HSU-1 Hydraulic Fluid Servicing Unit
The HSU-1 Hydraulic Fluid Servicing Unit (fig.
1-11) is a portable, hand pump operated, hand-carried
unit, which is used for servicing main hydraulic
systems, subsystems, bleeding brakes, flushing, and
priming system components. It has a fluid holding
capacity of 3 gallons, accepts a standard 1-gallon
container, and uses it as a fluid reservoir. It also
contains an integral 2-gallon reservoir. The unit is made
of cast aluminum and has a sight gauge on the side to
view the total contents within the holding reservoir.
H-250-1 Hydraulic Fill Unit
The H-250-1 Hydraulic Fill Unit (fig. 1-12) is
similar in operation to the HSU-1. It is designed to use
the standard 1-gallon can of hydraulic fluid and to
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dispense it, contamination free, to the aircraft systems.
Figure 1-12.--H-250-1 hydraulic fill unit.
This is done by pumping the fluid from the original can,
which is sealed into the unit and acts as the reservoir,
directly to the aircraft. It is a portable, hand-pump
Q1-37.
Which of the following hydraulic units uses a
operated, hand-carried unit.
55-gallon drum of hydraulic fluid?
Q1-36.
Which of the following portable hydraulic
1.
A/M27T-5
power supply units is powered by an external
2.
HSU-1
power source?
3.
A/M27M-10
4.
H-250-1
1.
HSU-1
2.
A/M27M-10
AIRCRAFT TOWING EQUIPMENT
3.
A/M27T-5
4.
A/M27T-7
The tow tractor is the only safe means of moving
the majority of today's aircraft. They are also used to
move support equipment specifically equipped to be
towed, such as mobile electric power plants, portable
hydraulic power supplies, maintenance stands, etc.
These are the only authorized uses for tow tractors.
As a rule of thumb, maximum aircraft weight that a
tow tractor can handle is 10 times the drawbar pull of
the tractor. In other words, a tractor that has a drawbar
pull of 7,500 pounds is capable of towing an aircraft
that weighs 75,000 pounds.
A/S32A-37 Tow Tractor
The A/S32A-37 Tow Tractor (fig. 1-13) is also
known as the TA-35. It is a six-cylinder diesel engine
powered, four-wheel drive tractor used for moving
heavy shore-based aircraft. The automatic transmission
has six forward speeds and three reverse speeds. This
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tractor can be configured as a Class I or Class II, and
can tow aircraft weighing up to 200,000 and 350,000
pounds, respectively.
Figure 1-11.--HSU-1 hydraulic fluid servicing unit.
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