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Start Preamble
Start Printed Page 8875
AGENCY:
Federal Aviation Administration (FAA), DOT.
ACTION:
Notice of proposed rulemaking (NPRM).
SUMMARY:
The FAA proposes to adopt a new airworthiness directive (AD) for General Electric Company (GE) CT58-140-1, CT58-140-2, and T58-GE-5, -10, -100, and -402 series turboshaft engines with certain serial numbers (SNs) of stage 1 compressor disks, part number (P/N) 5001T20P01, installed. This proposed AD would require removing certain stage 1 compressor disks from service before reaching a reduced low-cycle-fatigue (LCF) life limit. This proposed AD results from two reports of low blade tip clearances in the compressor. We are proposing this AD to prevent LCF cracking and failure of the stage 1 compressor disk, an uncontained engine failure, and damage to the helicopter.
DATES:
We must receive any comments on this proposed AD by April 26, 2004.
ADDRESSES:
Use one of the following addresses to submit comments on this proposed AD:
- By mail: Federal Aviation Administration (FAA), New England Region, Office of the Regional Counsel, Attention: Rules Docket No. 2003-NE-59-AD, 12 New England Executive Park, Burlington, MA 01803-5299.
- By fax: (781) 238-7055.
- By e-mail: 9-ane-adcomment@faa.gov
You can get the service information identified in this proposed AD from GE Aircraft Engines Customer Support Center, M/D 285, 1 Neumann Way, Evendale, OH 45215, telephone (513) 552-3272; fax (513) 552-3329, email GEAE.csc@ae.ge.com.
You may examine the AD docket, by appointment, at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA.
Start Further InfoFOR FURTHER INFORMATION CONTACT:
Norman Brown, Senior Engineer, Engine Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park; telephone (781) 238-7181; fax (781) 238-7199.
End Further Info End Preamble Start Supplemental InformationSUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to submit any written relevant data, views, or arguments regarding this proposal. Send your comments to an address listed under ADDRESSES. Include “AD Docket No. 2003-NE-59-AD” in the subject line of your comments. If you want us to acknowledge receipt of your mailed comments, send us a self-addressed, stamped postcard with the docket number written on it; we will date-stamp your postcard and mail it back to you. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. If a person contacts us verbally, and that contact relates to a substantive part of this proposed AD, we will summarize the contact and place the summary in the docket. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.
We are reviewing the writing style we currently use in regulatory documents. We are interested in your comments on whether the style of this document is clear, and your suggestions to improve the clarity of our communications that affect you. You can get more information about plain language at http://www.faa.gov/language and http://www.plainlanguage.gov.
Examining the AD Docket
You may examine the AD Docket (including any comments and service information), by appointment, between 8 a.m. and 4:30 p.m., Monday through Friday, except Federal holidays. See ADDRESSES for the location.
Discussion
On May 1, 2003, GE informed the FAA that 320 stage 1 compressor disks, P/N 5001T20P01, have high-peak stresses. GE has identified the affected stage 1 compressor disks by SN. An investigation by GE revealed that the tangential positioning of the blade dovetail slot resulted in the high-peak stresses. This proposed AD would require removing those stage 1 compressor disks, PN 5001T20P01, from service before reaching a reduced LCF life limit of 2,100 hours time-since-new (TSN) or by December 31, 2008, whichever occurs first. This condition, if not corrected, could result in LCF cracking and failure of the stage 1 compressor disk, an uncontained engine failure, and damage to the helicopter.
Relevant Service Information
We have reviewed and approved the technical contents of GE Alert Service Bulletin (ASB) No. CT58 S/B 72-A0196, dated July 24, 2003, that describes the procedures for replacing the stage 1 compressor disk.
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. Therefore, we are proposing this AD which would require removing certain stage 1 compressor disks from service at or before reaching a reduced LCF life limit of 2,100 hours TSN or by December 31, 2008, whichever occurs first.
Changes to 14 CFR Part 39—Effect on the Proposed AD
On July 10, 2002, we issued a new version of 14 CFR part 39 (67 FR 47998, July 22, 2002), which governs the FAA's AD system. This regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance. This material previously was included in each individual AD. Since this material is included in 14 CFR part 39, we will not include it in future AD actions.
Interim Action
These actions are interim actions and we may take further rulemaking actions in the future.
Costs of Compliance
There are about 320 GE CT58-140-1, CT58-140-2, and T58-GE-5, -10, -100, and -402 series turboshaft engines of Start Printed Page 8876the affected design in the worldwide fleet. We estimate that 45 engines installed on helicopters of U.S. registry would be affected by this proposed AD. The proposed action does not impose any additional labor costs. A new disk would cost about $7,965 per engine. We estimate that the prorated cost of the life reduction would be about $4,181 per engine. Based on these figures, we estimate the total cost of the proposed AD to U.S. operators to be $188,172.
