Daily Rules, Proposed Rules, and Notices of the Federal Government
You may examine the AD docket on the Internet at
For service information identified in this proposed AD, contact American Eurocopter Corporation, 2701 Forum Drive, Grand Prairie, TX 75053-4005, telephone (800) 232-0323, fax (972) 641-3710, or at
We invite you to participate in this rulemaking by submitting written comments, data, or views. We also invite comments relating to the economic, environmental, energy, or federalism impacts that might result from adopting the proposals in this document. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. To ensure the docket does not contain duplicate comments, commenters should send only one copy of written comments, or if comments are filed electronically, commenters should submit only one time.
We will file in the docket all comments that we receive, as well as a report summarizing each substantive public contact with FAA personnel concerning this proposed rulemaking. Before acting on this proposal, we will consider all comments we receive on or before the closing date for comments. We will consider comments filed after the comment period has closed if it is possible to do so without incurring expense or delay. We may change this proposal in light of the comments we receive.
The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Community, has issued AD No. 2010-0100R1, dated August 4, 2010, and corrected August 11, 2010, to correct an unsafe condition for the specified Eurocopter model helicopters. EASA advises that a slow drift in the roll axis on the pilot's and co-pilot's attitude display screens occurred simultaneously during flight on several helicopters equipped with the GV76-1 vertical gyro unit installed in the rear cargo compartment. EASA advises “these drifts were caused by a fault in the vertical gyros unit installation in the rear cargo.” EASA states that in certain configurations, the GV76-1 vertical gyro unit installation has a natural mode close to the main rotor's harmonic frequency that generates rather significant vibratory levels on the GV76-1 unit by amplifying the intrinsic vibration of the aircraft. The faults are caused by these vibratory levels. EASA also states that the critical mode is essentially due to bending on the horizontal cross-members, which support the GV76-1 shelf.
These helicopters have been approved by the aviation authority of France and are approved for operation in the United States. Pursuant to our bilateral agreement with France, EASA, its technical representative, has notified us of the unsafe condition described in its AD. We are proposing this AD because we evaluated all known relevant information and determined that an unsafe condition is likely to exist or develop on other products of the same type design.
Eurocopter has issued an Alert Service Bulletin (ASB) No. 34.00.31 Revision 1, dated July 28, 2010 (ASB 34.00.31), for FAA type-certificated Model SA-365N1, AS-365N2, and AS365N3 helicopters and for military non-FAA type-certificated Model AS-365F, Fi, and K helicopters. ASB 34.00.31 specifies reinforcing the shelves of the vertical gyros GV76-1 (in cargo compartment) on the right hand (RH) or left-hand (LH) side. EASA classified this ASB as mandatory and issued AD No. 2010-0100R1, dated August 4, 2010, and corrected August 11, 2010, to ensure the continued airworthiness of these helicopters.
This proposed AD would require:
• Before further flight, revising the Limitations section of the Rotorcraft Flight Manual (RFM) to prohibit flight in instrument meteorological conditions (IMC) or night visual flight rules (VFR) for each helicopter with a vertical gyro unit GV76-1 installed on the rear cargo compartment shelf without reinforcement per Modification 365P081895.
• Within 110 hours time-in-service, modifying the GV76-1 vertical gyro unit shelf by complying with the Accomplishment Instructions, paragraphs 2.A. through 2.B.2.e. of the ASB. After reinforcing the shelf, operationally testing the GV76-1 vertical gyro unit and functionally test the navigation systems.
• Modifying the GV76-1 vertical gyro unit shelf is terminating action for the requirements of this AD.
• After modifying the GV76-1 vertical gyro unit shelf, removing this AD or deleting any changes to the Limitations section of the RFM that prohibit flight in IMC or VFR as a result of this AD.
We do not use the calendar dates, which have already passed. This AD prohibits flight in IMC or night VFR until MOD 365P081895 is accomplished.
We estimate that this proposed AD would affect 19 helicopters of U.S. registry. We also estimate that it would take about 16 work hours to install a
Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. 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.
We are issuing this rulemaking under the authority described in “Subtitle VII, Part A, Subpart III, Section 44701: General requirements.” Under that section, Congress charges the FAA 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 rulemaking action.
We 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.
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);
3. Will not affect intrastate aviation in Alaska to the extent that it justifies making a regulatory distinction; and
4. 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 proposed AD and placed it in the AD docket.
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows:
1. The authority citation for part 39 continues to read as follows:
49 U.S.C. 106(g), 40113, 44701.
2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):
This AD applies to Model SA-365N1, AS-365N2, and AS 365 N3 helicopters, with the GV76-1 vertical gyro unit installed on the left-hand (LH) or right-hand (RH) shelf in the rear cargo compartment, pre-MOD 365P081895, certificated in any category, all serial numbers except 6698, 6701, 6723, 6737, and 6741.
This AD defines the unsafe condition as an undetected flight display error of a slow drift in the roll axis. This condition could result in disorientation of the pilot and subsequent loss of control of the helicopter.
You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.
(1) Before further flight, revise the Limitations section of the Rotorcraft Flight Manual (RFM) by inserting a copy of this AD into the RFM or by pen and ink changes to the RFM that prohibits flight in instrument meteorological conditions (IMC) or night visual flight rules (VFR) for each helicopter with a vertical gyro unit GV76-1 installed on the rear cargo compartment shelf without reinforcement per Modification 365P081895.
(2) Within 110 hours time-in-service, modify the GV76-1 vertical gyro unit shelf as depicted in Figures 1 through 3 and by following the Accomplishment Instructions, paragraphs 2.A. through 2.B.2.e., of Eurocopter Alert Service Bulletin No. 34.00.31, Revision 1, dated July 28, 2010. After reinforcing the shelf, operationally test the GV76-1 vertical gyro unit and functionally test the navigation systems.
(3) After modifying the GV76-1 vertical gyro unit shelf, remove this AD from the Limitations section of the RFM or remove any changes to the Limitations section of the RFM that prohibit flight in IMC or VFR as a result of paragraph (d)(1) of this AD.
(4) Modifying the GV76-1 vertical gyro unit shelf is terminating action for the requirements of this AD.
(1) The Manager, Safety Management Group, FAA, may approve AMOCs for this AD. Send your proposal to: Mark F. Wiley, Aviation Safety Engineer, Rotorcraft Directorate, Regulations and Policy Group, 2601 Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5134; email
(2) For operations conducted under a 14 CFR part 119 operating certificate or under 14 CFR part 91, subpart K, we suggest that you notify your principal inspector, or lacking a principal inspector, the manager of the local flight standards district office or certificate holding district office before operating any aircraft complying with this AD through an AMOC.
(1) For service information identified in this AD, contact American Eurocopter Corporation, 2701 Forum Drive, Grand Prairie, TX 75053-4005, telephone (800) 232-0323, fax (972) 641-3710, or at
(2) The subject of this AD is addressed in European Aviation Safety Agency AD No. 2010-0100R1, dated August 4, 2010, and corrected August 11, 2010.
Joint Aircraft System/Component (JASC) Code: 3421: Attitude Gyro and Indicator System.