AD 2001-12-07

This amendment adopts a new airworthiness directive (AD) that is applicable to certain General Electric Company (GE) CT58 series and former military T58 series turboshaft engines. This action requires the removal from service of certain fuel flow divider assemblies, and replacement with serviceable parts. This amendment is prompted by reports of large volumes of fuel leakage from end caps on fuel flow divider assemblies. The actions specified in this AD are intended to prevent fuel flow divider assembly fuel leakage, which could cause an engine fire, leading to an in-flight engine shutdown and forced landing.

Final rule; request for comments.

2001-12-07 General Electric Company: Amendment 39-12262. Docket No. 2001-NE-07-AD.

Applicability

This airworthiness directive (AD) is applicable to General Electric Company (GE) CT58-140-1, -140-2, and former military T58-GE-5, -8F, -10, -100, and -402 turboshaft engines, with fuel flow divider assemblies part numbers (P/N's) 4050T82G02, or 5040T77G02 having temperature control assemblies with serial numbers (SN's) with the first two digits of 95, 96, 97, 98, or 99 installed. These engines are installed on, but not limited to Agusta S.p.A. AS-6N, Boeing Vertol 107-11, Sikorsky S-61 Series and S-62 Series, 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): Carson S-61L, Firefly UH-1F, Glacier CH-3E, Quentin HH52A, Robinson Air Crane CH-3C, CH-3E, HH-3C, and HH-3E, Sikorsky S-61A, S-61D, S-61E, S-61V, and S-61V-1, and Siller Helicopters CH-3A, and SH-3A.Note 1: This AD applies to each engine identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For engines that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance

Compliance with this AD is required as indicated, unless already done.

To prevent fuel flow divider assembly fuel leakage, which could cause an engine fire, leading to an in-flight engine shutdown and forced landing, do the following within 120 hours time-in-service after the effective date of this AD:

(a) Locate the temperature control assembly, which is mounted on the fuel flow divider assembly and do the following:

(1) Read the temperature control assembly SN, located on the temperature control assembly end cap. The end cap can be identified by a one-inch hex flange and by being threaded into the fuel flow divider body.

(2) If the first two digits of the SN are 95, 96, 97, 98, or 99, or if the SN cannot be determined, replace the entire fuel flow divider assembly. Further information regarding SN location on the temperature control assembly may be found in GE Alert Service Bulletin CT58 73-A0080, dated February 13, 2001.

(b) After the effective date of this AD, do not install any fuel flow divider assembly P/N 4050T82G02 or 5040T77G02, that has the first two digits of the temperature control assembly SN of 95, 96, 97, 98, or 99.

Alternative Methods of Compliance

(c) An alternative method ofcompliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Engine Certification Office. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Engine Certification Office.

Note 2: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Engine Certification Office.

Special Flight Permits

(d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the aircraft to a location where the requirements of this AD can be accomplished.

Effective Date of this AD

(e) This amendment becomes effective on July 2, 2001.

On December 7, 2000, the FAA was made aware of three incidents of fuel leaking from the temperature control valve assembly, located on the fuel flow divider assembly. An investigation by GE revealed that the vendor of the temperature control valve assembly end caps did not accomplish the required manufacturing process steps following heat treatment. This has caused the end caps to be susceptible to intergranular corrosion which can result in cracking. This condition, if not corrected, could cause an engine fire, leading to an in-flight engine shutdown and forced landing.

Manufacturer's Service Information

The FAA has reviewed and approved the technical contents of GE Company Alert Service Bulletin (ASB) CT58 73-A0080, dated February 13, 2001, that describes procedures for locating suspect fuel flow divider assemblies, part numbers (P/N's) 4050T82G02 or 4067T04G02, then locating temperature control assemblies P/N's 5040T77G02 or 5040T87G02 by affectedserial number prefix, and then replacing fuel flow divider assemblies with serviceable parts.

FAA's Determination of an Unsafe Condition and Proposed Actions

Since an unsafe condition has been identified that is likely to exist or develop on other GE CT58 series turboshaft engines of the same type design, this AD is being issued to prevent fuel flow divider assembly fuel leakage, which could cause an engine fire, leading to an in-flight engine shutdown and forced landing. This AD requires locating suspect fuel flow divider assemblies by part number, then locating affected temperature control assemblies by part number and serial number prefix, and then replacing fuel flow divider assemblies with serviceable parts.

Immediate Adoption of This AD

Since a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days.

Comments Invited

Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications should identify the Rules Docket number and be submitted in triplicate to the address specified under the caption ADDRESSES. All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.

Comments are specifically invited on the overall regulatory, economic, environmental, andenergy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this action must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 2001-NE-07-AD." The postcard will be date stamped and returned to the commenter.

Regulatory Impact

This final rule does not have federalism implications, as defined in Executive Order 13132, because it 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. Accordingly, the FAA has not consulted with state authorities prior to publication of this final rule.

The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Safety.

Adoption of the Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Authority: 49 U.S.C. 106(g), 40113, 44701.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive: