AD 2014-06-51

final rule

Airworthiness Directives; Airbus Helicopters Deutschland GmbH (Airbus Helicopters) (Type Certificate Previously Held by Eurocopter Deutschland GmbH) Helicopters

AD Number
2014-06-51
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2014-0395
FR Citation
79 FR 41117
Supersedes
2013-12-06

Applicability

TypeManufacturerModelDetails
aircraft Airbus Helicopters Deutschland GmbH MBB-BK 117 A-3 Airworthiness Directives; Airbus Helicopters Deutschland GmbH (Airbus Helicopters) (Type Certificate Previously Held by Eurocopter Deutschland GmbH) Helicopters
aircraft Airbus Helicopters Deutschland GmbH MBB-BK 117 A-4 Airworthiness Directives; Airbus Helicopters Deutschland GmbH (Airbus Helicopters) (Type Certificate Previously Held by Eurocopter Deutschland GmbH) Helicopters
aircraft Airbus Helicopters Deutschland GmbH MBB-BK 117 B-1 Airworthiness Directives; Airbus Helicopters Deutschland GmbH (Airbus Helicopters) (Type Certificate Previously Held by Eurocopter Deutschland GmbH) Helicopters
aircraft Airbus Helicopters Deutschland GmbH MBB-BK 117 C-2 Airworthiness Directives; Airbus Helicopters Deutschland GmbH (Airbus Helicopters) (Type Certificate Previously Held by Eurocopter Deutschland GmbH) Helicopters

Unsafe Condition

Pulleys with insufficient thread depth may allow attaching bolts to come loose, resulting in the pulley detaching from the rotor brake disc, subsequent damage to the tail rotor (T/R) driveshaft, and loss of control of the helicopter.

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

Required Actions

Inspect each pulley attaching bolt hole to determine if there is sufficient depth of the threads. If the depth is less than 0.61 inch, remove the pulley. If the depth is sufficient, install dual locking tabs under each pulley attaching bolt. Submit a report of the inspection findings to the FAA.

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

Compliance Time

Within 5 hours time-in-service

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

Affected Aircraft

Airbus Helicopters 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. vapor-cycle air conditioning kit pulley (P/N 30001) installed.

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

Federal Register Abstract

We are publishing a new airworthiness directive (AD) for Airbus Helicopters 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 certain Metro Aviation, Inc. (Metro), vapor-cycle air conditioning kit pulley (pulley) installed, which was sent previously to all known U.S. owners and operators of these helicopters. This AD supersedes AD 2013-12-06, which required inspecting the pulley for looseness and properly installed lockwire and re-installing the pulley. Since we issued AD 2013-12-06, we received a report of a possible design and manufacturing deficiency in some pulleys wherein they did not have sufficient thread depth, allowing the pulley to detach from the rotor brake disc. This AD requires inspecting each pulley attaching bolt hole to determine if there is sufficient depth of the threads and either removing the pulley if the depth is insufficient or installing dual locking tabs under each pulley attaching bolt if the depth is sufficient. These actions are intended to prevent the pulley from detaching, resulting in damage to the tail rotor (T/R) driveshaft, and subsequent loss of control of the helicopter.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 79, Number 135 (Tuesday, July 15, 2014)]
[Rules and Regulations]
[Pages 41117-41120]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2014-16387]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2014-0395; Directorate Identifier 2014-SW-016-AD; 
Amendment 39-17876; AD 2014-06-51]
RIN 2120-AA64


Airworthiness Directives; Airbus Helicopters Deutschland GmbH 
(Airbus Helicopters) (Type Certificate Previously Held by Eurocopter 
Deutschland GmbH) Helicopters

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule; request for comments.

