Power Plant Flashcards
What engine is the Bell 505 power plant?
Safran Arrius 2R.
How many double-thermocouples provide temperature sensing in the engine?
Four.
How many MGT signals are fed to each ECU channel?
Two.
What caption would you expect to see if one of the MGT signals is declared failed by the ECU, and what is the action required?
- White ECU MAINT caption.
- Maintenance required prior to next flight.
What caption is triggered when both of the MGT signals are declared failed by the ECU?
A yellow ECU DEGRADED caption.
At what NG is the engine typically self-sustaining?
50% NG.
When is the electrical supply to the starter cut off?
At engine self-sustaining speed.
Where is MGT measured?
Gas generator turbine outlet.
How is torque measured?
Load through the helical teeth on the intermediate gear cause causes the torquemeter piston to change the value of modulated pressure supplied to the torque transmitter.
What caption would you expect if the torque signal was declared failed by the ECU?
A yellow ECU DEGRADED caption.
How is NP measured?
Two magnetic sensors located on the forward gearbox at the NP intermediate gear shaft.
What caption would you expect if one of the NP signals is declared failed by the ECU?
A yellow NP SENSOR FAIL caption.
What caption would you expect if both NP signals were declared failed by the ECU?
A red ECU FAIL caption.
What is the meaning of the white ECU DATA caption?
ECU data input to the Integrated Avionics Unit has failed.
What are the two functions of the NG alternator (the PMA)?
- Primary source of electrical power to the ECU.
- Provides NG acquisition signal.
What caption would you expect if one of the NG acquisition signals fails?
A white ECU MAINT caption.
What caption would you expect to see if both NG acquisition signals are declared failed while during start or at idle power?
A red ECU FAIL caption.
What two things happen if both NG acquisition signals are declared failed while in-flight?
- The ECU reverts to an alternate law.
- A yellow ECU DEGRADED caption shows.
Below what engine oil pressure will the red ENG OIL PSI LOW caption appear?
25psi.
Above what engine oil pressure will the yellow ENG OIL PSI HI caption appear?
217psi.
From what material is the engine compressor wheel made?
Titanium
What type of compressor does the engine have?
Single-stage centrifugal
What is the compression ratio of the engine compressor?
9:1
At what Ng is the engine considered to be self-sustaining?
50%
How is Np measured?
A phonic wheel in the accessory gearbox with two magnetic speed sensors.