Airworthiness Directives; Boeing Model 737 Airplanes, 22840-22845 [E8-9193]
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22840
Federal Register / Vol. 73, No. 82 / Monday, April 28, 2008 / Proposed Rules
NCUA proposes to revise § 740.5(b) to
permit insured credit unions to use, in
addition to the basic form of the official
advertising statement, the shortened
form or the official sign in their
advertisements. In other words, the
proposed rule will permit insured credit
unions, in addition to using the official
advertising statement in its
advertisements, to use the shortened
statement alone or the official sign alone
in advertisements. The flexibility this
would provide is currently available
under the Federal Deposit Insurance
Corporation’s rule regarding disclosure
of insured status in advertisements. 12
CFR 328.3.
Additionally, the proposed
amendment clarifies the font of the text
in the official sign may be altered as
described in § 740.4(b)(2) when it is
used as the official advertising
statement. 12 CFR 740.4(b)(2).
Regulatory Procedures
Regulatory Flexibility Act
The Regulatory Flexibility Act
requires NCUA to prepare an analysis to
describe any significant economic
impact any proposed regulation may
have on a substantial number of small
credit unions (those under $10 million
in assets). The proposed amendment
merely expands the options credit
unions have to comply with the
requirement to notify members and the
public of their insured status in
advertisements. Accordingly, the NCUA
has determined and certifies that the
proposed rule, if adopted, will not have
a significant economic impact on a
substantial number of small credit
unions within the meaning of the
Regulatory Flexibility Act, 5 U.S.C. 601–
612.
Paperwork Reduction Act
The proposed rule does not contain a
‘‘collection of information’’ within the
meaning of section 3502(3) of the
Paperwork Reduction Act of 1995 (44
U.S.C. 3502(3)) and would not increase
paperwork requirements under the
Paperwork Reduction Act of 1995 or
regulations of the Office of Management
and Budget.
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Executive Order 13132
Executive Order 13132 encourages
independent regulatory agencies to
consider the impact of their actions on
state and local interests. In adherence to
fundamental federalism principles,
NCUA, an independent regulatory
agency as defined in 44 U.S.C. 3502(5),
voluntarily complies with the executive
order. The proposed rule would not
have substantial direct effect on the
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states, on the connection between the
national government and the states, or
on the distribution of power and
responsibilities among the various
levels of government. NCUA has
determined that this proposed rule does
not constitute a policy that has
federalism implications for purposes of
the executive order.
statement, an insured credit union may
alter the font size to ensure its legibility
as provided in paragraph (b)(2) of
§ 740.4.
*
*
*
*
*
The Treasury and General Government
Appropriations Act, 1999—Assessment
of Federal Regulations and Policies on
Families
NCUA has determined that this
proposed rule would not affect family
well-being within the meaning of
section 654 of the Treasury and General
Government Appropriations Act, 1999,
Pub. L. 105–277, 112 Stat. 2681 (1998).
DEPARTMENT OF TRANSPORTATION
Agency Regulatory Goal
NCUA’s goal is to promulgate clear
and understandable regulations that
impose minimal regulatory burden. We
request your comments on whether the
proposed amendment is understandable
and minimally intrusive if implemented
as proposed.
List of Subjects in 12 CFR Part 740
Advertisements, Credit unions, Signs
and symbols.
By the National Credit Union
Administration Board on April 17, 2008.
Mary F. Rupp,
Secretary of the Board.
For the reasons set forth above, it is
proposed that 12 CFR part 740 be
amended as follows:
PART 740—ACCURACY OF
ADVERTISING AND NOTICE OF
INSURED STATUS
1. The authority citation for part 740
is revised to read as follows:
Authority: 12 U.S.C. 1766, 1781, 1785, and
1789.
2. Section 740.5 is amended by
revising paragraph (b) to read as follows:
§ 740.5 Requirements for the official
advertising statement.
*
*
*
*
*
(b) The official advertising statement
is in substance as follows: ‘‘This credit
union is federally insured by the
National Credit Union Administration.’’
Insured credit unions, at their option,
may use the short title ‘‘Federally
insured by NCUA’’ or a reproduction of
the official sign, as described in
§ 740.4(b), as the official advertising
statement. The official advertising
statement must be in a size and print
that is clearly legible. If the official sign
is used as the official advertising
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[FR Doc. E8–8967 Filed 4–25–08; 8:45 am]
BILLING CODE 7535–01–P
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2008–0415; Directorate
Identifier 2007–NM–256–AD]
RIN 2120–AA64
Airworthiness Directives; Boeing
Model 737 Airplanes
Federal Aviation
Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking
(NPRM).
AGENCY:
SUMMARY: We propose to adopt a new
airworthiness directive (AD) for certain
Boeing Model 737 airplanes. This
proposed AD would require repetitive
inspections, lubrications, and repetitive
repairs/overhauls of the ball nut and
ballscrew and attachment (Gimbal)
fittings for the trim actuator of the
horizontal stabilizer; various
installation(s); and corrective actions if
necessary; as applicable. This proposed
AD results from a report of extensive
corrosion of a ballscrew used in the
drive mechanism of the horizontal
stabilizer trim actuator (HSTA). We are
proposing this AD to prevent an
undetected failure of the primary load
path for the ballscrew in the drive
mechanism of the HSTA and
subsequent wear and failure of the
secondary load path, which could lead
to loss of control of the horizontal
stabilizer and consequent loss of control
of the airplane.
DATES: We must receive comments on
this proposed AD by June 12, 2008.
ADDRESSES: You may send comments by
any of the following methods:
• 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.,
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Federal Register / Vol. 73, No. 82 / Monday, April 28, 2008 / Proposed Rules
Washington, DC 20590, between 9 a.m.
and 5 p.m., Monday through Friday,
except Federal holidays.
For service information identified in
this AD, contact Boeing Commercial
Airplanes, P.O. Box 3707, Seattle,
Washington 98124–2207.
Examining the AD Docket
You may examine the AD docket on
the Internet at https://
www.regulations.gov; or in person at the
Docket Management Facility between 9
a.m. and 5 p.m., Monday through
Friday, except Federal holidays. The AD
docket contains this proposed AD, the
regulatory evaluation, any comments
received, and other information. The
street address for the Docket Office
(telephone 800–647–5527) is in the
ADDRESSES section. Comments will be
available in the AD docket shortly after
receipt.
FOR FURTHER INFORMATION CONTACT:
Kelly McGuckin, Aerospace Engineer,
Systems and Equipment Branch, ANM–
130S, FAA, Seattle Aircraft Certification
Office, 1601 Lind Avenue, SW., Renton,
Washington 98057–3356; telephone
(425) 917–6490; fax (425) 917–6590.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written
relevant data, views, or arguments about
this proposed AD. Send your comments
to an address listed under the
ADDRESSES section. Include ‘‘Docket No.
FAA–2008–0415; Directorate Identifier
2007–NM–256–AD’’ at the beginning of
your comments. We specifically invite
comments on the overall regulatory,
economic, environmental, and energy
aspects of this proposed AD. We will
consider all comments received by the
closing date and may amend this
proposed AD because of those
comments.
We will post all comments we
receive, without change, to https://
www.regulations.gov, including any
personal information you provide. We
will also post a report summarizing each
substantive verbal contact we receive
about this proposed AD.
Discussion
On January 31, 2000, there was an
accident involving a McDonnell Douglas
Model DC–9–83 (MD–83) airplane. The
National Transportation Safety Board
(NTSB) determined that the probable
cause of the accident was a loss of
airplane pitch control resulting from the
in-flight failure of the acme nut threads
of the jackscrew assembly of the
horizontal stabilizer trim system. The
NTSB concluded that the thread failure
was caused by excessive wear, resulting
from insufficient lubrication of the
jackscrew assembly. The drive
mechanism of the horizontal stabilizer
on Model MD–83 airplanes has a
jackscrew assembly with an acme screw.
The drive mechanism of the horizontal
stabilizer on Boeing Model 737
airplanes has a horizontal stabilizer trim
actuator (HSTA) with a ballscrew. Acme
22841
screws and ballscrews have some
differences in design, but perform
similar functions and have the same
airplane-level effect following failure.
In response to this accident, Boeing
initiated a design review and safety
analysis of the primary and secondary
load paths of the ballscrew assembly
used on the HSTA of their airplanes.
During this review, one operator of a
Model 757 airplane reported extensive
corrosion of a ballscrew assembly of the
HSTA. Investigation revealed extensive
corrosion of the primary load path ball
bearings in the ballscrew assembly. This
condition, if not corrected, could result
in an undetected failure of the primary
load path for the ballscrew in the drive
mechanism of the HSTA and
subsequent wear and failure of the
secondary load path, which could lead
to loss of control of the horizontal
stabilizer and consequent loss of control
of the airplane.
The ballscrew assembly on Model 757
airplanes is similar to those on the
affected Model 737 airplanes. Therefore,
all of these models may be subject to the
same unsafe condition.
Other Relevant Rulemaking
We are considering additional
rulemaking to address the identified
unsafe condition on Model 757
airplanes.
Relevant Service Information
We have reviewed the following
Boeing Service Bulletins:
TABLE—PRIMARY SERVICE BULLETINS
Describes the following procedures for the
trim actuator of the horizontal stabilizer (depending on the airplane configuration)—
Boeing Alert Service Bulletin—
737–27A1277, Revision 1, dated July 25, 2007
(for Model 737–600, –700, –700C, –800,
–900, and –900ER series airplanes).
And recommends that those actions be
done—
Repetitive detailed and general visual inspections to detect discrepancies (e.g., metal
particles or corrosion in grease, damage,
cracks, corrosion, worn areas, grease leakage, and loose ball bearings) of the ball nut
and ballscrew.
Repetitive lubrications of the ball nut and
ballscrew.
Within 6,400 flight hours or 18 months from
the last detailed inspection, whichever occurs first, and thereafter at intervals not to
exceed 6,400 flight hours or 2 years, whichever occurs first.
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Repetitive repair/overhaul ................................
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Within 1,600 flight hours or 1 year from the
last lubrication, whichever occurs first, and
thereafter at intervals not to exceed 1,600
flight hours or 1 year, whichever occurs
first.
Before the accumulation of 25,000 flight hours
since the date of issuance of the original
standard airworthiness certificate or the
date of issuance of the original export certificate of airworthiness, or within 25,000
flight hours since the last overhaul of the
trim actuator of the horizontal stabilizer,
whichever occurs first, and thereafter at intervals not to exceed 25,000 flight hours.
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Federal Register / Vol. 73, No. 82 / Monday, April 28, 2008 / Proposed Rules
TABLE—PRIMARY SERVICE BULLETINS—Continued
Describes the following procedures for the
trim actuator of the horizontal stabilizer (depending on the airplane configuration)—
737–27A1278, dated May 24, 2007 (for Model
737–100, –200, –200C, –300, –400, and
–500 series airplanes).
And recommends that those actions be
done—
Installation of tube retainers on the ball nut ....
Boeing Alert Service Bulletin—
Before the accumulation of 25,000 flight hours
since the date of issuance of the original
standard airworthiness certificate or the
date of issuance of the original export certificate of airworthiness, or within 25,000
flight hours since the latest overhaul of the
trim actuator of the horizontal stabilizer,
whichever occurs later.
Before further flight.
Applicable corrective actions. The corrective
actions include repairing/replacing discrepant parts.
Repetitive detailed and general visual inspections to detect discrepancies (e.g., metal
particles or corrosion in grease, damage,
cracks, corrosion, worn areas, grease leakage, and loose ball bearings) of the ball nut
and ballscrew and attachment (Gimbal) fittings.
Repetitive lubrications of the ball nut and
ballscrew and attachment (Gimbal) fittings.
Repetitive repair/overhaul ................................
Installation of tube retainers on the ball nut ....
Installation of a grease fitting ...........................
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Installation of new ball deflectors and guide
clamps for the ball return.
Installation of new return tube clamps .............