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

SUMMARY: We are publishing a new airworthiness directive (AD) for 
Airbus Helicopters 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 certain Metro Aviation, Inc. 
(Metro), vapor-cycle air conditioning kit pulley (pulley) installed, 
which was sent previously to all known U.S. owners and operators of 
these helicopters. This AD supersedes AD 2013-12-06, which required 
inspecting the pulley for looseness and properly installed lockwire and 
re-installing the pulley. Since we issued AD 2013-12-06, we received a 
report of a possible design and manufacturing deficiency in some 
pulleys wherein they did not have sufficient thread depth, allowing the 
pulley to detach from the rotor brake disc. This AD requires inspecting 
each pulley attaching bolt hole to determine if there is sufficient 
depth of the threads and either removing the pulley if the depth is 
insufficient or installing dual locking tabs under each pulley 
attaching bolt if the depth is sufficient. These actions are intended 
to prevent the pulley from detaching, resulting in damage to the tail 
rotor (T/R) driveshaft, and subsequent loss of control of the 
helicopter.

DATES: This AD becomes effective July 30, 2014 to all persons except 
those persons to whom it was made immediately effective by Emergency AD 
(EAD) 2014-06-51, issued on March 24, 2014, which contains the 
requirements of this AD.
    The Director of the Federal Register approved the incorporation by 
reference of a certain document listed in this AD as of July 30, 2014.
    We must receive comments on this AD by September 15, 2014.

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 economic evaluation, any 
incorporated by reference service information, 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.,

[[Page 41118]]

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) 222-5170; 
email <a href="/cdn-cgi/l/email-protection#3e09137f686d137f6d69130f090e7e585f5f10595148"><span class="__cf_email__" data-cfemail="4473690512176905171369757374042225256a232b32">[email&#160;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, 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

    On June 13, 2013, we issued AD 2013-12-06, Amendment 39-17484 (78 
FR 40956, July 9, 2013) (AD 2013-12-06), for Eurocopter Deutschland 
GmbH (now Airbus Helicopters) 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 vapor-cycle 
air conditioning kit installed in accordance with Supplemental Type 
Certificate No. SH3880SW. AD 2013-12-06 required repetitively 
inspecting the air conditioning drive pulley for looseness and properly 
installed lockwire, and also required reinstalling the pulley. AD 2013-
12-06 resulted from two reports of the pulley detaching from the rotor 
brake disk on the T/R driveshaft. We issued AD 2013-12-06 to prevent 
separation of the pulley, damage to the T/R driveshaft, and subsequent 
loss of control of the helicopter.

Actions Since AD 2013-12-06 Was Issued

    After we issued AD 2013-12-06, Metro developed a procedure to 
install a tabbed washer underneath the bolt heads securing the pulley 
to the rotor disc. This procedure was intended to provide a secondary 
locking feature to the bolts, and to relieve the requirement for 
repetitive inspections of the safety wire which secures the bolts. On 
December 20, 2013, Metro requested and we approved this procedure as a 
global Alternative Method of Compliance (AMOC) for AD 2013-12-06 in 
lieu of performing the repetitive inspections required by paragraph (e) 
of that AD.
    On March 10, 2014, we received a report that an attaching bolt 
would not seat on the mating surface of the pulley. Compliance with the 
AMOC revealed a possible design deficiency and a manufacturing defect 
in some pulleys. Metro has determined that the pulley, along with two 
additional pulleys from other helicopters, did not have sufficient 
thread depth. This condition may allow the attaching bolts to come 
loose, resulting in the pulley detaching from the rotor brake disc, 
subsequent damage to the T/R driveshaft, and loss of control of the 
helicopter.
    On March 24, 2014, we issued EAD 2014-06-51, which superseded AD 
2013-12-06, for those to whom it was made immediately effective. EAD 
2014-06-51 requires inspecting the pulley to determine if there is 
sufficient depth of the threads and removing the pulley if there is not 
sufficient depth. EAD 2014-06-51 also requires installing a dual 
locking tab on each pulley attaching bolt and reporting the inspection 
findings to the FAA. Finally, EAD 2014-06-51 revises the applicability 
to helicopters with a pulley, P/N 30001, installed rather than with the 
air conditioning kit installed because this pulley has been determined 
to be the unsafe condition. EAD 2014-06-51 was sent previously to all 
known U.S. owners and operators of these helicopters. The actions in 
EAD 2014-06-51 are intended to prevent the pulley detaching from the 
rotor brake disc, subsequent damage to the T/R driveshaft, and loss of 
control of the helicopter.

FAA's Determination

    We are issuing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of these same type 
designs.

Related Service Information

    We reviewed Metro Alert Service Bulletin (ASB) No. MA145-21B-003, 
Revision B, dated December 20, 2013 (ASB MA145-21B-003), which 
describes procedures for installing a dual-locking tab on the air 
conditioning drive pulley attachment bolts.
    Since we issued EAD 2014-06-51, Metro released ASB No. MA145-21-
004, Revision IR, dated March 24, 2014, which describes procedures for 
inspecting the air conditioning drive pulley thread depth. This AD 
continues to reference ASB MA145-21B-003.

AD Requirements

    This AD requires, within 5 hours time-in-service, inspecting each 
pulley attaching bolt hole to determine if there is sufficient depth of 
the threads. If the depth is less than 0.61 inch, this AD requires 
removing the pulley. This AD also requires installing dual locking tabs 
under each pulley attaching bolt by following the Accomplishment 
Instructions, paragraphs 3.E. through 3.G., of ASB MA145-21B-003. This 
AD also requires submitting a report of the inspection findings to the 
FAA.

Differences Between This AD and the Service Information

    This AD requires determining the depth of the threaded portion of 
the pulley attaching bolt holes; the service information does not.

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 work-
hour, inspecting the pulley bolt holes, and installing the tabbed 
washers will require 6 work hours, and required parts will cost $100, 
for a cost per helicopter of $610 and a total cost of $45,750 for the 
fleet.
    Reviewing instructions, collecting and reviewing information, and 
submitting a report to the FAA will require 0.5 work-hour, for a cost 
per helicopter of $43 and a cost of $3,225 for the fleet.
    If necessary, replacing a pulley will require about 2 work-hours, 
and required parts would cost $800, for a total cost per helicopter of 
$970.

Paperwork Reduction Act

    A federal agency may not conduct or sponsor, and a person is not 
required to respond to, nor shall a person be subject to penalty for 
failure to comply with a collection of information subject to the

[[Page 41119]]

requirements of the Paperwork Reduction Act unless that collection of 
information displays a current valid OMB control number. The control 
number for the collection of information required by this AD is 2120-
0056. The paperwork cost associated with this AD has been detailed in 
the Costs of Compliance section of this document and includes time for 
reviewing instructions, as well as completing and reviewing the 
collection of information. Therefore, all reporting required by this AD 
is mandatory. Comments concerning the accuracy of this burden and 
suggestions for reducing the burden should be directed to the FAA at 
800 Independence Ave. SW., Washington, DC 20591. ATTN: Information 
Collection Clearance Officer, AES-200.

FAA's Justification and Determination of the Effective Date

    Providing an opportunity for public comments before adopting these 
AD requirements would delay implementing the safety actions needed to 
correct this known unsafe condition. Therefore, we found and continue 
to find that the risk to the flying public justifies waiving notice and 
comment prior to adopting this rule because the required corrective 
actions must be done within 5 hours time-in-service, a very short time 
period based on the average flight-hour utilization rate of these 
helicopters.
    Since it was found that immediate corrective action was required, 
notice and opportunity for prior public comment before issuing this AD 
were impracticable and contrary to the public interest and that good 
cause existed to make the AD effective immediately by EAD 2014-06-51, 
issued on March 24, 2014, to all known U.S. owners and operators of 
these helicopters. These conditions still exist and the AD is hereby 
published in the Federal Register as an amendment to section 39.13 of 
the Federal Aviation Regulations (14 CFR 39.13) to make it effective to 
all persons.

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:

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 removing Airworthiness Directive (AD) 
2013-12-06, Amendment 39-17484 (78 FR 40956, July 9, 2013), and adding 
the following new AD:

2014-06-51 Airbus Helicopters Deutschland GmbH (Airbus Helicopters) 
(Type Certificate Previously Held By Eurocopter Deutschland GmbH) 
Helicopters: Amendment 39-17876; Docket No. FAA-2014-0395; 
Directorate Identifier 2014-SW-016-AD.

