AD 2006-26-51

final rule

Airworthiness Directives; Eurocopter Deutschland GmbH Model MBB-BK 117 C-2 Helicopters

AD Number
2006-26-51
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2006-26721
FR Citation
72 FR 13679
Technical illustration of a helicopter rotor hub assembly
Problem area Rotor system

Applicability

TypeManufacturerModelDetails
aircraft Eurocopter 117 C-2 Airworthiness Directives; Eurocopter Deutschland GmbH Model MBB-BK 117 C-2 Helicopters

Unsafe Condition

The threaded portion of the tail rotor control lever containing a dynamic weight broke off during flight, leading to severe vibrations and potential loss of control.

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

Required Actions

Mark the position of the tail rotor control lever dynamic weights, remove the split pins and weights, and visually inspect the tail rotor control lever. Replace the tail rotor control lever if necessary. Repeat the visual inspection within 10 hours time-in-service (TIS) and every 25 hours TIS thereafter. Reassemble the tail rotor control lever following the appropriate maintenance instruction.

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

Compliance Time

Before further flight

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

Affected Aircraft

Eurocopter Deutschland GmbH Model MBB-BK 117 C-2 helicopters

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

Federal Register Abstract

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2006-26-51, which was sent previously to all known U.S. owners and operators of Eurocopter Deutschland GmbH (ECD) Model MBB-BK 117 C-2 helicopters by individual letters. This AD requires, before further flight, marking the position of the tail rotor control lever dynamic weights (weights), removing the split pins and the weights, and visually inspecting and replacing, if necessary, the tail rotor control lever before further flight. This AD also requires, within 10 hours time-in-service (TIS), and thereafter at intervals not to exceed 25 hours TIS, repeating the visual inspection of the tail rotor control lever and replacing any unairworthy tail rotor control lever with an airworthy tail rotor control lever before further flight. Also required is reassembling the tail rotor control lever by following the appropriate maintenance instruction. This amendment is prompted by an in-flight incident in which the threaded portion of the tail rotor control lever containing a dynamic weight broke off leading to severe vibrations. The actions specified by this AD are intended to prevent separation of the weights in flight, severe vibration, and subsequent loss of control of the helicopter.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 72, Number 56 (Friday, March 23, 2007)]
[Rules and Regulations]
[Pages 13679-13681]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: E7-5139]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-26721; Directorate Identifier 2006-SW-28-AD; 
Amendment 39-14961; AD 2006-26-51]
RIN 2120-AA64


Airworthiness Directives; Eurocopter Deutschland GmbH Model MBB-
BK 117 C-2 Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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

SUMMARY: This document publishes in the Federal Register an amendment 
adopting Airworthiness Directive (AD) 2006-26-51, which was sent 
previously to all known U.S. owners and operators of Eurocopter 
Deutschland GmbH (ECD) Model MBB-BK 117 C-2 helicopters by individual 
letters. This AD requires, before further flight, marking the position 
of the tail rotor control lever dynamic weights (weights), removing the 
split pins and the weights, and visually inspecting and replacing, if 
necessary, the tail rotor control lever before further flight. This AD 
also requires, within 10 hours time-in-service (TIS), and thereafter at 
intervals not to exceed 25 hours TIS, repeating the visual inspection 
of the tail rotor control lever and replacing any unairworthy tail 
rotor control lever with an airworthy tail rotor control lever before 
further flight. Also required is reassembling the tail rotor control 
lever by following the appropriate maintenance instruction. This 
amendment is prompted by an in-flight incident in which the threaded 
portion of the tail rotor control lever containing a dynamic weight 
broke off leading to severe vibrations. The actions specified by this 
AD are intended to prevent separation of the weights in flight, severe 
vibration, and subsequent loss of control of the helicopter.

DATES: Effective April 9, 2007, to all persons except those persons to 
whom it was made immediately effective by Emergency AD 2006-26-51, 
issued on December 22, 2006, which contained the requirements of this 
amendment.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of April 9, 2007.
    Comments for inclusion in the Rules Docket must be received on or 
before May 22, 2007.

ADDRESSES: Use one of the following addresses to submit comments on 
this AD:
    <bullet> DOT Docket Web site: Go to <a href="http://dms.dot.gov">http://dms.dot.gov</a> and follow 
the instructions for sending your comments electronically;
    <bullet> Government-wide rulemaking Web site: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a> and follow the instructions for sending your 
comments electronically;
    <bullet> Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590;
    <bullet> Fax: (202) 493-2251; or
    <bullet> Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    You may get the service information identified in this AD from 
American Eurocopter Corporation, 2701 Forum Drive, Grand Prairie, Texas 
75053-4005, telephone (972) 641-3460, fax (972) 641-3527.

