AD 2012-18-09

Recurring final rule

Airworthiness Directives; Bell Helicopter Textron Canada Helicopters

AD Number
2012-18-09
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2012-0337
FR Citation
77 FR 57005

Applicability

TypeManufacturerModelDetails
aircraft Bell Helicopter Textron Canada Limited 407 Airworthiness Directives; Bell Helicopter Textron Canada Helicopters

Unsafe Condition

An incorrect torque value of the tailboom attachment bolt specified in the BHTC Model 407 Maintenance Manual and applied during manufacturing, which exceeds the torque range recommended for the bolts.

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

Required Actions

Replace the tailboom-attachment hardware, including bolts, washers, and nuts, as specified in the BHTC Alert Service Bulletin No. 407-10-93, Revision A. Perform initial and recurring determinations of the torque on the nuts of the tailboom-attachment bolts at all four attachment locations.

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

Compliance Time

Within 90 days or at the next scheduled 600-hour inspection, whichever comes first, for helicopters with 7000 hours or less time-in-service (TIS). For helicopters with more than 7000 hours TIS, within 150 hours TIS or 90 days, whichever comes first.

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

Affected Aircraft

Bell Helicopter Textron Canada Limited (BHTC) Model 407 helicopters, serial numbers 53000 through 53990, certificated in any category.

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 the Bell Helicopter Textron Canada Limited (BHTC) Model 407 helicopters. This AD requires you to replace tailboom-attachment hardware (attachment hardware), and perform initial and recurring determinations of the torque on the nuts of the tailboom-attachment bolts (bolts) at all four attachment locations. This AD was prompted by a review of the tailboom-attachment installation, which revealed that the torque value of the bolts specified in the BHTC Model 407 Maintenance Manual and applied during manufacturing was incorrect and exceeded the torque range recommended for the bolts. The actions required by this AD are intended to prevent an over-torque of a bolt, bolt failure, loss of the tailboom, and subsequent loss of control of the helicopter.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 77, Number 180 (Monday, September 17, 2012)]
[Rules and Regulations]
[Pages 57005-57007]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2012-22038]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0337; Directorate Identifier 2010-SW-090-AD; 
Amendment 39-17185; AD 2012-18-09]
RIN 2120-AA64


Airworthiness Directives; Bell Helicopter Textron Canada 
Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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

SUMMARY: We are adopting a new airworthiness directive (AD) for the 
Bell Helicopter Textron Canada Limited (BHTC) Model 407 helicopters. 
This AD requires you to replace tailboom-attachment hardware 
(attachment hardware), and perform initial and recurring determinations 
of the torque on the nuts of the tailboom-attachment bolts (bolts) at 
all four attachment locations. This AD was prompted by a review of the 
tailboom-attachment installation, which revealed that the torque value 
of the bolts specified in the BHTC Model 407 Maintenance Manual and 
applied during manufacturing was incorrect and exceeded the torque 
range recommended for the bolts. The actions required by this AD are 
intended to prevent an over-torque of a bolt, bolt failure, loss of the 
tailboom, and subsequent loss of control of the helicopter.

DATES: This AD is effective October 22, 2012.
    The Director of the Federal Register approved the incorporation by 
reference of a certain document listed in this AD as of October 22, 
2012.

ADDRESSES: For service information identified in this 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 <a href="http://www.bellcustomer.com/files/">http://www.bellcustomer.com/files/</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.
    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, any 
incorporated-by-reference service information, the economic evaluation, 
any comments received, and other

[[Page 57006]]

information. The street address for the Docket Operations Office 
(phone: 800-647-5527) is U.S. Department of Transportation, Docket 
Operations Office, M-30, West Building Ground Floor, Room W12-140, 1200 
New Jersey Avenue SE., Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Sharon Miles, Aerospace Engineer, FAA, 
Regulations and Policy Group, 2601 Meacham Blvd., Fort Worth, Texas 
76137; telephone: (817) 222-5122; fax: (817) 222-5961; email: 
<a href="/cdn-cgi/l/email-protection#e4978c85968b8aca9dca898d888197a4828585ca838b92"><span class="__cf_email__" data-cfemail="addec5ccdfc2c383d483c0c4c1c8deedcbcccc83cac2db">[email&#160;protected]</span></a>.

