[Federal Register Volume 86, Number 107 (Monday, June 7, 2021)]
[Proposed Rules]
[Pages 30218-30221]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-11804]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0450; Project Identifier 2017-SW-100-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Helicopters Deutschland GmbH 
(AHD) Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for Airbus Helicopters Deutschland GmbH (AHD) Model MBB-BK 117 D-2 
helicopters. This proposed AD was prompted by the discovery that 
certain parts that are approved for installation on multiple helicopter 
models are life limited parts when installed on Model MBB-BK 117 D-2 
helicopters and some helicopter delivery documents excluded the life 
limit information. This proposed AD would require determining the total 
hours time-in-service (TIS) of a certain part-numbered rotor mast nut 
and re-identifying a certain part-numbered rotor mast nut. This 
proposed AD would also require establishing a life limit for a certain 
part-numbered rotor mast nut and helical gear support, and removing 
each part from service before reaching its life limit. Additionally, 
this proposed AD would require replacing a certain part-numbered main 
gearbox (MGB) with a not affected MGB as specified in a European 
Aviation Safety Agency (now European Union Aviation Safety Agency) 
(EASA) AD, which is proposed for incorporation by reference (IBR). The 
FAA is proposing this AD to address the unsafe condition on these 
products.

DATES: The FAA must receive comments on this proposed AD by July 22, 
2021.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: (202) 493-2251.
     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.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For material that is proposed for IBR in this AD, contact EASA, 
Konrad-Adenauer-Ufer 3, 50668 Cologne, Germany; telephone +49 221 8999 
000; email ADs@easa.europa.eu; internet www.easa.europa.eu. You may 
find this material on the EASA website at https://ad.easa.europa.eu. 
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 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 https://www.regulations.gov by searching for and locating 
Docket No. FAA-2021-0450.

Examining the AD Docket

    You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-
0450; 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 NPRM, any comments received, and other

[[Page 30219]]

information. The street address for Docket Operations is listed above. 
Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Rao Edupuganti, Aerospace Engineer, 
Dynamic Systems Section, Technical Innovation Policy Branch, Policy & 
Innovation Division, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; 
telephone (817) 222-5110; email rao.edupuganti@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under ADDRESSES. Include ``Docket No. FAA-2021-0450; Project Identifier 
2017-SW-100-AD'' at the beginning of your comments. The most helpful 
comments reference a specific portion of the proposal, explain the 
reason for any recommended change, and include supporting data. The FAA 
will consider all comments received by the closing date and may amend 
this proposal because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
https://www.regulations.gov, including any personal information you 
provide. The agency will also post a report summarizing each 
substantive verbal contact received about this proposal.

Confidential Business Information

    CBI is commercial or financial information that is both customarily 
and actually treated as private by its owner. Under the Freedom of 
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public 
disclosure. If your comments responsive to this NPRM contain commercial 
or financial information that is customarily treated as private, that 
you actually treat as private, and that is relevant or responsive to 
this NPRM, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and they will not be placed in the public 
docket of this NPRM. Submissions containing CBI should be sent to Rao 
Edupuganti, Aerospace Engineer, Dynamic Systems Section, Technical 
Innovation Policy Branch, Policy & Innovation Division, FAA, 10101 
Hillwood Pkwy., Fort Worth, TX 76177; telephone (817) 222-5110; email 
rao.edupuganti@faa.gov. Any commentary that the FAA receives that is 
not specifically designated as CBI will be placed in the public docket 
for this rulemaking.

Background

    EASA, which is the Technical Agent for the Member States of the 
European Union, has issued EASA AD 2017-0037, dated February 22, 2017 
(EASA AD 2017-0037), to correct an unsafe condition for Airbus 
Helicopters Deutschland GmbH (formerly Eurocopter Deutschland GmbH), 
Airbus Helicopters Inc. (formerly American Eurocopter LLC) Model MBB-BK 
117 D-2 and MBB-BK117 D-2m helicopters.
    This proposed AD was prompted by the discovery that certain parts 
that are approved for installation on multiple helicopter models are 
life limited parts when installed on Model MBB-BK 117 D-2 helicopters 
and some helicopter delivery documents excluded the life limit 
information. The FAA is proposing this AD to address an unsafe 
condition on these products. See EASA AD 2017-0037 for additional 
background information.