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 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. 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 summary of the costs to comply with this proposal and placed it in the AD Docket. You may get a copy of this summary by sending a request to us at the address listed under ADDRESSES. Include “AD Docket No. 2003-NE-59-AD” in your request.
Start List of SubjectsList 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 Federal Aviation Administration proposes to amend 14 CFR part 39 as follows:
Start PartPART 39—AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Start Signature[Amended]2. The FAA amends § 39.13 by adding the following new airworthiness directive:
General Electric Company: Docket No. 2003-NE-59-AD.
Comments Due Date
(a) The Federal Aviation Administration (FAA) must receive comments on this airworthiness directive (AD) action by April 26, 2004.
Affected ADs
(b) None.
Applicability
(c) This AD applies to General Electric Company (GE) CT58-140-1, CT58-140-2, and T58-GE-5, -10, -100, and -402 series turboshaft engines with stage 1 compressor disks, part number (P/N) 5001T20P01, that have a serial number (SN) listed in the following Table 1:
Table 1.—Stage 1 Compressor Disk SNs Affected By This AD
GATD0PD2 GATH6RWW GATH7PR0 GATH86K2 GATH8K0P GATD0PD3 GATH6T00 GATH7PR1 GATH86K3 GATH8K0R GATD0PD5 GATH6T01 GATH7PR2 GATH86K4 GATH8K0T GATD0PD6 GATH6T02 GATH7PR3 GATH86K5 GATH8K0W GATD0PD7 GATH6T03 GATH7PR4 GATH8A5G GATH8K12 GATD0PD8 GATH6T04 GATH7PR5 GATH8A5H GATH8K13 GATD0PD9 GATH6T05 GATH7PR6 GATH8A5J GATH8K14 GATD0PDA GATH7K4K GATH7PR7 GATH8A5K GATH8K15 GATD0PDC GATH7K4L GATH7PR8 GATH8A5L GATH8K16 GATH53GC GATH7K4M GATH7PR9 GATH8A5M GATH8K17 GATH53GD GATH7K4N GATH7PRA GATH8A5N GATH8K18 GATH53GE GATH7K4P GATH7PRC GATH8A5P GATH8K19 GATH53GF GATH7K4R GATH7PRD GATH8A5T GATH8W7H GATH53GH GATH7K4T GATH7PRE GATH8A5W GATH8W7J GATH53GJ GATH7K5G GATH7PRF GATH8A60 GATH8W7L GATH53GK GATH7KGH GATH7PRG GATH8A61 GATH8W7M GATH5T70 GATH7KGK GATH7PRH GATH8A62 GATH8W7N GATH5T71 GATH7KGL GATH7PRJ GATH8A63 GATH8W7P GATH5T72 GATH7KGM GATH7PRK GATH8A64 GATH8W7R GATH5T73 GATH7KGN GATH7PRL GATH8A66 GATH8W7T GATH5T74 GATH7KGP GATH7PRM GATH8A67 GATH8WD4 GATH5T75 GATH7KGR GATH7PRN GATH8A68 GATH8WD5 GATH5T76 GATH7KGT GATH7PRP GATH8GRG GATH8WD6 GATH5T77 GATH7KGW GATH7PRR GATH8GRH GATH8WD7 GATH5T78 GATH7KH0 GATH7PRT GATH8GRK GATH8WD8 GATH5T79 GATH7KH1 Start Printed Page 8877 GATH7PRW GATH8GRL GATH8WD9 GATH5T7A GATH7KH2 GATH7PT0 GATH8GRM GATH8WDA GATH5T7C GATH7LAL GATH7RTP GATH8GRN GATH8WDC GATH5T7D GATH7LAM GATH7RTR GATH8GRP GATH8WDD GATH5T7E GATH7LAN GATH7RTT GATH8GRR GATH8WDE GATH5T7F GATH7LAP GATH82R8 GATH8GRT GATH8WDF GATH5T7G GATH7LAR GATH82R9 GATH8GRW GATH8WDG GATH5T7H GATH7LAT GATH82RA GATH8GT0 GATH8WDH GATH6CDL GATH7LAW GATH82RD GATH8GT1 GATH8WDJ GATH6CDM GATH7LC0 GATH82RE GATH8GT3 GATH8WDK GATH6CDN GATH7LC1 GATH82RF GATH8GT5 GATH8WDL GATH6CDP GATH7LC2 GATH82RG GATH8GT7 GATH94R3 GATH6CDR GATH7LC3 GATH82RH GATH8GT8 GATH94R4 GATH6CDT GATH7LC4 GATH82RJ GATH8HGF GATH94R6 GATH6CE0 GATH7LC5 GATH82RK GATH8HGG GATH94R7 GATH6CE1 GATH7LC6 GATH82RL GATH8HGH GATH94R8 GATH6CE2 GATH7LC7 GATH82RM GATH8HGJ GATH94R9 GATH6CE3 GATH7LC8 GATH82RN GATH8HGK GATH94RA GATH6CE4 GATH7M8G GATH82RP GATH8HGL GATH94RC GATH6CE5 GATH7M8H GATH82RR GATH8HGM GATH94RD GATH6CE6 GATH7M8J GATH82RT GATH8HGN GATH94RE GATH6CE7 