Cabin atmosphere control systems Flashcards
(19 cards)
what are the two groups of independent cabin compressors
positive displacement and centrifugal
what is the principal control of a pressurization system
an outflow valve
what method is used by some turbine powered aircraft for pressurization
bleed air from the turbine engine compressor
what is a roots blower
an engine driven compressor
what pressurization control unit will change the position of an outflow valve
the cabin pressure controller
what is the function of ventilating air in a combustion heater
it is the air that is warmed and sent into the cabin
what are sources of ventilating air in a combustion heater
a blower/fan or ram air
what components are used in an air cycle cooling system
an expansion turbine, air to air heat exchanger and various valves
what causes a temperature drop in air cycle cooling system
the compressed air performs the work of turning a turbine and it undergoes a pressure and temperature drop
how does a water separator remove moisture from the air
the moist air passes through vanes that swirl the air and the droplets are collected and drained
what is vapor cycle cooling
a closed system in which a refrigerant is circulated through tubing and a variety of components to remove heat from the aircraft
what components are in a vapor cycle cooling system
a receiver dryer, evaporator, compressor, condenser and expansion valve
how does a continuous flow oxygen system operate
oxygen flows from a charged cylinder through a high pressure line to a reducing valve and to mask outlets
how does a basic pressure demand oxygen system operate
oxygen flows from a charged cylinder to a pressure demand regulator, adjustable by each crew member
what must be accomplished if an oxygen system has been open to atmosphere for 2 hours or more
the system must be purged to remove moisture
what is used to purge oxygen lines of moisture
dry nitrogen, dry air or oxygen
what type of oxygen must be used in aircraft
aviator’s breathing oyxgen
why is oil added to a vapor cycle Freon system
to seal and lubricate the compressor
what safety precautions should be observed when servicing oxygen systems
clean, grease free tools, clothing, hands; no smoking or open or open flames within 50 feet; do not use adhesive tape of any kind
