[Federal Register Volume 63, Number 56 (Tuesday, March 24, 1998)]
[Rules and Regulations]
[Pages 14026-14028]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-7414]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-SW-58-AD; Amendment 39-10421; AD 98-07-03]
RIN 2120-AA64
Airworthiness Directives; Bell Helicopter Textron, Inc. Model 412
Helicopters and Agusta S.p.A. Model AB412 Helicopters
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This amendment adopts a new airworthiness directive (AD) that
is applicable to Bell Helicopter Textron, Inc. (Bell) Model 412
helicopters and Agusta S.p.A. (Agusta) Model AB412 helicopters. This
action requires a temporary reduction of the never-exceed velocity
(Vne) limitation until an inspection of the tail rotor yoke (yoke)
assembly for fatigue damage and installation of a redesigned yoke
flapping stop are accomplished. Recurring periodic and special
inspections to detect occurrences of yoke overload are also required.
This amendment is prompted by laboratory tests and engineering analyses
that indicated that the yoke assembly is susceptible to fatigue damage
due to unforeseen static and dynamic loading of the tail rotor against
the original flapping stop. The actions specified in this AD are
intended to prevent fatigue failure of the yoke that could result in
loss of control of the tail rotor and subsequent loss of control of the
helicopter.
DATES: Effective April 8, 1998.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of April 8, 1998.
Comments for inclusion in the Rules Docket must be received on or
before May 26, 1998.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Office of the Regional Counsel, Southwest Region,
Attention: Rules Docket No. 97-SW-58-AD, 2601 Meacham Blvd., Room 663,
Fort Worth, Texas 76137.
The service information referenced in this AD may be obtained from
Bell Helicopter Textron, Inc., P.O. Box 482, Fort Worth, Texas 76101,
telephone (817) 280-3391, fax (817) 280-6466 for the Bell Model 412
helicopters; and
[[Page 14027]]
Agusta S.p.A., 21017 Cascina Costa di Samarate (VA), Via Giovanni
Agusta 520, telephone (0331) 229111, fax (0331) 229605-222595 for the
Agusta Model AB412 helicopters. 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. Shep Blackman, Aerospace Engineer,
FAA, Rotorcraft Directorate, Rotorcraft Standards Staff, 2601 Meacham
Blvd., Fort Worth, Texas 76137, telephone (817) 222-5296, fax (817)
222-5961.
SUPPLEMENTARY INFORMATION: The Registro Aeronautico Italiano (RAI),
which is the airworthiness authority for Italy, recently notified the
FAA that an unsafe condition may exist on Agusta Model AB412
helicopters, and since the Bell Model 412 helicopters are of similar
type design, a similar unsafe condition could exist on those models.
The RAI advises installing a temporary airspeed placard, inspecting the
yoke assembly, and installing a redesigned tail rotor flapping stop.
Bell has issued Bell Helicopter Textron Alert Service Bulletin
(ASB) 412-96-89, Revision A, dated October 17, 1997 and Bell Helicopter
Textron ASB 412CF-96-01, dated September 3, 1996, for the Bell Model
412 helicopters; and Agusta has issued Agusta Bolletino Tecnico
(Technical Bulletin) No. 412-65, dated December 2, 1996 for the Agusta
Model AB412 helicopters. Both service bulletins and the technical
bulletin specify an immediate temporary reduction in the maximum
airspeed, installing a cockpit placard for this limitation, and
incorporating a temporary flight manual supplement until the yoke
historical records are researched for previous damage history; until an
x-ray diffraction inspection is performed on the yoke to detect fatigue
damage; and until a frangible tail rotor flapping stop/yield indicator,
P/N 212-011-713-103, is installed. A repetitive 25-hours time-in-
service inspection to detect damaging tail rotor flapping stop contact
due to a hard landing, sudden stoppage, or miscellaneous power on/off
incidents has been added. The RAI classified the Agusta technical
bulletin as mandatory and issued AD 97-223 in order to assure the
continued airworthiness of these helicopters in Italy.