GATH7M8K GATH82RW GATH8HGP GATH94RF GATH6CE8 GATH7M8L GATH82T0 GATH8HGR GATH94RG GATH6CE9 GATH7M8M GATH82T1 GATH8HGT GATH94RJ GATH6CEA GATH7M8N GATH86JD GATH8HGW GATH94RK GATH6CEC GATH7MLK GATH86JE GATH8HH0 GATH94RN GATH6CED GATH7MLL GATH86JF GATH8HH1 GATH94RP GATH6CEE GATH7MLM GATH86JG GATH8HH2 GATH94RR GATH6CEF GATH7MLN GATH86JH GATH8HH3 GATH94RT GATH6RH8 GATH7MLP GATH86JJ GATH8HH4 GATH96HF GATH6RH9 GATH7MLR GATH86JK GATH8HH5 GATH96HG GATH6RHC GATH7MLT GATH86JL GATH8HH6 GATH96HK GATH6RHD GATH7MLW GATH86JM GATH8HH7 GATH96HL GATH6RHE GATH7MM0 GATH86JN GATH8K0H GATH96HM GATH6RHF GATH7MM1 GATH86JP GATH8K0J GATH96HN GATH6RHG GATH7MM2 GATH86JR GATH8K0K GATH96HR GATH6RHH GATH7MM3 GATH86JT GATH8K0L GATH96HT GATH6RHJ GATH7PPT GATH86JW GATH8K0M GATH96HW GATH6RWT GATH7PPW GATH86K0 GATH8K0N GATH96J0 These engines are installed on, but not limited to Agusta S.p.A AS-61N, AS-61N1, Sikorsky S-61L, S-61N, S-61R, and S-61NM helicopters, and the following surplus military helicopters that have been certified in accordance with sections 21.25 or 21.27 of the Federal Aviation Regulations (14 CFR 21.25 or 21.27): Sikorsky S-61D and S-61V, Glacier CH-3E, Siller CH-3E and SH-3A, and Robinson Crane CH-3C, CH-3E, HH-3C, HH-3E, and Carson S-61L helicopters.
Unsafe Condition
(d) This AD results from two reports of low blade tip clearances in the compressor. We are issuing this AD to prevent low-cycle-fatigue (LCF) cracking and failure of the stage 1 compressor disk, an uncontained engine failure, and damage to the helicopter. Start Printed Page 8878
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.
Replacement of Stage 1 Compressor Disks
(f) If you have a stage 1 compressor disk, P/N 5001T20P01, with a SN listed in Table 1 of this AD, replace that stage 1 compressor disk at or before reaching a reduced LCF life limit of 2,100 hours time-since-new (TSN) or by December 31, 2008, whichever occurs first. GE Alert Service Bulletin (ASB) No. CT58 S/B 72-A0196, dated July 24, 2003, contains information on replacing the stage 1 compressor disk.
(g) After the effective date of this AD, do not install any stage 1 compressor disk, P/N 5001T20P01, that has a SN listed in Table 1 of this AD and has 2,100 hours TSN or more, into any engine.
Alternative Methods of Compliance
(h) 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.
Material Incorporated by Reference
(i) None.
Related Information
(j) GE Alert Service Bulletin (ASB) No. CT58 S/B 72-A0196, dated July 24, 2003, pertains to the subject of this AD.
End Signature End Part End Supplemental InformationIssued in Burlington, Massachusetts, on February 17, 2004.
Francis A. Favara,
Acting Manager, Engine and Propeller Directorate, Aircraft Certification Service.
[FR Doc. 04-4101 Filed 2-25-04; 8:45 am]
BILLING CODE 4910-13-U
Document Information
- Published:
- 02/26/2004
- Department:
- Federal Aviation Administration
- Entry Type:
- Proposed Rule
- Action:
- Notice of proposed rulemaking (NPRM).
- Document Number:
- 04-4101
- Dates:
- We must receive any comments on this proposed AD by April 26, 2004.
- Pages:
- 8875-8878 (4 pages)
- Docket Numbers:
- Docket No. 2003-NE-59-AD
- RINs:
- 2120-AA64: Airworthiness Directives
- RIN Links:
- https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives
- Topics:
- Air transportation, Aircraft, Aviation safety, Safety
- PDF File:
- 04-4101.pdf
- CFR: (1)
- 14 CFR 39.13