[Federal Register: February 19, 2003 (Volume 68, Number 33)]
[Rules and Regulations]
[Page 7910-7911]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr19fe03-7]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2001-SW-45-AD; Amendment 39-13053; AD 2003-04-05]
RIN 2120-AA64
Airworthiness Directives; Robinson Helicopter Company Model R44
Helicopters
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment adopts a new airworthiness directive (AD) for
Robinson Helicopter Company (RHC) Model R44 helicopters that requires
inspecting the tail rotor pitch control assembly for roughness or
binding of the pitch control bearings (bearings) by hand-rotating the
pitch control bearing housing (housing). If the housing does not rotate
freely, the AD requires replacing the unairworthy pitch control
assembly with an airworthy unit. This amendment is prompted by reports
of failure of the tail rotor pitch control assembly due to improperly
lubricated bearings on the RHC Model R22 helicopters. Although there
have been no reported failures on the RHC Model R44 helicopters, the
design of the tail rotor pitch control assembly makes it susceptible to
the same failures as have occurred on the Model R22 helicopters. The
actions specified by this AD are intended to detect corrosion of the
bearings and to prevent bearing failure and subsequent loss of
directional control of the helicopter.
DATES: Effective March 26, 2003.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of March 26, 2003.
ADDRESSES: The service information referenced in this AD may be
obtained from Robinson Helicopter Company, 2901 Airport Drive,
Torrance, California 90505, telephone (310) 539-0508, fax (310) 539-
5198. 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: Fred Guerin, Aviation Safety Engineer,
FAA, Los Angeles Aircraft Certification Office, Airframe Branch, 3960
Paramount Blvd., Lakewood, California 90712, telephone (562) 627-5232,
fax (562) 627-5210.
SUPPLEMENTARY INFORMATION: A proposal to amend 14 CFR part 39 to
include an AD for the specified helicopters was published in the
Federal Register on September 10, 2002 (67 FR 57351). That action
proposed inspecting the pitch control assembly for roughness or binding
of the bearings by hand-rotating the housing and if the housing does
not rotate freely, replacing each unairworthy pitch control assembly
with an airworthy unit.
The FAA has reviewed RHC Service Bulletin SB-43A, Revision A, dated
June 10, 2002 (SB), which describes procedures for inspecting the pitch
control assembly for roughness or binding of the bearings by hand-
rotating the housing. If the housing does not rotate freely, the SB
specifies replacing each unairworthy pitch control assembly, part
number (P/N) A031-1, with an airworthy unit in accordance with the
maintenance manual.
Interested persons have been afforded an opportunity to participate
in the making of this amendment. Due consideration has been given to
the comments received.
One commenter, the manufacturer, requests a change to the summary
information to indicate that bearing failures have been reported only
on RHC Model R22 helicopters, and there are no reports of failed
bearings on Model R44 helicopters. The FAA agrees and has changed the
preamble information to indicate that the bearing failures have
occurred on the RHC Model R22 helicopters only.
The same commenter requests a change to the summary and the
discussion sections to revise the failure sequence to indicate that
bearing failure could result in loss of tail rotor thrust requiring a
power-off landing. The commenter states that in all three of the
bearing failures, the failed bearing caused the pitch control linkage
to fail and the tail rotor to go to flat pitch but none of the failures
resulted in an accident. The commenter also states that there was no
breakup of the tail rotor assembly, no tail rotor contact of the
tailboom, and no loss of control resulting in an accident. The FAA
agrees that the failed bearing has not resulted in breakup of the tail
rotor assembly and contact with the tailboom, and the likelihood of
such a breakup and contact with the tailboom may be remote. Therefore,
we have removed the reference to the breakup of the tail rotor assembly
and contact with the tailboom from the failure sequence. We do not
agree that the failure sequence should state that bearing failure could
result in loss of tail rotor thrust requiring a power-off landing. The
loss of directional control associated with this type of failure could
result in loss of control of the helicopter, and a successful power-off
landing may not be possible. The term ``loss of control of the
helicopter'', however, may be understood to mean an almost certain
catastrophic event, such as loss of cyclic or pitch control. That is
not our intent when we use the failure sequence in our AD's. That
sequence states what could happen not necessarily what will happen. Our
intent is to convey the sequence of events that we intend to prevent by
issuing the AD to correct the unsafe condition. Therefore, we have
changed the failure sequence to state that loss of ``directional''
control can result.
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 with the changes
described previously. The FAA has determined that these changes will
neither increase the economic burden on any operator nor increase the
scope of the AD.
The FAA estimates that this AD will affect 440 helicopters of U.S.
registry, that it will take approximately 2.3 work hours per helicopter
to inspect and replace each pitch control assembly, and that the
average labor rate is $60 per
[[Page 7911]]
work hour. Required parts will cost approximately $1145 per helicopter.
Based on these figures, the total cost impact of the AD on U.S.
operators is estimated to be $564,520, assuming the pitch control
assembly is replaced on 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:
2003-04-05 Robinson Helicopter Company: Amendment 39-13053. Docket
No. 2001-SW-45-AD.
Applicability: Model R44 helicopters, up to and including serial
number 1208, except serial numbers 1143, 1165, 1183, 1189, 1192,
1196, 1197, 1198, 1200, 1203, and 1204, with pitch control assembly,
part number (P/N) C031-1, Revision G or prior, 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 (b) 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 detect corrosion of a tail rotor pitch control bearing
(bearing) and to prevent bearing failure and subsequent loss of
directional control of the helicopter, accomplish the following:
(a) Within 20 hours time-in-service (TIS) and thereafter at
intervals not to exceed 300 hours TIS or 12 months, whichever occurs
first, inspect the pitch control assembly for roughness or binding
of the pitch control bearings by hand rotating the pitch control
bearing housing (housing) in accordance with Robinson Helicopter
Company Service Bulletin SB-43A, Revision A, dated June 10, 2002. If
the housing does not rotate freely, before further flight, replace
the unairworthy pitch control assembly with an airworthy unit.
(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, Los Angeles Aircraft Certification
Office (LAACO), FAA. Operators shall submit their requests through
an FAA Principal Maintenance Inspector, who may concur or comment
and then send it to the Manager, LAACO.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the LAACO.
(c) Special flight permits may be issued in accordance with 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 inspection of the pitch control assembly shall be done
in accordance with Robinson Helicopter Company Service Bulletin SB-
43A, Revision A, dated June 10, 2002. 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 Robinson Helicopter Company, 2901 Airport Drive,
Torrance, California 90505, telephone (310) 539-0508, fax (310) 539-
5198. 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 March 26, 2003.
Issued in Fort Worth, Texas, on February 6, 2003.
David A. Downey,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 03-3773 Filed 2-18-03; 8:45 am]
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