BOLETIN TÉCNICO DE SEGURIDAD OPERACIONAL AÉREA

Transcription

1 BOLETIN TÉCNICO DE SEGURIDAD OPERACIONAL AÉREA BT EUROCOPTER AS350B3 (ECUREUIL) HELICÓPTERO EUROCOPTER AS350B3 DIRIGIDO A: OPERADORES, ORGANIZACIONES DE MANTENIMIENTO APROBADAS, ESCUELAS TECNICAS DE AVIACIÓN, PILOTOS AVIADORES Y PERSONAL ADMINISTRATIVO DE TODAS LAS EMPRESAS DE AVIACIÓN QUE OPERAN EN EL PAIS EMITIDO: DEPARTAMENTO DE SEGURIDAD DE VUELO E INVESTIGACIÓN DE ACCIDENTES ASUNTO: ROTOR DE COLA, COJINETES ELASTOMÉRICOS DEL NÚCLEO DEL ROTOR DE COLA (TAIL ROTOR HUB) FECHA: 03 DE OCTUBRE DE 2012 De acuerdo a la información consignada en la nota de seguridad no S-64-Eurocopter, se ha evidenciado fuertes vibraciones originadas en el rotor de cola. Estas condiciones han mostrado daño propiamente en el rotor de cola, así como también en la caja de engranajes y en el estabilizador vertical, según el daño encontrado en los cojinetes laminados o elastoméricos, por lo que los mismos deberán ser reemplazados por cualquier deterioro detectado visualmente o por percibir vibración en el rotor de cola. Se sugiere la aplicación del Service Bulletin para el AS350 de fecha 19 de Septiembre de 2012 emitido por EUROCOPTER AN EADS COMPANY. SAFETY INFORMATION NOTICE NO.2507-S-64 SERVICE BULLETIN MJS

2 No S-64 SAFETY INFORMATION NOTICE SUBJECT: TAIL ROTOR Tail Rotor Hub - Laminated half-bearings For the attention of AIRCRAFT CONCERNED Civil Version(s) Military AS350 B3 AS550 C3 EUROCOPTER has been informed of an accident which occurred on September 28, 2012, involving an AS350 B3e helicopter (version B3 post MOD ). Before occurrence of the accident, the pilot felt strong vibrations originating from the tail rotor and reported them. The examination of the condition of the wreck shows the loss of the tail rotor including the TGB and the fin. Previously, all the laminated half-bearings of this aircraft had been replaced twice, after having logged few flying hours. Without predicting the results of the ongoing investigations, EUROCOPTER reminds you of the issue of Service Bulletin No for the AS350 and Service Bulletin No for the AS550, issued on September 19, The purpose of these Service Bulletins was to remind you of the inspection interval of these laminated half-bearings and to define a new, more efficient inspection method. Pending the results of the ongoing investigations, EUROCOPTER urges you to strictly comply with the instructions given in these documents and to inform the EUROCOPTER Technical Support in case of difficulty or questions concerning this subject. This Safety Information Notice supersedes SIN No S-64, issued on July 20, Tel.: +33 (0) Fax: +33 (0) DynComp.Technical-Support@eurocopter.com Revision Page 1/1

3 Civil version(s): B, BA, BB, D, B1, B2, B3 Military version(s): L1 SERVICE BULLETIN SUBJECT: TIME LIMITS - MAINTENANCE CHECKS For the attention of Inspection of the laminated half bearings ATA 05 and 64 Revision No. Date of issue Revision Summary: The purpose of this Service Bulletin is to enhance the visual inspection of the laminated half bearings. Compliance: This Service Bulletin is an amendment to Instructions for continued Airworthiness.. Revision Page 1/12