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Within 2,000 or 4,000 flight hours or 12 or 18
months from the last detailed inspection,
whichever occurs first, and thereafter at intervals not to exceed 2,000 or 4,000 flight
hours or 1 or 2 years, whichever occurs
first (depending on the airplane configuration).
Within 500 or 2,000 flight hours or 2 months
or 1 year from the last lubrication, whichever occurs first, and thereafter at intervals
not to exceed 500 or 2,000 flight hours or 2
months or 1 year, whichever occurs first
(depending on the airplane configuration).
Before the accumulation of 20,000 flight hours
or 24,000 flight hours since the date of
issuance of the original standard airworthiness certificate or the date of issuance of
the original export certificate of airworthiness, or within 20,000 flight hours or 24,000
flight hours since the last overhaul of the
trim actuator of the horizontal stabilizer,
whichever occurs first (depending on the
airplane configuration); and thereafter at intervals not to exceed 20,000 or 25,000
flight cycles (depending on the airplane
configuration).
Before the accumulation of 24,000 flight hours
since the date of issuance of the original
standard airworthiness certificate or the
date of issuance of the original export certificate of airworthiness, or within 24,000
flight hours since the last overhaul of the
trim actuator of the horizontal stabilizer,
whichever occurs first.
Before the accumulation of 20,000 flight hours
since the date of issuance of the original
standard airworthiness certificate or the
date of issuance of the original export certificate of airworthiness, or within 20,000
flight hours since the last overhaul of the
trim actuator of the horizontal stabilizer,
whichever occurs first.
Before the accumulation of 24,000 flight hours
since the date of issuance of the original
standard airworthiness certificate or the
date of issuance of the original export certificate of airworthiness, or within 24,000
flight hours since the last overhaul of the
trim actuator of the horizontal stabilizer,
whichever occurs first.
Before the accumulation of 20,000 flight hours
since the date of issuance of the original
standard airworthiness certificate or the
date of issuance of the original export certificate of airworthiness, or within 20,000
flight hours since the last overhaul of the
trim actuator of the horizontal stabilizer,
whichever occurs first.
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Federal Register / Vol. 73, No. 82 / Monday, April 28, 2008 / Proposed Rules
TABLE—PRIMARY SERVICE BULLETINS—Continued
Describes the following procedures for the
trim actuator of the horizontal stabilizer (depending on the airplane configuration)—
And recommends that those actions be
done—
Applicable corrective actions. The corrective
actions include repairing/replacing discrepant parts.
Boeing Alert Service Bulletin—
Before further flight.
TABLE.—SECONDARY SERVICE BULLETINS
Boeing Alert Service Bulletin—
Refers to—
737–27A1277, Revision 1, dated July 25, 2007 (for Model 737–600,
–700, –700C, –800, –900, and –900ER series airplanes).
UMBRA CUSCINETTI Service Bulletin 07322–27–01, dated December
21, 2004, as an additional source of service information for installing
tube retainers on the ball nut.
UMBRA CUSCINETTI Service Bulletin 07322–27–01, dated December
21, 2004, as an additional source of service information for installing
tube retainers on the ball nut.
Boeing 737 Service Bulletin 27–1046, Revision 1, dated April 5, 1974,
as an additional source of service information for installing a grease
fitting.
Linear Motion Service Bulletin 7901708, Revision A, dated July 26,
2005, as an additional source of service information for installing
new ball deflectors and guide clamps for the ball return.
SKYTRONICS Service Bulletin 93004, dated September 1, 2005, as an
additional source of service information for installing new return tube
clamps.
737–27A1278, dated May 24, 2007 (for Model 737–100, –200, –200C,
–300, –400, and –500 series airplanes).
FAA’s Determination and Requirements
of This Proposed AD
We are proposing this AD because we
evaluated all relevant information and
determined the unsafe condition
described previously is likely to exist or
develop in other products of the(se)
same type design(s). This proposed AD
would require accomplishing the
actions specified in the primary service
bulletins described previously.
Clarification of Applicability of This
AD
Model 737–900ER series airplanes
where appropriate.
Boeing has informed us that Model
737–900ER series airplanes were not
specifically identified by model name in
the Effectivity section of Boeing Alert
Service Bulletin 737–27A1277.
However, those airplanes are identified
by variable numbers in the Effectivity
section. Therefore, this AD refers to
Costs of Compliance
We estimate that this proposed AD
would affect 1,602 Model 737 airplanes
of U.S. registry. The following table
provides the estimated costs for U.S.
operators to comply with this proposed
AD.
ESTIMATED COSTS
Number
of U.S.registered
airplanes
Action 1
Work hours 1
Average
labor rate
per hour
Detailed inspections .............
2 or 4 ............
$80
None
$160 or $320, per inspection
cycle.
1,602
Lubrications ..........................
1 or 3 ............
80
None
$80 or $240, per lubrication
cycle.
1,602
Repairs/overhauls ................
40 ..................
80
None
$3,200 per repair/overhaul ..
1,602
Installations ..........................
Between 1
and 3.
80
$2,200
Between $2,280 and $2,440
1,320
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1 Depending
Cost per product 1
Fleet cost 1
Between $256,320, and
$512,640 per inspection
cycle.
Between $128,160, and
$384,480 per lubrication
cycle.
$5,126,400 per repair/overhaul cycle.
Between $3,009,600 and
$3,220,800.
on airplane configuration.
The number of work hours, as
indicated above, is presented as if the
accomplishment of the actions in this
proposed AD is to be conducted as new
‘‘stand alone’’ actions. However, in
actual practice, the lubrications,
detailed inspections, and overhauls are
currently being done as part of normal
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airplane maintenance. The repair can be
done coincidentally or in combination
with the normally scheduled HSTA and
ballscrew overhaul. Therefore, the
actual number of necessary additional
work hours will be minimal in many
instances. Additionally, any costs
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associated with special airplane
scheduling will be minimal.
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
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Federal Register / Vol. 73, No. 82 / Monday, April 28, 2008 / Proposed Rules
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.
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 this 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.
