Systems Flashcards
Engine Ice Protection
The engine uses two types of anti-ice protection:
- To protect the air inlet, some of the hot engine exhaust gases are scooped up and directed into the air inlet lip.
- To protect the engine, ice vanes are used which are moved into the airstream. These cause a slight deflection in the entering airflow, introducing a turn in the airstream. The accelerated moisture particles continue on to the discharge port, rather than entering the engine.
> Ice vanes are to be extended for all ground ops to minimize ingestion of ground debris. But turn it off to maintain oil temps within limits.
Governors & Props
Primary: maintains 1600-2000 RPM.
• Over-speed: if primary exceeds 2080 RPM (104%) or 2120 RPM (106%)
• Fuel-Topping: restricts fuel flow should overspeed fail
Propellor
• Standard: 2000 RPM, Max.: 2120 RPM, Max. Max.: 2200 RPM
Auto-Feather:
• Reduce RPM to 500 (just above 400) to keep it running
• Reduce further to 400’ to disarm the good side
• RPM to 200 lbs?, it feathers the engine
Pressurization
Bleed air from the engine compressor section is used to supply airplane pressurization.
• Engine bleed is mixed with ambient air to form a suitable air density mixture.
• The FCU and BLEED AIR VALVE switches, control the mixture.
• If this switch is positioned to ENVIRonmental OFF or INSTrument and ENVIRonmental OFF, the bleed-air valve will be closed.
• When positioned to OPEN, air is routed through a heat exchanger, then into a mixing plenum. It mixes with recirculated air, is routed to the outlet ducts, and is introduced into the cabin.
• The FLOW CONTROL UNIT regulates the mixture of engine bleed air for pressurization with ambient air. Pressurization air is routed through the wings and, finally, into the cabin where it is used for heating, cooling, and pressurization.
> Cabin Pressure Switch
• in the DUMP (forward lever locked) position, opens the safety valve, allowing the cabin to depressurize and stay unpressurized.
• In the PRESS position, the safety valve closes and the pressurization controller takes command of the outflow valve.
• In the TEST (aft, spring-loaded to the center) position, the safety valve is held closed, bypass- ing the landing gear safety switch to allow cabin pressurization tests on the ground.
> Operation
• Ensure the CABIN PRESSure switch is placed in the PRESSure position.
• At T/O: Set the cabin altitude selector knob until the ACFT ALT (inner) scale on the indicator dial to read an altitude approximately 500-1,000 feet above the planned cruise pressure altitude. (Ex. Select 26 on the inner scale if flying at FL 250). The RATE control knob is adjusted as desired. When the index mark is set between the 9 o’clock and 12 o’clock positions, the most comfortable rate of climb is maintained.
• At Descent: The cabin altitude selector is set to indicate a cabin altitude of approximately 500 feet above the landing field pressure altitude
Ice protection systems
TBA
Bleed Air
Each engine compressor supplies bleed air for the pressurization and pneumatic systems. The bleed air used for pressurization is routed from the engine to a Flow Control Unit (FCU) then into the pressure vessel. This same air is conditioned for environmental use.
Bleed air used for the pneumatic system (indicated by Pneumatic Pressure Guage) is used for:
• surface & brake deice,
• rudder boost,
• door seal,
• bleed-air warning system,
• the flight hour meter,
• landing gear hydraulic reservoir ( if installed).
Through the use of a venturi, vacuum suction is developed for:
• flight instruments,
• pressurization controller operation
• deice boots
One engine can supply sufficient bleed air for all associated systems.
Bleed air entering the cabin, used for pressurization and environmental functions, is controlled by the two BLEED AIR VALVES switches which are marked OPEN, ENVIR OFF, and INST & ENVIR OFF.
When the switch is in the OPEN position, both the environmental flow control unit and the pneumatic instrument air valve open.
When the switch is in the ENVIR OFF position, the environmental flow control unit closes and the pneumatic instrument air valve remains open.
