## EASA EMERGENCY AIRWORTHINESS DIRECTIVE

AD No: 2007- 0141-E

Date: 21 May 2007

No person may operate an aircraft to which an Airworthiness Directive applies, except in accordance with the requirements of that Airworthiness Directive unless otherwise agreed with the Authority of the State of Registry. 

### Type Approval Holder’s Name:

EUROCOPTER Type/Model designation(s):

AS 350 and AS 355

TCDS Number: EASA.R.008 & EASA.R.146

Foreign AD: Not applicable.

Supersedure: Not applicable



### ATA 67 Rotor Flight Controls - Main & Tail Rotors Servo-Controls - Inspection / Replacement.

Manufacturer(s): EUROCOPTER – (forme rly EUROCOPTER-FRANCE, AEROSPATIALE)

Applicability: EUROCOPTER helicopters models: - AS 350 B, BA, BB, B1, B2, B3 and D - AS 355 E, F, F1, F2 and N, all serial numbers, and equipped with GOODRICH main rotor servo-controls and tail rotor servo-controls with no letter “C” marked in the inspection box of the servo-control identification plate, and with the following Part Numbers (P/N) and Serial Numbers (S/N): - Main rotor servo-controls P/N SC5083 with S/N 270M, 272M, 409M, 423M, 452M or 1573 P/N SC5083-1 with S/N from 2902 to 2921 inclusive P/N SC5084 with S/N 30, 84, 104, 186, 438, 575 or 695 P/N SC5084-1 with S/N from 1462 to 1481 inclusive

. And - Tail rotor servo-controls: P/N SC5072 with serial number 222M, 306M or 309.

Reason: An internal review revealed that some main and tail rotor servo-controls do not conform to the approved design. This results in a greater play in the input lever bearing which could lead to off-centered lever/distributor slide valve. If not corrected, this condition could jam the distributor slide valve in its sleeve contributing to reduced controllability of the rotors. Such a jamming would be detected during the pre-flight hydraulic check by a “hard point” in the flight controls. This Airworthiness Directive requires identification of the affected main and tail rotor servo-controls and mandates additional attention during the pre flight check and subsequent replacement.Effective Date: 23 May 2007

Compliance: 1. Before further flight, verify the Part Number (P/N) and Serial Number (S/N) of the main rotor and tail rotor servo-controls in accordance with paragraph (§) 1.E.2. of EUROCOPTER Alert Service Bulletin (ASB) No. 01.00.58 Revision 1 for AS 350 helicopters and ASB No. 01.00.53 Revision 1 for AS 355 Helicopters

Note 1 : Instead of inspecting the rotorcraft, a review of the helicopter maintenance records along with any other applicable data (rotorcraft logbook, Components list, etc...) is acceptable if each P/N and S/N can be positively determined from that review.

2. When a servo-control whose P/N and S/N are listed in the applicability section of this AD, is identified:

2.1 During each pre-flight test (see Rotorcraft Flight Manual section 4) and until accomplishment of § 2.2 of this AD, Check thoroughly that no “hard point” exists in the flight controls.

If any “hard point” is detected in the flight controls, Prior to next flight replace the defective servo-control(s) as instructed in § 2.B. of EUROCOPTER ASB No. 01.00.58 Revision 1 for AS 350 helicopters and ASB No. 01.00.53 Revision 1 for AS 355 Helicopters.

2.2 Within the next 50 Flight Hours or 4 months after the effective date of this AD, whichever occurs first, replace all servo-controls that are identified in the Applicability Section of this AD, as instructed in § 2.B. of EUROCOPTER ASB No. 01.00.58 Revision 1 for AS 350 helicopters and ASB No. 01.00.53 Revision 1 for AS 355 Helicopters

3. As of the effective date of this AD , no person shall install rotors servocontrols whose P/N and S/N are listed in the applicability section of this AD, on any EUROCOPTER AS 350 and AS 355 helicopters unless they have been previously returned to conformity by the equipment manufacturer as indicated in § 2. of EUROCOPTER ASB No. 01.00.58 Revision 1 for AS 350 helicopters and ASB No. 01.00.53 Revision 1 for AS 355 Helicopters

Ref. Publications: EUROCOPTER AS 350 Alert Service Bulletin No. 01.00.58 Revision 1 EUROCOPTER AS 355 Alert Service Bulletin No. 01.00.53 Revision 1 or any subsequent approved revision.

Remarks: 1. If requested and appropriately substantiated the responsible EASA manager for the related product has the authority to accept Alternative Methods of Compliance (AMOCs) for this AD.
2. The safety assessment has requested not to implement the full consultation process and an immediate publication and notification.
3. Enquiries regarding this Airworthiness Directive should be referred to the

AD Focal Point - Certification Directorate, EASA. E-mail: ADs@easa.europa.eu

. 4. For any question concerning the technical content of the requirements in this AD, please contact: EUROCOPTER (STDI) - Aéroport de Marseille Provence 13725 Marignane Cedex - France. Tel: 33 (0) 4 42 85 97 97 - Fax: 33 (0) 4 42 85 99 66.

E-mail: Directive.technical-support@eurocopter.com