You can find our regulatory
evaluation and the estimated costs of
compliance in the AD Docket.
the FAA proposes to amend 14 CFR part
39 as follows:
Regulatory Findings
We determined that this proposed AD
would not have federalism implications
under Executive Order 13132. This
proposed AD would not have a
substantial direct effect on the States, on
the relationship between the national
List of Subjects in 14 CFR Part 39
Affected ADs
Air transportation, Aircraft, Aviation
safety, Safety.
The Proposed Amendment
Accordingly, under the authority
delegated to me by the Administrator,
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. The FAA amends § 39.13 by adding
the following new AD:
Boeing: Docket No. FAA–2008–0415;
Directorate Identifier 2007–NM–256–AD.
Comments Due Date
(a) We must receive comments by June 12,
2008.
(b) None.
Applicability
(c) This AD applies to Boeing airplanes
identified in Table 1 of this AD, certificated
in any category.
TABLE 1.—APPLICABILITY
Boeing model—
As identified in Boeing Alert Service Bulletin—
(1) 737–100, –200, –200C, –300, –400, and –500 series airplanes .......
(2) 737–600, –700, –700C, –800, –900, and –900ER series airplanes ..
Unsafe Condition
(d) This AD results from a report of
extensive corrosion of a ballscrew in the
drive mechanism of the horizontal stabilizer
trim actuator (HSTA). We are issuing this AD
to prevent an undetected failure of the
primary load path for the ballscrew in the
drive mechanism of the HSTA and
737–27A1278, dated May 24, 2007.
737–27A1277, Revision 1, dated July 25, 2007.
subsequent wear and failure of the secondary
load path, which could lead to loss of control
of the horizontal stabilizer and consequent
loss of control of the airplane.
Compliance
(e) Comply with this AD within the
compliance times specified, unless already
done.
Service Bulletins
(f) The term ‘‘service bulletin,’’ as used in
this AD, means the applicable service
bulletins specified in Table 2 of this AD.
TABLE 2.—SERVICE BULLETINS
Boeing Alert Service Bulletin—
For model—
(1) 737–27A1278, dated May 24, 2007 ...................................................
(2) 737–27A1277, Revision 1, dated July 25, 2007 ................................
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Note 1: The service bulletins refer to
UMBRA CUSCINETTI Service Bulletin
07322–27–01, dated December 21, 2004;
Linear Motion Service Bulletin 7901708,
Revision A, dated July 26, 2005; Boeing 737
Service Bulletin 27–1046, Revision 1, dated
April 5, 1974; and/or SKYTRONICS Service
Bulletin 93004, dated September 1, 2005, as
applicable, as additional sources of service
information for accomplishing the specified
actions.
Inspections, Lubrications, Repairs/
Overhauls, and Applicable Corrective
Actions
(g) At the applicable compliance time and
repeat intervals listed in Tables 1 and 2 of
paragraph 1.E., ‘‘Compliance,’’ of the service
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737–100, –200, –200C, –300, –400, and –500 series airplanes.
737–600, –700, –700C, –800, –900, and –900ER series airplanes.
bulletin, do the inspections, lubrications,
repairs/overhauls, installation(s), and
applicable corrective actions by
accomplishing all the applicable actions
specified in the Accomplishment
Instructions of the service bulletin; except as
provided by paragraphs (g)(1) through (g)(3)
of this AD.
(1) Where paragraph 1.E., ‘‘Compliance,’’ of
the service bulletin specifies an initial
compliance time for accomplishing the initial
inspection, lubrication, or repair/overhaul,
this AD requires doing the applicable initial
action(s) at the later of the times specified in
paragraphs (g)(1)(i) and (g)(1)(ii) of this AD.
(i) At the applicable compliance time
specified in paragraph 1.E., ‘‘Compliance,’’ of
the service bulletin.
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(ii) Within the applicable compliance time
specified in paragraph (g)(1)(ii)(A),
(g)(1)(ii)(B), or (g)(1)(ii)(C) of this AD.
(A) For the initial detailed inspection and
lubrication: Within 6 months after the
effective date of this AD.
(B) For the initial repair/overhaul: Within
12 months after the effective date of this AD.
(C) For the installation(s): Within 12
months after the effective date of this AD.
(2) Where Table 2 of paragraph 1.E.,
‘‘Compliance,’’ of Boeing Alert Service
Bulletin 737–27A1277, Revision 1, dated July
25, 2007, specifies a compliance time of
‘‘* * * within 25,000 Flight Hours since the
latest horizontal stabilizer trim actuator
(HSTA) Overhaul from the date of Revision
1 of this Service Bulletin * * *,’’ this AD
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Federal Register / Vol. 73, No. 82 / Monday, April 28, 2008 / Proposed Rules
requires compliance ‘‘* * * within 25,000
flight hours since the last overhaul of the
trim actuator of the horizontal stabilizer.’’
(3) Where Work Package 4, paragraphs 1.a.,
2.a., and 3.a., of the Accomplishment
Instructions of Boeing Alert Service Bulletin
737–27A1278, dated May 24, 2007, specifies
to identify the HSTA name plate ‘‘* * * AS
GIVEN IN SB 737–27A1278, WORK
PACKAGE 3,’’ this AD requires that
identification ‘‘ * * * AS GIVEN IN SB 737–
27A1278, WORK PACKAGE 4.’’
(4) Where Note (b) of Figures 7 through 9
of Boeing Alert Service Bulletin 737–
27A1278, dated May 24, 2007, specifies to do
a ‘‘* * * Backlash Inspection as given in
AMM 27–41–81/606,’’ this AD requires an
‘‘* * * End Play Test as given in OHM 27–
45–11 page 701.’’
(h) Actions done before the effective date
of this AD in accordance with Boeing Alert
Service Bulletin 737–27A1277, dated July 21,
2005, are acceptable for compliance with the
corresponding requirements of this AD.
Alternative Methods of Compliance
(AMOCs)
(i)(1) The Manager, Seattle Aircraft
Certification Office, FAA, ATTN: Kelly
McGuckin, Aerospace Engineer, Systems and
Equipment Branch, ANM–130S, FAA, Seattle
Aircraft Certification Office, 1601 Lind
Avenue, SW., Renton, Washington 98057–
3356; telephone (425) 917–6490; fax (425)
917–6590; has the authority to approve
AMOCs for this AD, if requested using the
procedures found in 14 CFR 39.19.