In the INST & ENVIR OFF position, both the environmental and pneumatic flow valves are closed
Engine Ice Protection
The engine uses two types of anti-ice protection:
- To protect the air inlet, some of the hot engine exhaust gases are scooped up and directed into the air inlet lip.
- To protect the engine, ice vanes are used which are moved into the airstream. These cause a slight deflection in the entering airflow, introducing a turn in the airstream. The accelerated moisture particles continue on to the discharge port, rather than entering the engine.
> Ice vanes are to be extended for all ground ops to minimize ingestion of ground debris. But turn it off to maintain oil temps within limits.
Governors & Props
Primary: maintains 1600-2000 RPM.
• Over-speed: if primary exceeds 2080 RPM (104%) or 2120 RPM (106%)
• Fuel-Topping: restricts fuel flow should overspeed fail
Propellor
• Standard: 2000 RPM, Max.: 2120 RPM, Max. Max.: 2200 RPM
Auto-Feather:
• Reduce RPM to 500 (just above 400) to keep it running
• Reduce further to 400’ to disarm the good side
• RPM to 200 lbs?, it feathers the engine
Pressurization
Bleed air from the engine compressor section is used to supply airplane pressurization.
• Engine bleed is mixed with ambient air to form a suitable air density mixture.
• The FCU and BLEED AIR VALVE switches, control the mixture.
• If this switch is positioned to ENVIRonmental OFF or INSTrument and ENVIRonmental OFF, the bleed-air valve will be closed.
• When positioned to OPEN, air is routed through a heat exchanger, then into a mixing plenum. It mixes with recirculated air, is routed to the outlet ducts, and is introduced into the cabin.
• The FLOW CONTROL UNIT regulates the mixture of engine bleed air for pressurization with ambient air. Pressurization air is routed through the wings and, finally, into the cabin where it is used for heating, cooling, and pressurization.
> Cabin Pressure Switch
• in the DUMP (forward lever locked) position, opens the safety valve, allowing the cabin to depressurize and stay unpressurized.
• In the PRESS position, the safety valve closes and the pressurization controller takes command of the outflow valve.
• In the TEST (aft, spring-loaded to the center) position, the safety valve is held closed, bypass- ing the landing gear safety switch to allow cabin pressurization tests on the ground.
> Operation
• Ensure the CABIN PRESSure switch is placed in the PRESSure position.
• At T/O: Set the cabin altitude selector knob until the ACFT ALT (inner) scale on the indicator dial to read an altitude approximately 500-1,000 feet above the planned cruise pressure altitude. (Ex. Select 26 on the inner scale if flying at FL 250). The RATE control knob is adjusted as desired. When the index mark is set between the 9 o’clock and 12 o’clock positions, the most comfortable rate of climb is maintained.
• At Descent: The cabin altitude selector is set to indicate a cabin altitude of approximately 500 feet above the landing field pressure altitude
Ice protection systems
TBA
Bleed Air
Each engine compressor supplies bleed air for the pressurization and pneumatic systems. The bleed air used for pressurization is routed from the engine to a Flow Control Unit (FCU) then into the pressure vessel. This same air is conditioned for environmental use.
Bleed air used for the pneumatic system (indicated by Pneumatic Pressure Guage) is used for:
• surface & brake deice,
• rudder boost,
• door seal,
• bleed-air warning system,
• the flight hour meter,
• landing gear hydraulic reservoir ( if installed).
Through the use of a venturi, vacuum suction is developed for:
• flight instruments,
• pressurization controller operation
• deice boots
One engine can supply sufficient bleed air for all associated systems.
Bleed air entering the cabin, used for pressurization and environmental functions, is controlled by the two BLEED AIR VALVES switches which are marked OPEN, ENVIR OFF, and INST & ENVIR OFF.
When the switch is in the OPEN position, both the environmental flow control unit and the pneumatic instrument air valve open.
When the switch is in the ENVIR OFF position, the environmental flow control unit closes and the pneumatic instrument air valve remains open.
