[Federal Register: April 8, 2009 (Volume 74, Number 66)]
[Proposed Rules]
[Page 15896-15899]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr08ap09-21]
[[Page 15896]]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2009-0328; Directorate Identifier 2008-NE-44-AD]
RIN 2120-AA64
Airworthiness Directives; General Electric Company (GE) CF34-1A,
CF34-3A, and CF34-3B Series Turbofan Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for GE CF34-1A, CF34-3A, and CF34-3B series turbofan engines. This
proposed AD would require: Removing from service certain part number
(P/N) and serial number (SN) fan blades within compliance times
specified in this proposed AD, inspecting the fan blade abradable rub
strip on certain engines for wear, inspecting the fan blades on certain
engines for cracks, and inspecting the aft actuator head hose fitting
for correct position, and if necessary repositioning. This proposed AD
results from a report of an under-cowl fire, and a failed fan blade. We
are proposing this AD to prevent failure of certain P/N and SN fan
blades and aft actuator head hoses, which could result in an under-cowl
fire and subsequent damage to the airplane.
DATES: We must receive any comments on this proposed AD by June 8,
2009.
ADDRESSES: Use one of the following addresses to comment on this
proposed AD.
Federal eRulemaking Portal: Go to http://
www.regulations.gov and follow the instructions for sending your
comments electronically.
Mail: Docket Management Facility, U.S. Department of
Transportation, 1200 New Jersey Avenue, SE., West Building Ground
Floor, Room W12-140, Washington, DC 20590-0001.
Hand Delivery: Deliver to Mail address above between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
Fax: (202) 493-2251.
You can get the service information identified in this proposed AD
from General Electric Company via Lockheed Martin Technology Services,
10525 Chester Road, Suite C, Cincinnati, Ohio 45215, telephone (513)
672-8400, fax (513) 672-8422.
FOR FURTHER INFORMATION CONTACT: Kenneth Steeves, Aerospace Engineer,
Engine Certification Office, FAA, Engine & Propeller Directorate, 12
New England Executive Park, Burlington, MA 01803; e-mail:
kenneth.steeves@faa.gov; telephone (781) 238-7765; fax (781) 238-7199.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send us any written relevant data, views, or
arguments regarding this proposal. Send your comments to an address
listed under ADDRESSES. Include ``Docket No. FAA-2009-0328; Directorate
Identifier 2008-NE-44-AD'' in the subject line 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 http://
www.regulations.gov, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact
with FAA personnel concerning this proposed AD. Using the search
function of the Web site, anyone can find and read the comments in any
of our dockets, including, if provided, the name of the individual who
sent the comment (or signed the comment on behalf of an association,
business, labor union, etc.). You may review the DOT's complete Privacy
Act Statement in the Federal Register published on April 11, 2000 (65
FR 19477-78).
Examining the AD Docket
You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Operations office
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 Operations office (telephone (800) 647-5527) is
the same as the Mail address provided in the ADDRESSES section.
Comments will be available in the AD docket shortly after receipt.
Discussion
We have received reports of certain P/N and SN fan blades failing
on CF34 series engines. The first failure also included an under-cowl
fire that caused extensive damage to the engine. Although we haven't
been able to determine the exact cause of the under-cowl fire because
of the thermal damage, the investigation revealed two problems; a fan
blade failed at the platform tang and the aft actuator head hose
failed. The investigation also revealed that the accessory gearbox had
separated from the engine, possibly contributing to the actuator hose
failure.
We traced the failed fan blades to a specific supplier and their
billet material. The investigation found that the billet alloy material
met specifications and the supplier's approved processes were different
from other suppliers' approved processes. The differences allowed a
larger area of aligned alpha colonies to form in the tang region of the
fan blade. If the alpha colonies align, they can cause cracks in the
blade tang. Although the material was within specification, and the
processes and billet size conformed to the engineering drawings for the
blades, GE determined that the material, process, and billet size
combined to allow the alpha colonies to align. The investigation also
found that although the aft actuator hose is designed to include enough
slack to prevent its failure if the gearbox separates from the engine,
the incorrect orientation of the aft actuator head hose fitting at the
main fuel control removed that slack. The incorrect position of the
fitting might have caused the hose to fail and contribute to fire.
This condition, if not corrected, could result in failure of
certain P/N and SN fan blades and aft actuator head hoses, which could
result in an under-cowl fire and subsequent damage to the airplane.
