AD 2001-26-06

This amendment adopts a new airworthiness directive (AD) that is applicable to CFE Company model CFE738-1-1B turbofan engines. This action requires the removal of certain fan rotor disks from service. This amendment is prompted by a report from a forging manufacturer, of a metallurgical inclusion (contaminant) found in a forging made from a certain ingot of titanium. Fan rotor disks for model CFE738-1-1B engines have been manufactured from this same ingot and are suspect for metallurgical inclusions. The actions specified in this AD are intended to remove from service affected fan rotor disks, which if not removed, could result in uncontained engine failure and damage to the airplane.

Final rule; request for comments.

2001-26-06 CFE Company: Amendment 39-12570. Docket 2001-NE-28-AD.

Applicability: This airworthiness directive (AD) is applicable to CFE Company model CFE738-1-1B turbofan engines that contain fan rotor disks part number (P/N) 3050745-2, serial numbers (SN's) 000322903511 through 000322903536, and 000322903538 through 000322903541. These engines are installed on, but not limited to Dassault Aviation Falcon 2000 series airplanes.

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 (g) 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 remove from service affected fan disks, which if not removed, could result in uncontained engine failure and damage to the airplane, do the following:

(a) Remove from service before further flight, the following serial number (SN) fan rotor disks listed in Table 1:

Table 1. SN's of Fan Rotor Disks Requiring Removal Before Further Flight

000322903512
000322903513
000322903516
000322903517
000322903518
000322903519
000322903520
000322903521
000322903523
000322903524
000322903525
000322903527
000322903528
000322903529
000322903530
000322903531
000322903533
000322903534
000322903535
000322903536
000322903538
000322903539
000322903540
000322903541

(b) Remove from service within 10 engine cycles-in-service after the effective date of this AD, fan rotor disks SN's 000322903511, 000322903515, and 000322903526.

(c) Remove from service within 70 engine cycles-since-new (CSN), fan rotor disk SN 000322903514.

(d) Remove from service within 140 engine CSN, fan rotor disks SN 000322903522 and 000322903532.

(e) The manufacturer's records indicate that fan rotor disks identified in paragraphs (a) through (d) of this AD were installed in, and may still be installed in the engines listed by SN in the following Table 2. This AD, however, applies to any engine with the fan rotor disks installed, identified in paragraphs (a) through (d) of this AD. Table 2 is provided for informational purposes only to assist in locating engines that may be affected. For information on replacing the affected fan rotor disks in this AD, see CFE Company Alert Service Bulletin CFE738-A72-8053, dated July 24, 2001.

105430
105432105434
105438
105441
105443
105444
105445
105446
105447
105448
105450
105451
105452
105453
105454
105455
105456
105457
105459
105461
105462
105463
105466
105467
105469
105471
105472
105474
105475

(f) After the effective date of this AD, do not install any fan rotor disks P/N 3050745-2, SN's 000322903511 through 000322903536, and 000322903538 through 000322903541 onto any engine.

Alternative Methods of Compliance

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

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

Special Flight Permits

(h) Special flight permits may be issued in accordance with Secs. 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 done.

Effective Date

(i) This amendment becomes effective on January 7, 2002.

The FAA was recently notified of a report from a forging manufacturer of a metallurgical inclusion (contaminant) found by ultrasonic inspection in a certain forged part. This part was made from a certain ingot of titanium. The engine manufacturer also reports that CFE738 fan rotor disks were manufactured from this same ingot and are, therefore, suspected of containing these metallurgical inclusions. Metallurgical inclusions are known to be crack initiation sites in highly stressed engines parts. Cracks that have initiated from inclusions in disk material have caused uncontained disk failures. The FAA has therefore determined that these suspect fan rotor disks could fail as a result of having metallurgical inclusions. This condition, if not corrected, could result in uncontained engine failure and damage to the airplane.

Requirements of This AD

Since an unsafe condition has been identified that is likely to exist or develop on other CFE Company modelCFE738-1-1B turbofan engines of the same type design, this AD is being issued to remove from service affected fan rotor disks, which if not removed, could result in uncontained engine failure and damage to the airplane. This AD requires the removal from service of certain fan rotor disks, either before further flight or by an engine cycle schedule, based on fan rotor disk serial number.

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, and energy 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 RulesDocket.

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-28-AD." The postcard will be date stamped and returned to the commenter.

Regulatory Analysis

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: