HYDRAULICS
What provides system A and B reservoir pressure
Bleed air
Sby system is connected to Sys B reservoir for pressure
HYDRAULICS
Minimum fuel for ground operation of electric motor-driven pumps
760kgs in the related main tank
HYDRAULICS
System A Leak in Electric Driven Pump - what does the fluid level reduce to
indicates 0%
HYDRAULICS
System A Leak in Engine Driven Pump - what does the fluid level reduce to
indicates approx 20% as fluid is provided by a standpipe
HYDRAULICS
System B Hydraulic Leak in Electric Pump
indicates 0% and system B pressure is lost. Fluid remaining in system B reservoir is sufficient for PTU operation
HYDRAULICS
System B Hydraulic Leak in Engine Pump
indicates 0% and system B pressure is lost. Fluid remaining in system B reservoir is sufficient for PTU operation
HYDRAULICS
Purpose of the PTU
Supplies the additional volume of hydraulic fluid needed to operate the autoslats and leading edge flaps and slats at the normal rate when system B engine-driven hydraulic pump volume is lost.
HYDRAULICS
PTU operates automatically when all of the following conditions exist:
System B engine-driven pump hydraulic pressure drops below limits
airborne
flaps are less than 15 but not up.
SFP
flaps not up
HYDRAULICS
Landing Gear Transfer Unit Purpose
provides volume of hydraulic fluid needed to raise landing gear at normal rate when Sys A engine-driven pump volume is lost.
Volume provided by the System B engine driven pump
HYDRAULICS
Landing Gear Transfer Unit operates when:
Airborne
No. 1 engine RPM drops below a limit value
landing gear leaver is positioned UP
either main landing gear is not up and locked
HYDRAULICS
Standby Hydraulic System powers:
uses a singel electric motor-driven pump to power:
thrust reversers
rudder
leading edge flaps and slats (extend only)
standby yaw damper
HYDRAULICS
Standby Hydraulic System Manual Operation Description positioning FLT CONTROL switch to STBY RUD:
Positioning either FLT CONTROL switch to STBY RUD:
HYDRAULICS
Standby Hydraulic System
positioning ALTERNATE FLAPS switch to ARM
HYDRAULICS
Standby Hydraulic System Automatic Operation
initiated:
OR
main PCU force flight monitor (FFM) trips
HYDRAULICS
Standby Hydraulic System Automatic Operation does what:
HYDRAULICS
Standby Hydraulic System Leak in reservoir quantity decreases to
0%
HYDRAULICS
Standby Hydraulic System leak in reservoir B system quantity decreases to
72%
HYDRAULICS
Variations in hydraulic quantity indications occur when
note: have little effect on systems operation.