(2) To request a different method of
compliance or a different compliance time
for this AD, follow the procedures in 14 CFR
39.19. Before using any approved AMOC on
any airplane to which the AMOC applies,
notify your appropriate principal inspector
(PI) in the FAA Flight Standards District
Office (FSDO), or lacking a PI, your local
FSDO.
Issued in Renton, Washington, on April 17,
2008.
Ali Bahrami,
Manager, Transport Airplane Directorate,
Aircraft Certification Service.
[FR Doc. E8–9193 Filed 4–25–08; 8:45 am]
BILLING CODE 4910–13–P
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA–2008–0414; Directorate
Identifier 2007–NM–095–AD]
rwilkins on PROD1PC63 with PROPOSALS
RIN 2120–AA64
Airworthiness Directives; Boeing
Model 747–100, 747–100B, 747–100B
SUD, 747–200B, 747–200C, 747–200F,
747–300, 747–400, 747–400D, 747–
400F, and 747SR Series Airplanes
Federal Aviation
Administration (FAA), Department of
Transportation (DOT).
AGENCY:
VerDate Aug<31>2005
17:54 Apr 25, 2008
Jkt 214001
Notice of proposed rulemaking
(NPRM).
ACTION:
SUMMARY: The FAA proposes to
supersede an existing airworthiness
directive (AD) that applies to certain
Boeing Model 747 series airplanes. The
existing AD currently requires repetitive
inspections for cracking and corrosion
of all exposed surfaces of the carriage
spindles (including the inner bore and
aft links) of the trailing edge flaps, and
additional inspection and corrective
action if necessary. The existing AD also
requires repetitive overhaul of the
carriage spindle and aft link, which
terminates the repetitive inspections.
This proposed AD would add a
repetitive inspection to detect broken
parts, and revise the overhaul threshold
and repetitive intervals. This proposed
AD results from analysis that showed
additional inspections should be done
to prevent the loss of a flap, and that the
flight-hour-based interval should be
revised to a flight-cycle-based interval,
because the greatest loads on the
spindles happen during takeoff and
landing. We are proposing this AD to
detect and correct failed carriage
spindles or aft links for the inboard or
outboard trailing edge flaps. Such
failure could cause the flap to depart the
airplane, reducing the flightcrew’s
ability to maintain the safe flight and
landing of the airplane.
DATES: We must receive comments on
this proposed AD by June 12, 2008.
ADDRESSES: You may send comments by
any of the following methods:
• 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.
For service information identified in
this AD, contact Boeing Commercial
Airplanes, P.O. Box 3707, Seattle,
Washington 98124–2207.
Examining the AD Docket
You may examine the AD docket on
the Internet at https://
www.regulations.gov; or in person at the
Docket Management Facility between 9
a.m. and 5 p.m., Monday through
Friday, except Federal holidays. The AD
docket contains this proposed AD, the
PO 00000
Frm 00010
Fmt 4702
Sfmt 4702
22845
regulatory evaluation, any comments
received, and other information. The
street address for the Docket Office
(telephone 800–647–5527) is in the
ADDRESSES section. Comments will be
available in the AD docket shortly after
receipt.
FOR FURTHER INFORMATION CONTACT: Gary
Oltman, Aerospace Engineer, Airframe
Branch, ANM–120S, FAA, Seattle
Aircraft Certification Office, 1601 Lind
Avenue, SW., Renton, Washington
98057–3356; telephone (425) 917–6443;
fax (425) 917–6590.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written
relevant data, views, or arguments about
this proposed AD. Send your comments
to an address listed under the
ADDRESSES section. Include ‘‘Docket No.
FAA–2008–0414; Directorate Identifier
2007–NM–095–AD’’ at the beginning of
your comments. We specifically invite
comments on the overall regulatory,
economic, environmental, and energy
aspects of this proposed AD. We will
consider all comments received by the
closing date and may amend this
proposed AD because of those
comments.
We will post all comments we
receive, without change, to https://
www.regulations.gov, including any
personal information you provide. We
will also post a report summarizing each
substantive verbal contact we receive
about this proposed AD.
Discussion
On August 6, 1990, we issued AD 90–
17–19, amendment 39–6705 (55 FR
33280, August 15, 1990), for all Boeing
Model 747 series airplanes, except the
Model 747SP. That AD requires
repetitive inspections for cracking and
corrosion of all exposed surfaces of the
carriage spindles (including the inner
bore and aft links) of the trailing edge
flaps, and additional inspection and
corrective action if necessary. The
existing AD also requires repetitive
overhaul of the carriage spindle and aft
link, which terminates the repetitive
inspections. That AD resulted from a
report of failure of two aft links in the
spindles on one flap, causing control
problems during approach and landing.
We issued that AD to prevent failure of
the trailing edge flaps’ carriage spindles,
which could result in reduced
controllability of the airplane.
Actions Since Existing AD Was Issued
Since we issued AD 90–17–19, the
manufacturer conducted a dynamic
aerodynamic analysis, which showed
that the airplane might not have
E:\FR\FM\28APP1.SGM
28APP1
]]>Agencies
[Federal Register Volume 73, Number 82 (Monday, April 28, 2008)]
[Proposed Rules]
[Pages 22840-22845]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E8-9193]
=======================================================================
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2008-0415; Directorate Identifier 2007-NM-256-AD]
RIN 2120-AA64
Airworthiness Directives; Boeing Model 737 Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
-----------------------------------------------------------------------
SUMMARY: We propose to adopt a new airworthiness directive (AD) for
certain Boeing Model 737 airplanes. This proposed AD would require
repetitive inspections, lubrications, and repetitive repairs/overhauls
of the ball nut and ballscrew and attachment (Gimbal) fittings for the
trim actuator of the horizontal stabilizer; various installation(s);
and corrective actions if necessary; as applicable. This proposed AD
results from a report of extensive corrosion of a ballscrew used in the
drive mechanism of the horizontal stabilizer trim actuator (HSTA). We
are proposing this AD to prevent an undetected failure of the primary
load path for the ballscrew in the drive mechanism of the HSTA and
subsequent wear and failure of the secondary load path, which could
lead to loss of control of the horizontal stabilizer and consequent
loss of control of the airplane.
