[Federal Register Volume 63, Number 62 (Wednesday, April 1, 1998)]
[Rules and Regulations]
[Pages 15754-15756]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-8466]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 96-SW-28-AD; Amendment 39-10429; AD 98-07-09]
RIN 2120-AA64
Airworthiness Directives; Bell Helicopter Textron, Inc. Model
47B, 47B-3, 47D, 47D-1, 47G, 47G-2, 47G-2A, 47G-2A-1, 47G-3, 47G-3B,
47G-3B-1, 47G-3B-2, 47G-3B-2A, 47G-4, 47G-4A, 47G-5, 47G-5A, 47H-1,
47J, 47J-2, 47J-2A, and 47K Helicopters
AGENCY: Federal Aviation Administration, DOT.
[[Page 15755]]
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: This amendment adopts a new airworthiness directive (AD),
applicable to Bell Helicopter Textron, Inc. (BHTI) Model 47B, 47B-3,
47D, 47D-1, 47G, 47G-2, 47G-2A, 47G-2A-1, 47G-3, 47G-3B, 47G-3B-1, 47G-
3B-2, 47G-3B-2A, 47G-4, 47G-4A, 47G-5, 47G-5A, 47H-1, 47J, 47J-2, 47J-
2A, and 47K helicopters, that requires installing a safety washer kit
designed to preclude separation of the stabilizer bar damper link
(damper link) if the damper link rod end bushing (bushing) loosens and
exits the damper link rod end. This amendment is prompted by two
reported incidents in which the bushings loosened and exited the damper
link rod ends, allowing the damper link to slide over the retention
bolt and separate from the stabilizer bar (in the first incident), and
from the hydraulic damper (in the second incident). The actions
specified by this AD are intended to prevent failure of the damper link
assembly, which can result in degraded control response and subsequent
loss of control of the helicopter.
DATES: Effective May 6, 1998.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the federal Register as
of May 6, 1998.
ADDRESSES: The service information referenced in this AD may be
obtained from Bell Helicopter Textron, Inc., P.O. Box 482, Fort Worth,
Texas 76101. 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: Mr. Jurgen E. Priester, Aerospace
Engineer, Rotorcraft Certification Office, Rotorcraft Directorate, FAA,
2601 Meacham Blvd., Fort Worth, Texas 76137; telephone (817) 222-5159,
fax (817) 222-5783.
SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal
Aviation Regulations (14 CFR part 39) to include an airworthiness
directive (AD) that is applicable to BHTI Model 47B, 47B-3, 47D, 47D-1,
47G, 47G-2, 47G-2A, 47G-2A-1, 47G-3, 47G-3B, 47G-3B-1, 47G-3B-2, 47G-
3B-2A, 47G-4, 47G-4A, 47G-5, 47G-5A, 47H-1, 47J, 47J-2, 47J-2A, and 47K
helicopters was published in the Federal Register on May 20, 1997 (62
FR 27554). That action proposed to require installing a safety washer
kit designed to preclude separation of the damper link if the bushing
loosens and exits the damper link rod end.
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the one comment received.
The commenter states that the helicopters are controllable with one
damper link disconnected. The commenter also states that a standard
AN970-3 safety washer drilled out to 0.250-inch and coned should be
allowed to be used as an alternate part to the BHTI safety washer kit.
The commenter states that the modified AN970-3 safety washer is the
same configuration as the BHTI safety washers used on the lateral
cyclic torque tube and only costs pennies.
The FAA does not concur with the comment. The commenter did not
provide any support for his statement that the helicopters are
controllable with one damper link disconnected. The commenter indicates
that he has been installing a modified safety washer on BHTI Model 47
series helicopters for decades. Although the commenter may believe that
his modified safety washer is as airworthy as BHTI's safety washer, he
has provided no engineering design data that support his assertion or
show that his modified safety washer is of the same configuration or of
the same material quality as BHTI's safety washer. Without such
supporting data, the FAA cannot approve the use of the commenter's
modified safety washer.
After careful review of the available data, including the comments
noted above, the FAA has determined that air safety and the public
interest require the adoption of the rule as proposed.
The FAA estimates that 1,868 helicopters of U.S. registry will be
affected by this AD, that it will take approximately 1 work hour per
helicopter to accomplish the required actions, and that the average
labor rate is $60 per work hour. Required parts will cost approximately
$188 per helicopter. Based on these figures, the total cost impact of
the AD on U.S. operators is estimated to be $463,264.
The regulations adopted herein will not have substantial direct
effects 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, in
accordance with Executive Order 12612, it is determined that this final
rule does not have sufficient federalism implications to warrant the
preparation of a Federalism Assessment.
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:
AD 98-07-09 Bell Helicopter Textron, Inc.: Amendment 39-10429.
Docket No. 96-SW-28-AD.
Applicability: Model 47B, 47B-3, 47D, 47D-1, 47G, 47G-2, 47G-2A,
47G-2A-1, 47G-3, 47G-3B, 47G-3B-1, 47G-3B-2, 47G-3B-2A, 47G-4, 47G-
4A, 47G-5, 47G-5A, 47H-1, 47J, 47J-2, 47J-2A, and 47K helicopters,
certificated in any category.
Note 1: This AD applies to each helicopter identified in the
preceding applicability provision, regardless of whether it has been
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 use the authority
provided in paragraph (b) to request approval from the FAA. This
approval may address either no action, if the current configuration
eliminates the unsafe condition, or different actions necessary to
address the unsafe condition described in this AD. Such a request
should include an assessment of the effect of the changed
configuration on the unsafe condition addressed by this AD. In no
case does the presence of any modification, alteration, or repair
remove any helicopter from the applicability of this AD.
Compliance: Required within the next 100 hours time-in-service
or within the next 120
[[Page 15756]]
calendar days, whichever occurs first, unless accomplished
previously.
To prevent failure of the stabilizer bar damper link assembly,
which can result in degraded control response and subsequent loss of
control of the helicopter, accomplish the following:
(a) Remove the stabilizer bar damper link assemblies from the
helicopter, install a safety washer kit, part number (P/N) CA-047-
96-022-1, and reinstall the stabilizer bar damper link assemblies
onto the helicopter in accordance with the Accomplishment
Instructions contained in Bell Helicopter Textron, Inc. Alert
Service Bulletin No. 47-96-22, dated August 16, 1996.
(b) 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, Rotorcraft Certification Office,
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, Rotorcraft Certification
Office.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Rotorcraft Certification Office.
(c) Special flight permits may be issued in accordance with
Secs. 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.
(d) The installation shall be done in accordance with Bell
Helicopter Textron, Inc. Alert Service Bulletin No. 47-96-22, dated
August 16, 1996. 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, Inc., P.O. Box 482, Fort Worth, Texas 76101. 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, 800 North Capitol Street, NW., suite
700, Washington, DC.
(e) This amendment becomes effective on May 6, 1998.
Issued in Fort Worth, Texas, on March 24, 1998.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 98-8466 Filed 3-31-98; 8:45 am]
BILLING CODE 4910-13-U
