
TGB.

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.
    The FAA is 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) Will not affect intrastate aviation in Alaska, 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.

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):

2020-21-15 Airbus Helicopters: Amendment 39-21288; Docket No. FAA-
2020-0618; Product Identifier 2019-SW-064-AD.

(a) Applicability

    This AD applies to Airbus Helicopters Model AS-365N2, AS 365 N3, 
EC 155B, EC155B1, and SA-365N1 helicopters, certificated in any 
category.

(b) Unsafe Condition

    This AD defines the unsafe condition as obstruction of the oil 
duct of the tail rotor gearbox (TGB) control bearing. This condition 
could result in a lack of lubrication on the TGB control bearing, 
which could affect the correct operation of the TGB, and subsequent 
reduced control of the helicopter.

(c) Effective Date

    This AD becomes effective December 7, 2020.

(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) Within 55 hours time-in-service or 5 months, whichever 
occurs first: (i) Open the TGB oil filter plug cover (cover) 
identified as ``b'' in Detail ``A'' and Detail ``B'' in Figure 1 of 
Airbus Helicopters Emergency Alert Service Bulletin (EASB) No. 
65.00.19 or Airbus Helicopters EASB No. 65A008, both Revision 0 and 
dated July 10, 2019 (EASB 65.00.19 or EASB 65A008), as applicable to 
your model helicopter, by removing any lockwire, opening the cover 
(b), and removing the strainer (e) using a screwdriver. Remove the 
TGB oil filter plug (plug) identified as ``h'' in Detail ``B'' in 
Figure 1 of EASB 65.00.19 or EASB 65A008, as applicable to your 
model helicopter, by removing the sealing compound at the base of 
the plug (h), marking the base of the plug (h) and the TGB housing 
(c), and removing and cleaning the plug (h) and the exterior surface 
of the TGB housing (c) surrounding the plug (h) installation area.
    (ii) Using an adjustable or fixed head borescope with a 6 mm or 
larger diameter camera probe, inspect for operating oil (oil) 
retention and visibility of the two T holes in the TGB oil housing 
recess (housing recess) (towards the rear of the helicopter) 
identified as ``g'' in Section C-C in Figure 2 of EASB 65.00.19 or 
EASB 65A008, as applicable to your model helicopter.
    (A) If there is any oil retention in the housing recess (g) and 
the two T holes are not completely visible as shown in photo 1, in 
the Accomplishment Instructions, paragraph 3.B.2.b., of EASB 
65.00.19 or EASB 65A008, as applicable to your model helicopter, 
before further flight, remove the TGB control rod and inspect for 
and remove any foreign objects in the TGB oil duct (oil duct) 
identified as ``k'' in Detail ``D'' of Figure 2 of EASB 65.00.19 or 
EASB 65A008, as applicable to your model helicopter.
    (B) With all of the oil drained from the housing recess (g), 
inspect for oil retention and visibility of the two T holes in the 
housing recess (g) as required by paragraph (e)(1)(ii) of this AD.
    (1) If there is any oil retention in the housing recess (g) and 
the two T holes are not completely visible, before further flight, 
replace the TGB.
    (2) If there is no oil retention in the housing recess (g) and 
the two T holes are completely visible, before further flight:
    (i) Inspect for any foreign objects in the oil duct identified 
as ``k'' in Section EE of Figure 3 of EASB 65.00.19 or EASB 65A008, 
as applicable to your model helicopter. If there is any foreign 
object, before further flight, remove each foreign object.
    (ii) Inspect for oil flow at the end of the oil duct (k) BTP (q) 
cover by following the procedures in the second step through the 
sixth step, inclusive, of the Accomplishment Instructions, paragraph 
3.B.3.b., of EASB 65.00.19 or EASB 65A008, as applicable to your 
model helicopter.
    (iii) If the oil does not flow at the end of the oil duct (k) 
BTP (q) cover, before further flight, replace the TGB.
    (iv) If the oil flows at the end of the oil duct (k) BTP (q) 
cover, before further flight, remove from service the TGB control 
rod bearing.
    (2) As of the effective date of this AD, do not install a TGB on 
any helicopter unless, with the non-installed TGB in a level 
position using shims, the requirements of paragraph (e)(1) of this 
AD have been accomplished. Unless already done, installation of a 
new TGB control rod bearing is also required. Accomplishment 
Instructions, paragraph 3.B.6., of EASB 65.00.19 and EASB 65A008, as 
applicable to your model helicopter, contain information pertaining 
to inspecting a non-installed TGB. A TGB with a log card entry 
showing it has