SUPPLEMENTARY INFORMATION: 

Discussion

    On March 29, 2012, at 77 FR 18970, the Federal Register published 
our notice of proposed rulemaking (NPRM), which proposed to amend 14 
CFR part 39 to include an AD that would apply to BHTC Model 407 
helicopters. That NPRM proposed to require replacing attachment 
hardware and performing initial and recurring determinations of the 
torque on the nuts of the tailboom-attachment bolts at all four 
attachment locations. The proposed requirements were intended to 
prevent an over-torque of a bolt, bolt failure, loss of the tailboom, 
and subsequent loss of control of the helicopter.
    Transport Canada, which is the aviation authority for Canada, has 
issued Canadian AD No. CF-2010-33, dated September 30, 2010, to correct 
an unsafe condition for the BHTC Model 407 helicopters, serial numbers 
(S/N) 53000 through 53990. Transport Canada advises that a review of 
the tailboom-attachment installation determined that the torque value 
of the bolts specified in the BHTC Model 407 Maintenance Manual and 
applied during manufacturing, exceeded the torque range recommended for 
the bolts. Transport Canada states that this situation, if not 
corrected, could lead to a bolt failure, detachment of the tailboom, 
and subsequent loss of control of the helicopter.

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 
Canada and are approved for operation in the United States. Pursuant to 
our bilateral agreement with Canada, Transport Canada, its technical 
representative, has notified us of the unsafe condition described in 
the Transport Canada AD. We are issuing this AD because we evaluated 
all information provided by Transport Canada and determined the unsafe 
condition exists and is likely to exist or develop on other helicopters 
of the same type designs and that air safety and the public interest 
require adopting the AD requirements as proposed.

Differences Between This AD and the Transport Canada AD

    The differences between this AD and the Transport Canada AD are as 
follows:
    <bullet> This AD uses the term ``hours time-in-service'' to 
describe compliance times, and Transport Canada AD uses the term ``air 
time'';
    <bullet> For helicopters with 7000 hours or less TIS, the Transport 
Canada AD requires accomplishing the actions in the AD at the next 
scheduled 600-hour inspection or by December 31, 2010, whichever occurs 
first. This AD requires accomplishing the actions at the next scheduled 
600-hour inspection or 90 days, whichever occurs first.
    <bullet> This AD uses the term ``determine the torque'' when 
referring to the torque on a nut, and the Transport Canada AD uses the 
term ``perform a torque check.''

Related Service Information

    BHTC has issued Alert Service Bulletin No. 407-10-93, Revision A, 
dated August 30, 2010 (ASB), which specifies installing new attachment 
hardware with a reduced torque value. This ASB specifies performing a 
torque check of the newly installed bolts and nuts every one to five 
flight hours until the torque stabilizes at all locations, and 
thereafter at intervals not to exceed 300 flight hours. Transport 
Canada classified this ASB as mandatory and issued AD CF-2010-33 to 
ensure the continued airworthiness of these helicopters.

Costs of Compliance

    We estimate that this AD will affect 552 helicopters of U.S. 
registry. We estimate it will take about two work-hours per helicopter 
to replace the hardware and one work-hour per helicopter to determine 
the recurring torque value at an average labor rate of $85 per work 
hour. Required parts will cost about $498 per helicopter. Based on 
these figures, we estimate for the first year the total cost per 
helicopter to be $923, and the total cost impact on U.S. operators to 
be $509,496. This estimated total cost assumes attachment hardware will 
be replaced on all affected helicopters, the torque will be considered 
stabilized after determining the torque value once, and the 300-hour 
TIS recurring 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 helicopters identified in this 
rulemaking action.

Regulatory Findings

    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 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:


[[Page 57007]]


    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):

2012-18-09 Bell Helicopter Textron Canada (BHTC): Amendment 39-
17185; Docket No. FAA-2012-0337; Directorate Identifier 2010-SW-090-
AD.

(a) Applicability

    This AD applies to BHTC Model 407 helicopters, serial numbers 
53000 through 53990, certificated in any category.

