Airworthiness Directives: General Electric Co. Aircraft Engines CT7-8A Turboshaft Engines
Federal Register: March 19, 2008 (Volume 73, Number 54)
Proposed Rules
Page 14731-14733
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
DOCID:fr19mr08-26
Proposed Rules
Federal Register
This section of the FEDERAL REGISTER contains notices to the public of the proposed issuance of rules and regulations. The purpose of these notices is to give interested persons an opportunity to participate in the rule making prior to the adoption of the final rules.
Page 14731
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration 14 CFR Part 39
Docket No. FAA-2006-24261; Directorate Identifier 2006-NE-12-AD
RIN 2120-AA64
Airworthiness Directives; General Electric Company Aircraft
Engines (GEAE) CT7-8A Turboshaft Engines
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Notice of proposed rulemaking (NPRM).
SUMMARY: The FAA proposes to supersede an existing airworthiness directive (AD) for certain GEAE CT7-8A turboshaft engines. That AD currently requires initial and repetitive inspections of the electrical chip detectors for the No. 3 bearing. This proposed AD would require removing certain GEAE CT7-8A turboshaft engines within 6,200 cycles- since-new. This proposed AD results from investigation for the root causes of two failures of the No. 3 bearing. We are proposing this AD to prevent failure of the No. 3 bearing due to contamination by
Aluminum Oxide, which could result in a possible dual in-flight shutdown of the engines.
DATES: We must receive any comments on this proposed AD by May 19, 2008.
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.
Contact General Electric Aircraft Engines CT7 Series Turboprop
Engines, 1000 Western Ave., Lynn, MA 01910; telephone (781) 594-3140, fax (781) 594-4805, for the service information identified in this proposed AD.
FOR FURTHER INFORMATION CONTACT: Christopher Richards, Aerospace
Engineer, Engine Certification Office, FAA, Engine and Propeller
Directorate, 12 New England Executive Park, Burlington, MA 01803; e- mail: christopher.j.richards@faa.gov; telephone (731) 238-7133; fax
(781) 238-7199.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include ``Docket No. FAA-2006-24261;
Directorate Identifier 2006-NE-12-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 DMS Web site, anyone can find and read the comments in any of our dockets, including 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) or you may visit http://www.regulations.gov.
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
The FAA proposes to amend 14 CFR part 39 by superseding AD 2006-06- 51, Amendment 39-14566 (71 FR 19627, April 17, 2006). That AD requires:
Within 25 hours time-in-service after the effective date of that AD, inspecting the electrical chip detector assembly.
Staggering the inspection intervals so the chip detectors on both engines on the same helicopter are not inspected at the same time.
Thereafter, within 25 hours time-since-last inspection, performing a repetitive inspection, and
If the chip detector assembly contains any bearing material, replacing the engine.
That AD was the result of two failures of the No. 3 bearing in GEAE
CT7-8A turboshaft engines. That condition, if not corrected, could result in a possible dual in-flight shutdown of the engines.
Actions Since AD 2006-06-51 Was Issued
Since we issued that AD, GEAE has developed new procedures for flushing Aluminum Oxide hard particle contamination from the air cavity of the engine structure's front frame after the manufacturing process and for assembling the No. 3 bearing to the engine. Based on that new flushing procedure, we are proposing to:
Delete the requirements to inspect the electrical chip detector, and
Require removing any engine that has a serial number (SN) listed in Table 1 of this proposed AD unless the front frame was flushed and the No. 3 bearing replaced, and
Prohibit installing any engine that has a SN listed in
Table 1 of this proposed AD unless the front frame was flushed and the
No. 3 bearing replaced.
Relevant Service Information
We have reviewed and approved the technical contents of GEAE
Service Bulletin (SB) CT7-8 S/B 72-0017, dated
Page 14732
October 18, 2007, that describes procedures for flushing the engine front frame and replacing the No. 3 bearing.
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. For that reason, we are proposing this AD, which would require removing certain GEAE CT7-8A turboshaft engines, listed by SN in this proposed AD, from service within 6,200 cycles- since-new, and, after the effective date of the proposed AD, would prohibit installing certain GEAE CT7-8A turboshaft engines, listed by
SN in this proposed AD.
Costs of Compliance
We estimate that this proposed AD would affect 29 engines installed on helicopters of U.S. registry. We also estimate that it would take about 66.0 work-hours per engine to perform the proposed actions, and that the average labor rate is $80 per work-hour. Required parts would cost about $3,476 per engine. Based on these figures, we estimate the total cost of the proposed AD to U.S. operators to be $253,924
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. See the ADDRESSES section for a location to examine the regulatory evaluation.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, 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 removing Amendment 39-14566 (71 FR 19627, April 17, 2006) and by adding a new airworthiness directive to read as follows:
General Electric Company Aircraft Engines: Docket No. FAA-2006- 24261; Directorate Identifier 2006-NE-12-AD.
Comments Due Date
(a) The Federal Aviation Administration (FAA) must receive comments on this airworthiness directive (AD) action by May 19, 2008.
Affected ADs
(b) This AD supersedes AD 2006-06-51, Amendment 39-14566.
Applicability
(c) This AD applies to General Electric Company Aircraft Engines
(GEAE) CT7-8A turboshaft engines that have a serial number (SN) listed in Table 1 of this AD. These engines are installed on, but not limited to, Sikorsky S92 helicopters.
Table 1.--Affected Engines by Serial Number
Engine Serial No.--------------------------------
947205
947228
947254 947206
947230
947255 947207
947232
947256 947208
947233
947258 947209
947235
947260 947210
947238
947261 947211
947240
947262 947212
947241
947263 947214
947242
947265 947215
947243
947266 947217
947244
947274 947218
947245
947277 947219
947247
947278 947220
947248
947279 947221
947249
947280 947223
947250
947284 947225
947253
947285
Unsafe Condition
(d) This AD results from investigation for the root causes of two failures of the No. 3 bearing. We are issuing this AD to prevent failure of the No. 3 bearing due to contamination by Aluminum Oxide, which could result in a possible dual in-flight shutdown of the engines.
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.
(f) No further action is required if:
(1) Your engine has an SN that is not listed in Table 1 of this
AD, or
(2) Your engine has an SN listed in Table 1 of this AD, but the engine log specifies that the front frame was flushed and the No. 3 bearing was replaced.
Engines With SNs Listed in Table 1 of This AD
(g) For engines with an SN listed in Table 1 of this AD, within 6,200 cycles-since-new, remove engine from service.
Installation Prohibition
(h) After the effective date of this AD, do not install any engine that has an SN listed in Table 1 of this AD unless the front frame was flushed and the No. 3 bearing was replaced. GEAE Service
Bulletin (SB) CT7-8 S/B 72-0017, dated October 18, 2007, contains information on flushing the front frame and replacing the No. 3 bearing.
Alternative Methods of Compliance
(i) The Manager, Engine Certification Office, FAA, 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
(j) GEAE SB No. CT7-8 S/B 72-0017, dated October 18, 2007, pertains to the subject of this AD.
(k) Contact Christopher Richards, Aerospace Engineer, Engine
Certification Office, FAA, Engine and Propeller Directorate, 12 New
England Executive Park,
Page 14733
Burlington, MA 01803; e-mail: christopher.j.richards@faa.gov; telephone (731) 238-7133; fax (781) 238-7199, for more information about this AD.
Issued in Burlington, Massachusetts, on March 12, 2008.
Robert J. Ganley,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
FR Doc. E8-5492 Filed 3-18-08; 8:45 am
BILLING CODE 4910-13-P