DATES: We must receive comments on this proposed AD by June 12, 2008.
ADDRESSES: You may send comments by any of the following methods:
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.,
[[Page 22841]]
Washington, DC 20590, between 9 a.m. and 5 p.m., Monday through Friday,
except Federal holidays.
For service information identified in this AD, contact Boeing
Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-2207.
Examining the AD Docket
You may examine the AD docket on the Internet at https://
www.regulations.gov; or in person at the Docket Management Facility
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains this proposed AD, the regulatory
evaluation, any comments received, and other information. The street
address for the Docket Office (telephone 800-647-5527) is in the
ADDRESSES section. Comments will be available in the AD docket shortly
after receipt.
FOR FURTHER INFORMATION CONTACT: Kelly McGuckin, Aerospace Engineer,
Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft
Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-
3356; telephone (425) 917-6490; fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written relevant data, views, or
arguments about this proposed AD. Send your comments to an address
listed under the ADDRESSES section. Include ``Docket No. FAA-2008-0415;
Directorate Identifier 2007-NM-256-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of this proposed AD. We
will consider all comments received by the closing date and may amend
this proposed AD because of those comments.
We will post all comments we receive, without change, to https://
www.regulations.gov, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact we
receive about this proposed AD.
Discussion
On January 31, 2000, there was an accident involving a McDonnell
Douglas Model DC-9-83 (MD-83) airplane. The National Transportation
Safety Board (NTSB) determined that the probable cause of the accident
was a loss of airplane pitch control resulting from the in-flight
failure of the acme nut threads of the jackscrew assembly of the
horizontal stabilizer trim system. The NTSB concluded that the thread
failure was caused by excessive wear, resulting from insufficient
lubrication of the jackscrew assembly. The drive mechanism of the
horizontal stabilizer on Model MD-83 airplanes has a jackscrew assembly
with an acme screw. The drive mechanism of the horizontal stabilizer on
Boeing Model 737 airplanes has a horizontal stabilizer trim actuator
(HSTA) with a ballscrew. Acme screws and ballscrews have some
differences in design, but perform similar functions and have the same
airplane-level effect following failure.
In response to this accident, Boeing initiated a design review and
safety analysis of the primary and secondary load paths of the
ballscrew assembly used on the HSTA of their airplanes. During this
review, one operator of a Model 757 airplane reported extensive
corrosion of a ballscrew assembly of the HSTA. Investigation revealed
extensive corrosion of the primary load path ball bearings in the
ballscrew assembly. This condition, if not corrected, could result in
an undetected failure of the primary load path for the ballscrew in the
drive mechanism of the HSTA and subsequent wear and failure of the
secondary load path, which could lead to loss of control of the
horizontal stabilizer and consequent loss of control of the airplane.
The ballscrew assembly on Model 757 airplanes is similar to those
on the affected Model 737 airplanes. Therefore, all of these models may
be subject to the same unsafe condition.
Other Relevant Rulemaking
We are considering additional rulemaking to address the identified
unsafe condition on Model 757 airplanes.
Relevant Service Information
We have reviewed the following Boeing Service Bulletins:
Table--Primary Service Bulletins
------------------------------------------------------------------------
Describes the
following procedures
for the trim
actuator of the And recommends that
Boeing Alert Service horizontal those actions be
Bulletin-- stabilizer done--
(depending on the
airplane
configuration)--
------------------------------------------------------------------------
737-27A1277, Revision 1, Repetitive detailed Within 6,400 flight
dated July 25, 2007 (for and general visual hours or 18 months
Model 737-600, -700, -700C, inspections to from the last
-800, -900, and -900ER detect detailed
series airplanes). discrepancies inspection,
(e.g., metal whichever occurs
particles or first, and
corrosion in thereafter at
grease, damage, intervals not to
cracks, corrosion, exceed 6,400 flight
worn areas, grease hours or 2 years,
leakage, and loose whichever occurs
ball bearings) of first.
the ball nut and
ballscrew.
Repetitive Within 1,600 flight
lubrications of the hours or 1 year
ball nut and from the last
ballscrew. lubrication,
whichever occurs
first, and
thereafter at
intervals not to
exceed 1,600 flight
hours or 1 year,
whichever occurs
first.
Repetitive repair/ Before the
overhaul. accumulation of
25,000 flight hours
since the date of
issuance of the
original standard
airworthiness
certificate or the
date of issuance of
the original export
certificate of
airworthiness, or
within 25,000
flight hours since
the last overhaul
of the trim
actuator of the
horizontal
stabilizer,
whichever occurs
first, and
thereafter at
intervals not to
exceed 25,000
flight hours.
[[Page 22842]]
Installation of tube Before the
retainers on the accumulation of
ball nut. 25,000 flight hours
since the date of
issuance of the
original standard
airworthiness
certificate or the
date of issuance of
the original export
certificate of
airworthiness, or
within 25,000
flight hours since
the latest overhaul
of the trim
actuator of the
horizontal
stabilizer,
whichever occurs
later.
Applicable Before further
corrective actions. flight.
The corrective
actions include
repairing/replacing
discrepant parts.
737-27A1278, dated May 24, Repetitive detailed Within 2,000 or
2007 (for Model 737-100, - and general visual 4,000 flight hours
200, -200C, -300, -400, and inspections to or 12 or 18 months
-500 series airplanes). detect from the last
discrepancies detailed
(e.g., metal inspection,
particles or whichever occurs
corrosion in first, and
grease, damage, thereafter at
cracks, corrosion, intervals not to
worn areas, grease exceed 2,000 or
leakage, and loose 4,000 flight hours
ball bearings) of or 1 or 2 years,
the ball nut and whichever occurs
ballscrew and first (depending on
attachment (Gimbal) the airplane
fittings. configuration).
