SECTION I. EQUIPMENT DESCRIPTION AND DATA

TM 1-1520-238-T-5 7–2 Change 1 SECTION I. EQUIPMENT DESCRIPTION AND DATA 7–1. EQUIPMENT CHARACTERISTICS, CAPABILITIES, AND FEATURES 7–1 a. Characteristics. (1) The primary hydraulic system provides hydraulic power for the operation of the main rotor and tail rotor servocylinders. (2) The utility hydraulic system provides hydraulic power for the operation of the main rotor and tail rotor servocylinders, auxiliary power unit (APU) start motor, rotor brake, hydraulically operated weapon system components and provides a source of stored high pressure fluid for emergency operation of the flight control servocylinders. (3) The pressurized air system (PAS) cleans, pressurizes, regulates and distributes air to pneumatically operated systems and components. b. Capabilities and Features. (1) The primary hydraulic system provides 3000 psi hydraulic fluid pressure to hydraulically operated components. Flow rate is 6.0 gallons per minute (gpm) and capacity is three quarts of MIL–H–83282 or MIL–H–5606. The primary hydraulic system is serviced and bled using ground service equipment (GSE) through the GSE panel. External primary pressure is supplied, through the GSE panel, to provide ground hydraulic power operation for flight controls. (2) The utility hydraulic system provides 3000 psi hydraulic fluid pressure to hydraulically operated components. Flow rate is 6.0 gpm and capacity is 2.6 gallons of MIL–H–83282 or MIL–H–5606. The system is serviced and bled using GSE through a UTILITY GSE panel. External primary pressure is supplied, through the GSE panel, to provide ground hydraulic power operation for the utility system. (3) The PAS system provides 35 psi heated air to pneumatically operated components and has three modes of operation: primary, secondary and external. Engines 1 and 2, or the APU provides primary operation to drive the shaft driven compressor (SDC), secondary operation uses bleed air from engine 1, and external operation uses external air from the aviation ground power unit (AGPU). 7–2. LOCATION AND DESCRIPTION OF MAJOR COMPONENTS 7–2 a. Primary Hydraulic System. The primary hydraulic system (fig. 7–1) consists of the primary hydraulic pump, primary hydraulic manifold, primary GSE panel, longitudinal servocylinder, lateral servocylinder, collective servocylinder, and the directional servocylinder. (1) Primary Hydraulic Pump. The primary hydraulic pump, located on the left forward drive pad of the main transmission accessory geartrain housing, pressurizes and transfers fluid for system operation. The primary hydraulic pump is a constant pressure, variable delivery, piston–type pump driven by the main transmission accessory geartrain. The external drive shaft mates with the main transmission accessory geartrain and is designed to shear under excessive loads. (2) Primary Hydraulic Manifold. The primary hydraulic manifold, located on the main transmission deck forward and left of the main transmission, stores, filters and routes hydraulic fluid for system operation. (3) Deleted.