C130JPocketGuide.pdf — page 15

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ENVIRONMENTAL CONTROL SYSTEM
• The aircraft’s environmental control system (ECS)  
is capable of stabilizing the cockpit environment 
from a heat soak temperature condition at external 
­ambient temperature of +120°F (+49°C) to 
+84°F (+28.8°C) within 30 minutes from cooling 
operation ECS start. The ECS is capable of 
increasing the cabin average temperature from 
-22°F (-30°C) to +41°F (+5°C) within 20 minutes.
• Cargo-floor heating is accomplished by using hot 
air circulating through an underfloor manifold.
• A forced-air cooling system is provided for the 
flight-station displays and certain rack-mounted 
avionics and electrical equipment.
• A system for pressurizing the flight station  
and cargo compartment is supplied by engine 
compressor bleed air. This electronically controlled 
pneumatic system is capable of maintaining  
a maximum of 8,000-foot cabin altitude at  
32,200-foot flight altitude. The aircraft is 
pressurized and depressurized in accordance with 
a preprogrammed schedule and under rate control 
while in the automatic mode. A separate backup 
manual control of the pressurization system 
provides outflow valve operation in case of a 
failure in the automatic system.
FUEL SYSTEM
• The fuel system uses a common cross-ship 
manifold that serves as a refueling system, a fuel 
supply crossfeed, a direct feed system, a ground 
defueling system, and a fuel jettisoning system.  
The fuel system consists of tanks, pumps, piping, 
valves, flowmeters, strainers, and quantity  
gage units.
• Fuel system design and performance is based on 
the use of fuel conforming to JP-8 (MIL-T-83133).
• The system is compatible with JP-4, JP-5, Jet A,
	 Jet A-1, and Jet B fuels with or without anti-icing 
Major Systems
ELECTRICAL
• The electrical system includes four regulated 
transformer rectifier units, five AC generators, 
controls, and conversion equipment needed  
to satisfy and control the diversified power 
requirements of the various electrical and 
electronic equipment and other systems.  
Secondary distribution uses electronic and 
electromechanical circuit breakers.
• Four 40/50-kVA oil-cooled, three-phase AC 
generators constitute the primary AC power source. 
Each engine-driven generator has an overtorque 
shaft ­disconnect and an individual generator 
control unit. A fifth 40/50-kVA air-cooled, three-
phase AC generator is mounted on the auxiliary 
power unit as an additional AC power source.
• Two 24-volt, 42-ampere-hour (beginning of life), 
sealed, lead acid, and maintenance-free batteries 
are installed in a battery compartment in the lower 
left forward fuselage. A control switch in the flight 
­station disconnects the batteries from the electrical 
system. With fully charged batteries, sufficient 
­battery power is available to operate standby 
instruments and other flight-critical components for 
approximately 30 minutes after complete loss of 
­primary aircraft power. When required, one battery 
can provide electrical power for APU starting.
• Four regulated 200-ampere transformer rectifiers 
convert AC power to DC power. Two 1-kVA 
inverters provide uninterruptable electrical  
power for the essential avionics bus and the  
main avionics bus.
• Regulated power supplies (RPSs) provide filtered 
and regulated DC power to the flight station 
consoles. The RPS is powered by two independent 
28-VDC power sources.
Major Systems