737 MAX Flight Crew Operations Manual
Hydraulics -
System Description
13.20.6
MN-FLT-OH-201
• leading edge flaps and slats (extend only)
• standby yaw damper.
Manual Operation
Positioning either FLT CONTROL switch to STBY RUD:
• activates the standby electric motor–driven pump
• shuts off the related hydraulic system pressure to ailerons, elevators and
rudder by closing the flight control shutoff valve
• opens the standby rudder shutoff valve
• deactivates the related flight control LOW PRESSURE light when the
standby rudder shutoff valve opens
• allows the standby system to power the rudder and thrust reversers.
• illuminates the STBY RUD ON, Master Caution, and Flight Controls
(FLT CONT) lights.
Positioning the ALTERNATE FLAPS master switch to ARM, (refer to Chapter 9,
Flight Controls for a more complete explanation):
• activates the standby electric motor–driven pump
• closes the trailing edge flap bypass valve
• arms the ALTERNATE FLAPS position switch
• allows the standby system to power the leading edge flaps and slats and
thrust reversers.
Automatic Operation
Automatic operation is initiated when the following conditions exist:
• loss of system A or B, and
• flaps extended, and
• airborne, or wheel speed greater than 60 kts, and
• FLT CONTROL switch A or B Hydraulic System ON
OR:
• the main PCU Force Fight Monitor (FFM) trips
Automatic operation:
• activates the standby electric motor–driven pump
• opens the standby rudder shutoff valve
• allows the standby system to power the rudder and thrust reversers.
• illuminates the STBY RUD ON, Master Caution, and Flight Controls
(FLT CONT) lights.
October 26, 2021