AD 2013-12-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Aviat | Various | Airworthiness Directives; Eurocopter Deutschland (Eurocopter) Helicopters |
Unsafe Condition
Separation of the air conditioning drive pulley from the rotor brake disc on the tail rotor driveshaft, which could damage the T/R driveshaft and result in loss of control of the helicopter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Before further flight, inspect the pulley for looseness and proper lockwire installation. Thereafter, inspect the pulley every 10 hours time-in-service (TIS) for looseness and proper lockwire. Within 25 hours TIS, remove the pulley, inspect bolts and mounting holes with a 10X or higher magnifying glass, and reinstall the pulley. Replace the pulley if damage or distortion is found.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight, and at intervals not exceeding 10 hours TIS for repetitive inspections; within 25 hours TIS for removal, inspection, and reinstallation of the pulley.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Eurocopter Model MBB-BK117 A-3, MBB-BK117 A-4, MBB-BK117 B-1, and MBB-BK117 C-2 helicopters with a Metro Aviation vapor-cycle air conditioning kit installed in accordance with Supplemental Type Certificate No. SH3880SW.
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 Eurocopter Model MBB-BK117 A-3, MBB-BK117 A-4, MBB-BK117 B-1, and MBB- BK117 C-2 helicopters with a Metro Aviation (Metro) vapor-cycle air conditioning kit installed in accordance with Supplemental Type Certificate (STC) No. SH3880SW. This AD requires repetitively inspecting the air conditioning drive pulley (pulley) for looseness and properly installed lockwire, and also requires reinstalling the pulley. This AD is prompted by two reports of the pulley detaching from the rotor brake disc on the tail rotor (T/R) driveshaft. These actions are intended to prevent separation of the pulley, damage to the T/R driveshaft, and subsequent loss of control of the helicopter.
Document Text
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[Federal Register Volume 78, Number 131 (Tuesday, July 9, 2013)]
[Rules and Regulations]
[Pages 40956-40958]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2013-16388]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2013-0520; Directorate Identifier 2013-SW-027-AD;
Amendment 39-17484; AD 2013-12-06]
RIN 2120-AA64
Airworthiness Directives; Eurocopter Deutschland (Eurocopter)
Helicopters
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Final rule; request for comments.
-----------------------------------------------------------------------
SUMMARY: We are adopting a new airworthiness directive (AD) for
Eurocopter Model MBB-BK117 A-3, MBB-BK117 A-4, MBB-BK117 B-1, and MBB-
BK117 C-2 helicopters with a Metro Aviation (Metro) vapor-cycle air
conditioning kit installed in accordance with Supplemental Type
Certificate (STC) No. SH3880SW. This AD requires repetitively
inspecting the air conditioning drive pulley (pulley) for looseness and
properly installed lockwire, and also requires reinstalling the pulley.
This AD is prompted by two reports of the pulley detaching from the
rotor brake disc on the tail rotor (T/R) driveshaft. These actions are
intended to prevent separation of the pulley, damage to the T/R
driveshaft, and subsequent loss of control of the helicopter.
DATES: This AD becomes effective July 24, 2013.
We must receive comments on this AD by September 9, 2013.
ADDRESSES: You may send comments by any of the following methods:
<bullet> Federal eRulemaking Docket: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a>. Follow the online instructions for sending your
comments electronically.
<bullet> Fax: 202-493-2251.
<bullet> Mail: Send comments to the U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590-0001.
<bullet> Hand Delivery: Deliver to the ``Mail'' address between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
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> or in person at the Docket Operations Office
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains this AD, the STC, the economic
evaluation, any comments received, and other information. The street
address for the Docket Operations Office (telephone 800-647-5527) is in
the ADDRESSES section. Comments will be available in the AD docket
shortly after receipt.
For service information identified in this AD, contact Metro
Aviation, Inc., 1214 Hawn Ave, Shreveport, LA 71107; phone: (318) 222-
5529; Web site: <a href="http://metroproductsupport.com">metroproductsupport.com</a>. You may review the referenced
service information at the FAA, Office of the Regional Counsel,
Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas
76137.
FOR FURTHER INFORMATION CONTACT: Martin Crane, Aviation Safety
Engineer, Rotorcraft Certification Office, Rotorcraft Directorate, FAA,
2601 Meacham Blvd., Fort Worth, Texas 76137; telephone (817) 222-5056;
email <a href="/cdn-cgi/l/email-protection#a0978de1f6f38de1f3f78d919790e0c6c1c18ec7cfd6"><span class="__cf_email__" data-cfemail="c7f0ea869194ea869490eaf6f0f787a1a6a6e9a0a8b1">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Comments Invited
This AD is a final rule that involves requirements affecting flight
safety, and we did not provide you with notice and an opportunity to
provide your comments prior to it becoming effective. However, we
invite you to participate in this rulemaking by submitting written
comments, data, or views. We also invite comments relating to the
economic, environmental, energy, or federalism impacts that resulted
from adopting this AD. The most helpful comments reference a specific
portion of the AD, explain the reason for any recommended change, and
include supporting data. To ensure the docket does not contain
duplicate comments,
[[Page 40957]]
commenters should send only one copy of written comments, or if
comments are filed electronically, commenters should submit them only
one time. We will file in the docket all comments that we receive, as
well as a report summarizing each substantive public contact with FAA
personnel concerning this rulemaking during the comment period. We will
consider all the comments we receive and may conduct additional
rulemaking based on those comments.
Discussion
STC No. SH3880SW approves the installation of the Metro vapor-cycle
air conditioning kit on Eurocopter Model MBB-BK117 A-3, MBB-BK117 A-4,
MBB-BK117 B-1, and MBB-BK117 C-2 helicopters. The air conditioning
compressor is driven by a pulley attached to the rotor brake disc. We
received a report of a recent incident where the fasteners attaching
the air conditioning compressor pulley to the rotor brake disc lost
torque and allowed the pulley to separate. After the helicopter landed
without incident, the pulley was discovered loose, rotating freely on,
and causing damage to the T/R driveshaft. A prior incident in 2008
occurred where the pulley mount bolts sheared, resulting in the pulley
detaching from the rotor brake disc. Separation of the pulley from the
rotor brake disc could damage the T/R driveshaft, resulting in
subsequent loss of control of the helicopter.
FAA's Determination
We are issuing this AD because we evaluated all information
provided by Metro and determined the unsafe condition exists and is
likely to exist or develop on other helicopters of these same type
designs.
Related Service Information
We reviewed Metro Alert Service Bulletin No. MA145-21A-003,
Revision A, dated April 26, 2013 (ASB MA145-21A-003), which describes
procedures to inspect the pulley for properly installed lockwire, and
for removing, inspecting, and re-installing the pulley.
AD Requirements
This AD requires, before further flight, and thereafter at
intervals not exceeding 10 hours time-in-service (TIS), inspecting the
pulley for looseness and proper installation of the lockwire on the
pulley mount bolts.
Additionally, within 25 hours TIS, this AD requires removing the
pulley, inspecting the bolts and mounting holes with a 10X or higher
magnifying glass for damage or distortion, and re-installing the
pulley. If there is any damage or distortion, this AD requires
replacing the damaged pulley.
Differences Between This AD and the Manufacturer's Service Information
This AD requires repetitively inspecting the pulley bolts every 10
hours TIS; the ASB does not require the repetitive inspections after
re-installing the pulley.
This AD also applies to Model MBB-BK117 A-3, MBB-BK117 A-4, MBB-
BK117 B-1, and MBB-BK117 C-2 helicopters; the ASB only applies to Model
MBB-BK C-2 helicopters.
Interim Action
We consider this AD to be an interim action. The design approval
holder is currently developing a modification that will address the
unsafe condition identified in this AD. Once this modification is
developed, approved, and available, we might consider additional
rulemaking.
Costs of Compliance
We estimate that this AD will affect 75 helicopters of U.S.
Registry. We estimate that operators may incur the following costs in
order to comply with this AD. At an average labor rate of $85 per hour,
inspecting the pulley will require about .5 work-hour, for a cost per
helicopter of $43, and a total cost of $3,225 for the fleet per
inspection cycle. Inspecting and re-installing the pulley will require
about 2 work-hours, for a cost per helicopter of $170, and a total cost
of $12,750 for the fleet.
If necessary, replacing a damaged pulley would require about 2
work-hours, and required parts would cost $525, for a total cost per
helicopter of $695.
