# AD 2000-20-19: Main Rotor Head - Type: Airworthiness directive - Status: Current - Products: Airbus Helicopters AS355E, AS355F, AS355F1, AS355F2, AS355N, AS350B, AS350B1, AS350B2, AS350B3, AS350BA, AS350C, AS350D and 1 more - Effective: November 20, 2000 - Published: October 16, 2000, 65 FR 61085–61087 - Issued: September 29, 2000 - Issued as: Final rule - Supersedes: [AD 86-15-10 R2](https://openairdocs.org/ad/86-15-10-R2) - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Rotorcraft - Amendment: 39-11931 - Docket: 2000-SW-25-AD - Registered aircraft: 951 may be affected, by airframe or engine model (OpenAirDocs) - Official PDF: https://openairdocs.org/files/sha256/b1/49/b149d487e40a25a7e1572e4fc81e12ee272250f87cbd8cf633eca2bfc904f7a8 (from https://www.govinfo.gov/content/pkg/FR-2000-10-16/pdf/00-26234.pdf) - Federal Register: https://www.federalregister.gov/documents/2000/10/16/00-26234/airworthiness-directives-eurocopter-france-model-as-350b-ba-b1-b2-b3-c-d-and-d1-and-as-355e-f-f1-f2 - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/4131FA8EF632D4E686256A4F00418D5C.0001 - DRS record last changed: November 21, 2025 - Page: https://openairdocs.org/ad/2000-20-19 ## Summary This amendment supersedes an existing airworthiness directive (AD) for Eurocopter France Model AS-350B, BA, B1, B2, C, D, and D1, and AS-355E, F, F1, and F2 helicopters. That AD currently requires inspections of the main rotor head components, the main gearbox (MGB) suspension bars, and the ground resonance prevention system components. This amendment requires those same inspections, but would also apply to Model AS-350B3 and AS-355N helicopters. This amendment is prompted by the inadvertent omission of those model helicopters from the previous AD. The actions specified by this AD are intended to prevent ground resonance due to reduced structural stiffness, which could lead to failure of a main rotor head or MGB suspension component and subsequent loss of control of the helicopter. ## The airworthiness directive ### 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: 1. The authority citation for part 39 continues to read as follows: 2. Section 39.13 is amended by removing Amendment 39-11681 (65 FR 20721, April 18, 2000), Amendment 39-6515 (55 FR 5833, February 20, 1990) and Amendment 39-5517 (52 FR 13233, April 22, 1987) and by adding a new airworthiness directive (AD), Amendment 39-11931, to read as follows: 2000-20-19 Eurocopter France: Amendment 39-11931. Docket No. 2000-SW-25-AD. Supersedes AD 86-15-10 R2, Amendment 39-11681, Docket No. 98-SW-82-AD; AD 86-15-10R1, Amendment 39-6515, Docket No. 86-ASW-22; and AD 86-15-10, Amendment 39-5517, Docket No. 86-ASW-22. Applicability: Model AS-350B, BA, B1, B2, B3, C, D, and D1, and AS-355E, F, F1, F2 and N helicopters, certificated in any category. Note 1: This AD applies to each helicopter identified in the preceding applicability provision, regardless of whether it has been otherwise modified, altered, or repaired in the area subject to the requirements of this AD. For helicopters 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 (f) 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: Required as indicated, unless accomplished previously. To prevent ground resonance due to reduced structural stiffness, which could lead to failure of a main rotor head or main gearbox (MGB) suspension component and subsequent loss of control of the helicopter, accomplish the following: (a) Within 10 hours time-in-service (TIS): (1) For Model AS-350B, BA, B1, B2, B3, C, D, and D1 helicopters, inspect the main rotor head components, the MGB suspension bars (struts), and the landing gear ground resonance prevention components (aft spring blades and hydraulic shock absorbers) in accordance with paragraph CC.3 of Aerospatiale Service Bulletin (SB) No. 01.17a (not dated). (2) For Model AS-355E, F, F1, F2, and N helicopters, inspect the main rotor head components, the MGB suspension bars (struts), and the landing gear