[[Page 69134]]

passed the requirements in the Accomplishment Instructions, 
paragraph 3.B.6., of EASB 65.00.19 and EASB 65A008, as applicable to 
your model helicopter, is acceptable for compliance with this 
paragraph.

(f) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Rotorcraft Standards Branch, FAA, may approve 
AMOCs for this AD. Send your proposal to: Rao Edupuganti, Aviation 
Safety Engineer, Regulations and Policy Section, Rotorcraft 
Standards Branch, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; 
telephone 817-222-5110; email <a href="/cdn-cgi/l/email-protection#8fb6a2cedcd8a2c9dbd8a2cec2c0cca2ddeafefaeafcfbfccfe9eeeea1e8e0f9"><span class="__cf_email__" data-cfemail="a79e8ae6f4f08ae1f3f08ae6eae8e48af5c2d6d2c2d4d3d4e7c1c6c689c0c8d1">[email&#160;protected]</span></a>.
    (2) For operations conducted under a 14 CFR part 119 operating 
certificate or under 14 CFR part 91, subpart K, the FAA suggests 
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.

(g) Additional Information

    The subject of this AD is addressed in European Union Aviation 
Safety Agency (EASA) AD No. 2019-0165-E, dated July 12, 2019. You 
may view the EASA AD on the internet at <a href="https://www.regulations.gov">https://www.regulations.gov</a> 
in Docket No. FAA-2020-0618.

(h) Subject

    Joint Aircraft Service Component (JASC) Code: 62, Tail Rotor 
Gearbox.

(i) 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) Airbus Helicopters Emergency Alert Service Bulletin (EASB) 
No. 65.00.19, Revision 0, dated July 10, 2019.
    (ii) Airbus Helicopters EASB No. 65A008, Revision 0, dated July 
10, 2019.

    Note 1 to paragraph (i)(2): Airbus Helicopters EASB Nos. 
65.00.19 and 65A008, each Revision 0 and dated July 10, 2019, are 
co-published as one document along with Airbus Helicopters EASB Nos. 
65.00.09 and 65.06, each Revision 0 and dated July 10, 2019, which 
are not incorporated by reference in this AD.

    (3) For service information identified in this AD, contact 
Airbus Helicopters, 2701 N. Forum Drive, Grand Prairie, TX 75052; 
telephone 972-641-0000 or 800-232-0323; fax 972-641-3775; or at 
<a href="https://www.airbus.com/helicopters/services/technical-support.html">https://www.airbus.com/helicopters/services/technical-support.html</a>.
    (4) You may view this service information at the 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, email <a href="/cdn-cgi/l/email-protection#385e5d5c4a5d5f16545d5f59547856594a59165f574e"><span class="__cf_email__" data-cfemail="a6c0c3c2d4c3c188cac3c1c7cae6c8c7d4c788c1c9d0">[email&#160;protected]</span></a>, or go to: <a href="https://www.archives.gov/federal-register/cfr/ibr-locations.html">https://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.

    Issued on October 6, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2020-23977 Filed 10-30-20; 8:45 am]
BILLING CODE 4910-13-P

Source: Official FAA Source ↗

Retrieved: Apr 4, 2026

Rights: U.S. Government Public Domain

This site is not affiliated with or endorsed by the FAA. Always verify with official sources.