Repetitive Within 500 or 2,000
lubrications of the flight hours or 2
ball nut and months or 1 year
ballscrew and from the last
attachment (Gimbal) lubrication,
fittings. whichever occurs
first, and
thereafter at
intervals not to
exceed 500 or 2,000
flight hours or 2
months or 1 year,
whichever occurs
first (depending on
the airplane
configuration).
Repetitive repair/ Before the
overhaul. accumulation of
20,000 flight hours
or 24,000 flight
hours since the
date of issuance of
the original
standard
airworthiness
certificate or the
date of issuance of
the original export
certificate of
airworthiness, or
within 20,000
flight hours or
24,000 flight hours
since the last
overhaul of the
trim actuator of
the horizontal
stabilizer,
whichever occurs
first (depending on
the airplane
configuration); and
thereafter at
intervals not to
exceed 20,000 or
25,000 flight
cycles (depending
on the airplane
configuration).
Installation of tube Before the
retainers on the accumulation of
ball nut. 24,000 flight hours
since the date of
issuance of the
original standard
airworthiness
certificate or the
date of issuance of
the original export
certificate of
airworthiness, or
within 24,000
flight hours since
the last overhaul
of the trim
actuator of the
horizontal
stabilizer,
whichever occurs
first.
Installation of a Before the
grease fitting. accumulation of
20,000 flight hours
since the date of
issuance of the
original standard
airworthiness
certificate or the
date of issuance of
the original export
certificate of
airworthiness, or
within 20,000
flight hours since
the last overhaul
of the trim
actuator of the
horizontal
stabilizer,
whichever occurs
first.
Installation of new Before the
ball deflectors and accumulation of
guide clamps for 24,000 flight hours
the ball return. since the date of
issuance of the
original standard
airworthiness
certificate or the
date of issuance of
the original export
certificate of
airworthiness, or
within 24,000
flight hours since
the last overhaul
of the trim
actuator of the
horizontal
stabilizer,
whichever occurs
first.
Installation of new Before the
return tube clamps. accumulation of
20,000 flight hours
since the date of
issuance of the
original standard
airworthiness
certificate or the
date of issuance of
the original export
certificate of
airworthiness, or
within 20,000
flight hours since
the last overhaul
of the trim
actuator of the
horizontal
stabilizer,
whichever occurs
first.
[[Page 22843]]
Applicable Before further
corrective actions. flight.
The corrective
actions include
repairing/replacing
discrepant parts.
------------------------------------------------------------------------
Table.--Secondary Service Bulletins
------------------------------------------------------------------------
Boeing Alert Service Bulletin-- Refers to--
------------------------------------------------------------------------
737-27A1277, Revision 1, dated July 25, UMBRA CUSCINETTI Service
2007 (for Model 737-600, -700, -700C, - Bulletin 07322-27-01, dated
800, -900, and -900ER series December 21, 2004, as an
airplanes). additional source of service
information for installing
tube retainers on the ball
nut.
737-27A1278, dated May 24, 2007 (for UMBRA CUSCINETTI Service
Model 737-100, -200, -200C, -300, - Bulletin 07322-27-01, dated
400, and -500 series airplanes). December 21, 2004, as an
additional source of service
information for installing
tube retainers on the ball
nut.
Boeing 737 Service Bulletin 27-
1046, Revision 1, dated April
5, 1974, as an additional
source of service information
for installing a grease
fitting.
Linear Motion Service Bulletin
7901708, Revision A, dated
July 26, 2005, as an
additional source of service
information for installing new
ball deflectors and guide
clamps for the ball return.
SKYTRONICS Service Bulletin
93004, dated September 1,
2005, as an additional source
of service information for
installing new return tube
clamps.
------------------------------------------------------------------------
FAA's Determination and Requirements of This Proposed AD
We are proposing this AD because we evaluated all relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other products of the(se) same type
design(s). This proposed AD would require accomplishing the actions
specified in the primary service bulletins described previously.
Clarification of Applicability of This AD
Boeing has informed us that Model 737-900ER series airplanes were
not specifically identified by model name in the Effectivity section of
Boeing Alert Service Bulletin 737-27A1277. However, those airplanes are
identified by variable numbers in the Effectivity section. Therefore,
this AD refers to Model 737-900ER series airplanes where appropriate.
Costs of Compliance
We estimate that this proposed AD would affect 1,602 Model 737
airplanes of U.S. registry. The following table provides the estimated
costs for U.S. operators to comply with this proposed AD.
Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
Average Number of
labor U.S.-
Action \1\ Work hours \1\ rate per Parts Cost per product \1\ registered Fleet cost \1\
hour airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Detailed inspections.................. 2 or 4................... $80 None $160 or $320, per 1,602 Between $256,320, and
inspection cycle. $512,640 per inspection
cycle.
Lubrications.......................... 1 or 3................... 80 None $80 or $240, per 1,602 Between $128,160, and
lubrication cycle. $384,480 per
lubrication cycle.
Repairs/overhauls..................... 40....................... 80 None $3,200 per repair/ 1,602 $5,126,400 per repair/
overhaul. overhaul cycle.
Installations......................... Between 1 and 3.......... 80 $2,200 Between $2,280 and $2,440 1,320 Between $3,009,600 and
$3,220,800.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Depending on airplane configuration.
The number of work hours, as indicated above, is presented as if
the accomplishment of the actions in this proposed AD is to be
conducted as new ``stand alone'' actions. However, in actual practice,
the lubrications, detailed inspections, and overhauls are currently
being done as part of normal airplane maintenance. The repair can be
done coincidentally or in combination with the normally scheduled HSTA
and ballscrew overhaul. Therefore, the actual number of necessary
additional work hours will be minimal in many instances. Additionally,
any costs associated with special airplane scheduling will be minimal.
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
[[Page 22844]]
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.
Regulatory Findings
We determined that this proposed AD would not have federalism
implications under Executive Order 13132. 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 this 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.
