AD 2003-04-12
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bell Helicopter Textron Canada Limited | 427 | Airworthiness Directives; Bell Helicopter Textron Canada Limited Model 427 Helicopters |
Unsafe Condition
Main rotor blades contacting the top of the fin, causing an upper tuning weight to become loose, which could lead to a main rotor blade striking an auxiliary fin, loss of a tuning weight, impact with a tail or main rotor blade, and subsequent loss of control of the helicopter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Modify the auxiliary fin assemblies and revise the Limitations section of the Rotorcraft Flight Manual (RFM) to reduce the never-exceed speed (Vne) for a tail rotor pedal stop failure.
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
Bell Helicopter Textron Canada Limited Model 427 helicopters.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
This amendment adopts a new airworthiness directive (AD) for the specified Bell Helicopter Textron Canada (Bell) model helicopters that requires modifying the auxiliary fin assemblies and revising the Limitations section of the Rotorcraft Flight Manual (RFM) to reduce the never-exceed speed (Vne) for a tail rotor pedal stop failure. This amendment is prompted by several incidents of main rotor blades contacting the top of the fin that have resulted in an upper tuning weight (weight) becoming loose. The actions specified by this AD are intended to prevent a main rotor blade from striking an auxiliary fin, loss of a tuning weight, impact with a tail or main rotor blade, and subsequent loss of control of the helicopter.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 68, Number 40 (Friday, February 28, 2003)]
[Rules and Regulations]
[Pages 9523-9525]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 03-4477]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2001-SW-43-AD; Amendment 39-13061; AD 2003-04-12]
RIN 2120-AA64
Airworthiness Directives; Bell Helicopter Textron Canada Limited
Model 427 Helicopters
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment adopts a new airworthiness directive (AD) for
the specified Bell Helicopter Textron Canada (Bell) model helicopters
that requires modifying the auxiliary fin assemblies and revising the
Limitations section of the Rotorcraft Flight Manual (RFM) to reduce the
never-exceed speed (Vne) for a tail rotor pedal stop failure. This
amendment is prompted by several incidents of main rotor blades
contacting the top of the fin that have resulted in an upper tuning
weight (weight) becoming loose. The actions specified by this AD are
intended to prevent a main rotor blade from striking an auxiliary fin,
loss of a tuning weight, impact with a tail or main rotor blade, and
subsequent loss of control of the helicopter.
DATES: Effective April 4, 2003.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of April 4, 2003.
ADDRESSES: The service information referenced in this AD may be
obtained from Bell Helicopter Textron Canada, 12,800 Rue de l'Avenir,
Mirabel, Quebec J7J1R4, telephone (450) 437-2862 or (800) 363-8023, fax
(450) 433-0272. This information may be examined at the FAA, Office of
the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663,
Fort Worth, Texas; or at the Office of the Federal Register, 800 North
Capitol Street, NW., suite 700, Washington, DC.
FOR FURTHER INFORMATION CONTACT: Sharon Miles, Aviation Safety
Engineer, FAA, Rotorcraft Directorate, Regulations Group, Fort Worth,
Texas 76193-0111, telephone (817) 222-5122, fax (817) 222-5961.
SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal
Aviation Regulations (14 CFR part 39) to add an AD for Bell Model 427
helicopters was published in the
[[Page 9524]]
Federal Register on November 28, 2001 (66 FR 59377). That NPRM would
have required modifying the fins, part number (P/N) 427-035-836-101 and
427-035-836-102, to relocate the weights, P/N 407-023-003-145. That
proposal recognized that relocating the tuning weights was an interim
action and anticipated that contact between the main rotor blades and
the top portion of the fins would be addressed in a separate AD.
However, prior to publishing the final rule based on that NPRM, the
manufacturer published service information about reducing the height of
the fins. Further, Transport Canada issued a revised AD requiring the
height reduction in Canada. Hence, reducing the height of the fins made
the relocation of the tuning weights unnecessary, therefore a
supplemental proposal was published in the Federal Register on October
18, 2002 (67 FR 64326). That action proposed to require modifying the
auxiliary fin assemblies to reduce the height and revising the
Limitations section of the RFM to reduce the Vne for a tail rotor pedal
stop failure from 80 knots indicated airspeed (KIAS) to 60 KIAS.
Transport Canada, the airworthiness authority for Canada, notified
the FAA that an unsafe condition may exist on Bell Model 427
helicopters. Transport Canada advises of several ground incidents of
main rotor blades contacting the top portion of a fin. Such incidents
occurred on helicopters with an internal gross weight capability of
6,350 lbs. and the larger auxiliary fin assemblies.
Bell has issued Alert Service Bulletin 427-01-7, dated November 16,
2001 (ASB), which specifies reducing the height of the auxiliary fin
assembly, part number (P/N) 427-035-836-101, -102, -105, and -106
within 300 hours time-in-service (TIS). Transport Canada classified
this ASB as mandatory and issued AD No. CF-2001-05R1, dated February
13, 2002, to ensure the continued airworthiness of these helicopters in
Canada.