FAA's Justification and Determination of the Effective Date
Providing an opportunity for public comments prior to adopting
these AD requirements would delay implementing the safety actions
needed to correct this known unsafe condition. Therefore, we find that
the risk to the flying public justifies waiving notice and comment
prior to the adoption of this rule because the required corrective
actions must be accomplished within 25 hours TIS or 30 calendar days, a
very short time period based on the average flight hour utilization
rate of these helicopters in the air ambulance and offshore operations
industries.
Since an unsafe condition exists that requires the immediate
adoption of this AD, we determined that notice and opportunity for
public comment before issuing this AD are impracticable and that good
cause exists for making this amendment effective in less than 30 days.
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 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, 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:
[[Page 40958]]
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):
2013-12-06 Eurocopter Deutschland (Eurocopter): Amendment 39-17484;
Docket No. FAA-2013-0520; Directorate Identifier 2013-SW-027-AD.
(a) Applicability
This AD applies to Eurocopter Model MBB-BK 117 A-3, MBB-BK 117
A-4, MBB-BK 117 B-1, and MBB-BK 117 C-2 helicopters with a Metro
Aviation, Inc. (Metro) vapor-cycle air conditioning kit installed in
accordance with Supplemental Type Certificate (STC) No. SH3880SW,
certificated in any category.
(b) Unsafe Condition
This AD defines the unsafe condition as loosening of an air
conditioning drive pulley (pulley) mount bolt, which could result in
separation of the pulley from the rotor brake disc on the tail rotor
(T/R) driveshaft, damage to the T/R driveshaft, and subsequent loss
of control of the helicopter.
(c) Effective Date
This AD becomes effective July 24, 2013.
(d) Compliance
You are responsible for performing each action required by this
AD within the specified compliance time.
(e) Required Actions
(1) Before further flight, and thereafter at intervals not
exceeding 10 hours time-in-service (TIS), inspect the lockwire
securing the pulley mount bolts for proper installation and the
pulley for looseness. If the lockwire is damaged or broken, or is
not installed in a tightening direction, or if the pulley is loose,
remove and inspect the pulley as described in paragraphs (e)(2)(i)
and (e)(2)(ii) of this AD.
(2) Within 25 hours TIS:
(i) Remove the pulley from the rotor brake disc and, using a 10X
or higher power magnifying glass, inspect the bolts and mounting
holes glass for damage or distortion. If there is any damage or
distortion, replace the pulley.
(ii) Install the pulley and torque each mount bolt to 90 inch-
pounds. After torqueing, determine whether a gap exists among each
bolt head, washer, and the mating surface of the rotor brake disc.
If there is a gap, replace the pulley.
(iii) Lock wire each pulley mount bolt to its adjacent rotor
brake mounting bolt with 0.6 millimeter lockwire.
(f) Special Flight Permits
Special flight permits are prohibited.
(g) Alternative Methods of Compliance (AMOCs)
(1) The Manager, Rotorcraft Certification Office, FAA, may
approve AMOCs for this AD. Send your proposal to: Martin Crane,
Aviation Safety Engineer, Rotorcraft Certification Office,
Rotorcraft Directorate, FAA, 2601 Meacham Blvd., Fort Worth, Texas
76137; telephone (817) 222-5056; email <a href="/cdn-cgi/l/email-protection#b58298f4e3e698f4e6e298848285f5d3d4d49bd2dac3"><span class="__cf_email__" data-cfemail="093e24485f5a24485a5e24383e39496f6868276e667f">[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
(1) Metro Alert Service Bulletin No. MA145-21A-003, Revision A,
dated April 26, 2013, which is not incorporated by reference,
contains additional information about the subject of this AD. For
service information identified in this AD, contact Metro Aviation,
Inc., 1214 Hawn Ave, Shreveport, LA 71107; phone: (318) 222-5529;
Web site: <a href="http://metroproductsupport.com">metroproductsupport.com</a>. You may review a copy of the
service information at the FAA, Office of the Regional Counsel,
Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas
76137.
(2) STC No. SH3880SW, amended April 16, 2004, may be found on
the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> in Docket No. FAA-2013-
0520.
(i) Subject
Joint Aircraft Service Component (JASC) Code: 6500: Tail Rotor
Drive.
Issued in Fort Worth, Texas, on June 13, 2013.
Kim Smith,
Directorate Manager, Rotorcraft Directorate, Aircraft Certification
Service.
[FR Doc. 2013-16388 Filed 7-8-13; 8:45 am]
BILLING CODE 4910-13-P
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Retrieved: Apr 4, 2026
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