You can find our regulatory evaluation and the estimated costs of
compliance in the AD Docket.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA proposes to amend 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. The FAA amends Sec. 39.13 by adding the following new AD:
Boeing: Docket No. FAA-2008-0415; Directorate Identifier 2007-NM-
256-AD.
Comments Due Date
(a) We must receive comments by June 12, 2008.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Boeing airplanes identified in Table 1 of
this AD, certificated in any category.
Table 1.--Applicability
------------------------------------------------------------------------
As identified in Boeing Alert
Boeing model-- Service Bulletin--
------------------------------------------------------------------------
(1) 737-100, -200, -200C, -300, -400, 737-27A1278, dated May 24,
and -500 series airplanes. 2007.
(2) 737-600, -700, -700C, -800, -900, 737-27A1277, Revision 1, dated
and -900ER series airplanes. July 25, 2007.
------------------------------------------------------------------------
Unsafe Condition
(d) This AD results from a report of extensive corrosion of a
ballscrew in the drive mechanism of the horizontal stabilizer trim
actuator (HSTA). We are issuing this AD to prevent an undetected
failure of the primary load path for the ballscrew in the drive
mechanism of the HSTA and subsequent wear and failure of the
secondary load path, which could lead to loss of control of the
horizontal stabilizer and consequent loss of control of the
airplane.
Compliance
(e) Comply with this AD within the compliance times specified,
unless already done.
Service Bulletins
(f) The term ``service bulletin,'' as used in this AD, means the
applicable service bulletins specified in Table 2 of this AD.
Table 2.--Service Bulletins
------------------------------------------------------------------------
Boeing Alert Service Bulletin-- For model--
------------------------------------------------------------------------
(1) 737-27A1278, dated May 24, 2007.... 737-100, -200, -200C, -300, -
400, and -500 series
airplanes.
(2) 737-27A1277, Revision 1, dated July 737-600, -700, -700C, -800, -
25, 2007. 900, and -900ER series
airplanes.
------------------------------------------------------------------------
Note 1: The service bulletins refer to UMBRA CUSCINETTI Service
Bulletin 07322-27-01, dated December 21, 2004; Linear Motion Service
Bulletin 7901708, Revision A, dated July 26, 2005; Boeing 737
Service Bulletin 27-1046, Revision 1, dated April 5, 1974; and/or
SKYTRONICS Service Bulletin 93004, dated September 1, 2005, as
applicable, as additional sources of service information for
accomplishing the specified actions.
Inspections, Lubrications, Repairs/Overhauls, and Applicable Corrective
Actions
(g) At the applicable compliance time and repeat intervals
listed in Tables 1 and 2 of paragraph 1.E., ``Compliance,'' of the
service bulletin, do the inspections, lubrications, repairs/
overhauls, installation(s), and applicable corrective actions by
accomplishing all the applicable actions specified in the
Accomplishment Instructions of the service bulletin; except as
provided by paragraphs (g)(1) through (g)(3) of this AD.
(1) Where paragraph 1.E., ``Compliance,'' of the service
bulletin specifies an initial compliance time for accomplishing the
initial inspection, lubrication, or repair/overhaul, this AD
requires doing the applicable initial action(s) at the later of the
times specified in paragraphs (g)(1)(i) and (g)(1)(ii) of this AD.
(i) At the applicable compliance time specified in paragraph
1.E., ``Compliance,'' of the service bulletin.
(ii) Within the applicable compliance time specified in
paragraph (g)(1)(ii)(A), (g)(1)(ii)(B), or (g)(1)(ii)(C) of this AD.
(A) For the initial detailed inspection and lubrication: Within
6 months after the effective date of this AD.
(B) For the initial repair/overhaul: Within 12 months after the
effective date of this AD.
(C) For the installation(s): Within 12 months after the
effective date of this AD.
(2) Where Table 2 of paragraph 1.E., ``Compliance,'' of Boeing
Alert Service Bulletin 737-27A1277, Revision 1, dated July 25, 2007,
specifies a compliance time of ``* * * within 25,000 Flight Hours
since the latest horizontal stabilizer trim actuator (HSTA) Overhaul
from the date of Revision 1 of this Service Bulletin * * *,'' this
AD
[[Page 22845]]
requires compliance ``* * * within 25,000 flight hours since the
last overhaul of the trim actuator of the horizontal stabilizer.''
(3) Where Work Package 4, paragraphs 1.a., 2.a., and 3.a., of
the Accomplishment Instructions of Boeing Alert Service Bulletin
737-27A1278, dated May 24, 2007, specifies to identify the HSTA name
plate ``* * * AS GIVEN IN SB 737-27A1278, WORK PACKAGE 3,'' this AD
requires that identification `` * * * AS GIVEN IN SB 737-27A1278,
WORK PACKAGE 4.''
(4) Where Note (b) of Figures 7 through 9 of Boeing Alert
Service Bulletin 737-27A1278, dated May 24, 2007, specifies to do a
``* * * Backlash Inspection as given in AMM 27-41-81/606,'' this AD
requires an ``* * * End Play Test as given in OHM 27-45-11 page
701.''
(h) Actions done before the effective date of this AD in
accordance with Boeing Alert Service Bulletin 737-27A1277, dated
July 21, 2005, are acceptable for compliance with the corresponding
requirements of this AD.
Alternative Methods of Compliance (AMOCs)
(i)(1) The Manager, Seattle Aircraft Certification Office, FAA,
ATTN: Kelly McGuckin, Aerospace Engineer, Systems and Equipment
Branch, ANM-130S, FAA, Seattle Aircraft Certification Office, 1601
Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425)
917-6490; fax (425) 917-6590; has the authority to approve AMOCs for
this AD, if requested using the procedures found in 14 CFR 39.19.
(2) To request a different method of compliance or a different
compliance time for this AD, follow the procedures in 14 CFR 39.19.
Before using any approved AMOC on any airplane to which the AMOC
applies, notify your appropriate principal inspector (PI) in the FAA
Flight Standards District Office (FSDO), or lacking a PI, your local
FSDO.
Issued in Renton, Washington, on April 17, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E8-9193 Filed 4-25-08; 8:45 am]
BILLING CODE 4910-13-P