Related Service Information Under 1 CFR Part 51

    EASA AD 2017-0037 requires establishing a life limit for rotor mast 
nut part number (P/N) D632K1133-201 and helical gear support P/N 
D632K1113-201, and replacing these parts before exceeding their life 
limit. EASA AD 2017-0037 also requires replacing each rotor mast nut P/
N D632K1133-201 for which the hours time-in-service (TIS) are unknown 
and replacing certain part-numbered rotor mast nuts before accumulating 
3,708 hours TIS since first installation on a helicopter. EASA AD 2017-
0037 requires re-identifying each rotor mast nut P/N 117-12133-01 to P/
N D632K1133-201 by following the specified service information. EASA AD 
2017-0037 requires replacing any MGB P/N D632K1001-051 with serial 
number (S/N) D2-0001 up to D2-0108 inclusive, D2-0123, D2-0126, D2-
0127, or D2-0130 up to D2-0136 inclusive with a not affected MGB before 
the affected MGB accumulates 3,708 hours TIS. EASA AD 2017-0037 also 
prohibits installing an affected rotor mast nut or an affected MGB that 
has accumulated more than 3,708 hours TIS since first installation on a 
helicopter. Additionally, EASA AD 2017-0037 requires revising the 
Aircraft Maintenance Program (AMP).
    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.

Other Related Service Information

    The FAA reviewed Airbus Helicopters Alert Service Bulletin MBB-
BK117 D-2-63A-001, Revision 0, dated December 1, 2016 (ASB 63A-001), 
which is not incorporated by reference, which specifies procedures for 
re-identifying the rotor mast nut by using a vibrograph, crossing out 
the old P/N and marking the new P/N on the outer surface, engraving the 
letter ``A'' behind the S/N of each part, and updating the historical 
record and log card to confirm compliance with ASB 63A-001. ASB 63A-001 
also specifies during the next MGB overhaul, making an entry in the log 
card to confirm re-identification of the helical gear support, and 
annotating the S/N of the helical gear support.

FAA's Determination and Requirements of This Proposed AD

    These products have been approved by the aviation authority of 
another country, and are approved for operation in the United States. 
Pursuant to the bilateral agreement with the State of Design Authority, 
the FAA has been notified of the unsafe condition described in EASA AD 
2017-0037. The FAA is proposing this AD after evaluating all the 
relevant information and determining the unsafe condition described 
previously is likely to exist or develop in other products of the same 
type design.

Proposed AD Requirements

    This proposed AD would require accomplishing the actions specified 
in EASA AD 2017-0037, described previously, as incorporated by 
reference, except for any differences identified as exceptions in the 
regulatory text of this proposed AD and except as discussed under 
``Differences Between this Proposed AD and the EASA AD.''

Explanation of Required Compliance Information

    In the FAA's ongoing efforts to improve the efficiency of the AD 
process, the FAA initially worked with Airbus and EASA to develop a 
process to use certain EASA ADs as the primary source of information 
for compliance with requirements for corresponding FAA ADs. The FAA has 
since coordinated with other manufacturers and civil aviation 
authorities (CAAs) to use this process. As a result, EASA AD 2017-0037 
will be incorporated by reference in the FAA final rule. This proposed 
AD would, therefore, require compliance with EASA AD 2017-0037

[[Page 30220]]

in its entirety, through that incorporation, except for any differences 
identified as exceptions in the regulatory text of this proposed AD. 
Using common terms that are the same as the heading of a particular 
section in the EASA AD does not mean that operators need comply only 
with that section. For example, where the AD requirement refers to 
``all required actions and compliance times,'' compliance with this AD 
requirement is not limited to the section titled ``Required Action(s) 
and Compliance Time(s)'' in the EASA AD. Service information specified 
in EASA AD 2017-0037 that is required for compliance with EASA AD 2017-
0037 will be available on the internet at https://www.regulations.gov 
by searching for and locating Docket No. FAA-2021-0450 after the FAA 
final rule is published.

Differences Between This Proposed AD and the EASA AD

    EASA AD 2017-0037 applies to Model MBB-BK117 D-2 and D2m 
helicopters, whereas this proposed AD would only apply to Model MBB-
BK117 D-2 helicopters because Model D-2m is not FAA type-certificated. 
If the total hours TIS for an affected rotor mast nut cannot be 
determined, this proposed AD would require removing the rotor mast nut 
from service before further flight, whereas EASA AD 2017-0037 does not 
contain this requirement. EASA AD 2017-0037 requires using a vibrograph 
to re-identify certain rotor mast nuts, whereas this proposed AD would 
require using a vibro etch instead. EASA AD 2017-0037 requires 
replacing certain parts, whereas this proposed AD would require 
removing certain parts from service instead. EASA AD 2017-0037 requires 
revising the AMP, whereas this proposed AD would not.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 30 helicopters of U.S. Registry. Labor rates are estimated at 
$85 per work-hour. Based on these numbers, the FAA estimates the 
following costs to comply with this proposed AD.
    Determining the total hours TIS on an affected rotor mast nut would 
take about 1 work-hour for an estimated cost of $85 per helicopter and 
$2,550 for the U.S. fleet.
    Re-identifying a rotor mast nut would take about 1.5 work-hours for 
an estimated cost of $128 per rotor mast nut.
    Replacing a rotor mast nut would take about 6 work-hours and parts 
would cost about $5,351 for an estimated cost of $5,861 per rotor mast 
nut.
    Replacing a main gearbox, which includes replacing the helical gear 
support, would take about 42 work-hours and parts would cost about 
$295,000 (overhauled) for an estimated cost of $298,570.