The Bell Model 412 helicopters are manufactured in the U.S. and are
type certificated for operation in the United States under the
provisions of Sec. 21.21 of the Federal Aviation Regulations (14 CFR
21.21). The Agusta Model AB412 helicopters are manufactured in Italy
and are type certificated for operation in the United States under the
provisions of Sec. 21.29 of the Federal Aviation Regulations (14 CFR
21.29) and the applicable bilateral airworthiness agreement. Pursuant
to this bilateral airworthiness agreement, the RAI has kept the FAA
informed of the situation described above. The FAA has examined the
findings of the RAI, reviewed all available information, and determined
that AD action is necessary for products of these type designs that are
certificated for operation in the United States.
Since an unsafe condition has been identified that is likely to
exist or develop on other Bell Model 412 and Agusta Model AB412
helicopters of the same type designs registered or eligible for
registration in the United States, this AD is being issued to prevent
fatigue failure of the yoke that could result in loss of control of the
helicopter. This AD requires a temporary reduction of the Vne
limitation until an inspection of the yoke assembly for fatigue damage
and installation of a redesigned yoke flapping stop is accomplished,
and includes additional periodic and special inspections to detect
occurrences of yoke overload.
The short compliance time involved is required because the
previously described critical unsafe condition can adversely affect the
controllability of the helicopter. Therefore, a temporary reduction in
Vne is required prior to further flight, and this AD must be issued
immediately.
Since a situation exists that requires the immediate adoption of
this regulation, it is found that notice and opportunity for prior
public comment hereon are impracticable, and that good cause exists for
making this amendment effective in less than 30 days.
The FAA estimates that 124 helicopters of U.S. registry will be
affected by this AD, that it will take approximately 6.5 hours per
helicopter to accomplish the installation of a placard, the inspection,
and the installation of the yoke. Required parts will cost
approximately $511 per helicopter. Based on these figures, the total
cost impact of this AD on U.S. operators is estimated to be $111,724.
Comments Invited
Although this action is in the form of a final rule that involves
requirements affecting flight safety and, thus, was not preceded by
notice and an opportunity for public comment, comments are invited on
this rule. Interested persons are invited to comment on this rule by
submitting such written data, views, or arguments as they may desire.
Communications should identify the Rules Docket number and be submitted
in triplicate to the address specified under the caption ADDRESSES. All
communications received on or before the closing date for comments will
be considered, and this rule may be amended in light of the comments
received. Factual information that supports the commenter's ideas and
suggestions is extremely helpful in evaluating the effectiveness of the
AD action and determining whether additional rulemaking action would be
needed.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the rule that might
suggest a need to modify the rule. All comments submitted will be
available, both before and after the closing date for comments, in the
Rules Docket for examination by interested persons. A report that
summarizes each FAA-public contact concerned with the substance of this
AD will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this rule must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket No. 97-SW-58-AD.'' The postcard will be date stamped and
returned to the commenter.
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.
The FAA has determined that this regulation is an emergency
regulation that must be issued immediately to correct an unsafe
condition in aircraft, and that it is not a ``significant regulatory
action'' under Executive Order 12866. It has been determined further
that this action involves an emergency regulation under DOT Regulatory
Policies and Procedures (44 FR 11034, February 26, 1979). If it is
determined that this emergency regulation otherwise would be
significant under DOT Regulatory Policies and Procedures, a final
regulatory evaluation will be prepared and placed in the Rules Docket.
A copy of it, if filed, may be obtained from the
[[Page 14028]]
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 98-07-03 Bell Helicopter Textron, Inc. and Agusta S.p.A.:
Amendment 39-10421. Docket No. 97-SW-58-AD.
Applicability: Bell Helicopter Textron, Inc. Model 412
helicopters, serial numbers (S/N) 33001 through 33213, 34001 through
34024, 36001 through 36121, 46400 through 46434, 46437, and Agusta
S.p.A. Model AB412 helicopters, S/N prior to and including S/N
25806, and S/N 25901; 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 (e) 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 as indicated, unless accomplished
previously.