Examining the Docket

    You may examine the docket that contains the AD, any comments, and 
other information on the Internet at <a href="http://dms.dot.gov">http://dms.dot.gov</a>, or in person 
at the Docket Management System (DMS) Docket Offices between 9 a.m. and 
5 p.m., Monday through Friday, except Federal holidays. The Docket 
Office (telephone (800) 647-5227) is located on the plaza level of the 
Department of Transportation Nassif Building at the street address 
stated in the ADDRESSES section. Comments will be available in the AD 
docket shortly after the DMS receives them.

FOR FURTHER INFORMATION CONTACT: Charles Harrison, Aviation Safety 
Engineer, FAA, Rotorcraft Directorate, Safety Management Group, Fort 
Worth, Texas 76193-0110, telephone (817) 222-5128, fax (817) 222-5961.

SUPPLEMENTARY INFORMATION: On December 22, 2006, the FAA issued 
Emergency AD 2006-26-51 for the specified model helicopters, which 
requires, before further flight, marking the position of the tail rotor 
control lever dynamic weights (weights), removing the split pins and 
the weights, and by referring to Figure 1 of the manufacturer's service 
bulletin, visually inspecting the area around the split pin bore for 
score marks, notches, scratches, or other damage that exceeds the 
maintenance manual limitations or a crack and replacing any unairworthy 
tail rotor control lever before further flight. The AD also requires, 
within 10 hours TIS, and thereafter at intervals not to exceed 25 hours 
TIS, repeating the visual inspection of the tail rotor control lever 
and replacing any unairworthy tail rotor control lever with an 
airworthy tail rotor control lever before further flight. Also required 
is reassembling the tail rotor control lever by following the 
appropriate maintenance instruction. That action was prompted by an in-
flight incident in which a dynamic weight broke off the tail rotor 
control lever subsequently leading to considerable vibrations. A visual 
inspection revealed that the threaded portion of the control lever 
containing the dynamic weight had broken off. This condition, if not 
corrected, could result in separation of the weights in flight, severe 
vibration, and subsequent loss of control of the helicopter.

[[Page 13680]]

    The Luftfahrt-Bundesamt (LBA) has issued an Emergency AD in 
accordance with Article 10.1 of European Union Regulation 1592/2002. 
The LBA, the airworthiness authority for the Federal Republic of 
Germany, notified the FAA that an unsafe condition may exist on these 
helicopter models. The LBA advises of an in-flight incident in which a 
dynamic weight broke off the tail rotor control lever resulting in 
considerable vibrations. The LBA advises that this can lead to reduced 
controllability of the helicopter.
    The FAA has reviewed Eurocopter Alert Service Bulletin No. MBB BK 
117 C-2-64A-002, dated December 21, 2006 (ASB), which describes 
procedures for initial and recurrent visual inspections of the tail 
rotor control lever. The ASB specifies inspecting the area around the 
split pin bore for damage, and if score marks, notching, scratching, a 
crack, or something similar are detected to contact ECD customer 
support. In addition, the manufacturer states in that ASB that it is 
effective for Model MBB BK117 C-2 helicopters, Serial Number (S/N) 9075 
and higher, and those helicopters from S/N 9004 up to and including S/N 
9074 on which Alert Service Bulletin MBB BK 117 C-2-67-006, dated July 
25, 2006, (SB MBB BK 117-C-2-67-006) has been accomplished. The 
referenced SB MBB BK 117-C-2-67-006, states that it offers improvements 
with regard to a reduction of the operational pedal control forces. 
These improvements involved two modifications (1) Installing modified 
pedal control levers, and (2) installing an optimized tail rotor 
control lever assembly ``consisting of modified weights and modified 
control lever pre-assys.'' Installing the optimized tail rotor control 
lever assembly involved replacing the 2 control levers, Part Number (P/
N) B642M1009102, with 2 control levers, P/N B642M1009103, and replacing 
the 4 weights, P/N B642M1011201 with 4 weights, P/N B642M1011202. The 
LBA classified this ASB as mandatory and issued LBA AD D-2006-428, 
effective December 22, 2006, to ensure the continued airworthiness of 
these helicopters in Germany.
    This helicopter model is manufactured in the Federal Republic of 
Germany and is type certificated for operation in the United States 
under the provisions of 14 CFR 21.29 and the applicable bilateral 
agreement. The FAA has examined the findings of the LBA, reviewed all 
available information, and determined that AD action is necessary for 
products of this type design that are certificated for operation in the 
United States.
    Since the unsafe condition described is likely to exist or develop 
on other ECD Model MBB-BK 117 C-2 helicopters of the same type design, 
the FAA issued Emergency AD 2006-26-51 to prevent separation of the 
weights in flight, severe vibration, and subsequent loss of control of 
the helicopter. The AD requires the following:
    <bullet> Before further flight, marking the position of the 
weights, removing the split pins, removing the weights, and visually 
inspecting the tail rotor control lever in the area around the split 
pin bore for score marks, notching, scratching, or a crack.
    <bullet> If you find score marks, notching, or scratches, that 
exceed the maintenance manual limits, or find a crack, replacing the 
tail rotor control lever with an airworthy tail rotor control lever 
before further flight.
    <bullet> If you do not find score marks, notching, scratches, or a 
crack, within 10 hours TIS, and thereafter at intervals not to exceed 
25 hours TIS, repeating the visual inspection of the tail rotor control 
lever.
    <bullet> After any repetitive inspection, if you find score marks, 
notching, or scratches, that exceed the maintenance manual limits or 
find a crack, replacing the tail rotor control lever with an airworthy 
tail rotor control lever before further flight.
    <bullet> Reassembling the tail rotor control lever by following the 
appropriate maintenance instruction.
    The actions must be accomplished in accordance with the specified 
portions of the ASB described previously. The short compliance time 
involved is required because the previously described critical unsafe 
condition can adversely affect the structural integrity and 
controllability of the helicopter. Therefore, the actions previously 
described are required at the specified short time intervals, and this 
AD must be issued immediately.
    Since it was found that immediate corrective action was required, 
notice and opportunity for prior public comment thereon were 
impracticable and contrary to the public interest, and good cause 
existed to make the AD effective immediately by individual letters 
issued on December 22, 2006 to all known U.S. owners and operators of 
ECD Model MBB-BK 117 C-2 helicopters. These conditions still exist, and 
the AD is hereby published in the Federal Register as an amendment to 
14 CFR 39.13 to make it effective to all persons.
    The FAA estimates that this AD will affect 26 helicopters on the 
U.S. registry. The before-flight inspection, the 10-hour TIS 
inspection, and each of the repetitive 25-hour TIS inspections 
(assuming 24 repetitive inspections per year per helicopter) including 
marking the position of the weights, removing the split pins, removing 
the weights, and visually inspecting the tail rotor control lever and 
reassemblying an airworthy tail rotor control lever will take about 1 
work hour per inspection per helicopter. Replacing 1 tail rotor control 
lever and 1 weight will take about 3 work hours. The average labor rate 
is $80 per work hour. Required parts, if necessary, will cost about 
$4,166 for each tail rotor control lever (2 per helicopter); $496 for 
each weight (4 per helicopter); and $.21 for each cotter pin (4 per 
helicopter). Based on these figures, we estimate the total cost impact 
of the AD on U.S. operators for the first year will be $181,532 ($6,982 
per helicopter, assuming 1 tail rotor control lever and 1 weight are 
replaced on each helicopter in the fleet during the first year).

Comments Invited

    This AD is a final rule that involves requirements that affect 
flight safety and was not preceded by notice and an opportunity for 
public comment; however, we invite you to submit any written data, 
views, or arguments regarding this AD. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2006-26721; 
Directorate Identifier 2006-SW-28-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the AD. We will consider 
all comments received by the closing date and may amend the AD in light 
of those comments.
    We will post all comments we receive, without change, to <a href="http://dms.dot.gov">http://dms.dot.gov</a>, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this AD. Using the search function of our docket 
Web site, you can find and read the comments to any of our dockets, 
including the name of the individual who sent the comment. You may 
review the DOT's complete Privacy Act Statement in the Federal Register 
published on April 11, 2000 (65 FR 19477-78), or you may visit <a href="http://dms.dot.gov">http://dms.dot.gov</a>.

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,

[[Page 13681]]

or on the distribution of power and responsibilities among the various 
levels of government.
    For the reasons discussed above, I certify that the regulation:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866;
    2. Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979); 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.
    We prepared an economic evaluation of the estimated costs to comply 
with this AD. See the DMS to examine the economic evaluation.

