ENGINEMAN  1  &  C Table  4-1.—Related  Propulstion  System  Components System Name/Description Main   Reduction   Gear,   Mounting   and Coupling  for  Gear-Driven  Hydraulic  Oil Pump. Propeller Shaft. Interconnecting Hydraulic Oil Piping. Head Tank, Sump Tank and Hydraulic Oil Supply  plus  Associated  Components,  and Fittings. Central   Control   Station   (CCS)   Controls and Indicators. Related propulsion system components, which are necessary for the operation of a CRP propeller but which are not part of the CRP propeller are listed in table 4-1. Let’s look at some of these com- ponents,  along  with  other  components,  shown  in table  4-2. Hub/Blade Assembly The propeller’s hub/blade assembly (see figure 4-6), attached to the main propulsion propeller shaft,  provides  the  mounting  for  the  propeller blades  and  houses  the  blade  turning  mechanism for rotating and holding the pitch position of the blades. Attached to the after end of the hub body are the hub cone and the hub cone end cover. These items form the chamber for the servomotor piston. The hub body is fitted to the tailshaft by guide  pin  dowels  which  also  transmit  the  torque Table  4-2.—CRP  Propeller  Hardware  Components HUB BLADE ASSEMBLY HYDRAULIC  SYSTEM Hub Assembly, LG Hub  assembly.  RH Blades (Set of 5). LH Blades (Set of 5). RH VALVE ROD ASSEMBLY Piping,  Couplings  &  Guides,  Port Piping, Couplings & Guides, Stbd OIL  DISTRIBUTION  BOX DD Box Assembly. Port DD Box Assembly, Stbd. ELECTRONIC PITCH CONTROL SYSTEM Hydraulic  Oil  Power  Module,  P/S (each including): Electronic Pitch Control Assembly, P/S Suction Strainer (1) Hydraulic Oil Pump, Coupling Feedback Potentiometer, P/S and Motor (1) Readout  Potentiometer,  P/S Duplex Discharge Filters (3) Air Bleed Valves (2) LOCAL PITCH INDICATOR Pressure  Control  Assembly,  con- sisting of: sequence and relief valve,  unloading  and  check valve,  reducing  Valve,  and control oil relief valve. Manual Bypass Valve (1) Gauge Panels (2) Manifold Block Assembly, P/S (each including): Electra-hydraulic  Servo  Control Valve (1) Manual  Pitch  Control  Valve  (1) Manual Changeover Valves (2) Standby Hydraulic Oil Pump (gear driven), P/S Suction Strainer (gear pump), P/S Return Check Valve, P/S Pitch Indicating Assembly, P/S EMERGENCY  PITCH  SETTING Emergency Hand Pump Assembly, P/S PRAIRIE  AIR  SYSTEM Rotoseal,  P/S Check Valve (hub), LH/RH Check Valve (OD Box), P/S Prairie Air Tube Assy.. P/S Connectors,  Prairie  Air,  Hub  to Blade (Set of 5). LH/RH 4-12