Relevant Service Information
We have reviewed and approved the technical contents of the
following GE Aircraft Engines Service Bulletins (SBs):
CF34-AL S/B 73-0046, Revision 02, dated August 27, 2008,
and CF34-BJ S/B 73-0062, Revision 02, dated August 27, 2008, that
provide instructions for inspecting the orientation of the aft actuator
hose assembly and the main fuel control.
CF34-AL S/B 72-0245, Revision 01, dated July 3, 2008,
CF34-BJ S/B 72-0229, Revision 01, dated July 30, 2008, and CF34-BJ S/B
72-0230, Revision 01, dated July 30, 2008, that provide instructions
for replacing certain existing blades, P/Ns 6018T30P14 and 4923T56G08,
that have a SN listed in Appendix A of those SBs.
CF34-AL S/B 72-0250, Revision 01, dated November 26, 2008,
and CF34-BJ S/B 72-0231, Revision 02, dated November 26, 2008, that
provide instructions for inspecting the fan case abradable rub strip
and fan blade tangs.
[[Page 15897]]
Differences Between the Proposed AD and the Manufacturer's Service
Information
Service Bulletin CF34-AL S/B 73-0046, Revision 02, dated
August 27, 2008 recommends performing the inspection at the next ``A''
check, but no later than 750 hours time-in-service (TIS). This proposed
AD would require performing the inspection within 750 hours TIS after
the effective date of the proposed AD.
Service Bulletin CF34-BJ S/B 73-0062, Revision 02, dated
August 27, 2008, recommends performing the inspection of the CF34-3A1
engines at the next scheduled 300 hour check, but no later than 600
hours. This proposed AD would require performing the inspection within
300 hours TIS after the effective date of the proposed AD.
Service Bulletin CF34-BJ S/B 73-0062, Revision 02, dated
August 27, 2008, recommends performing the inspection of the CF34-3B
engines at the next scheduled 400 hour check but no later than 800
hours TIS. This proposed AD would require performing the inspection
within 400 hours TIS after the effective date of the proposed AD.
Service Bulletin CF34-AL S/B 72-0250, Revision 01, dated
November 26, 2008, recommends inspection of the fan blades if there is
a continuous 360 degree rub indication. This proposed AD would require
the inspection of the fan blades if there is a continuous 360 degree
rub indication. The service bulletin also contains an alternate
compliance method using GE's remote diagnostics trend monitoring
program. This proposed AD does not include that alternate method.
FAA's Determination and Requirements of the Proposed AD
We have evaluated all pertinent information and identified an
unsafe condition that is likely to exist or develop on other products
of this same type design. We are proposing this AD, which would
require:
Removing from service certain P/N and SN blades within
compliance times specified in this proposed AD.
Inspecting the fan blade abradable rub strip on certain
engines for wear.
Inspecting the fan blades on certain engines for cracks.
Inspecting the aft actuator head hose fitting for correct
position, and if necessary, repositioning.
The proposed AD would require you to use the service information
described previously to perform these actions.
Costs of Compliance
We estimate that this proposed AD would affect 1,966 engines
installed on airplanes of U.S. registry. We estimate that the fan blade
inspection and replacement requirement would affect 300 of these
engines, and the actuator head hose inspection would affect 1,662
engines. We also estimate that it would take 0.5 work-hour per engine
to inspect the fan blade abradable rub strip, 6 work-hours per engine
to visually inspect the fan blades, 11 work-hours per engine to perform
an eddy current inspection of the fan blades, and 0.25 work-hour per
engine to inspect the actuator head hose fitting, and that the average
labor rate is $80 per work-hour. Required parts would cost $51,106,600.
Based on these figures, we estimate the total cost of the proposed AD
to U.S. operators to be $51,184,000.
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.
Regulatory Findings
We have 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 that the proposed AD:
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. Would not have a significant economic impact, positive or
negative, on a substantial number of small entities under the criteria
of the Regulatory Flexibility Act.
We prepared a regulatory evaluation of the estimated costs to
comply with this proposed AD. You may get a copy of this summary at the
address listed under ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
The Proposed Amendment
Under the authority delegated to me by the Administrator, the
Federal Aviation Administration 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
airworthiness directive:
General Electric Company: Docket No. FAA-2009-0328; Directorate
Identifier 2008-NE-44-AD.
Comments Due Date
(a) The Federal Aviation Administration (FAA) must receive
comments on this airworthiness directive (AD) action by June 8,
2009.
