Airframe Chapter 14 Flashcards
Is there any special requirement as to the type of oxygen used in an aircraft system, and if so, what is it?
Only aviator’s breathing oxygen should be used.
Describe the operating principles of a continuous flow oxygen system.
High pressure oxygen flows from the storage cylinder to a pressure regulator where it’s pressure is reduced and then to the mask outlet whenever the system is turned on.
Describe the operation principle of a pressure demand oxygen system.
Demand systems allow oxygen to flow from the cylinder to the regulator and then to the mask only when the user inhales. Pressure demand systems provide oxygen to the mask at higher than atmospheric pressure when used at extremely high altitudes, forcing oxygen into the user’s lungs.
What should be used to purge an oxygen system of moisture?
Oxygen, dry air, or dry nitrogen.
What action must be taken when an oxygen system has been open to the atmosphere?
The system must be purged of any moisture.
Describe the safety precautions that should be observed when servicing oxygen systems.
Avoid all contact with petroleum based oil or grease, don’t smoke, keep everything very clean, service system outdoors if at all possible, and keep the caps on the bottles to protect the valves.
What is a Roots blower?
A type of engine driven compressor.
Name two different types of independent cabin air compressors?
Positive displacement and centrifugal.
What is the source of pressurization air in most jet aircraft?
Engine bleed air.
What device provides the principle means of controlling cabin pressure?
The outflow valve.
What unit regulates the position of an outflow valve?
The cabin pressure controller.
Name several methods used on reciprocating engine aircraft for providing heated cabin air.
Exhaust shroud heat exchangers, combustion heaters, and electric heaters.
What is the function of the ventilating air in a combustion heater?
Ventilating air transports the heat from the heater into the cabin and prevents combustion gases from entering the cabin if the combustion chamber develops a crack.
What are the sources of ventilating air in a combustion heater?
Ram air in flight, a blower on the ground and possibly a compressor if the airplane is pressurized.
Name the basic components of an air cycle cooling system.
The compressor and expansion turbine, heat exchangers, and various valves.