ALERT SERVICE BULLETIN BO105

EASA.21J.034. 1.F. Manpower Requirement For check of the wire terminals i.a.w. Section 2.A.: approx. 2 man--hours For retrofit of a ground reference line: approx. 12 man--hours April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 3 of 18 1.G. Material, Cost and Availability Cost and availablity of required retrofit kits will be provided by ECD, Dept. Spares Order Administration. 1.H. Special Tools (Not applicable) 1.I. Mass and Moment If wire harness is retrofitted Mass 0.175 kg Moment 455 kgmm 1.J. Reference MM BO105 1.K. Other Publications affected This Alert Service Bulletin will be incorporated in the Wiring Diagram Manual WDM BO105 with one of the next revisions. 1.L. Electrical Load Data (Not applicable) 2. ACCOMPLISHMENT INSTRUCTIONS 2.A. Inspections Required 2.A.1. Visual inspection of grounding connection on starter--generator: NOTE The grounding connection on the starter--generator is identical for the RH and the LH side. Thus the accomplishment of the visual inspection is identical for the LH and RH side. 2.A.1.1. Disconnect battery and, if connected, the external power supply from the helicopter electrical system. 2.A.1.2. Remove engine cowling i.a.w. maintenance manual MBB-BO105, Section 22. 2.A.1.3. Using a torch and a mirror, inspect for damage, corrosion and cracks on wire terminal of wire P55F16N / P56F16N on terminal E of starter--generator. 2.A.1.4. If damage is found or suspected, the wire terminal must be replaced as follows: -- Remove nut from terminal E of the starter--generator and store for reuse. April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 4 of 18 -- Remove wire terminal of the thin wire from terminal E. Cut off wire at the wire terminal. -- Strip wire and crimp on new wire terminal (1, Figure 1). -- Attach wire terminal to terminal E of the starter--generator using a nut. Torque--tighten nut to 25--26.5 Nm. Ensure that the wire terminal is centrically aligned and that the wire is installed without tension when the nut is tightened. -- Perform functional test i.a.w. MM, MBB-BO105, Kapitel 92-17. 2.A.2. Measurement of resistance between starter--generator and generator voltage regulator: NOTE The generator voltage regulator on the LH side is identical to the generator voltage regulator on the RH side. Thus the procedure for resistance measurement is identical for the LH and RH side. 2.A.2.1. Provide access to the electrical master box 1VE i.a.w. MM, MBB-BO105, chapter 92-22. 2.A.2.2. Disconnect plug from generator voltage regulator. 2.A.2.3. Measure the resistance using an ohmmeter. Preselect measuring mode “resistance” and a suitable measuring range. Connect one probe of the ohmmeter to terminal E of the starter--generator and the other probe i.a.w. the following list: Model Plug Contact BO105 excluding model D 104Pa / 204Pa G BO105 model D 108Pa / 208Pa F 2.A.2.4. The resistance reading must be 0.5 ohms or less. 2.A.2.5. Install engine cowling i.a.w. maintenance manual MBB--BO105, chapter 92-22. 2.A.2.6. Confirm accomplishment of this Alert Service Bulletin by an entry in the historical record of the helicopter. 2.B. Work Procedure EFFECTIVITY All affected helicopters up to S/N 0160 2.B.1. Check, whether the ground reference line is not connected to the starter--generator: 2.B.1.1. Remove engine cowling i.a.w. MM, MBB-BO105, Chapter 22. 2.B.1.2. Remove nut from terminal E of the starter--generator and store for reuse. 2.B.1.3. Disconnect all wires with their wire terminals from terminal E and position them so that the individual wire terminals are not electrically connected to each other. April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 5 of 18 NOTE The generator voltage regulator on the LH side is identical to the generator voltage regulator on the RH side. Thus the procedure for resistance measurement is identical for the LH and RH side. 2.B.1.4. Provide access to the electrical master box 1VE i.a.w. MM, MBB-BO105, chapter 92-22. 