On January 8, 2004, the FAA issued Emergency AD 2004-01-51 for the specified model helicopters with less than 10 hours TIS since installing a main or combiner gearbox received from the Eurocopter Marignane, France, works. The emergency AD requires, before further flight, replacing any of these affected gearboxes with appropriate airworthy gearboxes received from another source. This is an interim action pending the results of an ongoing investigation. That action was prompted by a report of a main gearbox free-wheel unit slipping, resulting in an engine overspeed and shut-down, which occurred during the single-engine phase of an acceptance flight. This condition, if not corrected, could result in an engine overspeed, an engine shut-down, and subsequent loss of control of the helicopter.
The FAA has reviewed Eurocopter Alert Telex No. 63.00.21 R1, dated December 19, 2003, which describes procedures for contacting the manufacturer and cleaning the bevel reduction gear pending the results of an ongoing investigation.
The Direction Generale De L'Aviation Civile (DGAC), the airworthiness authority for France, notified the FAA that an unsafe condition may exist on these helicopter models. The DGAC advises of a main gearbox free-wheel slippage with resulting engine shut-down due to overspeed, which occurred during the single-engine phase of an acceptance flight at the Eurocopter works. The DGAC classified the Alert Telex as mandatory and issued AD No. UF-2003-454, dated December 11, 2003, to ensure the continued airworthiness of these helicopters in France.
These helicopter models are manufactured in France and are type certificated for operation in the United States under the provisions of 14 CFR 21.29 and the applicable bilateral agreement. Pursuant to the applicable bilateral agreement, the DGAC has kept the FAA informed of the situation described above. The FAA has examined the findings of the DGAC, reviewed all available information, and determined that AD action is necessary for products of these type designs that are certificated for operation in the United States.
Since the unsafe condition described is likely to exist or develop on other Eurocopter helicopters of the same type design, the FAA issued Emergency AD 2004-01-51 to prevent an engine overspeed, an engine shut- down, and subsequent loss of control of the helicopter. This AD requires, before further flight, for helicopters with less than 10 hours TIS since installing a main or a combiner gearbox received from Eurocopter, Marignane, France, works, replacing the gearbox with an appropriate airworthy gearbox received from another source. The short compliance time involved is required because the previously described critical unsafe condition can adversely affect the controllability of the helicopter. Therefore, replacing any affected gearbox with an appropriate airworthy gearbox is required before further flight, and this AD must be issued immediately.
Since it was found that immediate corrective action was required, notice and opportunity for prior public comment thereon were impracticable and contrary to the public interest, and good cause existed to make the AD effective immediately by individual letters issued on January 8, 2004, to all known U.S. owners and operators of Eurocopter Model AS355E, F, F1, F2, and N helicopters. These conditions still exist, and the AD is hereby published in the Federal Register as an amendment to 14 CFR 39.13 to make it effective to all persons.
The FAA estimates that this AD will affect 104 helicopters of U.S. registry and will take approximately 1/2 work hour to determine applicability and 12 work hours to replace a gearbox at an average labor rate of $65 per work hour. Required parts will cost approximately $97,000 per helicopter. Based on these figures, we estimate the total cost impact of the AD on U.S. operators to be $981,180, assuming 10 gearboxes are replaced.
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 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 mailed comments submitted in response to this rule must submit a self- addressed, stamped postcard on which the following statement is made: "Comments to Docket No. 2003-SW-56-AD." The postcard will be date stamped and returned to the commenter.
The regulations adopted herein will 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. Therefore, it is determined that this final rule does not have federalism implications under Executive Order 13132.
The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and that it 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.
39.13 [Amended]
2. Section 39.13 is amended by adding a new airworthiness directive to read as follows: