ALERT SERVICE BULLETIN

Full document text

T.F.S. No. 00000577 Approved under EASA DOA No. 21J.056. Page 1/11 2010.04.22 EUROCOPTER DIRECTION TECHNIQUE SUPPORT 13725 MARIGNANE CEDEX FRANCE EMERGENCY ALERT SERVICE BULLETIN COLIBRI Number VERSIONS Civil: B EC120 24A012 SUBJECT: ELECTRICAL POWER EMERgency SWitch (EMER SW) wiring REVISION No. DATE OF APPROVAL DATE OF ISSUE Revision 0 On: April 22, 2010 2010.04.22 This document is available on the internet: www.eurocopter.com/techpub T.F.S. No. 00000577 Approved under EASA DOA No. 21J.056. Page 2/11 2010.04.22 THE INFORMATION AND INSTRUCTIONS CONTAINED IN THIS ALERT SERVICE BULLETIN ARE INTENDED FOR MAINTENANCE PERSONNEL AND FLIGHT CREWS. 1. PLANNING INFORMATION 1.A. EFFECTIVITY 1.A.1. Helicopters/installed equipment Helicopters equipped with "EMER SW" switch with a Serial Number (S/N) listed below: - S/N 1500, - S/N between 1511 and 1630 (terminals included), - S/N 1632, 1634 and 1636. 1.A.2. On non-installed equipment Not applicable. 1.B. ASSOCIATED REQUIREMENTS Not applicable. 1.C. REASON Modification of the "EMER SW" switch wiring. This ALERT SERVICE BULLETIN will form the subject of an EASA Airworthiness Directive. 1.D. DESCRIPTION As part of a test conducted at EUROCOPTER, the "smoke in the cockpit" procedure was applied. It was found that setting the "EMER SW" switch to "CUT-OFF" (low position) and the "GENE" pushbutton to "OFF" at the same time, caused the aircraft starter-generator to cut-in again. The technical investigations conducted revealed that cross-wiring at the "EMER SW" switch caused the malfunction. In this configuration, the "smoke in the cockpit/cargo" procedure described in the flight manual does not isolate the equipment electrical power supply. Consequently, EUROCOPTER renders the embodiment of the modification described in this ALERT SERVICE BULLETIN, mandatory. CAUTION T.F.S. No. 00000577 Approved under EASA DOA No. 21J.056. Page 3/11 2010.04.22 1.E. COMPLIANCE EUROCOPTER renders compliance with this ALERT SERVICE BULLETIN mandatory. 1.E.1. Compliance at the works 1.E.1.a. On helicopters Not applicable. 1.E.1.b. On non-installed equipment Not applicable. 1.E.2. Compliance in service: By the operator 1.E.2.a. On helicopters/installed equipment - Comply with paragraph 2.B of this ALERT SERVICE BULLETIN within 15 flight hours, without exceeding 1 month, following receipt of this ALERT SERVICE BULLETIN, issued on the date indicated at the foot of the page. - Before the next flight following receipt of this ALERT SERVICE BULLETIN, inform the flight crews of the content of this ALERT SERVICE BULLETIN and draw their attention to the instruction below: Pending compliance with paragraph 2.B., in case of smoke in the cockpit with a source not identified, the flight crew must follow the appended procedure. 1.E.2.b. Non-installed equipment Not applicable. 1.F. APPROVAL 1.F.1. Approval of modifications The information or instructions related to FAM No. RFA 08090 approved on April 9, 2010 by EASA for civil version helicopters subject to an Airworthiness Certificate. 1.F.2. Approval of the Service Bulletin The technical information contained in this ALERT SERVICE BULLETIN Revision 0 was approved on April 22, 2010 under the authority of EASA Design Organisation Approval No. 21J.056 for civil version helicopters subject to an Airworthiness Certificate. T.F.S. No. 00000577 Approved under EASA DOA No. 21J.056. Page 4/11 2010.04.22 1.G. MANPOWER 1.G.1. Qualification - 1 electrical engineering technician (Modification to the wiring as per § 2.B.2.). - 1 pilot or 1 approved technician entitled to perform run-up.(Tests as per § 2.B.4.). 1.G.2. Time for the operations - Approximately 30 minutes (Modification to the wiring as per § 2.B.2.). - Approximately 30 minutes (Tests as per § 2.B.4.). 1.H. WEIGHT AND BALANCE Not applicable. 1.I. EFFECT ON ELECTRICAL LOADS Does not affect the helicopter electrical power breakdown. 1.J. SOFTWARE MODIFICATION EMBODIMENT RECORD Not applicable. 1.K. REFERENCES - Aircraft Maintenance Manual (AMM): AMM: Task 24-00-00,3-1. 1.L. OTHER DOCUMENTS AFFECTED The following documents will be issued subsequently: - Wiring Diagrams Manual (WDM). 1.M. TOOLING AFFECTED Not applicable. 1.N. INTERCHANGEABILITY OR MIXABILITY OF PARTS Not applicable. T.F.S. No. 00000577 Approved under EASA DOA No. 21J.056. Page 5/11 2010.04.22 2. ACCOMPLISHMENT INSTRUCTIONS 2.A. GENERAL - Read and comply with the general instructions concerning the electrical power supply as per AMM Task 24-00-00,3-1. 2.B. OPERATIONAL PROCEDURE 2.B.1. Preliminary steps - Remove the instrument panel vizor (a). 2.B.2. Wiring modification (Figures 1 and 2) - Using tool (zz), reconnect "EMER SW" (3PA) switch wires in compliance with Figure 2: . Wire marked "2431-0016" to terminal "3PA-1A". . Wire marked "2431-0003" to terminal "3PA-2A". 2.B.3. Final steps - Install the instrument panel vizor (a). 2.B.4. Tests To validate correct operation of the "EMER SW" switch, the following tests must be performed: - Set the helicopter into the following configuration: . [AVIONIC] (if installed) ON . [BAT/EPU] ON . [EMER SW] ON . Start-up the helicopter . [GENE] ON - Perform the following tests: . [EMER SW]: OFF Check that the equipment items are no longer energized, except: the engine, NR / NTL instrument and emergency lights (utility lights). . [BAT/EPU]: OFF Check that the equipment items are no longer energized, except: the engine, NR / NTL instrument and emergency lights (utility lights). . [GENE]: OFF Check that the equipment items are no longer energized, except: the engine, NR / NTL instrument and emergency lights (utility lights). . [EMER SW]: ON Check that the equipment items are no longer energized, except: the engine, NR / NTL instrument and emergency lights (utility lights). T.F.S. No. 00000577 Approved under EASA DOA No. 21J.056. Page 6/11 2010.04.22 . [BAT/EPU]: ON Check that all equipment items are energized. . [BAT/EPU]: OFF . [GENE]: ON