
[Federal Register Volume 77, Number 23 (Friday, February 3, 2012)]
[Proposed Rules]
[Pages 5425-5426]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-2422]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0084; Directorate Identifier 2010-SW-089-AD]
RIN 2120-AA64


Airworthiness Directives; Bell Helicopter Textron Canada Limited 
Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for the 
Bell Helicopter Textron Canada Limited (BHTC) Model 427 helicopters. 
This proposed AD is prompted by a review of the tailboom attachment 
installation, which revealed that the torque value of the bolts 
specified in the BHTC Model 427 Maintenance Manual and applied during 
manufacturing was incorrect and exceeded the torque range recommended 
for the bolts. The proposed actions are intended to prevent an over-
torque of the tailboom attachment bolt (bolt), bolt failure, loss of 
the tailboom, and subsequent loss of control of the helicopter.

DATES: We must receive comments on this proposed AD by April 3, 2012.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Docket: Go to http://www.regulations.gov. Follow the online instructions for sending your 
comments electronically.
     Fax: (202) 493-2251.
     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.
     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 http://www.regulations.gov 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 proposed AD, 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 proposed AD, contact 
Bell Helicopter Textron Canada Limited, 12,800 Rue de l'Avenir, 
Mirabel, Quebec J7J1R4, telephone (450) 437-2862 or (800) 363-8023, fax 
(450) 433-0272, or at http://www.bellcustomer.com/files/.
    You may review copies of 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: Sharon Miles, Aerospace Engineer, FAA, 
Regulations and Policy Group, 2601 Meacham Blvd., Fort Worth, Texas 
76137; telephone: (817) 222-5122; email sharon.y.miles@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

    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 might 
result from adopting the proposals in this document. The most helpful 
comments reference a specific portion of the proposal, 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 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 proposed rulemaking. Before acting on this proposal, we 
will consider all comments we receive on or before the closing date for 
comments. We will consider comments filed after the comment period has 
closed if it is possible to do so without incurring expense or delay. 
We may change this proposal in light of the comments we receive.

Discussion

    Transport Canada (TC), which is the aviation authority for Canada, 
has issued AD CF-2010-32, dated September 30, 2010 (AD CF-2010-32), to 
correct an unsafe condition for the BHTC Model 427 helicopters, serial 
numbers (S/Ns) 56001 through 56084, and S/Ns 58001 and 58002. TC 
advises that a review of the tailboom attachment installation 
determined that the torque value of the bolts specified in the BHTC 
Model 427 Maintenance Manual and applied during manufacturing exceeded 
the torque range recommended for the bolts. They state that this 
situation, if not corrected, could lead to a bolt failure, detachment 
of the tailboom, and loss of control of the helicopter.

FAA's Determination

    This helicopter model is manufactured in Canada and is type 
certificated for operation in the United States under the provisions of 
14 CFR 21.29 and the applicable bilateral agreement. Pursuant to the 
bilateral agreement, TC has kept the FAA informed of the situation 
described above. We are issuing this AD because we evaluated all 
information provided by TC and determined the unsafe condition is 
likely to exist or develop on other helicopters of these same type 
designs.

Related Service Information

    BHTC has issued Alert Service Bulletin No. 427-10-31, dated March 
1, 2010 (ASB), which specifies installing new attachment hardware with 
a reduced torque value. This ASB specifies determining the torque of 
the newly installed bolts and nuts every 1 to 5 flight hours until 
torque stabilizes at all locations, and thereafter at intervals not to 
exceed 300 flight hours. TC classified this ASB as mandatory and issued 
AD CF-2010-32 to ensure the continued airworthiness of these 
helicopters.

Proposed AD Requirements

    This proposed AD would require, within 150 hours time-in-service 
(TIS) or 90 days, whichever occurs first, the following actions:
     Remove the left upper bolt, washers, and nut. Install the 
new bolt, part number (P/N) NAS627-27; washers, P/N 140-007-29S25E6 and 
P/N NAS1149G0732P; and new nut, P/N 42FLW-720. Run the nut onto the 
threads of the mating bolt with a torque wrench and measure the 
existing tare. Any bolt and nut used must have a minimum tare of 14 
inch/lbs. Torque the nut and coat the bolt head, nut, and washers with 
appropriate corrosion preventive compound to seal the joint. Repeat 
these actions at the three remaining bolt locations.
     After installation of the new attachment hardware, at 
intervals of no less than 1 hour TIS but not exceeding 5 hours TIS, 
determine the torque of each nut until torque stabilizes at each 
attachment location. Thereafter, determine the torque of each nut at 
intervals not to exceed 300 hours TIS.
    The actions would be required to be accomplished by following 
specified

[[Page 5426]]

portions of the service bulletin described previously.