In the INST & ENVIR OFF position, both the environmental and pneumatic flow valves are closed
Engine Ice Protection
The engine uses two types of anti-ice protection:
- To protect the air inlet, some of the hot engine exhaust gases are scooped up and directed into the air inlet lip.
- To protect the engine, ice vanes are used which are moved into the airstream. These cause a slight deflection in the entering airflow, introducing a turn in the airstream. The accelerated moisture particles continue on to the discharge port, rather than entering the engine.
> Ice vanes are to be extended for all ground ops to minimize ingestion of ground debris. But turn it off to maintain oil temps within limits.
Governors & Props
Primary: maintains 1600-2000 RPM.
• Over-speed: if primary exceeds 2080 RPM (104%) or 2120 RPM (106%)
• Fuel-Topping: restricts fuel flow should overspeed fail
Propellor
• Standard: 2000 RPM, Max.: 2120 RPM, Max. Max.: 2200 RPM
Auto-Feather:
• Reduce RPM to 500 (just above 400) to keep it running
• Reduce further to 400’ to disarm the good side
• RPM to 200 lbs?, it feathers the engine
Pressurization
Bleed air from the engine compressor section is used to supply airplane pressurization.
• Engine bleed is mixed with ambient air to form a suitable air density mixture.
• The FCU and BLEED AIR VALVE switches, control the mixture.
• If this switch is positioned to ENVIRonmental OFF or INSTrument and ENVIRonmental OFF, the bleed-air valve will be closed.
• When positioned to OPEN, air is routed through a heat exchanger, then into a mixing plenum. It mixes with recirculated air, is routed to the outlet ducts, and is introduced into the cabin.
• The FLOW CONTROL UNIT regulates the mixture of engine bleed air for pressurization with ambient air. Pressurization air is routed through the wings and, finally, into the cabin where it is used for heating, cooling, and pressurization.
> Cabin Pressure Switch
• in the DUMP (forward lever locked) position, opens the safety valve, allowing the cabin to depressurize and stay unpressurized.
• In the PRESS position, the safety valve closes and the pressurization controller takes command of the outflow valve.
• In the TEST (aft, spring-loaded to the center) position, the safety valve is held closed, bypass- ing the landing gear safety switch to allow cabin pressurization tests on the ground.
> Operation
• Ensure the CABIN PRESSure switch is placed in the PRESSure position.
• At T/O: Set the cabin altitude selector knob until the ACFT ALT (inner) scale on the indicator dial to read an altitude approximately 500-1,000 feet above the planned cruise pressure altitude. (Ex. Select 26 on the inner scale if flying at FL 250). The RATE control knob is adjusted as desired. When the index mark is set between the 9 o’clock and 12 o’clock positions, the most comfortable rate of climb is maintained.
• At Descent: The cabin altitude selector is set to indicate a cabin altitude of approximately 500 feet above the landing field pressure altitude
Ice protection systems
TBA
Bleed Air
Each engine compressor supplies bleed air for the pressurization and pneumatic systems. The bleed air used for pressurization is routed from the engine to a Flow Control Unit (FCU) then into the pressure vessel. This same air is conditioned for environmental use.
Bleed air used for the pneumatic system (indicated by Pneumatic Pressure Guage) is used for:
• surface & brake deice,
• rudder boost,
• door seal,
• bleed-air warning system,
• the flight hour meter,
• landing gear hydraulic reservoir ( if installed).
Through the use of a venturi, vacuum suction is developed for:
• flight instruments,
• pressurization controller operation
• deice boots
One engine can supply sufficient bleed air for all associated systems.
Bleed air entering the cabin, used for pressurization and environmental functions, is controlled by the two BLEED AIR VALVES switches which are marked OPEN, ENVIR OFF, and INST & ENVIR OFF.
When the switch is in the OPEN position, both the environmental flow control unit and the pneumatic instrument air valve open.
When the switch is in the ENVIR OFF position, the environmental flow control unit closes and the pneumatic instrument air valve remains open.
In the INST & ENVIR OFF position, both the environmental and pneumatic flow valves are closed
