DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-1126; Product Identifier 2017-SW-125-AD; Amendment
39-19587; AD 2019-05-05]
RIN 2120-AA64

Airworthiness Directives; Airbus Helicopters Deutschland GmbH
(Previously Eurocopter Deutschland GmbH) Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are superseding Airworthiness Directive (AD) 97-26-03 for
Eurocopter Deutschland GmbH Model MBB-BK 117 A-1, MBB-BK 117 A-3, MBB-
BK 117 A-4, MBB-BK 117 B-1, MBB-BK 117 B-2, and MBB-BK 117 C-1
helicopters. AD 97-26-03 required visual inspections for cracks in the
ribbed area of the main rotor (M/R) mast flange (flange). Since we
issued AD 97-26-03, we have determined that a certain reinforced M/R
mast is not affected by the unsafe condition. This new AD retains the
requirements of AD 97-26-03 and removes a certain M/R mast from the
applicability. The actions of this AD are intended to address an unsafe
condition on these products.

DATES: This AD is effective April 17, 2019.
The Director of the Federal Register approved the incorporation by
reference of a certain document listed in this AD as of April 17, 2019.

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 http://www.helicopters.airbus.com/website/en/ref/Technical-Support_73.html.
You may review this 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 http://www.regulations.gov by searching for and
locating Docket No. FAA-2017-1126.

Examining the AD Docket

You may examine the AD docket on the internet at http://www.regulations.gov
in Docket No. FAA-2017-1126; 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 address for Docket Operations (phone: 800-647-5527) is
Docket Operations, 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: 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 matthew.fuller@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to remove AD 97-26-03, Amendment 39-10246 (62 FR 65750,
December 16, 1997) (AD 97-26-03) and add a new AD. AD 97-26-03 applied
to Eurocopter Deutschland GmbH (now Airbus Helicopters Deutschland
GmbH) Model MBB-BK 117 A-1, MBB-BK 117 A-3, MBB-BK 117 A-4, MBB-BK 117
B-1, MBB-BK 117 B-2, and MBB-BK 117 C-1 helicopters. AD 97-26-03
required visual inspections for cracks in the ribbed area of the M/R
flange and replacing the M/R mast if a crack is found.
The NPRM published in the Federal Register on September 13, 2018
(83 FR 46426). The NPRM was prompted by EASA AD No. 2017-0193, dated
September 29, 2017 (EASA AD 2017-0193), issued by EASA, which is the
Technical Agent for the member States of the European Union. EASA AD
2017-0193 superseded AD 97-276, effective September 25, 1997, issued by
Luftfahrt-Bundesamt (LBA), which is the airworthiness authority for
Germany, to correct an unsafe condition for Eurocopter Deutschland GmbH
Model MBB-BK 117 A-1, MBB-BK 117 A-3, MBB-BK 117 A-4, MBB-BK 117 B-1,
MBB-BK 117 B-2, and MBB-BK 117 C-1 helicopters. EASA advises that
reinforced M/R mast part number (P/N) 4639 305 095, which is part of M/
R mast assembly P/N 4639 205 016, is not affected by the unsafe
condition. EASA AD 2017-0193 retains the repetitive inspection
requirements of the LBA AD but only for helicopters with M/R mast P/N
4639 305 002.
Since we issued AD 97-26-03, Eurocopter Deutschland GmbH
Helicopters changed its name to Airbus
Helicopters Deutschland GmbH. This AD reflects that change and updates
the contact information to obtain service documentation. Additionally,
the FAA's Aircraft Certification Service has changed its organizational
structure. The new structure replaces product directorates with
functional divisions. We have revised some of the office titles and
nomenclature throughout this AD to reflect the new organizational
changes. Additional information about the new structure can be found in
the Notice published on July 25, 2017 (82 FR 34564).

Comments

We gave the public the opportunity to participate in developing
this AD, but we did not receive any comments on the NPRM.

FAA's Determination

These helicopters have been approved by the aviation authority of
Germany and are approved for operation in the United States. Pursuant
to our bilateral agreement with Germany, EASA, its technical
representative, has notified us of the unsafe condition described in
its AD. We have reviewed the relevant information and determined that
an 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

The EASA AD requires contacting Airbus Helicopters if a crack is
found on the flange for applicable instructions, whereas this AD
requires replacing the M/R mast with an airworthy M/R mast before
further flight.

Related Service Information Under 1 CFR Part 51

We reviewed Airbus Helicopters Alert Service Bulletin No. ASB MBB-
BK117-10-114, Revision 1, dated July 28, 2017. This service information
specifies visually inspecting the area of the holes on the underside of
the flange for cracks, especially in the ribbed area between the holes,
and if cracks are found, contacting Airbus Helicopters Deutschland GmbH
before further flight for advice on how to proceed. This service
information applies to helicopters with M/R mast assembly P/N 4639 205 011.
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.

Other Related Service Information

We also reviewed Eurocopter Alert Service Bulletin No. ASB MBB-
BK117-10-114, dated August 27, 1997, which specifies visually
inspecting the area of the holes on the underside of the flange for
cracks, especially in the ribbed area between the holes, and if cracks
are found, contacting Eurocopter Helicopter Deutschland GmbH before
further flight for advice on how to proceed. This service information
applies to helicopters with M/R mast assembly P/N 4639 205 011 or 4639
205 016.

Costs of Compliance

We estimate that this AD affects 62 helicopters of U.S. Registry.
We estimate that operators may incur the following costs in order to
comply with this AD. Labor costs are estimated at $85 per work-hour.
Visually inspecting the flange for a crack requires 0.25 work-hour
for an estimated cost of about $21 per helicopter and $1,302 for the
U.S. fleet per inspection cycle. Replacing the M/R mast requires 10
work-hours and parts cost $50,000 for an estimated cost of $50,850 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 products identified in this
rulemaking action.

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 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 a regulatory distinction is required, 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.

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

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]

2. The FAA amends Sec. 39.13 by removing Airworthiness Directive (AD)
97-26-03, Amendment 39-10246 (62 FR 65750, December 16, 1997), and
adding the following new AD: