Airworthiness Directives; Sikorsky Aircraft Corporation Model S-76A, S-76B, and S-76C Helicopters, 31780-31782 [E8-12414]
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31780
§ 130.30
fees.
Federal Register / Vol. 73, No. 108 / Wednesday, June 4, 2008 / Proposed Rules
Hourly rate and minimum user
(a) * * *
User fee
Oct. 1, 2008–
Sept. 30, 2009
Oct. 1, 2009–
Sept. 30, 2010
Oct. 1, 2010–
Sept. 30, 2011
Oct. 1, 2011–
Sept. 30, 2012
$120.00
30.00
35.00
$120.00
30.00
36.00
$124.00
31.00
37.00
$128.00
32.00
39.00
Hourly rate:
Per hour ........................................................................
Per quarter hour ...................................................................
Per service minimum fee .....................................................
*
*
*
*
*
Beginning
Oct. 1, 2012
$132.00
33.00
40.00
(b) * * *
Premium rate user fee
Overtime rates
(outside the employee’s normal tour of duty)
Oct. 1, 2008–
Sept. 30, 2009
Oct. 1, 2009–
Sept. 30, 2010
Oct. 1, 2010–
Sept. 30, 2011
Oct. 1, 2011–
Sept. 30, 2012
$140.00
35.00
$144.00
36.00
$148.00
37.00
$152.00
38.00
$156.00
39.00
160.00
40.00
164.00
41.00
168.00
42.00
172.00
43.00
176.00
44.00
Premium hourly rate Monday through Saturday and holidays:
Per hour ........................................................................
Per quarter hour ...........................................................
Premium hourly rate for Sundays:
Per hour ........................................................................
Per quarter hour ...........................................................
*
*
*
*
*
Done in Washington, DC, this 23rd day of
May, 2008.
Bruce Knight,
Under Secretary for Marketing and Regulatory
Programs.
[FR Doc. E8–12376 Filed 6–3–08; 8:45 am]
BILLING CODE 3410–34–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2008–0609; Directorate
Identifier 2008–SW–24–AD]
RIN 2120–AA64
Airworthiness Directives; Sikorsky
Aircraft Corporation Model S–76A,
S–76B, and S–76C Helicopters
Federal Aviation
Administration, DOT.
ACTION: Notice of proposed rulemaking
(NPRM).
rwilkins on PROD1PC63 with PROPOSALS
SUMMARY: This document proposes
adopting a new airworthiness directive
(AD) for Sikorsky Aircraft Corporation
(Sikorsky) Model S–76A, S–76B, and S–
76C helicopters. The AD would require
an initial and recurring inspections of
the tail rotor vertical stabilizer aft spar
assembly (aft spar assembly) for a crack,
loose or working fasteners, and
corrosion, and, if any are found, further
inspections of the vertical stabilizer
16:40 Jun 03, 2008
Jkt 214001
Comments must be received on
or before August 4, 2008.
ADDRESSES: Use one of the following
addresses to submit comments on this
proposed AD:
• Federal eRulemaking Portal: Go to
https://www.regulations.gov. Follow the
instructions for submitting comments.
• Fax: 202–493–2251.
• Mail: U.S. Department of
Transportation, Docket Operations, M–
30, West Building Ground Floor, Room
W12–140, 1200 New Jersey Avenue, SE.,
Washington, DC 20590.
• Hand Delivery: U.S. Department of
Transportation, Docket Operations, M–
30, West Building Ground Floor, Room
W12–140, 1200 New Jersey Avenue, SE.,
DATES:
AGENCY:
VerDate Aug<31>2005
forward spar assembly (forward spar
assembly). Repairing or replacing any
unairworthy part before further flight
would also be required. The action
would also require a recurring trackand-balance of the tail rotor. Finally, the
proposed AD would require installing a
vertical stabilizer modification kit,
which would be terminating action for
the requirements of the AD. This
proposal is prompted by 26 reports of
fatigue cracks in the aft spar assembly
web and outer caps. The actions
specified by the proposed AD are
intended to detect and correct an
unbalanced or out-of-track tail rotor,
which could lead to increased
vibrations, a fatigue crack, loss of a
portion of the vertical stabilizer and
subsequent loss of control of the
helicopter.
PO 00000
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Fmt 4702
Sfmt 4702
Beginning
Oct. 1, 2012
Washington, DC 20590, between 9 a.m.
and 5 p.m., Monday through Friday,
except Federal holidays.
You may get the service information
identified in this proposed AD from
Sikorsky Aircraft Corporation, Attn:
Manager, Commercial Technical
Support, Mailstop s581a, 6900 Main
Street, Stratford, Connecticut 06614,
phone (203) 383–4866, e-mail address
tsslibrary@sikorsky.com.
FOR FURTHER INFORMATION CONTACT:
Richard Noll, Aviation Safety Engineer,
Boston Aircraft Certification Office, 12
New England Executive Park,
Burlington, MA 01803, telephone (781)
238–7160, fax (781) 238–7170.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to submit any written
data, views, or arguments regarding this
proposed AD. Send your comments to
the address listed under the caption
ADDRESSES. Include the docket number
‘‘FAA–2008–0609, Directorate Identifier
2008–SW–24–AD’’ at the beginning of
your comments. We specifically invite
comments on the overall regulatory,
economic, environmental, and energy
aspects of the proposed AD. We will
consider all comments received by the
closing date and may amend the
proposed AD in light of those
comments.
We will post all comments we
receive, without change, to https://
www.regulations.gov, including any
personal information you provide. We
E:\FR\FM\04JNP1.SGM
04JNP1
Federal Register / Vol. 73, No. 108 / Wednesday, June 4, 2008 / Proposed Rules
will also post a report summarizing each
substantive verbal contact with FAA
personnel concerning this proposed
rulemaking. Using the search function
of the docket Web site, you can find and
read the comments to any of our
dockets, and if provided, the name of
the individual who sent or signed the
comment. You may review the DOT’s
complete Privacy Act Statement in the
Federal Register published on April 11,
2000 (65 FR 19477).
Examining the Docket
You may examine the docket that
contains the proposed AD, any
comments, and other information in
person at the Docket Operations office
between 9 a.m. and 5 p.m., Monday
through Friday, except Federal holidays.
The Docket Operations office (telephone
(800) 647–5527) is located in Room
W12–140 on the ground floor of the
West Building at the street address
stated in the ADDRESSES section.
Comments will be available in the AD
docket shortly after receipt.
Discussion
This document proposes adopting a
new AD for Sikorsky Model S–76A, S–
76B, and S–76C helicopters with any of
the following part-numbered aft spar
assemblies installed:
Helicopter model
Aft spar assembly
part No.
S–76A ...........................
76201–05002–114
76201–05002–115
76201–05002–047
76201–05002–048
76201–25002–041
76201–25002–044
76201–25002–045
76201–25002–046
rwilkins on PROD1PC63 with PROPOSALS
S–76B and S–76C ........
For any aft spar assembly having
1,000 or more hours time-in-service
(TIS), the AD would require, initially
and then at intervals not to exceed 50
hours TIS, inspecting the aft spar
assembly for a crack, a loose or working
fastener, or corrosion. If a crack, a loose
or working fastener, or corrosion is
found, repairing or replacing any
unairworthy parts and inspecting the
forward spar assembly would be
required before further flight. If that
inspection reveals a crack, a loose or
working fastener, or corrosion in the
forward spar assembly, then the damage
would have to be repaired or the parts
would need to be replaced with
airworthy parts before further flight. The
AD would also require a track-andbalance of the tail rotor within 30 days
and thereafter at intervals not to exceed
200 hours TIS. The AD would also
require, on or before December 31, 2010,
VerDate Aug<31>2005
16:40 Jun 03, 2008
Jkt 214001
installing a vertical stabilizer
modification kit, part number (P/N)
76070–20562, 76070–20563, or 76070–
20564, which would be terminating
action for the requirements of the AD.
This proposal is prompted by 26
reports of fatigue cracks in the aft spar
assembly web and outer caps since
February 1998. The actions specified in
this proposed AD are intended to detect
and correct an unbalanced or out-oftrack tail rotor, which could lead to
increased vibrations, a fatigue crack,
loss of a portion of the vertical stabilizer
and subsequent loss of control of the
helicopter.
We have reviewed the following
service information:
• Sikorsky Alert Service Bulletin
(ASB) No. 76–55–20A, Revision A,
dated November 11, 2003, that applies
to Sikorsky Model S–76A and Model S–
76C helicopters and describes
procedures for a one-time inspection of
the vertical stabilizer aft spar assembly
for cracks, loose or working fasteners,
and/or corrosion, and if necessary an
inspection of the forward spar assembly.
• ASB No. 76–65–58A, Revision A,
dated November 11, 2003, that applies
to all Sikorsky Model S–76 serial
numbered helicopters up to and
including 760526 and describes
procedures for an initial enhanced tail
rotor balance check.
This proposal would differ from those
ASBs in that the inspections described
in ASB No. 76–55–20A would be
required for the Model S–76B
helicopters as well as for the Model S–
76A and Model S–76C helicopters. Also,
the proposed AD would require
repetitive inspections of the aft spar
assembly and the forward spar
assembly, if necessary, and repetitive
tail rotor track-and-balance inspections,
whereas the two ASBs specify only a
one-time tail rotor balance check and an
aft spar assembly inspection and, if
necessary, a one-time forward spar
assembly inspection.
This unsafe condition is likely to exist
or develop on other helicopters of the
same type designs. Therefore, the
proposed AD would require, for any
spar assembly that has 1,000 or more
hours TIS, within 30 days and thereafter
at intervals not to exceed 50 hours TIS,
inspecting the aft spar assembly, and if
you find a crack, a loose or working
fastener, or corrosion, inspecting the
forward spar assembly before further
flight and replacing or repairing any
unairworthy part with an airworthy part
before further flight.
The AD would also require, within 30
days and thereafter at intervals not to
exceed 200 hours TIS, inspecting the
tail rotor track-and-balance.
PO 00000
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31781
Accomplishing the tail rotor track-andbalance inspection would involve both
a pilot and mechanic. The pilot’s
function would be to operate the
helicopter to a ‘‘light on wheels’’ state—
almost to the point of takeoff, and the
mechanic would accomplish the
vibration measurements. Also, the AD
would require, on or before December
31, 2010, installing a vertical stabilizer
modification kit, P/N 76070–20562,
76070–20563, or 76070–20564, which
would be terminating action for the
requirements of the AD. The inspections
and repairs or replacements, if
necessary, would have to be
accomplished in accordance with
specified portions of the ASBs
previously described.
We estimate that this proposed AD
would affect 216 helicopters of U.S.
registry. We also estimate that the
inspections for a crack, a loose or
working fastener, or corrosion would
take approximately 7 work hours per
helicopter to accomplish; the tail rotor
track-and-balance inspections and
adjustments would take approximately
10 work hours per helicopter; and
installing the vertical stabilizer
modification kit would take
approximately 120 hours, at an average
labor rate of $80 per work hour. The
vertical stabilizer modification kit
would cost approximately $4,250. Based
on these figures, we estimate the total
cost impact of this AD on U.S. operators
would be $4,961,520, assuming that, on
each helicopter, 12 spar assembly
inspections would be done ($1,451,520),
that 3 tail rotor track-and-balance
inspections would be done ($518,400),
that no spar assembly would need to be
repaired or replaced, and that the
vertical stabilizer modification is done.
Regulatory Findings
We have determined that this
proposed AD would not have federalism
implications under Executive Order
13132. Additionally, this proposed AD
would 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 proposed 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.
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31782
Federal Register / Vol. 73, No. 108 / Wednesday, June 4, 2008 / Proposed Rules
We prepared a draft economic
evaluation of the estimated costs to
comply with this proposed AD. See the
AD docket to examine the draft
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, Safety.
The Proposed Amendment
Accordingly, pursuant to the
authority delegated to me by the
Administrator, the Federal Aviation
Administration proposes to amend 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.
§ 39.13
[Amended]
2. Section 39.13 is amended by
adding a new airworthiness directive to
read as follows:
rwilkins on PROD1PC63 with PROPOSALS
Sikorsky Aircraft Corporation: Docket No.
FAA–2008–0609; Directorate Identifier
2008–SW–24–AD.
Applicability: Model S–76A, S–76B, and
S–76C helicopters with any of the following
part-numbered vertical stabilizer aft spars
assemblies having 1,000 or more hours timein-service (TIS) installed, certificated in any
category.
Helicopter model
S–76A ...........................
S–76B and S–76C ........
VerDate Aug<31>2005
Vertical stabilizer
aft spar assembly
part No.
76201–05002–114
76201–05002–115
76201–05002–047
16:40 Jun 03, 2008
Jkt 214001
Helicopter model
Vertical stabilizer
aft spar assembly
part No.