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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (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. Section 39.13 is amended by adding a new airworthiness directive to 
read as follows:

2006-26-51 Eurocopter Deutschland GmbH: Amendment 39-14961. Docket 
No. FAA-2006-26721; Directorate Identifier 2006-SW-28-AD.

Applicability

    Model MBB-BK 117 C-2 helicopters, serial number (S/N) 9075 and 
higher, and those helicopters from S/N 9004 up to and including 
9074, on which Service Bulletin MBB BK117 C-2-67-006 has been 
accomplished, with a tail rotor control lever B642M1009103, 
installed, certificated in any category.

    Note 1: The referenced Eurocopter Alert Service bulletin MBB BK 
117 C-2-67-006, dated July 25, 2006, pertains to the subject of this 
AD. That ASB states that it offers improvements with regard to a 
reduction of the operational pedal control forces and involves two 
modifications. One of the modifications involves installing an 
optimized tail rotor control lever assembly ``consisting of modified 
weights and modified control lever pre-assys.'' Installing the 
optimized tail rotor control lever assembly, in part, involved 
replacing the 2 control levers, part number (P/N) B642M1009102, with 
2 control levers, P/N B642M1009103, and replacing the 4 weights, P/N 
B642M1011201, with 4 weights, P/N B642M1011202.

Compliance

    Required as indicated, unless accomplished previously.
    To prevent separation of the tail rotor control lever dynamic 
weights (weights) in flight, severe vibration, and subsequent loss 
of control of the helicopter, accomplish the following:
    (a) Before further flight, mark the position of the weights, 
remove the split pins, remove the weights, and visually inspect the 
tail rotor control lever in the area around the split pin bore for 
score marks, notching, scratching, or a crack. Conduct the 
inspection by following the Accomplishment Instructions, paragraph 
3A(1) and Figure 1 of Eurocopter Alert Service Bulletin No. MBB 
BK117 C-2-64A-002, dated December 21, 2006 (ASB).
    (1) If you find score marks, notching, or scratches, that exceed 
the maintenance manual limits, or find a crack, replace the tail 
rotor control lever with an airworthy tail rotor control lever 
before further flight.
    (2) If you do not find score marks, notching, scratches, or a 
crack, within 10 hours time-in-service (TIS), and thereafter at 
intervals not to exceed 25 hours TIS, repeat the visual inspection 
of the tail rotor control lever as described in paragraph (a) of 
this AD.
    (3) After any repetitive inspection, if you find score marks, 
notching, or scratches, that exceed the maintenance manual limits or 
find a crack, replace the tail rotor control lever with an airworthy 
tail rotor control lever before further flight.
    (4) Reassemble the tail rotor control lever by following the 
appropriate maintenance instructions and the Accomplishment 
Instructions, paragraph 3A(4) and Figure 1 of the ASB.
    (b) To request an alternative method of compliance or a 
different compliance time for this AD, follow the procedures in 14 
CFR 39.19. Contact the Manager, Safety Management Group, FAA, ATTN: 
Charles Harrison, Aviation Safety Engineer, FAA, Rotorcraft 
Directorate, Fort Worth, Texas 76193-0110, telephone (817) 222-5128, 
fax (817) 222-5961, for information about previously approved 
alternative methods of compliance.
    (c) Special flight permits will not be issued.
    (d) The inspections and reassembly shall be done in accordance 
with the specified portions of Eurocopter Alert Service Bulletin No. 
MBB BK117 C-2-64A-002, dated December 21, 2006. The Director of the 
Federal Register approved this incorporation by reference in 
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be 
obtained from American Eurocopter Corporation, 2701 Forum Drive, 
Grand Prairie, Texas 75053-4005, telephone (972) 641-3460, fax (972) 
641-3527. Copies may be inspected at the FAA, Office of the Regional 
Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, 
Texas or 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/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
    (e) This amendment becomes effective on April 9, 2007, to all 
persons except those persons to whom it was made immediately 
effective by Emergency AD 2006-26-51, issued December 22, 2006, 
which contained the requirements of this amendment.

    Note 2: The subject of this AD is addressed in Luftfahrt-
Bundesamt (Federal Republic of Germany) AD D-2006-428, dated 
December 22, 2006.


    Issued in Fort Worth, Texas, on March 14, 2007.
David A. Downey,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. E7-5139 Filed 3-22-07; 8:45 am]
BILLING CODE 4910-13-P

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