This amendment adopts a new AD for Eurocopter Model EC 155B, EC155B1, SA-360C, SA-365C, SA-365C1, SA- 365C2, SA-365N, SA-365N1, AS-365N2, AS 365 N3, and SA-366G1. This action requires an initial and repetitive borescope inspection of the MGB planet gear carrier or an initial and repetitive visual inspection of the MGB planet gear carrier for a crack. Replacing any MGB that has a cracked planet gear carrier is required before further flight. This amendment is prompted by the discovery of cracks in the web of the planet gear carrier. This condition, if not detected and corrected, could lead to a MGB seizure and subsequent loss of control of the helicopter.
This AD is an interim action; the manufacturer and the FAA are continuing to collect information concerning the formation of these cracks. We will consider further rulemaking once we determine the cause of these cracks.
The Direction Generale de L'Aviation Civile (DGAC), the airworthiness authorityfor France, notified the FAA that an unsafe condition may exist on Eurocopter Model EC 155B, EC155B1, SA 365 N and N1, AS 365 N2 and N3, SA 366 G1, SA 365 C, C1, C2, and C3, SA 360 helicopters. The DGAC advises of cases of cracks that were discovered in the web of the planet gear carrier of the MGB. The DGAC advises that rupture of the web of the planet gear carrier can lead to seizure of the MGB.
Eurocopter has issued Alert Telex Nos. 05.00.48, 05.33, 05.26, and 05A007, dated December 16, 2004. The alert telex specifies performing periodic borescope inspections of the MGB planet gear carrier at regular intervals to make sure that there is no crack in the web. The manufacturer states that a periodic borescope inspection is mandatory, so that a crack, if any, can be detected before it generates any chips which can be found on the magnetic plug. The DGAC classified this alert telex as mandatory and issued AD UF-2004-194, effective December 17, 2004, 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.
This unsafe condition is likely to exist or develop on other helicopters of the same type designs. Therefore, this AD is being issued to detect a crack in the web of the planet gear carrier, which could lead to a MGB seizure and subsequent loss of control of the helicopter. This AD requires the following:
For a MGB that has less than 250 hours time-in-service (TIS) since new or last overhaul, borescope inspecting or visually inspecting the web of the planet gear carrier for a crack. The inspections must be done on or before the MGB reaches 265 hours TIS and then at intervals not to exceed 50 hours TIS.
For a MGB that has 250 or more hours TIS since new or since last overhaul, borescope inspecting or visually inspecting the web of the planet gear carrier for a crack. The inspections must be done within 15 hours TIS and then at intervals not to exceed 50 hours TIS.
For any MGB that has a cracked planet gear carrier, replacing the MGB with an airworthy MGB before further flight.
The inspections shall be done using the Alert Telex described previously. The short compliance time involved is required because the previously described critical unsafe condition can adversely affect the structural integrity and controllability of the helicopter. Fifty hours TIS equates to approximately 30 days of operations for these model helicopters. Therefore, because of the short compliance time, this AD must be issued immediately.
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.
We estimate that this AD will affect 145 helicopters. Each borescope inspection will take approximately 1 work hour and each visual inspection will take approximately 12 hours. Replacing the MGB, if necessary, will take approximately 16 work hours. The average labor rate is $65 per work hour. Required parts will cost approximately $68,780 per main gearbox. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $3,534,280, assuming that a borescope inspection is done on the entire fleet 12 times a year, that no visual inspection is done, and that 49 MGBs are replaced.
Comments Invited
This AD is a final rule that involves requirements that affect flightsafety and was not preceded by notice and an opportunity for public comment; however, we invite you to submit any written data, views, or arguments regarding this AD. Send or deliver your comments to an address listed under ADDRESSES. Include ``Docket No. FAA-2005-20294; Directorate Identifier 2004-SW-39-AD'' at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the AD. We will consider all comments received by the closing date and may amend the AD in light of those comments.
We will post all comments we receive, without change, to http://dms.dot.gov , including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this AD. Using the search function of our docket Web site, you can find and read the comments to any of our dockets, including the name of the individual who sent the comment. 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://dms.dot.gov .
Regulatory Findings
We have determined that this AD will not have federalism implications under Executive Order 13132. This AD 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.
For the reasons discussed above, I certify that the 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. Will 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 an economic evaluation of the estimated costs to comply with this AD. See the DMS to examine the economic evaluation.
Authority for This Rulemaking
The FAA's authority to issue rules regarding aviation safety is found in Title 49 of the United States Code. 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.
This rulemaking is promulgated under the authority described in subtitle VII, part A, subpart III, section 44701, ``General requirements.'' Under that section, the FAA is charged 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 AD.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, 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 a new airworthiness directive to read as follows: