Super 80 Professional – AOM
HYDRAULICS
Section 17 Page 2
Super 80 Professional – Aircraft Operating Manual
Coolsky, 2018
GENERAL
The MD-80 hydraulic system consists of
independent left and right systems. Each
system has a reservoir and is pressurized by a
single engine-driven pump.
Hydraulic Supply
The left and right hydraulics reservoir is
located in the left and right main gear
wheel wells. Each reservoir supplies fluid to its
own system respectively.
Hydraulic Pumps
The left hydraulic system is pressurized by a
pump mounted on the left engine and the
right hydraulic system is pressurized by a
pump mounted on the right engine. Each of
the engine-driven pumps can operate in a
high pressure or low pressure mode. The high
pressure mode provides 3000 PSI and is used
for taxi, take-off and landing. The low
pressure mode provides 1500 PSI and is
selected on the After Take-off Checklist to
reduce wear on the system.
An auxiliary, electrical pump is installed in
the right hydraulic system and is designed
for continuous operation at 3000 PSI.
A power transfer pump is installed to transfer
pressure between the left and right hydraulic
system. Note that there is no transfer of fluid
between the left and right hydraulic system.
For the transfer pump to operate, either the
left or right system must be pressurized to
provide energy to drive the transfer pump.
The transfer pump is normally used during
taxi, take-off and landing as a backup
source of pressure.
Hydraulic System Fluids
Standard:
Chevron Hyjet IVA
Substitutes:
Chevron Hyjet IV
Monsanto Skydrol 500B4
Skydrol LD4