AD 2021-10-14

final rule

Airworthiness Directives; Airbus Helicopters Deutschland GmbH Helicopters

AD Number
2021-10-14
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2021-0143
FR Citation
86 FR 27268

Applicability

TypeManufacturerModelDetails
aircraft Airbus Various Airworthiness Directives; Airbus Helicopters Deutschland GmbH Helicopters
aircraft Aviat Various Airworthiness Directives; Airbus Helicopters Deutschland GmbH Helicopters

Unsafe Condition

aging of the elastomeric material in a tension torsion strap (TT-strap) could affect the structural characteristics of the TT-strap, leading to premature failure of a TT-strap, resulting in loss of control of the helicopter.

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

Required Actions

replace certain TT-straps with serviceable parts and implementation of a new storage life limit for TT-straps, as specified in an EASA AD.

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

Compliance Time

Within 50 flight hours

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

Affected Aircraft

Airbus Helicopters Deutschland GmbH Model BO-105A, BO-105C, BO-105S, and BO-105LS A-3 helicopters, certificated in any category, equipped with a tension torsion strap (TT-strap) as identified in EASA AD 2019-0024.

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 certain Airbus Helicopters Deutschland GmbH Model BO-105A, BO-105C, BO- 105S, and BO-105LS A-3 helicopters. This AD was prompted by the FAA's determination that aging of the elastomeric material in a tension torsion strap (TT-strap) could affect the structural characteristics of the TT-strap. This AD requires replacement of certain TT-straps with serviceable parts and implementation of a new storage life limit for TT-straps, as specified in a European Aviation Safety Agency (now European Union Aviation Safety Agency) (EASA) AD, which is incorporated by reference. The FAA is issuing this AD to address the unsafe condition on these products.

Applicability Source Text

Show captured applicability text from the source AD
(c) Applicability

    This AD applies to Airbus Helicopters Deutschland GmbH Model BO-
105A, BO-105C, BO-105S, and BO-105LS A-3 helicopters, certificated 
in any category, equipped with a tension torsion strap (TT-strap) as 
identified in European Aviation Safety Agency (now European Union 
Aviation Safety Agency) (EASA) AD 2019-0024, dated February 4, 2019 
(EASA AD 2019-0024).

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 86, Number 96 (Thursday, May 20, 2021)]
[Rules and Regulations]
[Pages 27268-27271]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2021-10605]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0143; Product Identifier 2019-SW-024-AD; Amendment 
39-21547; AD 2021-10-14]
RIN 2120-AA64


Airworthiness Directives; Airbus Helicopters Deutschland GmbH 
Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain Airbus Helicopters Deutschland GmbH Model BO-105A, BO-105C, BO-
105S, and BO-105LS A-3 helicopters. This AD was prompted by the FAA's 
determination that aging of the elastomeric material in a tension 
torsion strap (TT-strap) could affect the structural characteristics of 
the TT-strap. This AD requires replacement of certain TT-straps with 
serviceable parts and implementation of a new storage life limit for 
TT-straps, as specified in a European Aviation Safety Agency (now 
European Union Aviation Safety Agency) (EASA) AD, which is incorporated 
by reference. The FAA is issuing this AD to address the unsafe 
condition on these products.

DATES: This AD is effective June 24, 2021.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of June 24, 
2021.

ADDRESSES: For material incorporated by reference (IBR) in this AD, 
contact the EASA, Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; 
telephone +49 221 8999 000; email <a href="/cdn-cgi/l/email-protection#3475704774515547551a5141465b44551a5141"><span class="__cf_email__" data-cfemail="9adbdee9dafffbe9fbb4ffefe8f5eafbb4ffef">[email&#160;protected]</span></a>; internet 
www.easa.europa.eu. You may find this material on the EASA website at 
<a href="https://ad.easa.europa.eu">https://ad.easa.europa.eu</a>. You may view this material at the FAA, 
Office of the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., 
Room 6N-321, Fort Worth, TX 76177. For information

[[Page 27269]]

on the availability of this material at the FAA, call 817-222-5110. It 
is also available in 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-2021-
0143.

