Hydraulic power on the aircraft moves and operates different aircraft systems. The Global series aircraft consists of three fully independent and isolated hydraulic systems. Hydraulic pressure is used for all primary flight controls and spoilers, landing gear extension and retraction, nosewheel steering, brake systems and the thrust reversers. Each system has a primary ("A") pump and a backup ("B") pump.

All three systems operate at 3,000 psi (20,684.40 kPa), using a phosphate ester Type IV low-density fluid. All three systems are pressurized throughout normal aircraft operations.

Systems No. 1 and 2 are each powered by an engine-driven pump (EDP) and an AC-motor pump (ACMP). The ACMPs are used as essential pumps for critical flight phase and to support the EDPs in the event of failure in flight. Most components for systems No. 1 and 2 are located in the aft equipment bay. The No. 1 hydraulic system moves the flight controls and the left side thrust reversers. The No. 2 hydraulic system moves the flight controls, the landing gear actuators, the outboard brakes, and the right side thrust reversers.

System No. 3 is powered by two ACMPs. Hydraulic ACMP 3A normally runs continuously while ACMP 3B is used as an essential pump for critical flight phase and in support of the primary ACMP 3A in the event of failure in flight. Most components for system No. 3 are located in the left lower belly fairing area. The No. 3 hydraulic system moves the flight controls, the nose wheel steering, and the inboard brakes. The No. 3 hydraulic system also moves the emergency brakes and the landing gear.

Each hydraulic system uses a bootstrap reservoir for hydraulic fluid storage. This pressure provides a positive feed to the pumps at all aircraft altitudes and attitudes.In the event that all normal electrical power is lost, a ram air turbine (RAT) is deployed and will power an independent hydraulic pump for system No. 3.

The hydraulic tubing and fittings are designed for enhanced reliability, and quick-disconnect ports are provided for ground servicing. Connectors are also provided to allow the connection of a ground hydraulic cart to each hydraulic system.

The main hydraulic power system is controlled by the pilot or the copilot from the flight compartment. Two control panels installed on the overhead panel in the cockpit, each placarded "HYDRAULIC", enable the crew to operate all three systems .Visual indication of the hydraulic system status is displayed in the cockpit via the EICAS.

The hydraulic synoptic page shows the status of the three hydraulic systems. For each system, it shows flow lines, system pressure, fluid temperature and fluid reservoir quantity. It also shows all pumps, shut off valve (SOV) status and aircraft systems operated by the hydraulic system.

The EICAS primary page shows the cautions, advisory and status indications in the crew alerting system (CAS) message window. Data is sent to the EICAS primary page by the pressure transducer, the reservoir temperature transducer, and the reservoir quantity transducer. Data is also sent from the ACMP pressure switches and the firewall shut-off valves.

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