Affected ADs
(b) None.
Applicability
(c) This AD applies to General Electric Company (GE) CF34-1A,
CF34-3A, CF34-3A1, CF34-3A2, CF34-3B, and CF34-3B1 turbofan engines.
These engines are installed on, but not limited to, Bombardier
Canadair Models CL-600-2A12, CL-600-2B16, and CL-600-2B19 airplanes.
Unsafe Condition
(d) This AD results from a report of an under-cowl fire, and a
failed fan blade. We are issuing this AD to prevent failure of
certain part number (P/N) and serial number (SN) fan blades and aft
actuator head hoses, which could result in an under-cowl fire and
subsequent damage to the airplane.
Compliance
(e) You are responsible for having the actions required by this
AD performed within the compliance times specified unless the
actions have already been done.
CF34-3A1 and CF34-3B1 Engines
(f) For CF34-3A1 engines with fan drive shaft, P/N 6036T78P02,
and airworthiness limitation section life limit of 22,000 CSN, and
CF34-3B1 engines with fan blades, P/Ns 6018T30P14 or 4923T56G08,
that have a fan
[[Page 15898]]
blade SN listed in Appendix A of GE Aircraft Engines (GEAE) Service
Bulletin (SB) CF34-AL S/B 72-0245, Revision 01, dated July 3, 2008,
do the following:
(1) Remove fan blades from service within 4,000 cycles-in-
service (CIS) after the effective date of this AD or by December 31,
2010, whichever occurs first.
Initial Visual Inspection of the Fan Blade Abradable Rub Strip for Wear
(2) For fan blades with 1,200 or more cycles-since-new (CSN) on
the effective date of this AD, within 20 CIS after the effective
date of this AD, perform an initial visual inspection of the fan
blade abradable rub strip for wear. Use paragraphs 3.A.(1) through
3.A.(2) of the Accomplishment Instructions of GEAE SB CF34-AL S/B
72-0250, Revision 01, dated November 26, 2008, to perform the
inspection.
(3) For fan blades with fewer than 1,200 CSN on the effective
date of this AD, within 1,220 CSN, perform an initial visual
inspection of the fan blade abradable rub strip for wear. Use
paragraphs 3.A.(1) through 3.A.(2) of the Accomplishment
Instructions of GEAE SB CF34-AL S/B 72-0250, Revision 01, dated
November 26, 2008, to perform the inspection.
(4) If you find a continuous 360 degree rub indication, before
further flight, visually inspect the fan blades using paragraphs
3.A.(2)(a) through 3.A.(2)(b) of the Accomplishment Instructions of
GEAE SB CF34-AL S/B 72-0250, Revision 01, dated November 26, 2008,
to perform the inspection.
(5) If you find a crack in the retaining pin holes of the fan
blade, remove the blade from service.
Repetitive Visual Inspection of the Fan Blade Abradable Rub Strip for
Wear
(6) Within 75 cycles-since-last inspection (CSLI) or 100 hours-
since-last-inspection (HSLI), whichever occurs later, perform a
visual inspection of the fan blade abradable rub strip for wear. Use
paragraphs 3.A.(1) through 3.A.(2) of the Accomplishment
Instructions of GEAE SB CF34-AL S/B 72-0250, Revision 01, dated
November 26, 2008, to perform the inspection.
(i) If you find a continuous 360 degree rub indication, before
further flight, visually inspect the fan blades using paragraphs
3.A.(2)(a) through 3.A.(2)(b) of the Accomplishment Instructions of
GEAE SB CF34-AL S/B 72-0250, Revision 01, dated November 26, 2008,
to perform the inspection.
(ii) If you find a crack in the retaining pin holes of the fan
blade, remove the blade from service.
Inspection of the Aft Actuator Head Hose Fitting on CF34-3A1 and CF34-
3B1 Engines
(7) Within 750 hours time in service (TIS) after the effective
date of this AD, visually inspect and, if necessary, reposition the
aft actuator head hose fitting. Use paragraph 3.A of the
Accomplishment Instructions of GEAE SB CF34-AL S/B 73-0046, Revision
02, dated August 27, 2008, to perform the inspection.
CF34-1A, CF34-3A, CF34-3A2, CF34-3B, and CF34-3A1 Engines
(g) For CF34-3A1 engines with fan drive shaft, P/N 6036T78P02,
and airworthiness limitation section life limit of 15,000 CSN, and
CF34-1A, CF34-3A, CF34-3A2, and CF34-3B engines with fan blades, P/N
6018T30P14 or P/N 4923T56G08, that have a fan blade SN listed in
Appendix A of GEAE SB CF34-BJ S/B 72-0229, Revision 01, dated July
30, 2008, do the following:
(1) Remove fan blades, P/N 6018T30P14, from service within 2,400
CSN.
(2) Remove fan blades, P/N 4923T56G08, from service within 1,200
CIS since the bushing repair of the fan blade hole.
Initial Eddy Current Inspection of the Fan Blades
(3) For fan blades, P/N 6018T30P14, with more than 850 CSN, but
fewer than 1,200 CSN on the effective date of this AD, within 350
CIS after the effective date of this AD, perform an initial eddy
current inspection (ECI) of the fan blades for cracks. Use
paragraphs 3.A. or 3.B. of the Accomplishment Instructions of GEAE
SB CF34-BJ S/B 72-0229, Revision 01, dated July 30, 2008, to perform
the inspection.
(4) For fan blades, P/N 6018T30P14, with 850 or fewer CSN on the
effective date of this AD, within 1,200 CSN, perform an initial ECI
of the fan blades for cracks. Use paragraphs 3.A. or 3.B. of the
Accomplishment Instructions of GEAE SB CF34-BJ S/B 72-0229, Revision
01, dated July 30, 2008, to perform the inspection.
(5) If you find a crack in the retaining pin holes of the fan
blade, remove the blade from service.
Repetitive ECI of the Fan Blades
(6) For fan blades, P/N 6018T30P14, installed, within 600 CSLI,
perform an ECI of the fan blades for cracks. Use paragraphs 3.A. or
3.B. of the Accomplishment Instructions of GEAE SB CF34-BJ S/B 72-
0229, Revision 01, dated July 30, 2008, to perform the inspection.
(7) If you find a crack in the retaining pin holes of the fan
blade, remove the blade from service.
Initial Visual Inspection of the Fan Blade Abradable Rub Strip for Wear
(8) For engines with fan blades, P/N 6018T30P14, installed that
have a fan blade SN listed in Appendix A of GEAE SB CF34-BJ S/B 72-
0229, Revision 01, dated July 30, 2008, with 1,200 or more CSN on
the effective date of this AD, that haven't had an ECI of the fan
blades for cracks, do the following:
(i) Perform an initial inspection of the fan blade abradable rub
strip for wear within 20 CIS after the effective date of this AD.
Use paragraph 3.A.(1) of the Accomplishment Instructions of GEAE SB
CF34-BJ S/B 72-0231, Revision 02, dated November 26, 2008, to
perform the inspection.
(ii) If you find a continuous 360 degree rub indication, before
further flight, perform a visual inspection of the fan blades for
cracks. Use paragraphs 3.A(2)(a) or 3.A(2)(b) of the Accomplishment
Instructions of GEAE SB CF34-BJ S/B 72-0231, Revision 02, dated
November 26, 2008, to perform the inspection.
(iii) If you find a crack in the retaining pin holes of the fan
blade, remove the blade from service.
Repetitive Inspection of the Fan Blade Abradable Rub Strip for Wear
(9) For engines with fan blades, P/N 6018T30P14, installed, if
you have performed an ECI of the fan blade, you don't need to
inspect the fan blade abradable rub strip for wear.
(10) For engines with fan blades, P/N 6018T30P14, installed,
within 75 CSLI or 100 HSLI, whichever occurs later, do the
following:
(i) Perform a visual inspection of the fan blade abradable rub
strip for wear. Use paragraph 3.A.(1) of the Accomplishment
Instructions of GEAE SB CF34-BJ S/B 72-0231, Revision 02, dated
November 26, 2008, to perform the inspection.
(ii) If you find a continuous 360 degree rub indication, before
further flight, visually inspect the fan blades using paragraphs
3.A.(2)(a) through 3.A.(2)(b) of the Accomplishment Instructions of
GEAE SB CF34-BJ S/B 72-0231, Revision 02, dated November 26, 2008.
(iii) If you find a crack in the retaining pin holes of the fan
blade, remove the blade from service.