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-2021-
0143; 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 final rule, any comments received, and other information. The 
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: Blaine Williams, Aviation Safety 
Engineer, Los Angeles ACO Branch, 3960 Paramount Boulevard, Lakewood, 
CA 90712 4137; telephone 562-627-5371; email <a href="/cdn-cgi/l/email-protection#fe9c929f97909bd089979292979f938dbe989f9fd0999188"><span class="__cf_email__" data-cfemail="3a58565b53545f144d535656535b57497a5c5b5b145d554c">[email&#160;protected]</span></a>.

SUPPLEMENTARY INFORMATION:

Background

    The EASA, which is the Technical Agent for the Member States of the 
European Union, has issued EASA AD 2019-0024, dated February 4, 2019 
(EASA AD 2019-0024) (also referred to as the Mandatory Continuing 
Airworthiness Information, or the MCAI), to correct an unsafe condition 
for certain Airbus Helicopters Deutschland GmbH Model BO-105A, BO-105C, 
BO-105D, BO-105S, and BO-105LS A-3 helicopters. Model BO-105D 
helicopters are not certificated by the FAA and are not included on the 
U.S. type certificate data sheet; this AD therefore does not include 
those helicopters in the applicability.
    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to certain Airbus 
Helicopters Deutschland GmbH Model BO-105A, BO-105C, BO-105S, and BO-
105LS A-3 helicopters. The NPRM published in the Federal Register on 
March 12, 2021 (86 FR 14023). The NPRM was prompted by the FAA's 
determination that aging of the elastomeric material in a tension TT-
strap could affect the structural characteristics of the TT-strap. The 
NPRM proposed to require replacement of certain TT-straps with 
serviceable parts and implementation of a new storage life limit for 
TT-straps, as specified in an EASA AD.
    The FAA is issuing this AD to address aging of the elastomeric 
material in a TT-strap, which could lead to premature failure of a TT-
strap, resulting in loss of control of the helicopter. See the MCAI for 
additional background information.

Discussion of Final Airworthiness Directive

Comments

    The FAA gave the public the opportunity to participate in 
developing this final rule. The FAA received no comments on the NPRM or 
on the determination of the cost to the public.

Conclusion

    The FAA reviewed the relevant data and determined that air safety 
and the public interest require adopting this final rule as proposed, 
except for minor editorial changes. The FAA has determined that these 
minor changes:
    <bullet> Are consistent with the intent that was proposed in the 
NPRM for addressing the unsafe condition; and
    <bullet> Do not add any additional burden upon the public than was 
already proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

    EASA AD 2019-0024 specifies procedures for replacing certain TT-
straps with serviceable parts and requires a storage life limit for TT-
straps. This material 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.

Differences Between This AD and the MCAI

    Although EASA AD 2019-0024 does not specify a life limit for the 
Lord TT-Straps part number (P/N) J17322-1 and P/N 117-14111, this AD 
does specify a life limit for those parts.
    Where EASA AD 2019-0024 specifies that installation of a Lord TT-
Strap is allowed provided the first flight of that helicopter after 
that installation is accomplished before the storage life of that Lord 
TT-Strap exceeds 5 years, for this AD, the installation of a Lord TT-
Strap is allowed provided the first flight of that helicopter after 
that installation is accomplished before 5 years since the TT-strap's 
date of manufacture.
    Where EASA AD 2019-0024 defines ``serviceable part'' as a Lord TT-
Strap having a storage life not exceeding 5 years, for this AD, a 
serviceable part is Lord TT-straps P/N J17322-1 and P/N 117-14111 
having less than 5 years since that TT-strap's date of manufacture.
    Where EASA AD 2019-0024 specifies that the ``cure date'' of a TT-
Strap can be determined using the information provided in the 
applicable service information specified in EASA AD 2019-0024, or 
contacting Airbus Helicopters for applicable instructions, for this AD, 
the option of contacting Airbus Helicopters is not required.

Costs of Compliance

    The FAA estimates that this AD affects 61 helicopters of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                      Estimated Costs for Required Actions
----------------------------------------------------------------------------------------------------------------
              Labor cost                      Parts cost            Cost per product      Cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
4 work-hours x $85 per hour = $340...  Up to $4,800...........  Up to $5,140...........  Up to $313,540.
----------------------------------------------------------------------------------------------------------------

    According to the manufacturer, some or all of the costs of this AD 
may be covered under warranty, thereby reducing the cost impact on 
affected operators. The FAA does not control warranty coverage for 
affected operators. As a result, the FAA has included all known costs 
in the 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.
    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

[[Page 27270]]

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.

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.

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:

2021-10-14 Airbus Helicopters Deutschland GmbH: Amendment 39-21547; 
Docket No. FAA-2021-0143; Product Identifier 2019-SW-024-AD.

(a) Effective Date

    This airworthiness directive (AD) is effective June 24, 2021.

(b) Affected ADs

    This AD affects AD 2016-25-14, Amendment 39-18740 (81 FR 94944, 
December 27, 2016) (AD 2016-25-14).

(c) Applicability

    This AD applies to Airbus Helicopters Deutschland GmbH Model BO-
105A, BO-105C, BO-105S, and BO-105LS A-3 helicopters, certificated 
in any category, equipped with a tension torsion strap (TT-strap) as 
identified in European Aviation Safety Agency (now European Union 
Aviation Safety Agency) (EASA) AD 2019-0024, dated February 4, 2019 
(EASA AD 2019-0024).

(d) Subject

    Joint Aircraft System Component (JASC) Code 6200, Main Rotor 
System.

(e) Reason

    This AD was prompted by the FAA's determination that aging of 
the elastomeric material in a TT-strap could affect the structural 
characteristics of the TT-strap. The FAA is issuing this AD to 
address aging of the elastomeric material in a TT-strap, which could 
lead to premature failure of a TT-strap, resulting in loss of 
control of the helicopter.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Requirements

    Except as specified in paragraph (h) of this AD: Comply with all 
required actions and compliance times specified in, and in 
accordance with, EASA AD 2019-0024.

(h) Exceptions to EASA AD 2019-0024

    (1) Where EASA AD 2019-0024 refers to its effective date, this 
AD requires using the effective date of this AD.
    (2) The ``Remarks'' section of EASA AD 2019-0024 does not apply 
to this AD.
    (3) Where EASA AD 2019-0024 and the service information 
referenced in EASA AD 2019-0024 specify contacting Airbus 
Helicopters Deutschland if the storage time for a TT-strap is equal 
to or greater than 5 years, this AD requires repair using a method 
approved by the Manager, International Validation Branch, FAA. For a 
repair method to be approved by the Manager, International 
Validation Branch, as required by this paragraph, the Manager's 
approval letter must specifically refer to this AD.
    (4) Although the service information referenced in EASA AD 2019-
0024 specifies to scrap certain parts, this AD requires removing 
those parts from service instead.
    (5) Where paragraph (1) of EASA AD 2019-0024 specifies to 
replace each Lord TT-Strap and Bendix TT-Strap ``in accordance with 
the instructions of the applicable ASB,'' the replacement must be 
done using FAA-approved procedures.
    (6) Where EASA AD 2019-0024 refers to the airworthiness 
limitations items of the airworthiness limitations section of the 
aircraft maintenance manual (AMM) for the definition of service life 
limit (SLL), this AD requires using the life limits specified in 
paragraphs (h)(6)(i) through (iii) of this AD, as applicable:
    (i) For Bendix TT-Strap part number (P/N) 2604067 and P/N 117-
14110: Before 10 years or 40,000 flight cycles on the part, 
whichever occurs first.
    (ii) For Bendix TT-Strap P/N 2602559 and P/N 2606576: Before 10 
years, 2,400 hours time-in-service, or 40,000 flight cycles on the 
part, whichever occurs first.
    (iii) For Lord TT-Strap P/N J17322-1 and P/N 117-14111: Before 
12 years or 40,000 flight cycles on the part, whichever occurs 
first.
    (7) Where paragraph (3) of EASA AD 2019-0024 specifies that 
installation of a Lord TT-Strap is allowed provided the first flight 
of that helicopter after that installation is accomplished before 
the storage life of that Lord TT-Strap exceeds 5 years, for this AD, 
the installation of a Lord TT-Strap is allowed provided the first 
flight of that helicopter after that installation is accomplished 
before 5 years since the TT-strap's date of manufacture.
    (8) Where EASA AD 2019-0024 defines ``serviceable part'' as a 
Lord TT-Strap having a storage life not exceeding 5 years, for this 
AD, a serviceable part is Lord TT-straps P/N J17322-1 and P/N 117-
14111 having less than 5 years since that TT-strap's date of 
manufacture.
    (9) Where EASA AD 2019-0024 specifies that the ``cure date'' of 
a TT-Strap can be determined using the information provided in the 
applicable service information specified in EASA AD 2019-0024, or 
contacting Airbus Helicopters for applicable instructions, for this 
AD, the option of contacting Airbus Helicopters is not required.

(i) Repetitive Replacement

    After accomplishing the replacement specified in paragraph (1) 
of EASA AD 2019-0024, thereafter, replace the Lord TT-straps P/N 
J17322-1 and P/N 117-14111, at intervals not to exceed: Before 12 
years or 40,000 flight cycles on the part, whichever occurs first.

(j) Terminating Action for AD 2016-25-14

    For Model B0-105LS A-3 helicopters: After accomplishing the 
replacement specified in paragraph (1) of EASA AD 2019-0024 all of 
the actions required by AD 2016-15-14 are terminated for that 
helicopter only.

(k) Special Flight Permit

    Special flight permits, as described in 14 CFR 21.197 and 
21.199, are not allowed.

(l) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, International Validation Branch, FAA, has the 
authority to approve AMOCs for this AD, if requested using the 
procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, 
send your request to your principal inspector or local Flight 
Standards District Office, as appropriate. If sending information 
directly to the manager of the International Validation Branch, send 
it to the attention of the person identified in paragraph (m) of 
this AD. Information may be emailed to: <a href="/cdn-cgi/l/email-protection#ebd2c6aabdb8c6aaa2b9c6dcd8dbc6aaa6a4a8ab8d8a8ac58c849d"><span class="__cf_email__" data-cfemail="3d04107c6b6e107c746f100a0e0d107c70727e7d5b5c5c135a524b">[email&#160;protected]</span></a>.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(m) Related Information

    For more information about this AD, contact Blaine Williams, 
Aviation Safety Engineer, Los Angeles ACO Branch, 3960 Paramount 
Boulevard, Lakewood, CA 90712 4137; telephone 562-627-5371; email 
<a href="/cdn-cgi/l/email-protection#4c2e202d252229623b252020252d213f0c2a2d2d622b233a"><span class="__cf_email__" data-cfemail="76141a171f181358011f1a1a1f171b053610171758111900">[email&#160;protected]</span></a>.

[[Page 27271]]

(n) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) 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 this AD specifies otherwise.
    (i) European Aviation Safety Agency (EASA) AD 2019-0024, dated 
February 4, 2019.
    (ii) [Reserved]
    (3) For EASA AD 2019-0024, contact the EASA, Konrad-Adenauer-
Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999 000; email 
<a href="/cdn-cgi/l/email-protection#fbbabf88bb9e9a889ad59e8e89948b9ad59e8e"><span class="__cf_email__" data-cfemail="5e1f1a2d1e3b3f2d3f703b2b2c312e3f703b2b">[email&#160;protected]</span></a>; Internet www.easa.europa.eu. You may find this 
EASA AD on the EASA website at <a href="https://ad.easa.europa.eu">https://ad.easa.europa.eu</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. This material may be 
found in 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-
2021-0143.
    (5) You may view this material 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#7b1d1e1f091e1c55171e1c1a173b151a091a551c140d"><span class="__cf_email__" data-cfemail="fa9c9f9e889f9dd4969f9d9b96ba949b889bd49d958c">[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 April 30, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-10605 Filed 5-19-21; 8:45 am]
BILLING CODE 4910-13-P

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