Engines and Related Systems Flashcards
How many sections is the engine divided into?
4
Hot
Cold
Accessory
Power Turbine
What is included in the cold section?
Inlet particle separator, the compressor, the output shaft and line replaceable units
How many stages does the compressor have?
6, 5 axial and 1 centrifugal
How many subassemblies are there in the hot section?
3
Gas generator turbine
Stage 1 nozzle assembly
Combustion liner
What sections does the power turbine have?
Two stage power turbine, exhaust frame, shaft and C sump assembly
What does the accessory section include?
accessory gear box, HMU, engine driven boost pump, oil filter, oil cooler, oil pressure sensor, fuel pressure sensor
What makes up the engine fuel system supply?
boost pump, fuel filter, fuel filter bypass, fuel pressure sensor, ODV
What are the two mechanical inputs from the cockpit to the HMU?
Load demand spindle and Power available spindle
What does the load demand spindle do?
Provides mechanical input from the collective output to the HMU to reduce transient engine and NR droop.
What does the sheer pin/roll pin in the LDS provide?
It prevents flight control jam in the event of a load demand malfunction. The pin will sheer causing the LDS to the HMU to drive fully aft and produce the most demand, may present as a torque split
What operates the Power Available Spindle in the HUM?
The engine power control levers
What does the ODV do?
Sends fuel to the fuel manifold for starting, acceleration, and engine operations.
It purges fuel
It will shut of fuel flow to prevent engine overspeed and hot starts
What does the engine alternator supply?
AC power to the ignition excited, DEC/EDECU, NG signal to the cockpit
What do the two bleed airports provide?
Cabin heating and air for crossbleed starts
What do the 2 sensors on the exhaust frame provide?
Power turbine governor and tachometer signal to DEC/EDEC
What does appearance of the INLET ANTI ICE advisory indicate above 13*C?
indicates a system malfunction
What does the failure of the INLET ANTI ICE advisory below 4*C indicate?
System malfunction, do not fly the aircraft in known icing
Due to engine bleed limits, what Q levels will inhibit inlet anti icing?
10% Q
When will you see the ENG 1 OIL PRESS or ENG 2 OIL PRESS caution?
22 PSI or below
What is the capacity of the oil tank?
7 qts
How is oil cooled?
It passes through the oil cooler and transfers its heat to fuel. It then passes through scroll vanes, further cooling the oil and preparing the anti-ice system
What are the 3 pneumatic sources for engine starts?
APU, crossbleed, ground source
When should the engine starter on caution disappear?
Cutoff speed of 52-65% NG
When will fuel flow automatically shut off?
If TGT reaches 900*C
Can you start the engine with the ignition off?
No, but you can motor it
What bias does the DEC incorporate?
-112*C
What signals does the DEC provide to the cockpit?
NP1/NP2, Q, TGT
What does hot start prevention do?
Prevents over temp during engine start or shut down
When does HSP activate?
When NG < 60%, NP < 50%, TGT>900*C
When does the DEC command the HMU to limit fuel?
Dual engine: 10 minute, 879*C +/- 9
Single engine: 2.5 minute, 903 +/- 10
When will the DEC switch to contingency power?
When the opposite Q is less than 50% (engine failure or torque split)
When is the NP overspeed protection tripped?
NP 120% +/- 1
How do you know you have an EDECU installed?
25 on the TQ code
For an engine with an EDECU, when will you get contignecy power?
NP drops below 96%
Greater than 3% droop between the reference and actual NP
Greater than 5% per second NP droop rate
When will NG display on the power pod?
Either engine NG exceeds 100%
Difference between NG 1 and NG 2 is 5%
Either engine is out
When does TGT display on the power pod?
Either engine exceeds 793C
Difference between TGT 1 and TGT 2 is greater than 75C
Either engine is out
What happens when the DCU miscompares?
The parameter that has miscompared will turn black with a yellow background