Inspection of the Aft Actuator Head Hose Fitting on CF34-3A1 and CF34-
3B Engines
(11) For CF34-3A1 engines, within 300 hours TIS after the
effective date of this AD, visually inspect and, if necessary,
reposition the aft actuator head hose fitting. Use paragraph 3.A of
the Accomplishment Instructions of GEAE SB CF34-BJ S/B 73-0062,
Revision 02, dated August 27, 2008, to perform the inspection.
(12) For CF34-3B engines, within 400 hours TIS after the
effective date of this AD, visually inspect and if necessary,
reposition the aft actuator head hose fitting. Use paragraph 3.A of
the Accomplishment Instructions of GEAE SB CF34-BJ S/B 73-0062,
Revision 02, dated August 27, 2008, to perform the inspection.
Credit for Previous Actions
(h) Inspections previously performed using the following GEAE
SBs meet the requirements specified in the indicated paragraphs:
(1) CF34-AL S/B 72-0250, dated August 15, 2008, meet the
requirements specified in paragraphs (f)(2) through (f)(4) of this
AD.
(2) CF34-AL S/B 73-0046, Revision 01, dated July 1, 2008, or
earlier issue, meet the requirements specified in paragraph (f)(7)
of this AD.
(3) CF34-BJ S/B 72-0229, dated April 10, 2008, meet the
requirements specified in paragraphs (g)(3) and (g)(4) of this AD.
(4) CF34-BJ S/B 72-0231, Revision 01, dated October 1, 2008, or
earlier issue, meet the requirements specified in paragraphs
(g)(10)(i) and (g)(10)(ii) of this AD.
(5) CF34-BJ S/B 73-0062, Revision 01, dated July 1, 2008, or
earlier issue, meet the requirements specified in paragraphs (g)(11)
and (g)(12) of this AD.
[[Page 15899]]
Installation Prohibitions
(i) After the effective date of this AD:
(1) Do not install any fan blade into any CF34-3A1 engine with
fan drive shaft, P/N 6036T78P02, with an airworthiness limitation
section life limit of 22,000 CSN if that fan blade:
(i) Was installed in a CF34-3A1 engine with fan drive shaft, P/N
6036T78P02, with an airworthiness limitation section life limit of
15,000 CSN; and
(ii) Is listed in Appendix A of GEAE SB CF34-BJ S/B 72-0229,
Revision 01, dated July 30, 2008; or
(iii) Is listed in Appendix A of GEAE SB CF34-BJ S/B 72-0230,
Revision 01, dated July 30, 2008.
(2) Do not install any fan blade into any CF34-3A1 engine with
fan drive shaft, P/N 6036T78P02, with an airworthiness limitation
section life limit of 15,000 CSN if that fan blade:
(i) Was installed in any CF34-3A1 engine with fan drive shaft,
P/N 6036T78P02, with an airworthiness limitation section life limit
of 22,000 CSN and,
(ii) Is listed in Appendix A of GEAE SB CF34-AL S/B 72-0245,
Revision 01, dated July 3, 2008.
Alternative Methods of Compliance
(j) The Manager, Engine Certification Office, has the authority
to approve alternative methods of compliance for this AD if
requested using the procedures found in 14 CFR 39.19.
Related Information
(k) Contact Kenneth Steeves, Aerospace Engineer, Engine
Certification Office, FAA, Engine & Propeller Directorate, 12 New
England Executive Park, Burlington, MA 01803; e-mail:
kenneth.steeves@faa.gov; telephone (781) 238-7765; fax (781) 238-
7199, for more information about this AD.
(l) GE Aircraft Engines SBs CF34-AL S/B 73-0046, Revision 02,
dated August 27, 2008; CF34-AL S/B 72-0245, Revision 01, dated July
3, 2008; CF34-AL S/B 72-0250, dated August 15, 2008; CF34-BJ S/B 73-
0062, Revision 02, dated August 27, 2008; CF34-BJ S/B 72-0229,
Revision 01, dated July 30, 2008; CF34-BJ S/B 72-0230, Revision 01,
dated July 30, 2008; and CF34-BJ S/B 72-0231, Revision 01, dated
October 1, 2008; pertain to the subject of this AD. Contact General
Electric Company via Lockheed Martin Technology Services, 10525
Chester Road, Suite C, Cincinnati, Ohio 45215; telephone (513) 672-
8400; fax (513) 672-8422, for a copy of this service information.
Issued in Burlington, Massachusetts, on April 4, 2009.
Peter A. White,
Assistant Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. E9-8070 Filed 4-6-09; 11:15 am]
BILLING CODE 4910-13-P