Differences Between This Proposed AD and the TC AD

    The differences between this proposed AD and the TC AD are as 
follows:
     The TC AD applies to the BHTC Model 427 helicopter, serial 
numbers 58001 and 58002; however, this proposed AD is not applicable to 
the BHTC Model 427 helicopters with these serial numbers because they 
are not eligible for an FAA Certificate of Airworthiness.

Costs of Compliance

    We estimate that this proposed AD would affect 28 helicopters of 
U.S. registry. We estimate it would take about 2.0 work-hours per 
helicopter to replace the hardware, and 1.0 work-hour per helicopter to 
determine the recurring torque value at an average labor rate of $85 
per work hour. Required parts would cost about $488 per helicopter. 
Based on these figures, we estimate for the first year the total cost 
per helicopter to be $913, and the total cost impact on U.S. operators 
to be $25,564. This estimated total cost assumes attachment hardware 
will be replaced on all affected helicopters, the torque will be 
considered stabilized after one torquing, and the recurring 300 hour 
TIS torque determination will be accomplished twice a year.

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 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, I certify this proposed 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);
    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 proposed 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.

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

    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 adding the following new 
Airworthiness Directive (AD):

Bell Helicopter Textron Canada Limited (BHTC): Docket No. FAA-2012-
0084; Directorate Identifier 2010-SW-089-AD.

    (a) Applicability. This AD applies to model 427 helicopters, 
serial numbers 56001 through 56084, certificated in any category.
    (b) Unsafe Condition. This AD defines the unsafe condition as an 
over torque of the tailboom attachment bolt (bolt). This condition 
could result in bolt failure, loss of the tailboom, and subsequent 
loss of control of the helicopter.
    (c) 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.
    (d) Required Actions.
    (1) Within 150 hours time-in-service (TIS) or 90 days, whichever 
occurs first, replace the tailboom attachment hardware (attachment 
hardware) as follows:
    (i) Remove the left upper bolt, washers, and nut.
    (ii) Install a new bolt, part number (P/N) NAS627-27; washer, P/
N 140-007-29S25E6; washer(s), P/N NAS1149G0732P; and new nut, P/N 
42FLW-720 in accordance with paragraphs 5.a) through 5.d) of the 
Accomplishment Instructions in BHTC Alert Service Bulletin No. 427-
10-31, dated March 1, 2010 (ASB).
    (iii) Run the nut onto the threads of the mating bolt with a 
torque wrench and measure the existing tare torque. Any bolt and nut 
used must have a minimum tare torque value of 14 inch/lbs.
    (iv) Torque the nut in accordance with paragraphs 5.f) and 5.g) 
of the ASB.
    (v) Coat the bolt head, nut, and washers with appropriate 
corrosion preventive compound to seal the joint.
    (vi) At each remaining attachment location, remove the bolt, 
washers, and nut, and install the attachment hardware in accordance 
with paragraphs (d)(1)(ii) through (d)(1)(v) of this AD.
    (2) After installation of the new attachment hardware, at 
intervals of not less than 1 hour TIS but not exceeding 5 hours TIS, 
determine the torque of each nut until the torque stabilizes at each 
attachment location. Thereafter, at intervals not to exceed 300 
hours TIS, determine the torque of each nut. When determining the 
torque, it is acceptable to use the minimum tare torque of 14 inch/
lbs (1.58 Nm) added to the minimum torque range of 550-560 inch/lbs 
(62.1 to 63.3 Nm). If you remove corrosion preventative compound 
during the torquing, recoat the bolt head, nut, and washers with 
appropriate corrosion preventive compound to seal the joint.
    (e) Alternative Methods of Compliance (AMOC).
    (1) The Manager, Safety Management Group, FAA, may approve AMOCs 
for this AD. Send your proposal to: Sharon Miles, 2601 Meacham 
Blvd., Fort Worth, Texas 76137; telephone: (817) 222-5122; fax: 
(817) 222-5961, email sharon.y.miles@faa.gov.
    (2) For operations conducted under a Part 119 operating 
certificate or under 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.
    (f) Additional Information. The subject of this AD is addressed 
in Transport Canada AD CF-2010-32, dated September 30, 2010.
    (g) Subject. Joint Aircraft Service Component (JASC) Code: 5302: 
Rotorcraft Tailboom.


    Issued in Fort Worth, Texas, on January 23, 2012.
Kim Smith,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2012-2422 Filed 2-2-12; 8:45 am]
BILLING CODE 4910-13-P