4 1. PLANNING INFORMATION 1.A. EFFECTIVITY 1.A.1. Helicopters/installed equipment On laminated half bearings P/N 704A (MPN ). 1.A.2. Non-installed equipment 1.B. ASSOCIATED REQUIREMENTS 1.C. REASON Premature cracks in laminated half bearings equipping Tail Rotor blades have recently been detected on several AS350 B3 helicopters Post MOD Because the laminated half bearing deteriorates progressively, EUROCOPTER has issued Safety Information Notice No S-64 to remind all operators of the particular attention that must be given during the visual check of the elastomeric part of the laminated half bearings during the ALF check. Deterioration of this part can generate in-flight vibrations, felt mainly in the pedals, requiring the pilot to land as soon as possible. In order to prevent the occurrence of in-flight vibrations, EUROCOPTER issues this Service Bulletin to enhance the laminated half bearing inspection procedure so as to detect any deterioration of the bearings as early as possible. EUROCOPTER is conducting all the necessary investigations with operators and the supplier of the laminated half bearings in order to identify the cause of the phenomenon. 1.D. DESCRIPTION - Visual inspection to make sure there is no deterioration of the laminated half bearings. - Interpretation of the results. Revision Page 2/12

5 1.E. COMPLIANCE 1.E.1. Compliance at the works 1.E.2. Compliance in service 1.E.2.a. Helicopters/installed equipment NOTE A change in the ALF maintenance interval (check after the last flight of the day) to 10H // 7D (P inspection, within 10 flying hours or 7 days, the first limit reached is applicable) is planned. 1.E.2.a.1. For helicopters equipped with additional Chinese weights (POST MOD ): Comply with paragraph 3. of this Service Bulletin at the latest after the last flight of the day (ALF) following receipt of this Service Bulletin, issued on the date indicated at the foot of the page. Then, Comply with paragraph 3. of this Service Bulletin after each last flight of the day (ALF), regardless of the interval indicated in the MSM. 1.E.2.a.2. For helicopters not equipped with additional Chinese weights (PRE MOD ): Comply with paragraph 3. of this Service Bulletin at the latest after the last flight of the day (ALF) following receipt of this Service Bulletin, issued on the date indicated at the foot of the page. Then, Comply with paragraph 3. of this Service Bulletin after each last flight of the day (ALF) or at each 10H // 7D inspection (P inspection) in accordance with the interval indicated in the MSM. 1.E.2.b. Non-installed equipment Revision Page 3/12

6 1.F. APPROVAL Approval of modifications: Approval of this document: The technical information contained in this Service Bulletin Revision 0 was approved on September 19, 2012 under the authority of EASA Design Organization Approval No. 21J.056 for helicopters of civil versions subject to an Airworthiness Certificate. The technical information contained in this Service Bulletin Revision 0 was approved on September 19, 2012 under the prerogatives of the recognition of design capability FRA21J-002-DGA for French Government helicopters. The technical information contained in this Service Bulletin Revision 0 was approved on September 19, 2012 by the EUROCOPTER Airworthiness Department for export military versions. 1.G. MANPOWER Qualification: For compliance with this Service Bulletin, EUROCOPTER recommends the following personnel qualifications: 1 Mechanical Aircraft Technician or 1 Pilot with the qualifications required to perform the inspections after the last flight of the day. Time for the operations: Visual inspection: 5 minutes. Estimated helicopter grounding time: 1.H. WEIGHT AND BALANCE 1.I. EFFECT ON ELECTRICAL LOADS 1.J. SOFTWARE MODIFICATION EMBODIMENT RECORD 1.K. REFERENCES The documents required for compliance with this Service Bulletin are as follows: AS350 B2 and B3: Tasks: ,4-3 (MMA), ,4-4 (MMA). AS350 BA, BB, B, D, L1, B1: Work Cards: , , (MRR). Revision Page 4/12

7 1.L. DOCUMENTS AFFECTED EUROCOPTER will modify the following documents with respect to this Service Bulletin: the MET and the MMA for AS350 helicopters - all versions, and the MSM only for AS350 helicopters equipped with additional Chinese weights (POST MOD ). The documents affected will be updated during a future revision. 1.M. INTERCHANGEABILITY OR MIXABILITY OF PARTS Interchangeability: Not applicable Mixability: Revision Page 5/12

8 2. MATERIAL INFORMATION 2.A. MATERIAL: PRICE - AVAILABILITY - PROCUREMENT 2.B. INFORMATION CONCERNING INDUSTRIAL SUPPORT 2.C. MATERIAL REQUIRED FOR EACH HELICOPTER/COMPONENT The products can be ordered separately from the INTERTURBINE AVIATION LOGISTICS company. Website: Telephone: AOG: D. MATERIAL TO BE RETURNED Revision Page 6/12