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 products identified in this rulemaking action.

Regulatory Findings

    The FAA determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Would not affect intrastate aviation in Alaska, and
    (3) Would 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 Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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:

Airbus Helicopters Deutschland GmbH (AHD): Docket No. FAA-2021-0450; 
Project Identifier 2017-SW-100-AD.

(a) Comments Due Date

    The FAA must receive comments by July 22, 2021.

(b) Affected Airworthiness Directives (ADs)

    None.

(c) Applicability

    This AD applies to Airbus Helicopters Deutschland GmbH (AHD) 
Model MBB-BK 117 D-2 helicopters, certificated in any category, with 
an affected main gearbox or affected rotor mast nut as identified in 
Note 1 of European Aviation Safety Agency (now European Union 
Aviation Safety Agency) (EASA) AD 2017-0037, dated February 22, 2017 
(EASA AD 2017-0037) installed.

(d) Subject

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

(e) Unsafe Condition

    This proposed AD was prompted by the discovery that certain 
parts that are approved for installation on multiple helicopter 
models are life limited parts when installed on Model MBB-BK 117 D-2 
helicopters and some helicopter delivery documents excluded the life 
limit information. The FAA is issuing this AD to prevent certain 
parts from remaining in service beyond their fatigue life. The 
unsafe condition, if not addressed, could result in failure of the 
part and 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 2017-0037.

(h) Exceptions to EASA AD 2017-0037

    (1) Where EASA AD 2017-0037 refers to its effective date, this 
AD requires using the effective date of this AD.
    (2) Where EASA AD 2017-0037 refers to flight hours (FH), this AD 
requires using hours time-in-service (TIS).
    (3) Where paragraph (1) of EASA AD 2017-0037 requires 
determining the FH (total hours TIS) accumulated by the affected 
rotor mast nut since first installation on a helicopter, this AD 
requires removing the rotor mast nut from service before further

[[Page 30221]]

flight if the total hours TIS cannot be determined.
    (4) Where the service information referenced in Note 3 of EASA 
AD 2017-0037 specifies to use a vibrograph to mark the new part 
number, this AD requires using a vibro etch.
    (5) Where paragraph (4) of EASA AD 2017-0037 requires replacing 
each affected rotor mast nut with a not affected rotor mast nut 
before exceeding 3,708 FH (total hours TIS) since first installation 
on a helicopter, this AD requires removing each affected rotor mast 
nut from service before accumulating 3,708 total hours TIS.
    (6) Where paragraph (6) of EASA AD 2017-0037 requires replacing 
each part as identified in Table 2 of EASA AD 2017-0037 before 
exceeding the FH (total hours TIS) limit, this AD requires removing 
each part from service before exceeding the total hours TIS limit.
    (7) Paragraph (7) of EASA AD 2017-0037 does not apply to this 
AD.
    (8) The ``Remarks'' section of EASA AD 2017-0037 does not apply 
to this AD.

(i) 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 (j)(2) of 
this AD. Information may be emailed to: 9-AVS-AIR-730-AMOC@faa.gov.
    (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.

(j) Related Information

    (1) For EASA AD 2017-0037, contact EASA, Konrad-Adenauer-Ufer 3, 
50668 Cologne, Germany; telephone +49 221 8999 000; email 
ADs@easa.europa.eu; internet www.easa.europa.eu. You may find this 
EASA AD on the EASA website at https://ad.easa.europa.eu. 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 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 https://www.regulations.gov by searching 
for and locating Docket No. FAA-2021-0450.
    (2) For more information about this AD, contact Rao Edupuganti, 
Aerospace Engineer, Dynamic Systems Section, Technical Innovation 
Policy Branch, Policy & Innovation Division, FAA, 10101 Hillwood 
Pkwy., Fort Worth, TX 76177; telephone (817) 222-5110; email 
rao.edupuganti@faa.gov.

    Issued on May 27, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-11804 Filed 6-4-21; 8:45 am]
BILLING CODE 4910-13-P