76201–05002–048
76201–25002–041
76201–25002–044
76201–25002–045
76201–25002–046
Compliance: Required as indicated.
To detect and correct an unbalanced or
out-of-track tail rotor, which could lead to
increased vibrations a fatigue crack, loss of a
portion of the vertical stabilizer, and
subsequent loss of control of the helicopter,
accomplish the following:
(a) Within 30 days, unless accomplished
previously, and thereafter at intervals not to
exceed 50 hours TIS, inspect the vertical
stabilizer aft spar assembly (aft spar
assembly) for a crack, a loose or working
fastener, or corrosion in accordance with the
Accomplishment Instructions, paragraph
3.A., in Sikorsky Alert Service Bulletin (ASB)
No. 76–55–20A, Revision A, dated November
11, 2003 (No. 76–55–20A). For purposes of
this AD, ASB No 76–55–20A pertains to
Model S–76B helicopters as well as Model S–
76A and S–76C helicopters.
(1) If a crack, a loose or working fastener,
or corrosion is found in the aft spar assembly,
before further flight:
(i) Repair or replace any unairworthy parts
and
(ii) Inspect the vertical stabilizer forward
spar assembly (forward spar assembly) for a
crack, a loose or working fastener, or
corrosion in accordance with the
Accomplishment Instructions, paragraph
3.B., in ASB No. 76–55–20A. Contacting the
manufacturer is not required by this AD.
(2) If a crack, a loose or working fastener,
or corrosion is found in the forward spar
assembly, repair in accordance with the
applicable maintenance manual or replace
with airworthy parts before further flight.
(b) Within 30 days, unless accomplished
previously, and thereafter at intervals not to
exceed 200 hours TIS, track-and-balance the
tail rotor in accordance with the
Accomplishment Instructions, paragraph
3.A., in ASB No. 76–65–58A, dated
November 11, 2003.
Note 1: Although the ASB specifies only an
initial inspection of the aft spar assembly and
a track-and-balance of the tail rotor, this AD
requires inspecting the aft spar assembly and
track-and-balancing the tail rotor repetitively.
Note 2: The track-and-balancing of the tail
rotor that is required by paragraph (b) of this
AD involves both a pilot and mechanic. The
pilot’s function is to operate the helicopter to
a ‘‘light on wheels’’ state—almost to the point
of takeoff. The mechanic is needed to
accomplish the vibration measurements.
(c) On or before December 31, 2010, install
a vertical stabilizer modification kit, part
number 76070–20562, 76070–20563, or
76070–20564. Installing the vertical stabilizer
modification kit is terminating action for the
requirements of this AD.
(d) To request a different method of
compliance or a different compliance time
for this AD, follow the procedures in 14 CFR
PO 00000
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Fmt 4702
Sfmt 4702
39.19. Contact the Manager, Boston Aircraft
Certification Office, Engine and Propeller
Directorate, ATTN: Richard Noll, Aviation
Safety Engineer, FAA, 12 New England
Executive Park, Burlington, MA 01803,
telephone (781) 238–7160, fax (781) 238–
7170, for information about previously
approved alternative methods of compliance.
Issued in Fort Worth, Texas, on May 22,
2008.
David A. Downey,
Manager, Rotorcraft Directorate, Aircraft
Certification Service.
[FR Doc. E8–12414 Filed 6–3–08; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF HOMELAND
SECURITY
Coast Guard
33 CFR Part 165
[Docket No. USCG–2008–0391]
RIN 1625–AA00
Safety Zone; Fireworks Display, Upper
Potomac River, Washington Channel,
Washington Harbor, DC
Coast Guard, DHS.
Notice of proposed rulemaking.
AGENCY:
ACTION:
SUMMARY: The Coast Guard proposes to
establish a temporary safety zone upon
specified waters of the Upper Potomac
River. This action is necessary to
provide for the safety of life on
navigable waters during a fireworks
display launched from a barge located
within Washington Channel, in
Washington Harbor, DC. This action
will restrict vessel traffic in a portion of
the Washington Channel.
DATES: Comments and related material
must reach the Coast Guard on or before
July 7, 2008.
ADDRESSES: You may submit comments
identified by Coast Guard docket
number USCG–2008–0391 to the Docket
Management Facility at the U.S.
Department of Transportation. To avoid
duplication, please use only one of the
following methods:
(1) Online: https://
www.regulations.gov.
(2) Mail: Docket Management Facility
(M–30), U.S. Department of
Transportation, West Building Ground
Floor, Room W12–140, 1200 New Jersey
Avenue, SE., Washington, DC 20590–
0001.
(3) Hand delivery: Room W12–140 on
the Ground Floor of the West Building,
1200 New Jersey Avenue, SE.,
Washington, DC 20590, between 9 a.m.
and 5 p.m., Monday through Friday,
except Federal holidays. The telephone
number is 202–366–9329.
E:\FR\FM\04JNP1.SGM
04JNP1
]]>Agencies
[Federal Register Volume 73, Number 108 (Wednesday, June 4, 2008)]
[Proposed Rules]
[Pages 31780-31782]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E8-12414]
=======================================================================
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2008-0609; Directorate Identifier 2008-SW-24-AD]
RIN 2120-AA64
Airworthiness Directives; Sikorsky Aircraft Corporation Model S-
76A, S-76B, and S-76C Helicopters
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
-----------------------------------------------------------------------
SUMMARY: This document proposes adopting a new airworthiness directive
(AD) for Sikorsky Aircraft Corporation (Sikorsky) Model S-76A, S-76B,
and S-76C helicopters. The AD would require an initial and recurring
inspections of the tail rotor vertical stabilizer aft spar assembly
(aft spar assembly) for a crack, loose or working fasteners, and
corrosion, and, if any are found, further inspections of the vertical
stabilizer forward spar assembly (forward spar assembly). Repairing or
replacing any unairworthy part before further flight would also be
required. The action would also require a recurring track-and-balance
of the tail rotor. Finally, the proposed AD would require installing a
vertical stabilizer modification kit, which would be terminating action
for the requirements of the AD. This proposal is prompted by 26 reports
of fatigue cracks in the aft spar assembly web and outer caps. The
actions specified by the proposed AD are intended to detect and correct
an unbalanced or out-of-track tail rotor, which could lead to increased
vibrations, a fatigue crack, loss of a portion of the vertical
stabilizer and subsequent loss of control of the helicopter.
DATES: Comments must be received on or before August 4, 2008.
ADDRESSES: Use one of the following addresses to submit comments on
this proposed AD:
Federal eRulemaking Portal: Go to https://
www.regulations.gov. Follow the instructions for submitting comments.
Fax: 202-493-2251.
Mail: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue, SE., Washington, DC 20590.
Hand Delivery: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays.
You may get the service information identified in this proposed AD
from Sikorsky Aircraft Corporation, Attn: Manager, Commercial Technical
Support, Mailstop s581a, 6900 Main Street, Stratford, Connecticut
06614, phone (203) 383-4866, e-mail address tsslibrary@sikorsky.com.
FOR FURTHER INFORMATION CONTACT: Richard Noll, Aviation Safety
Engineer, Boston Aircraft Certification Office, 12 New England
Executive Park, Burlington, MA 01803, telephone (781) 238-7160, fax
(781) 238-7170.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to submit any written data, views, or arguments
regarding this proposed AD. Send your comments to the address listed
under the caption ADDRESSES. Include the docket number ``FAA-2008-0609,
Directorate Identifier 2008-SW-24-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of the proposed AD. We will
consider all comments received by the closing date and may amend the
proposed AD in light of those comments.
We will post all comments we receive, without change, to https://
www.regulations.gov, including any personal information you provide. We
[[Page 31781]]
will also post a report summarizing each substantive verbal contact
with FAA personnel concerning this proposed rulemaking. Using the
search function of the docket Web site, you can find and read the
comments to any of our dockets, and if provided, the name of the
individual who sent or signed the comment. You may review the DOT's
complete Privacy Act Statement in the Federal Register published on
April 11, 2000 (65 FR 19477).
Examining the Docket
You may examine the docket that contains the proposed AD, any
comments, and other information in person at the Docket Operations
office between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The Docket Operations office (telephone (800) 647-5527) is
located in Room W12-140 on the ground floor of the West Building at the
street address stated in the ADDRESSES section. Comments will be
available in the AD docket shortly after receipt.
Discussion
This document proposes adopting a new AD for Sikorsky Model S-76A,
S-76B, and S-76C helicopters with any of the following part-numbered
aft spar assemblies installed:
------------------------------------------------------------------------
Aft spar assembly
Helicopter model part No.
------------------------------------------------------------------------
S-76A............................................... 76201-05002-114
76201-05002-115
S-76B and S-76C..................................... 76201-05002-047
76201-05002-048
76201-25002-041
76201-25002-044
76201-25002-045
76201-25002-046
------------------------------------------------------------------------
For any aft spar assembly having 1,000 or more hours time-in-
service (TIS), the AD would require, initially and then at intervals
not to exceed 50 hours TIS, inspecting the aft spar assembly for a
crack, a loose or working fastener, or corrosion. If a crack, a loose
or working fastener, or corrosion is found, repairing or replacing any
unairworthy parts and inspecting the forward spar assembly would be
required before further flight. If that inspection reveals a crack, a
loose or working fastener, or corrosion in the forward spar assembly,
then the damage would have to be repaired or the parts would need to be
replaced with airworthy parts before further flight. The AD would also
require a track-and-balance of the tail rotor within 30 days and
thereafter at intervals not to exceed 200 hours TIS. The AD would also
require, on or before December 31, 2010, installing a vertical
stabilizer modification kit, part number (P/N) 76070-20562, 76070-
20563, or 76070-20564, which would be terminating action for the
requirements of the AD.
This proposal is prompted by 26 reports of fatigue cracks in the
aft spar assembly web and outer caps since February 1998. The actions
specified in this proposed AD are intended to detect and correct an
unbalanced or out-of-track tail rotor, which could lead to increased
vibrations, a fatigue crack, loss of a portion of the vertical
stabilizer and subsequent loss of control of the helicopter.
We have reviewed the following service information:
Sikorsky Alert Service Bulletin (ASB) No. 76-55-20A,
Revision A, dated November 11, 2003, that applies to Sikorsky Model S-
76A and Model S-76C helicopters and describes procedures for a one-time
inspection of the vertical stabilizer aft spar assembly for cracks,
loose or working fasteners, and/or corrosion, and if necessary an
inspection of the forward spar assembly.
ASB No. 76-65-58A, Revision A, dated November 11, 2003,
that applies to all Sikorsky Model S-76 serial numbered helicopters up
to and including 760526 and describes procedures for an initial
enhanced tail rotor balance check.
This proposal would differ from those ASBs in that the inspections
described in ASB No. 76-55-20A would be required for the Model S-76B
helicopters as well as for the Model S-76A and Model S-76C helicopters.
Also, the proposed AD would require repetitive inspections of the aft
spar assembly and the forward spar assembly, if necessary, and
repetitive tail rotor track-and-balance inspections, whereas the two
ASBs specify only a one-time tail rotor balance check and an aft spar
assembly inspection and, if necessary, a one-time forward spar assembly
inspection.
This unsafe condition is likely to exist or develop on other
helicopters of the same type designs. Therefore, the proposed AD would
require, for any spar assembly that has 1,000 or more hours TIS, within
30 days and thereafter at intervals not to exceed 50 hours TIS,
inspecting the aft spar assembly, and if you find a crack, a loose or
working fastener, or corrosion, inspecting the forward spar assembly
before further flight and replacing or repairing any unairworthy part
with an airworthy part before further flight.
The AD would also require, within 30 days and thereafter at
intervals not to exceed 200 hours TIS, inspecting the tail rotor track-
and-balance. Accomplishing the tail rotor track-and-balance inspection
would involve both a pilot and mechanic. The pilot's function would be
to operate the helicopter to a ``light on wheels'' state--almost to the
point of takeoff, and the mechanic would accomplish the vibration
measurements. Also, the AD would require, on or before December 31,
2010, installing a vertical stabilizer modification kit, P/N 76070-
20562, 76070-20563, or 76070-20564, which would be terminating action
for the requirements of the AD. The inspections and repairs or
replacements, if necessary, would have to be accomplished in accordance
with specified portions of the ASBs previously described.
We estimate that this proposed AD would affect 216 helicopters of
U.S. registry. We also estimate that the inspections for a crack, a
loose or working fastener, or corrosion would take approximately 7 work
hours per helicopter to accomplish; the tail rotor track-and-balance
inspections and adjustments would take approximately 10 work hours per
helicopter; and installing the vertical stabilizer modification kit
would take approximately 120 hours, at an average labor rate of $80 per
work hour. The vertical stabilizer modification kit would cost
approximately $4,250. Based on these figures, we estimate the total
cost impact of this AD on U.S. operators would be $4,961,520, assuming
that, on each helicopter, 12 spar assembly inspections would be done
($1,451,520), that 3 tail rotor track-and-balance inspections would be
done ($518,400), that no spar assembly would need to be repaired or
replaced, and that the vertical stabilizer modification is done.