9 3. ACCOMPLISHMENT INSTRUCTIONS 3.A. GENERAL 3.B. OPERATIONAL PROCEDURE 3.B.1. Visual inspection of the laminated half bearings Pressure face: - Position both Tail Rotor blades horizontally. - Apply an axial perpendicular load (F) to one Tail Rotor blade (a) (See Figure 1). NOTE The load must be applied by hand to the pressure face of the blade, taking care not to reach the extreme position against the tail rotor hub. - While maintaining the load, visually inspect all the visible faces of the laminated half bearings (front faces and side faces) in area B of DETAIL A, in order to detect either of the following:. separation between the elastomer and the metal parts,. a crack in the elastomer,. extrusion (see example in Figure 4). NOTE A lamp can be used to enhance the inspection. - Interpret the results in accordance with paragraph 3.B.2. - Repeat the operation by applying the same load to the other blade in order to inspect the other laminated half bearing, then interpret the results in accordance with paragraph 3.B.2. Suction face: - Stand between the rotor and the tail boom. - Apply an axial perpendicular load (G) to one Tail Rotor blade (a), on the suction face side (See Figure 2). NOTE The load must be applied by hand to the suction face of the blade. - While maintaining the load, visually inspect area C in order to detect either of the following:. separation between the elastomer and the metal parts,. a crack in the elastomer,. extrusion (see example in Figure 4). NOTE A lamp can be used to enhance the inspection. - Interpret the results in accordance with paragraph 3.B.2. - Repeat the operation by applying the same load to the other blade in order to inspect the other laminated half bearing, then interpret the results in accordance with paragraph 3.B.2. Revision Page 7/12

10 3.B.2. Result analysis - If there is no separation, crack or extrusion, no maintenance is necessary. - If there is separation, a crack or extrusion, refer to the following criteria: Laminated bearings (Figure 3) Laminated area Permissible deterioration without repair Separation, crack: 1 anomaly permitted per half bearing with L = 5mm (.196 in.) max. OR P = 2mm (.078 in.) max. Colors (bright marks) None None Repair Deterioration requiring replacement If the deterioration is greater: - replace the deteriorated component ( ,4-3 and ,4-4) or ( or , ) Deterioration permitted. on the side faces Extrusion (Figure 4) None No deterioration permissible. - replace the deteriorated component ( ,4-3 and ,4-4) or ( or , ) or if in doubt, contact EUROCOPTER Support. 3.C. IDENTIFICATION Identification of this document: Record initial compliance with this document in the helicopter documents. 3.D. OPERATING AND MAINTENANCE INSTRUCTIONS Operating instructions: Maintenance instructions: 4. APPENDIX Revision Page 8/12

11 F F a A DETAIL A B B Figure 1 Revision Page 9/12

12 a G G. C Figure 2 Revision Page 10/12

13 Figure 3 Revision Page 11/12

14 Figure 4 - Example of extrusion Revision Page 12/12

15 No S-64 SAFETY INFORMATION NOTICE SUBJECT: TAIL ROTOR Tail Rotor Hub - Laminated half-bearings For the attention of AIRCRAFT CONCERNED Civil Version(s) Military AS350 B, BA, BB, B1, B2, B3, D L1 AS550 AS355 AS555 E, F, F1, F2, N, NP A2, C2, C3, U2 AF, AN, SN, UF, UN EUROCOPTER informs you of several reports of crack or failure of the elastomer of the laminated half-bearings of the tail rotor on AS350 B3e and AS355 NP helicopters. These deteriorations were observed during the scheduled checks of the laminated half-bearings of the tail rotor, sometimes on laminated bearings having logged very few flying hours. This occurrence, if not detected during maintenance, may over time cause vibrations in the Tail rotor, which may be felt through the pedals and lead the pilot to land as a precautionary measure. Without waiting for the results of the ongoing examinations on the laminated half-bearings concerned, EUROCOPTER reminds you that particular attention must be paid to the maintenance operations and especially to the visual check of the elastomer zone, in accordance with the documentation in force: - Check after the last flight of the day (ALF): Check of the general condition of the laminated half-bearings, visual examination to make sure that there is no separation, deep crack or emergence hour // 24 months (T) inspection. Revision Page 1/1