Interested persons have been afforded an opportunity to participate
in the making of this amendment. No comments were received on the
proposal or the FAA's determination of the cost to the public. The FAA
has determined that air safety and the public interest require the
adoption of the rule as proposed with the exception of minor non-
substantive changes and updating the Rotorcraft Flight Manual from
Revision 3 to Revision 5, which is referenced in Note 2 of the AD.
The FAA estimates that 30 helicopters of U.S. registry will be
affected by this AD, that it will take approximately 12 work hours per
helicopter to accomplish the actions, and that the average labor rate
is $60 per work hour. Required parts will cost approximately $1,685 per
helicopter. Based on these figures, the total cost impact of the AD on
U.S. operators is estimated to be $72,150 to perform the modifications
and revisions for the entire fleet.
The regulations adopted herein 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. Therefore, it
is determined that this final rule does not have federalism
implications under Executive Order 13132.
For the reasons discussed above, I certify that this action (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); 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. A final evaluation has been prepared for this action
and it is contained in the Rules Docket. A copy of it may be obtained
from the Rules Docket at the location provided under the caption
ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
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
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. Section 39.13 is amended by adding a new airworthiness directive
to read as follows:
2003-04-12 Bell Helicopter Textron Canada: Amendment 39-13061.
Docket No. 2001-SW-43-AD.
Applicability: Model 427 helicopters, serial numbers 56001
through 56030 with auxiliary fin assemblies, part numbers 427-035-
836-101, -102, -105, or -106, installed, certificated in any
category.
Note 1: This AD applies to each helicopter identified in the
preceding applicability provision, regardless of whether it has been
otherwise modified, altered, or repaired in the area subject to the
requirements of this AD. For helicopters that have been modified,
altered, or repaired so that the performance of the requirements of
this AD is affected, the owner/operator must request approval for an
alternative method of compliance in accordance with paragraph (c) of
this AD. The request should include an assessment of the effect of
the modification, alteration, or repair on the unsafe condition
addressed by this AD; and if the unsafe condition has not been
eliminated, the request should include specific proposed actions to
address it.
Compliance: Required as indicated, unless accomplished
previously.
To prevent a main rotor blade from striking an auxiliary fin,
loss of an upper tuning weight, impact with a tail or main rotor
blade, and subsequent loss of control of the helicopter:
(a) Within 60 days, modify auxiliary fin assemblies, part
numbers (P/N) 427-035-836-101, -102, -105, or -106, in accordance
with the Accomplishment Instructions in Bell Helicopter Textron
Alert Service Bulletin No. 427-01-07, dated November 16, 2001.
(b) After accomplishing paragraph (a) of this AD, reduce the
never-exceed speed (Vne) limitation for a pedal stop failure from 80
knots indicated airspeed (KIAS) to 60 KIAS.
Note 2: Bell Helicopter Textron Rotorcraft Flight Manual BHT-
427-FM-2, Revision 5, dated April 23, 2002, incorporates the reduced
airspeed limitation for a pedal stop failure.
(c) An alternative method of compliance or adjustment of the
compliance time that provides an acceptable level of safety may be
used if approved by the Manager, Regulations Group, Rotorcraft
Directorate, FAA. Operators shall submit their requests through an
FAA Principal Maintenance Inspector, who may concur or comment and
then send it to the Manager, Regulations Group.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Regulations Group.
(d) Special flight permits may be issued in accordance with
sections 21.197 and 21.199 of the Federal Aviation Regulations (14
CFR 21.197 and 21.199) to operate the helicopter to a location where
the requirements of this AD can be accomplished.
(e) The modification shall be done in accordance with the
Accomplishment Instructions in Bell Helicopter Textron Alert Service
Bulletin No. 427-01-07, dated November 16, 2001. This incorporation
by reference was approved by the Director of the Federal Register in
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be
obtained from Bell Helicopter Textron Canada, 12,800 Rue de
l'Avenir, Mirabel, Quebec J7J1R4, telephone (450) 437-2862 or (800)
363-8023, fax (450) 433-0272. 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 Office of the Federal
Register,
[[Page 9525]]
800 North Capitol Street, NW., suite 700, Washington, DC.
(f) This amendment becomes effective on April 4, 2003.
Note 4: The subject of this AD is addressed in Transport Canada
(Canada) AD No. CF-2001-05R1, dated February 13, 2002.
Issued in Fort Worth, Texas, on February 14, 2003.
David A. Downey,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 03-4477 Filed 2-27-03; 8:45 am]
BILLING CODE 4910-13-P
Source: Official FAA Source ↗
Retrieved: Apr 6, 2026
Rights: U.S. Government Public Domain
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