To prevent fatigue failure of the tail rotor yoke (yoke), that
could result in loss of control of the helicopter, accomplish the
following:
(a) Before further flight, review the historical records of the
yoke assembly, part number (P/N) 212-011-702-all dash numbers, for
any static or dynamic incident history, other than normal usage,
that could have imposed a bending load on the yoke, but did not
require yoke assembly replacement; for example, an incident in which
a damaged tail rotor blade was replaced due to a blade strike. If
such a history exists, replace the yoke with an airworthy yoke.
(b) Before further flight, unless paragraph (c) of this AD has
been accomplished previously:
(1) Install a Never Exceed Velocity (Vne) red line at 120 knots
indicated airspeed (KIAS) on the pilot and copilot airspeed
indicators using red tape or paint, and a slippage indicator on the
instrument case and glass.
(2) Install a placard made of material that is not easily
erased, disfigured, or obscured on the instrument panel in clear
view of the pilot and copilot: ``Observe temporary Maximum Never
Exceed (Vne) airspeed red line (marked at 120 knots indicated
airspeed (KIAS)). Vne is 20 KIAS less than the value presented on
the airspeed limitation placard for each ambient condition.''
(3) Insert the applicable Bell Helicopter Textron 412 Temporary
Revision, dated August 16, 1996, into the Model 412 Rotorcraft
Flight Manual (RFM), or Agusta AB412EP Temporary Revision No. 2 into
the Model AB412 RFM.
(c) Within 180 calendar days:
(1) Remove yoke assembly, P/N 212-011-702-all dash numbers, and
replace it with an airworthy yoke assembly, P/N 212-011-702-all dash
numbers, with zero hours time-in-service (TIS), or an airworthy yoke
(regardless of TIS) that has passed a one-time x-ray diffraction
inspection in accordance with Bell Helicopter Textron ASB 412-96-89,
Revision A, dated October 17, 1997; Bell Helicopter Textron ASB
412CF-96-01, dated September 3, 1996; or, Agusta Bolletino Tecnico
(Technical Bulletin) No. 412-65, dated December 2, 1996, whichever
is applicable.
(2) Install an airworthy tail rotor flapping stop, P/N 212-011-
713-103.
(3) If requirements are accomplished in accordance with paragraphs
(c)(1) and (c)(2) of this AD, remove the 120 KIAS redline from the
pilot and copilot airspeed indicators; remove the Vne airspeed
restriction placard; and remove the Bell Helicopter Textron 412
Temporary Revision, dated August 16, 1996, or Agusta AB Temporary
Revision No. 2, as applicable, from the RFM.
(d) After accomplishing paragraph (c) of this AD, thereafter
inspect the yoke assembly and tail rotor flapping stop at intervals
not to exceed 25 hours TIS in accordance with Part III, Recurring
25-Hour Special Inspection and Conditional Inspection Requirement,
of Bell Helicopter Textron ASB 412-96-89, Revision A, dated October
17, 1996; Bell Helicopter Textron ASB 412CF-96-01, dated September
3, 1996; or Agusta Bolletino Tecnico (Technical Bulletin) No. 412-
65, dated December 2, 1996, as applicable.
(e) 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 Standards Staff,
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 Standards Staff.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Rotorcraft Standards Staff.
(f) 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 at airspeeds not to
exceed 120 KIAS to a location where the requirements of this AD can
be accomplished.
(g) The inspections and installations shall be done in
accordance with Bell ASB 412-96-89, Revision A, dated October 17,
1997; Bell Helicopter Textron ASB 412CF-96-01, dated September 3,
1996; or Agusta Technical Bulletin No. 412-65, dated December 2,
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, telephone (817) 280-3391, fax
(817) 280-6466; or Agusta, 21017 Cascina Costa di Samarate (VA), Via
Giovanni Agusta 520, telephone (0331) 229111, fax (0331) 229605-
222595. 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.
(h) This amendment becomes effective on April 8, 1998.
Note 3: The subject of this AD is addressed in Registro
Aeronautico Italiano (Italy) AD 97-223, dated January 8, 1997.
Issued in Fort Worth, Texas, on March 16, 1998.
Eric Bries,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 98-7414 Filed 3-23-98; 8:45 am]
BILLING CODE 4910-13-U