2.B.1.5. Disconnect plug from generator voltage regulator. 2.B.1.6. Measure the resistance using an ohmmeter. Preselect measuring mode “resistance” and a suitable measuring range. Connect one probe of the ohmmeter to the grounding bolt (9, Figure 4) and the other probe i.a.w. the following list: Model Plug Contact BO105 excluding model D 104Pa / 204Pa G BO105 model D 108Pa / 208Pa F 2.B.1.7. If the resistance reading is 0.5 ohms or less: -- Install engine cowling i.a.w. maintenance manual MBB--BO105, chapter 92-22. -- Attach wire temrinals to terminal E of the starter--generator using a nut and torque--tighten the nut to 25--26,5 Nm. Ensure that the wire terminals are cenrically aligned and that the wires are installed without tension. -- Install engine cowling i.a.w. MM, MBB-BO105, chapter 22. 2.B.1.8. Evaluation of the measuring reading: Measuring value Note Approval Proceed with accomplishment i.a.w. 0.5 ohms or less The ground reference line is not conencted to teh starter--generator. The heicopter is not affected by this Alert Service Bulletin all Section2.B.5. more than 0.5 ohms The ground reference line is connected to the starter--generator. The ground reference line must be retrofitted IFR Section2.B.2. Until the ground reference line is retrofitted, checks must be accomplished IFR Section 2.A. more than 0.5 ohms Checks must be accomplished. With accomplishment of SB BO105-90-104 the check will no longer be applicable without IFR Section 2.A. EFFECTIVITY All affected helicopter with IRF approval. 2.B.2. Disconnect wire from the starter--generator and cap and stow wire on the generator voltage regulator: April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 6 of 18 NOTE The wire connection on the starter--generator and on the generator voltage regulator is identical for system I and II. NOTE Some of the electrical identifications of the “BO105 model D” differ from the other BO105 models (see the table given below). In the accomplishment instructions the electrical identifications for the “BO105, excluding model D” are used. The electrical identifications for the “BO105 model D” are shown in italic letters The elctrical identifications for helicopters up to and inlcuding S/N 0160 may also differ from the others and are not described in this Service Bulletin. Model Electrical identifications BO105, excluding model D Electrical identifications BO105, model D Voltage regulator and plug 104Pa / 204Pa 108Pa / 208Pa Wire to the starter--generator terminal E P55F16N / P56F16N P28F16 / P27F16 wire to the voltage regulator, contact location G / F 25--18N / 32--18N (contact location G) 10--20 / 27--20 (contact location F) 2.B.2.1. Disconnect battery and external power supply from helicopter electrical system. 2.B.2.2. Remove engine cowling i.a.w. the MM MBB-BO105, chapter 22. 2.B.2.3. Loosen nut from terminal E of the starter--generator (see Figure 1) and store for reuse. 2.B.2.4. Disconnect wire P55F16N / P56F16N, (P28F16 / P27F16) (2, Figure 1) and, if necessary, the associated shield--grid lead from terminal E. Cut off wire P55F16N / P56F16N, (P28F16 / P27F16) and, if necessary, shield--grid lead immediately at the wire terminal. Slide heat--shrinkable sleeve onto wire ends and shrink on with a hot air blower. 2.B.2.5. Attach remaining wires to terminal E of the starter--generator using nut and torque--tighten to 25--26.5 Nm. While doing so, ensure that the wire terminals remain centrically aligned when they are tightened and that the wires are routed with a strain relief. 2.B.2.6. As needed, attach the capped and stowed wire P55F16N / P56F16N, (P28F16 / P27F16) and, if necessary, the shield--grid lead to installed wires using a lacing tape. 2.B.2.7. Install engine cowling i.a.w. MM MBB-BO105, chapter 22. 2.B.2.8. Loosen end ring from plug 104Pa / 204Pa, (108Pa / 208Pa) and disconnect plug from generator voltage regulator 104P / 204P, (108P / 208P) (Figure 2), (Figure 7) in the electrical master box. April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 7 of 18 2.B.2.9. Disconnect wire 25--18N / 32--18N, (10-20 / 27-20) from contact location “G”, “F” (see Wiring Diagram, Figure 5, 6), (8, 9). Cut off wire immediately after the contact. Slide heat--shrinkable sleeve onto wire end and shrink on with a hot air blower. 2.B.3. Retrofit wire harness: EFFECTIVITY All affected helicopters up to and inlcuding S/N 0160 with IFR approval 2.B.3.1. If necessary install grommet (3, Figure 2, 7) to a suitable position by drilling the installtion hole in the electrical master box housing using a drill bit dia. 14 mm EFFECTIVITY All affected helicopters with IFR approval 2.B.3.2. Route wire harness i.a.w. Figure 2, 3, (3, 7) and fix. If installed, route wire harness within attachment clamps and chafing protection. 2.B.3.3. Insert wire of wire connector SP1062VV / SP1063VV in plug 104Pa / 204Pa, (108Pa / 208Pa), contact location “G”, “F” (see Wiring Diagram, Figure 5, 6, (8 ,9)). 2.B.3.4. Screw end ring onto plug 104Pa / 204Pa, (108Pa / 208Pa). If necessary, fix wires. 2.B.3.5. If grounding bar (5, Figure 3) is installed as standard item of equipment: Screw wire teminals (1, Figure 3) of wires P98A(B)16N / P99A(B)16N onto grounding bar (5) i.a.w. Detail A, Figure 3. 2.B.4. If the grounding bar is not a standard item of equipment: 2.B.4.1. If grounding bar is not installed as standard item of equipment: Loosen installed grounding bolt (9, Figure 4). Note installation sequence of the individual parts for their later re--installation. Drill out installed rivets. Position grounding bracket (3) and copy using drill bit dia. 5.2 mm ( , Figure 4). Remove insulating surface protection layer from both sides of the contact surfaces ( ). Position grounding bracket (3) to structure. Re--install old grounding bolt (9) as noted (see Figure 4). Install new grounding bolt i.a.w. Figure 4 with wire terminals of wires P98A(B)16N / P99A(B)16N. Seal both grounding bolts using sealing compound CM 6056 ( , Figure 4). 2.B.4.2. Apply PU--lacquer (CM 478. CM 479, CM 480) onto bare metal surfaces of the grounding connection (Figure 3, 4). 2.B.5. Perform functional test: 2.B.5.1. Accomplish check and adjustment of the generator voltage i.a.w. MM MBB-BO105, chapter 92-17. April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 8 of 18 2.B.5.2. Confirm accomplishment of this Alert Service Bulletin with an entry in the historical record of the helicopter. 2.C. Conclusions (Not applicable) 3. MATERIAL INFORMATION (Not applicable) 3.1. Required Parts per helicopter if replacement is necessary: 3.1.1 Retrofit kit SB-105-90A-103-3.1.1 No. Qty Nomenclature Part No. 1 a.n.* Wire terminal ** 320564 1 a.n.* Grommet *** LN9240--10X2 EFFECTIVITY Helicopter BO105 Serie D 3.1.2 Retrofit kit SB-105-90A-103-3.1.2 No. Qty Nomenclature Part No. 1 1 Wire harness Retro GCU BO105 Serie D 105-90085 2 a.n.* PU lacquer CM 478 3 a.n.* Hardener CM 479 4 a.n.* Thinner CM 480 EFFECTIVITY Additional for helicopter, if grounding bar is not installed as standard item of equipment. 3.1.3 Material kit SB-105-90A-103-3.1.3 No. Qty Nomenclature Part No. 1 1 Grounding bracket 105-90079.01 2 1 Hexagon heade screw LN9038K05018 3 1 Washer LN9016-05K 4 1 Washer LN9166-5,3N 5 1 Nut LN29790M5 6 a.n.* PU lacquer CM 478 7 a.n.* Hardener CM 479 8 a.n.* Thinner CM 480 9 a.n.* Sealing compound CM 6056 April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 9 of 18 EFFECTIVITY Helicopters BO105, excluding Model D. 3.1.4 Material kit SB-105-90A-103-3.1.4 No. Qty Nomenclature Part No. 1 1 Wire harness Retro GCU BO105 105-90081 2 a.n.* PU lacquer CM 478 3 a.n.* Hardener CM 479 4 a.n.* Thinner CM 480 * a.n. = as needed. ** If this item is needed, a separate order has to be placed for it. *** This item is needed for the retrofit of the ground reference line up to helicopters S/N 0160 and must be ordered separately. 3.2. Discarded Parts per helicopter if replacement is necessary: (Not applicable) April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 10 of 18 Starter--Generator Figure 1 1 Wire terminal 320564 2 Wire P28F16 / P27F16 (BO105 model D) P55F16N / P56F16N (BO105 excluding model D) 3 Shield--grid lead 1 25-26,5 Nm 2 3 April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 11 of 18 Typical Installation of Wire Harness (BO105, excluding Model D) Figure 2 Continuation see Figure 31 1 Wire harness 105-90081 2 Electrical master box 3 Grommet LN9240--10X2 2 2 204P 104P 204Pa 104Pa If necessary position it at a suitable position (diameter of the borehole =14 mm) 3 April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 12 of 18 Typical Installation of Wire Harness with Grounding Bar installed as Standard Equipment Figure 3 1 Wire terminal 2 Nut (LN9348-05) 3 Spring washer (DIN137A5B3C) 4 Washer (LN9016-05K) 5 Grounding bar 6 Screw (LN9038-05018) 7 Wire harness 105-90081 BO 105 excluding model D 105-90085 BO 105 model D 1 2 3 4 2x 5 6 Positions 2--6 are already installed on the helicopter. Connect wire P99A16N and P99B16N Connect wire P98A16N and P98B16N 7 DetailA Faying surface free from insulating surface protection layer. Apply PU lacquer (CM 478, CM 479, CM 480) onto bare metal surfaces after assembly. A View A (from Figure 2) 5 April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 13 of 18 Installation of Wire Harnesses without Grounding Bar installed as Standard Equipment Figure 4 1 Hexagon heaad screw LN9038K05018 2 Structure 3 Grounding bracket 105--90079.01 4 Washer LN9166--5,3N 5 Wire terminal 6 Washer LN9016--05K 7 Nut LN29790M5 8 Wire harness 105-90081 BO 105 excluding model D 105-90085 BO 105 model D 9 Installed grounding bolts Faying surface free from insulating surface protection layer. Apply PU lacquer (CM 478, CM 479, CM 480) onto bare metal surfaces after assembly. Drill out installed rivets. Position grounding bracket and drill using drill bit dia. 5.2 mm. New grounding bolt 1 2 3 4 5 x4 6 7 3 3 8 2 9 Installed grounding bolt Seal with sealing compound VM 6056. April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 14 of 18 Wiring Diagram with Grounding Bars as Standard Item of Equipment (BO105 excluding model D) Figure 5 Before modification After Modification Valid S/N 0161--S/N 9999 April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 15 of 18 Wiring Diagram without Grounding Bar as Standard Item of Equipment (BO105 excluding model D) Figure 6 Before modification After Modification Valid S/N 0161--S/N 9999 April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 16 of 18 Typical Installation of Wire Harness (BO105 model D) Figure 7 108P 208P 108Pa 208Pa Continuation see Figure 3 1 1 Wire harness 105-90085 2 Electrical master box 3 Grommet LN9240--10X2 2 A View A 2 3 If necessary, position it at a suitable position (diameter of the borehole=14 mm) April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 17 of 18 Wiring Diagram with Grounding Bar installed as Standard Equipment (BO105 model D) Figure 8 Before modification After Modification Valid S/N 0161--S/N 9999 April 03, 2006 Rev. 4, June 21, 2010 ASB BO105-90-103 Page 18 of 18 Wiring Diagram without Grounding Bar installed as Standard Equipment (BO105 model D) Figure 9 Before modification After Modification Valid S/N 0161--S/N 9999