(b) Unsafe Condition

    This AD defines the unsafe condition as an incorrect torque 
value of the tailboom attachment bolt (bolt) specified in the BHTC 
Model 407 Maintenance Manual and applied during manufacturing, which 
exceeds the torque range recommended for the bolts. This condition 
could result in an over-torque of the bolt, bolt failure, loss of 
the tailboom, and subsequent loss of control of the helicopter.

(c) Effective Date

    This AD becomes effective October 22, 2012.

(d) Compliance

    You are responsible for performing each action required by this 
AD within the specified compliance time unless accomplished 
previously.

(e) Required Actions

    (1) For helicopters with 7000 hours or less time-in-service 
(TIS), at the next 600 hours scheduled inspection, or 90 days, 
whichever comes first; and for helicopters with more than 7000 hours 
TIS, within 150 hours TIS or 90 days, whichever comes 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) NAS627-30; washer, P/
N 140-007-29S25E6; washer(s), P/N NAS1149G0732P; and new nut, P/N 
42FLW-720 in accordance with paragraphs 2.a) through paragraph 3.e) 
of the ``Accomplishment Instructions: Replacement of tailboom 
attachment bolts and nuts'' section and Figure 2 in the BHTC Alert 
Service Bulletin No. 407-10-93, Revision A, dated August 30, 2010 
(ASB).
    (iii) Remove the opposite right upper bolt, washers, and nut, 
and accomplish the requirements in paragraph (e)(1)(ii) of this AD.
    (iv) Remove the left lower bolt, washers, and nut.
    (v) Install a new bolt, (P/N) NAS626-26; washer, P/N 140-007-
25S22E6; washer(s), P/N NAS1149G0663P; and new nut, P/N 42FLW-624 in 
accordance with paragraphs 6.a) through 7.e) of the ``Accomplishment 
Instructions: Replacement of tailboom attachment bolts and nuts'' 
section and Figure 2 in the ASB.
    (vi) Remove the right lower bolt, washers, and nut, and 
accomplish the requirements in paragraph (e)(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, referring to Figure 2 of the ASB. Apply the 
minimum specified torque of the range, plus the minimum acceptable 
tare torque of 14 inch/lbs (1.58 Nm) for the upper nuts, and 9.5 
inch/lbs (1.07 Nm) for the lower nuts.
    (3) At intervals not to exceed 300 hours TIS, determine the 
torque of each of the four attachment nuts, referring to Figure 2 of 
the ASB. Apply the minimum specified torque of the range plus the 
minimum acceptable tare torque of 14 inch/lbs (1.58 Nm) for the 
upper nuts, and 9.5 inch/lbs (1.07 Nm) for the lower nuts. If the 
proper torque has not been retained since the last torque 
determination, remove and inspect the tailboom assembly for damage, 
corrosion, improper assembly, and condition. If the tailboom 
assembly is airworthy, replace the attachment hardware in accordance 
with the requirements in paragraphs (e)(1)(i) through (e)(1)(vi) and 
determine that the torque has stabilized in accordance with 
paragraph (e)(2) of this AD. Replace any unairworthy tailboom 
assembly with an airworthy tailboom assembly.

(f) Alternative Methods of Compliance (AMOCs)

    (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: <a href="/cdn-cgi/l/email-protection#21524940534e4f0f580f4c484d4452614740400f464e57"><span class="__cf_email__" data-cfemail="384b50594a57561641165551545d4b785e5959165f574e">[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.

(g) Additional Information

    The subject of this AD is addressed in the Transport Canada 
Civil Aviation (TCCA) AD CF-2010-33, dated September 30, 2010.

(h) Subject

    Joint Aircraft Service Component (JASC) Code: Rotorcraft 
tailboom.

(i) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) 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) Bell Helicopter Textron Canada Limited Alert Service 
Bulletin No. 407-10-93, Revision A, dated August 30, 2010.
    (ii) Reserved.
    (3) For service information identified in this 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 <a href="http://www.bellcustomer.com/files/">http://www.bellcustomer.com/files/</a>.
    (4) You may review a copy of this service information at the 
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 August 30, 2012.
Kim Smith,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2012-22038 Filed 9-14-12; 8:45 am]
BILLING CODE 4910-13-P

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