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39 Cards in this Set
- Front
- Back
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What two types of power does the Apu provide |
Pneumatic, shaft horsepower |
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What type of starter does the GTC P85 Apu use |
DC Electric, series type |
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At what engine speed will the starter disengage |
35% |
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Why does the starter stay engaged for as long as it does on this system |
Prevent excessive EGT |
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What type of compressor does this system use |
Centrifugal, two-stage compressor, first stage is double sided, double entry, second stage is single sided, single entry |
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What type of combustion section does this system use |
Single, side entry can type |
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What type of turbine does this system use |
Radial inflow |
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What type of lubrication system is used in the GTCP85 |
Dry-sump positive pressure |
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What limits oil system maximum pressure |
Adjustable relief valve |
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What may happen if the gear case vent becomes clogged |
There will be negative pressure inside the gear case |
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What happens if the oil filter becomes clogged |
Oil will bypass because of bypass valve |
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What are the three percentages of RPM which are significant to the sequencing device |
35%, 95%, 110% |
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What component sequences the starter cut out, arming of the low circuit and overspeed circuit |
3-speed switch / centrifugal switch |
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Define idol as a term related to the GTC P85 APU |
operated at rated speed with no load |
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On systems which use a load compressor what is this for |
Separates compressors |
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What component ensures that engine maintains its constant rated speed by varying fuel flow |
FCU or fuel control unit |
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What are the requirements to energize the ignition system |
Sufficient air to support combustion, minimum of 4 PSI oil pressure |
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Where does the fuel come from to feed the APU |
Aircraft main fuel tank |
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At what pressure is fuel bypassed to the fuel pump Inlet |
60 PSI |
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What component in the fuel circuit prevents excessive EGT during operations ( primarily starting) |
Acceleration limiter |
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What creates the greatest load on the system |
The pneumatic load |
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What type of fuel nozzle is used on the system |
Single duplex nozzle |
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What component in the pneumatic system prevents excessive EGT during operations |
Bleed valve which modulates automatically |
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What kind of engine would you classify the GTC P85 APU |
Centrifugal, turbo shaft |
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How is the bleed valve controlled and operated |
Electrically controlled, pneumatically operated |
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How do you perform a cool down before shutting the system down |
Apu to idle for shutdown is 1 to 3 minutes |
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When is the 110% circuit tested |
At engine shutdown |
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How do you start the gtcp 85 APU |
Follow the checklist, move the switch to on and everything else is automatic |
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What is the starter circuit powered by |
Powered by 28 volt battery or GPU |
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What type of impeller does the compressor first stage app |
Double sided, Double Entry type impeller |
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What component collects the combustion chamber of hot gases and directs them to the turbine nozzle diaphragm |
The Torus |
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From what chamber will we extract customer bleed air |
Plenum chamber |
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Where are the components like the starter, the generator, and the fuel pump mounted |
The accessory gearbox |
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How are large aircraft heated and cooled |
Air cycle machines |
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And what percent of RPM with a low circuit be arm |
95% |
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What is the first component in the air path of the APU |
Air Inlet plenum |
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What type of generator would generally be mounted on the APU |
Same type and rating as that found on the main engines |
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APUs are generally located where in the aircraft |
Near the tail section |
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What is used to cool the generator and oil on the APU |
Cooling fan |