(a) Applicability

    This AD applies to Airbus Helicopters 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., vapor-cycle air conditioning kit pulley 
(pulley) part number (P/N) 30001 installed in accordance with 
Supplemental Type Certificate (STC) No. SH3880SW.

(b) Unsafe Condition

    This AD defines the unsafe condition as insufficient thread 
depth which could allow the attaching bolts to come loose, resulting 
in the pulley detaching from the rotor brake disc, subsequent damage 
to the tail rotor (T/R) driveshaft, and loss of control of the 
helicopter.

(c) Effective Date

    This AD becomes effective July 30, 2014 to all persons except 
those persons to whom it was made immediately effective by Emergency 
AD 2014-06-51, issued on March 24, 2014, which contains the 
requirements of this AD.

(d) Affected ADs

    This AD supersedes AD 2013-12-06, Amendment 39-17484 (78 FR 
40956, July 9, 2013).

(e) 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.

(f) Required Actions

    Within 5 hours time-in-service, inspect each pulley attaching 
bolt hole to determine the depth:
    (1) Relieve tension from the compressor drive belt and remove 
each bolt that attaches the pulley to the rotor brake disc. Do not 
remove all three bolts at the same time.
    (2) Remove AN960-416 washer or MAI-145-DUAL LOCK TAB washer.
    (3) Using a bolt or screw with \1/4\-28 threads with 0.5 inch of 
threads and a minimum of 0.8 inch grip length, coat the shank with 
blue dye or permanent marker and thread into hole until threads have 
lightly bottomed (finger tight). Scribe the shank flush with the 
face of the rotor brake disk. Measure distance from end to scribe 
mark (length protruding into assembly). This dimension represents 
total depth of threads and stack-up of the brake disk.
    (4) If the depth measures less than 0.61 inch, remove the 
pulley.
    (5) If the depth measures 0.61 inch or more, install dual 
locking tabs as described in the Accomplishment Instructions, 
paragraphs 3.E. through 3.G., of Metro Aviation, Inc., Alert Service 
Bulletin No. MA145-21B-003, Revision B, dated December 20, 2013.

(g) Reporting Requirement

    Within 10 days after inspecting the pulley as required by 
paragraph (f)(3) of this AD, submit a report with the helicopter 
model, helicopter serial number, hole number 1 thread depth, hole 
number 2 thread depth (if measured), and hole number 3 thread depth

[[Page 41120]]

(if measured) to the person identified in paragraph (h)(1) of this 
AD.

(h) 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) 222-5170; email <a href="/cdn-cgi/l/email-protection#46716b0710156b0715116b7771760620272768212930"><span class="__cf_email__" data-cfemail="b2859ff3e4e19ff3e1e59f838582f2d4d3d39cd5ddc4">[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, 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.

(i) Additional Information

    (1) Metro Aviation, Inc., Alert Service Bulletin No. MA145-21-
004, Revision IR, dated March 24, 2014, 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. SH3380SW, 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-2014-
0395.

(j) Subject

    Joint Aircraft Service Component (JASC) Code: 6500: Tail Rotor 
Drive.

(k) 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) Metro Aviation, Inc., Alert Service Bulletin No. MA145-21B-
003, Revision B, dated December 20, 2013.
    (ii) Reserved.
    (3) For Metro Aviation, Inc., 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>.
    (4) You may view this service information at FAA, Office of the 
Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, 
Fort Worth, Texas 76137. 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, call (202) 741-6030, or go to: <a href="http://www.archives.gov/federal-register/cfr/ibr-locations.html">http://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.

    Issued in Fort Worth, Texas, on June 16, 2014.
Lance T. Gant,
Acting Directorate Manager, Rotorcraft Directorate, Aircraft 
Certification Service.
[FR Doc. 2014-16387 Filed 7-14-14; 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.