ground resonance prevention components (aft spring blades and hydraulic shock absorbers) in accordance with paragraph CC.3 of SB No. 01.14a (not dated). (b) Rework or replace damaged components in accordance with SB No. 01.17a or SB No. 01.14a, as applicable. (c) Repeat the inspections and rework required by paragraphs (a) and (b) of this AD at intervals not to exceed 500 hours TIS. (d) If the helicopter is subjected to a hard landing or to high surface winds when parked without effective tiedown straps installed, repeat the inspections required by paragraph (a) of this AD for the main rotor head star arms and the MGB suspension bars (struts) before further flight. (e) After a landing with abnormal self-sustained dynamic vibrations (ground resonance type vibrations), repeat all the inspections required by paragraph (a) of this AD. (f) 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, Regulations Group, Rotorcraft Directorate, FAA. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Regulations Group. Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Regulations Group. (g) 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 helicopter to a location where the requirements of this AD can be accomplished. (h) The inspections shall be done in accordance with paragraph CC.3 of Aerospatiale Service Bulletin No. 01.17a (not dated) or No. 01.14a (not dated), as applicable. The rework or replacement, if necessary, shall be done in accordance with Aerospatiale Service Bulletin No. 01.17a or No. 01.14a (neither is dated), as applicable. The incorporation by reference of those documents was previously approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51 as of May 23, 2000 (65 FR 20721, April 18, 2000). Copies may be obtained from American Eurocopter Corporation, 2701 Forum Drive, Grand Prairie, Texas 75053-4005, telephone (972) 641-3460, fax (972) 641-3527. Copies may be inspected at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (i) This amendment becomes effective on November 20, 2000. ## Rule preamble ### Dates Effective November 20, 2000. The incorporation by reference of certain publications listed in the regulations was approved previously by the Director of the Federal Register as of May 23, 2000 (65 FR 20721, April 18, 2000). ### Addresses The service information referenced in this AD may be obtained from American Eurocopter Corporation, 2701 Forum Drive, Grand Prairie, Texas 75053-4005, telephone (972) 641-3460, fax (972) 641-3527. This information may be examined at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. ### For further information contact Jim Grigg, Aviation Safety Engineer, FAA, Rotorcraft Directorate, Rotorcraft Standards Staff, 2601 Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5490, fax (817) 222-5961. ### SUPPLEMENTARY INFORMATION A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 86-15-10 R2, Amendment 39-11681 (65 FR 20721), which applies to Eurocopter France Model AS-350B, BA, B1, B2, B3, C, D, and D1, and AS-355E, F, F1, F2 and N helicopters was published in the Federal Register on July 20, 2000 (65 FR 44995). That action proposed to require an initial inspection within 10 hours time-in-service (TIS) and thereafter, repetitive inspections of the main rotor head components, the MGB suspension bars, and the ground resonance prevention system components at intervals not to exceed 500 hours TIS. Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposal or the FAA's determination of the cost to the public. The FAA has determined that air safety and the public interest require the adoption of the rule as proposed. The FAA estimates that 586 helicopters of U.S. registry will be affected by this AD, that it will take approximately 8 work hours per helicopter to accomplish the required actions, and that the average labor rate is $60 per work hour. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $480 per helicopter, or $281,280 for the entire fleet. 