[Federal Register Volume 63, Number 65 (Monday, April 6, 1998)]
[Rules and Regulations]
[Pages 16679-16681]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-8579]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-CE-69-AD; Amendment 39-10437; AD 98-07-17]
RIN 2120-AA64
Airworthiness Directives; Twin Commander Aircraft Corporation
500, 520, 560, 680, 681, 685, 690, 695, and 720 Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule.
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SUMMARY: This amendment supersedes Airworthiness Directive (AD) 94-04-
17, which currently requires the following on Twin Commander Aircraft
Corporation (Twin Commander) 500, 520, 560, 680, 681, 685, 690, 695,
and 720 series airplanes: inspecting (one-time) the flap system for
cables with broken wires or pulleys with worn cable clips, replacing
any damaged parts, and replacing the master pulley and cable with new
parts of improved design. This AD requires inspecting all flap system
cable grooves for the correct width, inspecting all flap system pulleys
for rubbing on the support brackets, inspecting all flap pulley cable
assemblies for frayed wires, and reworking or replacing any parts with
discrepancies. This AD results from several reports of worn and frayed
flap system cables attributed to flap pulley grooves that are too
narrow. The actions specified by this AD are intended to prevent
failure of a flap system cable caused by fatigue, which could result in
loss of control of the airplane.
DATES: Effective May 29, 1998.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of May 29, 1998.
ADDRESSES: Service information that applies to this AD may be obtained
from the Twin Commander Aircraft Corporation, 19003 59th Drive, NE,
Arlington, Washington 98223-7832. This information may also be examined
at the Federal Aviation Administration (FAA), Central Region, Office of
the Regional Counsel, Attention: Rules Docket No. 97-CE-69-AD, Room
1558, 601 E. 12th Street, Kansas City, Missouri 64106; or at the Office
of the Federal Register, 800 North Capitol Street, NW, suite 700,
Washington, DC.
FOR FURTHER INFORMATION CONTACT: Mr. Jeffrey Morfitt, Aerospace
Engineer, FAA, Northwest Mountain Region, 1601
[[Page 16680]]
Lind Avenue S.W., Renton, Washington 98055-4056; telephone: (425) 227-
2595; facsimile: (425) 227-1181.
SUPPLEMENTARY INFORMATION:
Events Leading to the Issuance of This AD
A proposal to amend part 39 of the Federal Aviation Regulations (14
CFR part 39) to include an AD that would apply all models of Twin
Commander 500, 520, 560, 680, 681, 685, 690, 695, and 720 series
airplanes was published in the Federal Register as a notice of proposed
rulemaking (NPRM) on October 31, 1997 (62 FR 58925). The NPRM proposed
to supersede AD 94-04-17 with a new AD that requires inspecting all
flap system cable grooves for the correct width, inspecting all flap
system pulleys for rubbing on the support brackets, inspecting all flap
pulley cable assemblies for frayed wires, and reworking or replacing
any parts with discrepancies. Accomplishment of the proposed action as
specified in the NPRM would be in accordance with Twin Commander
Mandatory Service Bulletin No. 226, dated April 14, 1997 (Revision No.
1 Release Date: July 15, 1997).
The NPRM was the result of several reports of worn and frayed flap
system cables attributed to flap pulley grooves that are too narrow.
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.
Comment Disposition
The commenter expresses concern over the availability of the parts
necessary to comply with the proposed AD. The commenter states that, if
the proposed AD would become a final rule with the proposed compliance
time of ``within the next 100 hours time-in-service (TIS) after the
effective date of the AD'', then the commenter's fleet of the affected
airplanes would be grounded because of parts unavailability. The
commenter requests that the FAA re-examine the compliance time of the
proposed AD before issuing a final rule.
The FAA has re-examined the compliance time, checked with the
manufacturer about the availability of parts, and has determined that a
more realistic compliance time would be ``within the next 300 hours TIS
after the effective date of this AD''. The final rule reflects this
change.
The FAA's Determination
After careful review of all available information related to the
subject presented above, the FAA has determined that air safety and the
public interest require the adoption of the rule as proposed except for
the compliance time change discussed above and minor editorial
corrections. The FAA has determined that this change and these minor
corrections will not change the meaning of the AD and will not add any
additional burden upon the public than was already proposed.
Cost Impact
The FAA estimates that 1,230 airplanes in the U.S. registry will be
affected by this AD, that it will take approximately 22 workhours per
airplane to accomplish the inspection required by this AD, and that the
average labor rate is approximately $60 an hour. Based on these
figures, the total cost impact of this AD on U.S. operators is
estimated to be $1,623,600, or $1,320 per airplane. These figures only
take into account the inspection costs of this AD and do not reflect
the costs of any repairs or replacements that may be required if
discrepancies are found during the inspection. The FAA has no way of
determining how many parts will need to be repaired or replaced after
accomplishing the inspection.
Regulatory Impact
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 copy of the final evaluation prepared for this
action is contained in the Rules Docket. A copy of it may be obtained
by contacting 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 removing Airworthiness Directive
(AD) 94-04-17, Amendment 39-8837, and by adding a new AD to read as
follows:
98-07-17 Twin Commander Aircraft Corporation: Amendment 39-10437;
Docket No. 97-CE-69-AD. Supersedes AD 94-04-17, Amendment 39-8837.
Applicability: The following airplane models (all serial
numbers), certificated in any category:
500 5500-A 5500-B 5500-S 5500-U
520 5560 5560-A 5560-E 5560-F
680 680-E 680-F 680FL 680FL(P)
680FP 680T 680V 680W 681
685 690 690A 690B 690C
690D 695 695A 695B 720
Note 1: This AD applies to each airplane 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 airplanes 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 (e) 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.
[[Page 16681]]
Compliance: Required as indicated in the body of this AD, unless
already accomplished.
To prevent failure of a flap system cable caused by fatigue,
which could result in loss of control of the airplane, accomplish
the following:
(a) Within the next 300 hours time-in-service (TIS) after the
effective date of this AD, unless already accomplished, perform the
following in accordance with the ACCOMPLISHMENT INSTRUCTIONS section
of Twin Commander Aircraft Corporation (Twin Commander) Mandatory
Service Bulletin No. 226, dated April 14, 1997 (Revision No. 1
Release Date: July 15, 1997):
(1) Inspect all flap system cable grooves for the correct width;
(2) Inspect all flap system pulleys for rubbing on the support
brackets;
(3) Inspect all flap pulley cable assemblies for frayed wires;
and
(4) Mark pulleys that have been inspected and have the correct
groove radius with two parallel lines as specified in the service
bulletin.
Note 2: Revision No. 1 Release Date: July 15, 1997, of Twin
Commander Mandatory Service Bulletin No. 226, specifies changes in
the workhours necessary to accomplish this action and makes
reference to a gauge that is available from the manufacturer for use
in accomplishing the inspection.
(b) If any of the above discrepancies are found, prior to
further flight after the inspections required by paragraph (a),
including all subparagraphs, of this AD, rework or replace the
affected part in accordance with Twin Commander Mandatory Service
Bulletin No. 226, dated April 14, 1997 (Revision No. 1 Release Date:
July 15, 1997).
(c) As of the effective date of this AD, no person may install a
pulley that does not have the criteria presented in either paragraph
(c)(1), (c)(2), or (c)(3) of this AD:
(1) A pulley that has been inspected, found acceptable, and
marked with two parallel lines in accordance with paragraph (a),
including all subparagraphs, of this AD;
(2) A pulley that has been reworked in accordance with an FAA-
approved procedure and is marked ``SB 226''; or
(3) A new pulley that is marked ``SB 226-NEW''.
(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 airplane to a location where
the requirements of this AD can be accomplished.
(e) An alternative method of compliance or adjustment of the
compliance time that provides an equivalent level of safety may be
approved by the Manager, Seattle Aircraft Certification Office
(ACO), Northwest Mountain Region, FAA, 1601 Lind Avenue S.W.,
Renton, Washington 98055-4056.
(1) The request shall be forwarded through an appropriate FAA
Maintenance Inspector, who may add comments and then send it to the
Manager, Seattle ACO.
(2) Alternative methods of compliance approved in accordance
with AD 94-04-17 (superseded by this AD) are not considered approved
as alternative methods of compliance for this AD.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the Seattle ACO.
(f) The inspections and replacements required by this AD shall
be done in accordance with Twin Commander Mandatory Service Bulletin
No. 226, dated April 14, 1997 (Revision No. 1 Release Date: July 15,
1997). 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 the Twin Commander Aircraft
Corporation, 19003 59th Drive, NE, Arlington, Washington 98223-7832.
Copies may be inspected at the FAA, Central Region, Office of the
Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City,
Missouri, or at the Office of the Federal Register, 800 North
Capitol Street, NW, suite 700, Washington, DC.
(g) This amendment supersedes AD 94-04-17, Amendment 39-8837.
(h) This amendment becomes effective on May 29, 1998.
Issued in Kansas City, Missouri, on March 24, 1998.
Carolanne L. Cabrini,
Acting Manager, Small Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 98-8579 Filed 4-3-98; 8:45 am]
BILLING CODE 4910-13-U
