A Firewall Shutoff Valve enables isolation of the system in emergency conditions such as an engine fire. Operation of the Firewall Shutoff Valve also opens a ram air scoop on the right fuselage underside which introduces ambient ventilation air through the distribution system. This is used in the event of smoke in the cockpit or cabin.
The Pressure Relief Valve (PRV) is _____ poppet type control valve.
Vapor Cycle Cooling System (VCCS) operation - Moisture removed from the cabin air by each evaporator drains into a small holding tank below the rear baggage floor panel. The water is held in the tank until the cabin differential pressure is low enough for the tank outlet valve to open allowing the water to drain overboard.
If the Passenger oxygen control valve selector is set to AUTO, the CPCS will automatically select the passenger oxygen system on at a cabin altitude of _____ (or at a higher set point for high airfield operations).
With the passenger oxygen system pressurized the green PAX OXY annunciator will be shown in the ENVIRONMENT window of the systems MFD.
The air cycle system cools a portion of the bleed air and then mixes it with hot bleed air to provide the correct temperature.
Auxiliary heating operation - When the system is in operation the under floor fan runs continuously and the heater element is switched on when the under floor sensor reads below _____ and is switched off above + 11 deg.C.
If the aircraft descends more than _____ (from previous stable altitude), the CPCS goes into so called descent mode, for which the cabin is controlled towards the ELEV pressure altitude.
Similarly If the aircraft climbs more than 1,300 ft, (from previous stable altitude), the CPCS goes into so called climb mode, for which the cabin is controlled depending on aircraft altitude.
Maximum cabin pressure differential is:
If a takeoff occurs at an airfield greater than 10,000 feet, the cabin is commanded to 10,000 feet or below just after takeoff at a fast rate so that the cabin altitude reaches 10,000 feet prior to the aircraft exceeding _____
This is High Airfield Operation and the green HI FIELD annunciator will be shown in the ENVIRONMENT window until the aircraft climbs to above 25,000 feet.
The PC-12 has two auxiliary electrical heaters. A cabin heater and an underfloor heater. Only the cabin heater can be used for pre-heating on the ground when external power is connected.
One of the two auxiliary electrical heaters (cabin heater) is used to supplement the air cycle system during prolonged low temperature operations such as cruise at high altitude. The other heater (underfloor heater) heats the under floor avionic and electrical equipment. Both heaters can also be used for pre-heating the cabin and under floor equipment on the ground when external power is connected.
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The Crew Alerting System (CAS) window of the systems MFD displays a 'CABIN ALTITUDE red warning. What does it mean?
The PRV has a negative pressure relief function and will open to allow atmosphere air to enter the cabin to prevent the atmosphere to cabin differential pressure from exceeding a given limit.
The PRV is pneumatically actuated and is completely independent of the Outflow Valve (OFV) and Cabin Pressure Control Unit (CPCU) / Electronic Control and Monitoring Unit (ECMU).
During engine start (ECS switches in AUTO position) the Primary Shutoff Valve (PSOV) is automatically kept closed (no bleed air) and the auxiliary heaters and VCCS are inhibited. When the engine Ng reaches _____ the PSOV opens and bleed air becomes available.
The ACS will automatically shut down when the engine Ng is less than 62%.
Selection of the CABIN PRESSURE switch to the DUMP position will command the OFV to the fully open position with the effect of fully depressurizing the aircraft. DUMP will override the CPCU/ECMU altitude limit function and will open the outflow valve at any cabin altitude up to 25,000 ft.
Selection of the CABIN PRESSURE switch to the DUMP position will command the OFV to the fully open position with the effect of fully depressurizing the aircraft. DUMP will override the CPCU/ECMU altitude limit function and will open the outflow valve at any cabin altitude.
Due to the system design only a temperature difference of up to a maximum of _____ between the cabin and cockpit can be set.
After more than 5 deg.C movement of one slider bar the other slider bar will also move in the same direction.
Cabin Pressure Control System (CPCS) - A 'Low Cabin' mode can be used for more comfort (cabin at lower pressure altitude) for flight up to intermediate cruise levels. Also, panoramic flights (frequent altitude changes) will be more comfortable using the 'Low Cab' mode, due to a constant rather than continuously adjusting cabin pressure.
During climb the cabin altitude is scheduled to achieve 8,000 feet when the aircraft reaches 30,000 feet.
During climb the cabin altitude is scheduled to achieve 10,000 feet when the aircraft reaches 30,000 feet.
The Crew Alerting System (CAS) window of the systems MFD displays a 'CABIN PRESSURE' red warning. What does it mean?
The Vapor Cycle Cooling System (VCCS) (when installed) is designed to operate on the ground from a 28 VDC ground power unit or aircraft electrical power when at least one generator is on.
The Vapor Cycle Cooling System (VCCS) (when installed) is designed to operate on the ground from a 28 VDC ground power unit or aircraft electrical power when both generators are on.