Regulatory Findings
We have determined that this proposed AD would not have federalism
implications under Executive Order 13132. Additionally, this proposed
AD would 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 proposed
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.
[[Page 31782]]
We prepared a draft economic evaluation of the estimated costs to
comply with this proposed AD. See the AD docket to examine the draft
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, Safety.
The Proposed Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration proposes to amend
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:
Sikorsky Aircraft Corporation: Docket No. FAA-2008-0609; Directorate
Identifier 2008-SW-24-AD.
Applicability: Model S-76A, S-76B, and S-76C helicopters with
any of the following part-numbered vertical stabilizer aft spars
assemblies having 1,000 or more hours time-in-service (TIS)
installed, certificated in any category.
------------------------------------------------------------------------
Vertical
stabilizer aft
Helicopter model spar assembly part
No.
------------------------------------------------------------------------
S-76A............................................... 76201-05002-114
76201-05002-115
S-76B and S-76C..................................... 76201-05002-047
76201-05002-048
76201-25002-041
76201-25002-044
76201-25002-045
76201-25002-046
------------------------------------------------------------------------
Compliance: Required as indicated.
To detect and correct an unbalanced or out-of-track tail rotor,
which could lead to increased vibrations a fatigue crack, loss of a
portion of the vertical stabilizer, and subsequent loss of control
of the helicopter, accomplish the following:
(a) Within 30 days, unless accomplished previously, and
thereafter at intervals not to exceed 50 hours TIS, inspect the
vertical stabilizer aft spar assembly (aft spar assembly) for a
crack, a loose or working fastener, or corrosion in accordance with
the Accomplishment Instructions, paragraph 3.A., in Sikorsky Alert
Service Bulletin (ASB) No. 76-55-20A, Revision A, dated November 11,
2003 (No. 76-55-20A). For purposes of this AD, ASB No 76-55-20A
pertains to Model S-76B helicopters as well as Model S-76A and S-76C
helicopters.
(1) If a crack, a loose or working fastener, or corrosion is
found in the aft spar assembly, before further flight:
(i) Repair or replace any unairworthy parts and
(ii) Inspect the vertical stabilizer forward spar assembly
(forward spar assembly) for a crack, a loose or working fastener, or
corrosion in accordance with the Accomplishment Instructions,
paragraph 3.B., in ASB No. 76-55-20A. Contacting the manufacturer is
not required by this AD.
(2) If a crack, a loose or working fastener, or corrosion is
found in the forward spar assembly, repair in accordance with the
applicable maintenance manual or replace with airworthy parts before
further flight.
(b) Within 30 days, unless accomplished previously, and
thereafter at intervals not to exceed 200 hours TIS, track-and-
balance the tail rotor in accordance with the Accomplishment
Instructions, paragraph 3.A., in ASB No. 76-65-58A, dated November
11, 2003.
Note 1: Although the ASB specifies only an initial inspection of
the aft spar assembly and a track-and-balance of the tail rotor,
this AD requires inspecting the aft spar assembly and track-and-
balancing the tail rotor repetitively.
Note 2: The track-and-balancing of the tail rotor that is
required by paragraph (b) of this AD involves both a pilot and
mechanic. The pilot's function is to operate the helicopter to a
``light on wheels'' state--almost to the point of takeoff. The
mechanic is needed to accomplish the vibration measurements.
(c) On or before December 31, 2010, install a vertical
stabilizer modification kit, part number 76070-20562, 76070-20563,
or 76070-20564. Installing the vertical stabilizer modification kit
is terminating action for the requirements of this AD.
(d) 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 Manager, Boston Aircraft Certification Office, Engine
and Propeller Directorate, ATTN: Richard Noll, Aviation Safety
Engineer, FAA, 12 New England Executive Park, Burlington, MA 01803,
telephone (781) 238-7160, fax (781) 238-7170, for information about
previously approved alternative methods of compliance.
Issued in Fort Worth, Texas, on May 22, 2008.
David A. Downey,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. E8-12414 Filed 6-3-08; 8:45 am]
BILLING CODE 4910-13-P
