AD 2012-18-09
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| 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 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 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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