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. For the reasons discussed above, I certify that this action (1) is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under 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. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption ADDRESSES. ## Affected data sheets (2) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS H9EU](https://openairdocs.org/tcds/H9EU): Airbus Helicopters; names 8 of 10 models: AS350C, AS350B3, AS350B, AS350D1, AS350B2, AS350B1, AS350D, AS350BA - [TCDS H11EU](https://openairdocs.org/tcds/H11EU): Airbus Helicopters; names 5 of 6 models: AS355N, AS355F2, AS355F1, AS355E, AS355F ## Registered aircraft it may apply to (OpenAirDocs) Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment. - Aircraft: 951 (951 by airframe model, 0 by engine model) - Makers: Airbus Helicopters 362, Eurocopter 328, American Eurocopter 162, Aerospatiale 66, Eurocopter France 20, S N I A S 8, Eurocopter/France 4, Airbus Helicopter 1 Models with the most aircraft: - [Airbus Helicopters AS350B3](https://openairdocs.org/model/airbus-helicopters-as350b3): 291 aircraft (airframe model) - [Eurocopter AS 350 B3](https://openairdocs.org/model/eurocopter-as-350-b3): 167 aircraft (airframe model) - [Eurocopter AS 350 B2](https://openairdocs.org/model/eurocopter-as-350-b2): 146 aircraft (airframe model) - [American Eurocopter AS350B3](https://openairdocs.org/model/american-eurocopter-as350b3): 124 aircraft (airframe model) - [Airbus Helicopters AS 350B3](https://openairdocs.org/model/airbus-helicopters-as-350b3): 56 aircraft (airframe model) - [American Eurocopter AS350B2](https://openairdocs.org/model/american-eurocopter-as350b2): 38 aircraft (airframe model) - [Aerospatiale AS350BA](https://openairdocs.org/model/aerospatiale-as350ba): 18 aircraft (airframe model) - [Aerospatiale AS350B](https://openairdocs.org/model/aerospatiale-as350b): 13 aircraft (airframe model) - [Eurocopter AS 350 BA](https://openairdocs.org/model/eurocopter-as-350-ba): 13 aircraft (airframe model) - [Aerospatiale AS350B2](https://openairdocs.org/model/aerospatiale-as350b2): 11 aircraft (airframe model) - [Airbus Helicopters AS350B2](https://openairdocs.org/model/airbus-helicopters-as350b2): 10 aircraft (airframe model) - [Aerospatiale AS 355F1](https://openairdocs.org/model/aerospatiale-as-355f1): 9 aircraft (airframe model) - [Eurocopter France AS 350 B3](https://openairdocs.org/model/eurocopter-france-as-350-b3): 8 aircraft (airframe model) - [Eurocopter France AS350B2](https://openairdocs.org/model/eurocopter-france-as350b2): 8 aircraft (airframe model) - [Aerospatiale AS 355F2](https://openairdocs.org/model/aerospatiale-as-355f2): 6 aircraft (airframe model) - [S N I A S AS-350B ECUREUIL](https://openairdocs.org/model/s-n-i-a-s-as-350b-ecureuil): 5 aircraft (airframe model) - [Eurocopter/France AS355N TWINSTAR](https://openairdocs.org/model/eurocopter-france-as355n-twinstar): 4 aircraft (airframe model) - [Aerospatiale AS355F2 ECUREUIL](https://openairdocs.org/model/aerospatiale-as355f2-ecureuil): 3 aircraft (airframe model) - [Airbus Helicopters AS350BA](https://openairdocs.org/model/airbus-helicopters-as350ba): 2 aircraft (airframe model) - [Airbus Helicopters AS355N](https://openairdocs.org/model/airbus-helicopters-as355n): 2 aircraft (airframe model) All 36 models: https://openairdocs.org/ad/2000-20-19/models.md Every aircraft: https://openairdocs.org/ad/2000-20-19/aircraft.md ## Related documents - [AD 86-15-10 R2](https://openairdocs.org/ad/86-15-10-R2) (historical): Main Rotor Head Components, the Main Gearbox (MGB) Suspension Bars, and Ground Resonance Prevention System Components · Eurocopter France AS-350B, AS-350B1, AS-350B2 and 8 more. Effective May 23, 2000. Replaced by this AD - [Proposed rule 2000-SW-25-AD](https://openairdocs.org/proposed/2000-SW-25-AD): Notice of proposed rulemaking (NPRM), published Jul 20, 2000 Its text cites no advisory circulars or STCs. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.