Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76A, B, and C Helicopters, 61721-61723 [05-21256]
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61721
Federal Register / Vol. 70, No. 206 / Wednesday, October 26, 2005 / Rules and Regulations
(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.
We prepared a regulatory evaluation
of the estimated costs to comply with
this AD and placed it in the AD docket.
See the ADDRESSES section for a location
to examine the regulatory evaluation.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation
safety, Incorporation by reference,
Safety.
Adoption of the Amendment
Accordingly, under the authority
delegated to me by the Administrator,
the FAA amends 14 CFR part 39 as
follows:
I
PART 39—AIRWORTHINESS
DIRECTIVES
1. The authority citation for part 39
continues to read as follows:
I
Authority: 49 U.S.C. 106(g), 40113, 44701.
§ 39.13
[Amended]
2. The Federal Aviation
Administration (FAA) amends § 39.13
by adding the following new
airworthiness directive (AD):
I
2005–22–05 Airbus: Amendment 39–14349.
Docket No. FAA–2005–22170;
Directorate Identifier 2005–NM–073–AD.
Effective Date
(a) This AD becomes effective November
30, 2005.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Airbus Model A320–
111, –211, –212, and –231 airplanes,
certificated in any category, that have not
received Airbus Modification 21088 or 21999
in production; and airplanes that have
received Airbus Modification 21088 in
production and have manufacturer’s serial
numbers 91 to 113 inclusive and 140 to 189
inclusive.
Unsafe Condition
(d) This AD results from fuel systems
reviews conducted by the manufacturer. We
are issuing this AD to prevent chafing of the
fuel pump cables, which could result in
electrical arcing and possible ignition of fuel
vapors and consequent explosion of the fuel
tank.
Compliance
(e) You are responsible for having the
actions required by this AD performed within
the compliance times specified, unless the
actions have already been done.
VerDate Aug<31>2005
14:58 Oct 25, 2005
Jkt 208001
Inspection and Modification of Fuel Pump
Access Holes
(f) Within 58 months after the effective
date of this AD, perform the actions required
by paragraph (f)(1) or (f)(2) of this AD, as
applicable.
(1) For airplanes that have not received
Airbus Modification 21088 or 21999 in
production: Modify the cables and access
holes to the inner tank fuel pumps, in
accordance with the Accomplishment
Instructions of Airbus Service Bulletin A320–
28–1008, Revision 1, dated April 10, 1989.
(2) For airplanes that have received Airbus
Modification 21088 in production and have
manufacturer’s serial numbers 91 to 113
inclusive and 140 to 189 inclusive: Perform
a general visual inspection for the correct
radius of the fuel pump access holes and
modify the access holes, as applicable, in
accordance with the Accomplishment
Instructions of Airbus Service Bulletin A320–
28–1054, dated August 23, 1993. Do any
applicable repairs before further flight.
Note 1: For the purposes of this AD, a
general visual inspection is: ‘‘A visual
examination of an interior or exterior area,
installation, or assembly to detect obvious
damage, failure, or irregularity. This level of
inspection is made from within touching
distance unless otherwise specified. A mirror
may be necessary to ensure visual access to
all surfaces in the inspection area. This level
of inspection is made under normally
available lighting conditions such as
daylight, hangar lighting, flashlight, or
droplight and may require removal or
opening of access panels or doors. Stands,
ladders, or platforms may be required to gain
proximity to the area being checked.’’
No Reporting Requirement
(g) Although Airbus Service Bulletin
A320–28–1054, dated August 23, 1993,
describes procedures for reporting inspection
findings to Airbus, this AD does not require
that report.
Alternative Methods of Compliance
(AMOCs)
(h)(1) The Manager, International Branch,
ANM–116, Transport Airplane Directorate,
FAA, has the authority to approve AMOCs
for this AD, if requested in accordance with
the procedures found in 14 CFR 39.19.
(2) Before using any AMOC approved in
accordance with § 39.19 on any airplane to
which the AMOC applies, notify the
appropriate principal inspector in the FAA
Flight Standards Certificate Holding District
Office.
Related Information
(i) French airworthiness directive F–2005–
031, dated February 16, 2005, also addresses
the subject of this AD.
Material Incorporated by Reference
(j) You must use the service information
identified in Table 1 of this AD to perform
the actions that are required by this AD,
unless the AD specifies otherwise. Airbus
Service Bulletin A320–28–1008, Revision 1,
dated April 10, 1989, contains the following
effective pages:
PO 00000
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Fmt 4700
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Page No.
Revision level
shown on
page
Date
shown on
page
1, 2, 7–9 .......
1 ...................
3–6 ...............
Original ........
April 10,
1989.
February 9,
1989.
The Director of the Federal Register
approved the incorporation by reference of
these documents in accordance with 5 U.S.C.
552(a) and 1 CFR part 51. Contact Airbus, 1
Rond Point Maurice Bellonte, 31707 Blagnac
Cedex, France, for a copy of this service
information. You may review copies at the
Docket Management Facility, U.S.
Department of Transportation, 400 Seventh
Street SW., room PL–401, Nassif Building,
Washington, DC; on the Internet at https://
dms.dot.gov; or at the National Archives and
Records Administration (NARA). For
information on the availability of this
material at the NARA, call (202) 741–6030,
or go to https://www.archives.gov/
federal_register/code_of_federal_regulations/
ibr_locations.html.
Airbus service
bulletin
Revision level
A320–28–
1008.
A320–28–
1054.
1 ...................
Original ........
Date
April 10,
1989.
August 23,
1993.
Issued in Renton, Washington, on October
18, 2005.
Kevin M. Mullin,
Acting Manager, Transport Airplane
Directorate, Aircraft Certification Service.
[FR Doc. 05–21312 Filed 10–25–05; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2005–22757; Directorate
Identifier 2005–SW–32–AD; Amendment 39–
14345; AD 2005–22–01]
RIN 2120–AA64
Airworthiness Directives; Sikorsky
Aircraft Corporation Model S–76A, B,
and C Helicopters
Federal Aviation
Administration, DOT.
ACTION: Final rule; request for
comments.
AGENCY:
SUMMARY: This amendment adopts a
new airworthiness directive (AD) for the
Sikorsky Aircraft Corporation (Sikorsky)
Model S–76A, B, and C helicopters.
This action requires certain inspections
of the main rotor lower bifilar arm
assembly in the attachment area around
the lower bifilar lugs for a crack. If a
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Federal Register / Vol. 70, No. 206 / Wednesday, October 26, 2005 / Rules and Regulations
crack is found on any bifilar lug, this
AD requires replacing the bifilar arm
assembly with an airworthy bifilar arm
assembly. If no crack is found, this AD
requires a one-time test for the required
torque on the lug nuts and, if necessary,
applying the required torque and
conducting the torque stabilization tests.
This amendment is prompted by four
reports of cracked bifilars. The actions
specified in this AD are intended to
prevent failure of a bifilar lug, damage
to the main rotor control system, and
subsequent loss of control of the
helicopter.
DATES: Effective November 10, 2005.
The incorporation by reference of
certain publications listed in the
regulations is approved by the Director
of the Federal Register as of November
10, 2005.
Comments for inclusion in the Rules
Docket must be received on or before
December 27, 2005.
ADDRESSES: Use one of the following
addresses to submit comments on this
AD:
• DOT Docket Web site: Go to
https://dms.dot.gov and follow the
instructions for sending your comments
electronically;
• Government-wide rulemaking Web
site: Go to https://www.regulations.gov
and follow the instructions for sending
your comments electronically;
• Mail: Docket Management Facility;
U.S. Department of Transportation, 400
Seventh Street SW., Nassif Building,
Room PL–401, Washington, DC 20590;
• Fax: (202) 493–2251; or
• Hand Delivery: Room PL–401 on
the plaza level of the Nassif Building,
400 Seventh Street SW., Washington,
DC, between 9 a.m. and 5 p.m., Monday
through Friday, except Federal holidays.
You may get the service information
identified in this AD from Sikorsky
Aircraft Corporation, Attn: Manager,
Commercial Tech Support, 6900 Main
Street, Stratford, Connecticut 06614,
phone (203) 386–3001, fax (203) 386–
5983.
Examining the Docket
You may examine the docket that
contains the AD, any comments, and
other information on the Internet at
https://dms.dot.gov, or in person at the
Docket Management System (DMS)
Docket Offices between 9 a.m. and 5
p.m., Monday through Friday, except
Federal holidays. The Docket Office
(telephone (800) 647–5227) is located on
the plaza level of the Department of
Transportation Nassif Building at the
street address stated in the ADDRESSES
section. Comments will be available in
the AD docket shortly after the DMS
receives them.
VerDate Aug<31>2005
14:58 Oct 25, 2005
Jkt 208001
FOR FURTHER INFORMATION CONTACT:
Tracy Murphy, Aviation Safety
Engineer, Boston Aircraft Certification
Office, 12 New England Executive Park,
Burlington, MA 01803, telephone (781)
238–7172, fax (781) 238–7170.
SUPPLEMENTARY INFORMATION: This
amendment adopts a new AD for
Sikorsky Model S–76A, B, and C
helicopters. This action requires certain
inspections of the main rotor lower
bifilar arm assembly around the lower
bifilar lugs for a crack. If a crack is
found on any bifilar lug, this AD
requires replacing the bifilar arm
assembly with an airworthy bifilar arm
assembly. If no crack is found, this AD
requires a one-time test for the required
torque on the lug nuts and, if necessary,
applying the required torque and
conducting the torque stabilization tests.
This amendment is prompted by four
reports of cracked bifilars. The actions
specified in this AD are intended to
prevent failure of a bifilar lug, damage
to the main rotor system, and
subsequent loss of control of the
helicopter.
Sikorsky issued Alert Service Bulletin
No. 76–65–62, dated December 14, 2004
(ASB), after receiving two reports of
cracks in the lug areas of helicopters.
Sikorsky states that cracked lugs were
found despite the lower support lug
joining being torqued and stabilized. For
a bifilar with more than 1500 hours, the
ASB specifies performing, within 100
flight hours from the issue date of the
ASB, a one-time inspection of the lower
bifilar support lugs for cracks in the lug
attachment areas. These are considered
interim actions until terminating action
can be taken. Sikorsky has designed and
is currently testing a new main rotor
hub pilot fitting (pilot fitting).
Since Sikorsky issued the ASB, the
FAA has received two more reports for
a total of four reports of cracked bifilars.
The additional reports indicate that
cracks have become more severe.
Therefore, this AD will require a repeat
inspection of the arm assembly in
addition to the inspections in the ASB.
Also, this AD is effective for helicopters
with a pilot fitting, part number (P/N)
76103–08003–101, which is different
from what the ASB specifies.
Investigation has shown the root cause
of the failure is not the bifilar itself but
the mating part that attaches the bifilar
to the main rotor hub, called the pilot
fitting. This fitting is transferring the
load too abruptly into the bifilar. The
ongoing fatigue testing is with the
production bifilar and the redesigned
pilot fitting. If the tests are successful,
terminating action likely will include
installing the new pilot fitting. The
PO 00000
Frm 00010
Fmt 4700
Sfmt 4700
frequency of reports and the severity of
the failures prompted this AD. In the
most recent report, six of the six lugs
had separated from the bifilar.
This unsafe condition is likely to exist
or develop on other helicopters of these
same type designs. Therefore, this AD is
being issued to prevent failure of a
bifilar lug, damage to the main rotor
system, and subsequent loss of control
of the helicopter. This AD requires the
following for helicopters with a pilot
fitting, part number (P/N) 76103–08003–
101, with 1500 or more hours time-inservice (TIS):
• Within 50 hours TIS, unless
accomplished previously, and thereafter
at intervals not to exceed 50 hours TIS,
inspect the bifilar arm assembly for a
crack in the lug attachment area.
• If you find a crack on any bifilar
arm assembly lug, before further flight,
replace the bifilar arm assembly with an
airworthy bifilar arm assembly.
• If no crack is found at the initial
inspection, perform a one-time torque
test. The torque test is not required at
the recurring inspection intervals of the
bifilar arm assembly.
Accomplish the actions by following
the specified portions of the ASB
described previously.
The short compliance time involved
is required because the previously
described critical unsafe condition can
adversely affect the structural integrity
of the helicopter. This AD requires the
affected helicopters to be inspected and
undergo a torque test within 50 hours
TIS. If you find a crack in the bifilar lug
attachment area, this AD requires
replacing any unairworthy bifilar arm
assembly with an airworthy bifilar arm
assembly before further flight.
Therefore, 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.
We estimate that this AD will:
• Affect 216 helicopters,
• Take about 4 work hours for each
inspection (including the torque
stabilization tests), assuming 6
inspections per year, and 4 hours to
replace the bifilars, assuming a total of
2 bifilar arm assemblies need replacing,
and
• Cost about $19,727 for a bifilar arm
assembly.
Based on these figures, we estimate
the total cost impact of the AD on U.S.
operators to be $376,934.
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Federal Register / Vol. 70, No. 206 / Wednesday, October 26, 2005 / Rules and Regulations
Comments Invited
This AD is a final rule that involves
requirements that affect flight safety and
was not preceded by notice and an
opportunity for public comment;
however, we invite you to submit any
written data, views, or arguments
regarding this AD. Send your comments
to an address listed under ADDRESSES.
Include ‘‘Docket No. FAA–2005–22757;
Directorate Identifier 2005–SW–32–AD’’
at the beginning of your comments. We
specifically invite comments on the
overall regulatory, economic,
environmental, and energy aspects of
the AD. We will consider all comments
received by the closing date and may
amend the AD in light of those
comments.
We will post all comments we
receive, without change, to https://
dms.dot.gov, including any personal
information you provide. We will also
post a report summarizing each
substantive verbal contact with FAA
personnel concerning this AD. Using the
search function of our docket web site,
you can find and read the comments to
any of our dockets, including the name
of the individual who sent the
comment. You may review the DOT’s
complete Privacy Act Statement in the
Federal Register published on April 11,
2000 (65 FR 19477–78), or you may visit
https://dms.dot.gov.
the FAA Administrator. Subtitle VII,
Aviation Programs, describes in more
detail the scope of the Agency’s
authority.
We are issuing this rulemaking under
the authority described in Subtitle VII,
Part A, Subpart III, Section 44701,
‘‘General requirements.’’ Under that
section, Congress charges the FAA with
promoting safe flight of civil aircraft in
air commerce by prescribing regulations
for practices, methods, and procedures
the Administrator finds necessary for
safety in air commerce. This regulation
is within the scope of that authority
because it addresses an unsafe condition
that is likely to exist or develop on
products identified in this rulemaking
action.
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:
I
PART 39—AIRWORTHINESS
DIRECTIVES
1. The authority citation for part 39
continues to read as follows:
I
Regulatory Findings
Authority: 49 U.S.C. 106(g), 40113, 44701.
We have determined that this AD will
not have federalism implications under
Executive Order 13132. This AD 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.
For the reasons discussed above, I
certify that the regulation:
1. Is not a ‘‘significant regulatory
action’’ under Executive Order 12866;
2. Is not a ‘‘significant rule’’ under the
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.
We prepared an economic evaluation
of the estimated costs to comply with
this AD. See the DMS to examine the
economic evaluation.
Authority for This Rulemaking
Title 49 of the United States Code
specifies the FAA’s authority to issue
rules on aviation safety. Subtitle I,
Section 106, describes the authority of
VerDate Aug<31>2005
14:58 Oct 25, 2005
Jkt 208001
§ 39.13
[Amended]
61723
Perform the torque test and the additional
torque procedures as stated in the
Accomplishment Instructions, paragraph
3.B.(1) through 3.B.(3) of the ASB. The torque
test is not required at the recurring
inspection intervals of the lower bifilar arm
assembly.
(b) To request a different method of
compliance or a different compliance time
for this AD, follow the procedures in 14 CFR
39.19. Contact the Boston Aircraft
Certification Office, FAA, for information
about previously approved alternative
methods of compliance.
(c) Inspect the lower bifilar arm assembly
and perform the torque test by following the
specified portions of Sikorsky Alert Service
Bulletin No. 76–65–62, dated December 14,
2004. The Director of the Federal Register
approved this incorporation by reference in
accordance with 5 U.S.C. 552(a) and 1 CFR
part 51. Copies may be obtained from
Sikorsky Aircraft Corporation, Attn: Manager,
Commercial Tech Support, 6900 Main Street,
Stratford, Connecticut 06614, phone (203)
386–3001, fax (203) 386–5983. Copies may be
inspected at the National Archives and
Records Administration (NARA). For
information on the availability of this
material at NARA, call 202–741–6030, or go
to: https://www.archives.gov/federal_register/
code_of_federal_regulations/
ibr_locations.html.
(d) This amendment becomes effective on
November 10, 2005.
Issued in Fort Worth, Texas, on October 17,
2005.
David A. Downey,
Manager, Rotorcraft Directorate, Aircraft
Certification Service.
[FR Doc. 05–21256 Filed 10–25–05; 8:45 am]
BILLING CODE 4910–13–P
2. Section 39.13 is amended by adding
a new airworthiness directive to read as
follows:
I
2005–22–01 Sikorsky Aircraft Corporation:
Amendment 39–14345. Docket No.
FAA–2005–22757; Directorate Identifier
2005–SW–32–AD.
Applicability: Model S–76A, B, and C, with
a main rotor hub pilot fitting (pilot fitting),
part number (P/N) 76103–08003–101, with
1500 or more hours time-in-service (TIS),
installed, certificated in any category.
Compliance: Required as indicated.
To prevent failure of a bifilar lug, damage
to the main rotor system, and subsequent loss
of control of the helicopter, accomplish the
following:
(a) Within 50 hours TIS, and thereafter at
intervals not to exceed 50 hours TIS, inspect
the lower bifilar arm assembly for a crack in
the lug attachment area. Conduct the
inspection of the lower bifilar arm assembly
by following the Accomplishment
Instructions, paragraph 3.A.(1) through
3.A.(6), of Sikorsky Alert Service Bulletin No.
76–65–62, dated December 14, 2004 (ASB).
(1) If you find a crack on any bifilar arm
assembly lug, before further flight, replace
the bifilar arm assembly with an airworthy
bifilar arm assembly.
(2) If no crack is found at the initial
inspection, perform a one-time torque test.
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Fmt 4700
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2005–22018; Directorate
Identifier 2005–CE–41–AD; Amendment 39–
14348; AD 2005–22–04]
RIN 2120–AA64
Airworthiness Directives; Pilatus
Aircraft Ltd. Models PC–12 and PC–12/
45 Airplanes
Federal Aviation
Administration (FAA), DOT.
ACTION: Final rule.
AGENCY:
SUMMARY: The FAA adopts a new
airworthiness directive (AD) for certain
Pilatus Aircraft Ltd. (Pilatus) Models
PC–12 and PC–12/45 airplanes. This AD
requires you to determine (maintenance
records check and/or inspection)
whether certain nose landing gear
(NLG), main landing gear (MLG), and
MLG shock absorber assemblies with a
serial number beginning with ‘‘AM’’ are
E:\FR\FM\26OCR1.SGM
26OCR1
]]>Agencies
[Federal Register Volume 70, Number 206 (Wednesday, October 26, 2005)]
[Rules and Regulations]
[Pages 61721-61723]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-21256]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2005-22757; Directorate Identifier 2005-SW-32-AD;
Amendment 39-14345; AD 2005-22-01]
RIN 2120-AA64
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-
76A, B, and C Helicopters
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
-----------------------------------------------------------------------
SUMMARY: This amendment adopts a new airworthiness directive (AD) for
the Sikorsky Aircraft Corporation (Sikorsky) Model S-76A, B, and C
helicopters. This action requires certain inspections of the main rotor
lower bifilar arm assembly in the attachment area around the lower
bifilar lugs for a crack. If a
[[Page 61722]]
crack is found on any bifilar lug, this AD requires replacing the
bifilar arm assembly with an airworthy bifilar arm assembly. If no
crack is found, this AD requires a one-time test for the required
torque on the lug nuts and, if necessary, applying the required torque
and conducting the torque stabilization tests. This amendment is
prompted by four reports of cracked bifilars. The actions specified in
this AD are intended to prevent failure of a bifilar lug, damage to the
main rotor control system, and subsequent loss of control of the
helicopter.
DATES: Effective November 10, 2005.
The incorporation by reference of certain publications listed in
the regulations is approved by the Director of the Federal Register as
of November 10, 2005.
Comments for inclusion in the Rules Docket must be received on or
before December 27, 2005.
ADDRESSES: Use one of the following addresses to submit comments on
this AD:
DOT Docket Web site: Go to https://dms.dot.gov and follow
the instructions for sending your comments electronically;
Government-wide rulemaking Web site: Go to https://
www.regulations.gov and follow the instructions for sending your
comments electronically;
Mail: Docket Management Facility; U.S. Department of
Transportation, 400 Seventh Street SW., Nassif Building, Room PL-401,
Washington, DC 20590;
Fax: (202) 493-2251; or
Hand Delivery: Room PL-401 on the plaza level of the
Nassif Building, 400 Seventh Street SW., Washington, DC, between 9 a.m.
and 5 p.m., Monday through Friday, except Federal holidays. You may get
the service information identified in this AD from Sikorsky Aircraft
Corporation, Attn: Manager, Commercial Tech Support, 6900 Main Street,
Stratford, Connecticut 06614, phone (203) 386-3001, fax (203) 386-5983.
Examining the Docket
You may examine the docket that contains the AD, any comments, and
other information on the Internet at https://dms.dot.gov, or in person
at the Docket Management System (DMS) Docket Offices between 9 a.m. and
5 p.m., Monday through Friday, except Federal holidays. The Docket
Office (telephone (800) 647-5227) is located on the plaza level of the
Department of Transportation Nassif Building at the street address
stated in the ADDRESSES section. Comments will be available in the AD
docket shortly after the DMS receives them.
FOR FURTHER INFORMATION CONTACT: Tracy Murphy, Aviation Safety
Engineer, Boston Aircraft Certification Office, 12 New England
Executive Park, Burlington, MA 01803, telephone (781) 238-7172, fax
(781) 238-7170.
SUPPLEMENTARY INFORMATION: This amendment adopts a new AD for Sikorsky
Model S-76A, B, and C helicopters. This action requires certain
inspections of the main rotor lower bifilar arm assembly around the
lower bifilar lugs for a crack. If a crack is found on any bifilar lug,
this AD requires replacing the bifilar arm assembly with an airworthy
bifilar arm assembly. If no crack is found, this AD requires a one-time
test for the required torque on the lug nuts and, if necessary,
applying the required torque and conducting the torque stabilization
tests. This amendment is prompted by four reports of cracked bifilars.
The actions specified in this AD are intended to prevent failure of a
bifilar lug, damage to the main rotor system, and subsequent loss of
control of the helicopter.
Sikorsky issued Alert Service Bulletin No. 76-65-62, dated December
14, 2004 (ASB), after receiving two reports of cracks in the lug areas
of helicopters. Sikorsky states that cracked lugs were found despite
the lower support lug joining being torqued and stabilized. For a
bifilar with more than 1500 hours, the ASB specifies performing, within
100 flight hours from the issue date of the ASB, a one-time inspection
of the lower bifilar support lugs for cracks in the lug attachment
areas. These are considered interim actions until terminating action
can be taken. Sikorsky has designed and is currently testing a new main
rotor hub pilot fitting (pilot fitting).
Since Sikorsky issued the ASB, the FAA has received two more
reports for a total of four reports of cracked bifilars. The additional
reports indicate that cracks have become more severe. Therefore, this
AD will require a repeat inspection of the arm assembly in addition to
the inspections in the ASB. Also, this AD is effective for helicopters
with a pilot fitting, part number (P/N) 76103-08003-101, which is
different from what the ASB specifies. Investigation has shown the root
cause of the failure is not the bifilar itself but the mating part that
attaches the bifilar to the main rotor hub, called the pilot fitting.
This fitting is transferring the load too abruptly into the bifilar.
The ongoing fatigue testing is with the production bifilar and the
redesigned pilot fitting. If the tests are successful, terminating
action likely will include installing the new pilot fitting. The
frequency of reports and the severity of the failures prompted this AD.
In the most recent report, six of the six lugs had separated from the
bifilar.
This unsafe condition is likely to exist or develop on other
helicopters of these same type designs. Therefore, this AD is being
issued to prevent failure of a bifilar lug, damage to the main rotor
system, and subsequent loss of control of the helicopter. This AD
requires the following for helicopters with a pilot fitting, part
number (P/N) 76103-08003-101, with 1500 or more hours time-in-service
(TIS):
Within 50 hours TIS, unless accomplished previously, and
thereafter at intervals not to exceed 50 hours TIS, inspect the bifilar
arm assembly for a crack in the lug attachment area.
If you find a crack on any bifilar arm assembly lug,
before further flight, replace the bifilar arm assembly with an
airworthy bifilar arm assembly.
If no crack is found at the initial inspection, perform a
one-time torque test. The torque test is not required at the recurring
inspection intervals of the bifilar arm assembly.
Accomplish the actions by following the specified portions of the
ASB described previously.
The short compliance time involved is required because the
previously described critical unsafe condition can adversely affect the
structural integrity of the helicopter. This AD requires the affected
helicopters to be inspected and undergo a torque test within 50 hours
TIS. If you find a crack in the bifilar lug attachment area, this AD
requires replacing any unairworthy bifilar arm assembly with an
airworthy bifilar arm assembly before further flight. Therefore, 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.
We estimate that this AD will:
Affect 216 helicopters,
Take about 4 work hours for each inspection (including the
torque stabilization tests), assuming 6 inspections per year, and 4
hours to replace the bifilars, assuming a total of 2 bifilar arm
assemblies need replacing, and
Cost about $19,727 for a bifilar arm assembly.
Based on these figures, we estimate the total cost impact of the AD
on U.S. operators to be $376,934.
[[Page 61723]]
Comments Invited
This AD is a final rule that involves requirements that affect
flight safety and was not preceded by notice and an opportunity for
public comment; however, we invite you to submit any written data,
views, or arguments regarding this AD. Send your comments to an address
listed under ADDRESSES. Include ``Docket No. FAA-2005-22757;
Directorate Identifier 2005-SW-32-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of the AD. We will consider
all comments received by the closing date and may amend the AD in light
of those comments.
We will post all comments we receive, without change, to https://
dms.dot.gov, including any personal information you provide. We will
also post a report summarizing each substantive verbal contact with FAA
personnel concerning this AD. Using the search function of our docket
web site, you can find and read the comments to any of our dockets,
including the name of the individual who sent the comment. You may
review the DOT's complete Privacy Act Statement in the Federal Register
published on April 11, 2000 (65 FR 19477-78), or you may visit https://
dms.dot.gov.
Regulatory Findings
We have determined that this AD will not have federalism
implications under Executive Order 13132. This AD 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.
For the reasons discussed above, I certify that the regulation:
1. Is not a ``significant regulatory action'' under Executive Order
12866;
2. Is not a ``significant rule'' under the 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.
We prepared an economic evaluation of the estimated costs to comply
with this AD. See the DMS to examine the economic evaluation.
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, Section 106, describes the
authority of the FAA Administrator. Subtitle VII, Aviation Programs,
describes in more detail the scope of the Agency's authority.
We are issuing this rulemaking under the authority described in
Subtitle VII, Part A, Subpart III, Section 44701, ``General
requirements.'' Under that section, Congress charges the FAA with
promoting safe flight of civil aircraft in air commerce by prescribing
regulations for practices, methods, and procedures the Administrator
finds necessary for safety in air commerce. This regulation is within
the scope of that authority because it addresses an unsafe condition
that is likely to exist or develop on products identified in this
rulemaking action.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
0
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
0
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]
0
2. Section 39.13 is amended by adding a new airworthiness directive to
read as follows:
2005-22-01 Sikorsky Aircraft Corporation: Amendment 39-14345. Docket
No. FAA-2005-22757; Directorate Identifier 2005-SW-32-AD.
Applicability: Model S-76A, B, and C, with a main rotor hub
pilot fitting (pilot fitting), part number (P/N) 76103-08003-101,
with 1500 or more hours time-in-service (TIS), installed,
certificated in any category.
Compliance: Required as indicated.
To prevent failure of a bifilar lug, damage to the main rotor
system, and subsequent loss of control of the helicopter, accomplish
the following:
(a) Within 50 hours TIS, and thereafter at intervals not to
exceed 50 hours TIS, inspect the lower bifilar arm assembly for a
crack in the lug attachment area. Conduct the inspection of the
lower bifilar arm assembly by following the Accomplishment
Instructions, paragraph 3.A.(1) through 3.A.(6), of Sikorsky Alert
Service Bulletin No. 76-65-62, dated December 14, 2004 (ASB).
(1) If you find a crack on any bifilar arm assembly lug, before
further flight, replace the bifilar arm assembly with an airworthy
bifilar arm assembly.
(2) If no crack is found at the initial inspection, perform a
one-time torque test. Perform the torque test and the additional
torque procedures as stated in the Accomplishment Instructions,
paragraph 3.B.(1) through 3.B.(3) of the ASB. The torque test is not
required at the recurring inspection intervals of the lower bifilar
arm assembly.
(b) To request a different method of compliance or a different
compliance time for this AD, follow the procedures in 14 CFR 39.19.
Contact the Boston Aircraft Certification Office, FAA, for
information about previously approved alternative methods of
compliance.
(c) Inspect the lower bifilar arm assembly and perform the
torque test by following the specified portions of Sikorsky Alert
Service Bulletin No. 76-65-62, dated December 14, 2004. The Director
of the Federal Register approved this incorporation by reference in
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be
obtained from Sikorsky Aircraft Corporation, Attn: Manager,
Commercial Tech Support, 6900 Main Street, Stratford, Connecticut
06614, phone (203) 386-3001, fax (203) 386-5983. Copies may be
inspected at the National Archives and Records Administration
(NARA). For information on the availability of this material at
NARA, call 202-741-6030, or go to: https://www.archives.gov/federal_
register/code_of_federal_regulations/ibr_locations.html.
(d) This amendment becomes effective on November 10, 2005.
Issued in Fort Worth, Texas, on October 17, 2005.
David A. Downey,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 05-21256 Filed 10-25-05; 8:45 am]
BILLING CODE 4910-13-P
