05/18/16
Overview
The flight compartment control system controls the operation of the AC motor-driven pumps (ACMP), monitors the hydraulic system, and controls the firewall hydraulic shutoff valves.
Operation of the hydraulic system is controlled from the hydraulic panel located on the overhead control panel in the cockpit. Control of the firewall shutoff valves is effected by operation of the fire handles, or by dedicated hydraulic firewall shutoff switches on the overhead panel.
The engine indication and crew alerting system (EICAS) monitors the hydraulic system.
05/18/16
Hydraulic Control Panels
The hydraulic control panel controls the ACMPs. It has four toggle switches. The switch for ACMP 3A has an ON/OFF position. The switches for ACMPs 1B, 2B, and 3B have ON/OFF/AUTO positions. The switch for pump 3A has an ON/OFF position. In the AUTO position (with the flaps not at zero degree) the ACMPs will come on automatically prior to takeoff and landing or if a primary pump fails in flight.
Hydraulic Firewall Shutoff Valve Control Panel
The HYDRAULIC firewall shutoff valve (SOV) control panel controls the flow of hydraulic fluid to the engine driven pumps (EDPs). It has two pushbuttons; one for the left hydraulic firewall SOV, one for the right hydraulic firewall SOV. The flight crew can use this panel to close the flow of hydraulic fluid to an EDP that has a malfunction.
The switches have CLOSED/open positions. Push once on the switch to close the applicable SOV and stop the flow of hydraulic fluid to the EDP. Push again on the switch to open the applicable SOV and start the flow of hydraulic fluid to the EDP.
