APU TEST QUESTIONS AND ANSWES
Minimum lbs of fuel to operate and what tank? - Answers - 1000 lbs minimum for first
hour, 500 lbs every hour after. Left tank
What altitude can the APU operate at? - Answers - 43,100 ft
What is the starting duty cycle? - Answers - 3 start attempts in 60 minutes
When does the run light illuminate? - Answers - At 95%
EGT limits? - Answers - 716 no load, 663 with load
Within how many seconds does the intake open? - Answers - 115 seconds
When does the starter disengage? - Answers - 50% (below 24,000 ft)
What percent does the fuel solenoid valve open? - Answers - At 7%
If load, how long is the cool down cycle? - Answers - 100 seconds
-100% for 15 seconds
-82% for 85 seconds
What DC voltage must the main battery and APU battery have to start the APU? -
Answers - 28v DC
What's the minimum amount of times you should do the APU starting and operation
procedure a month? - Answers - Once
If operating APU with the APU access doors open, why must you have an observer near
the APU compartment? - Answers - To look for a fire
What's the over speed percent for the APU? - Answers - 106%
How long does the inlet door stay open? - Answers - 15%
What percent rpm does the ignition auto relight kick on? - Answers - 96.5%
How many feet away from building to operate with the apu exhaust? - Answers - 32.8
feet (10 meters)
During the cool-down cycle, the air intake door and APU fuel shutoff valve must close in
approximately how many seconds? - Answers - 60 seconds
What are the emergency procedure steps for when you are inside the cockpit? -
Answers - -Push manual override button, and pull APU fire handle
Minimum lbs of fuel to operate and what tank? - Answers - 1000 lbs minimum for first
hour, 500 lbs every hour after. Left tank
What altitude can the APU operate at? - Answers - 43,100 ft
What is the starting duty cycle? - Answers - 3 start attempts in 60 minutes
When does the run light illuminate? - Answers - At 95%
EGT limits? - Answers - 716 no load, 663 with load
Within how many seconds does the intake open? - Answers - 115 seconds
When does the starter disengage? - Answers - 50% (below 24,000 ft)
What percent does the fuel solenoid valve open? - Answers - At 7%
If load, how long is the cool down cycle? - Answers - 100 seconds
-100% for 15 seconds
-82% for 85 seconds
What DC voltage must the main battery and APU battery have to start the APU? -
Answers - 28v DC
What's the minimum amount of times you should do the APU starting and operation
procedure a month? - Answers - Once
If operating APU with the APU access doors open, why must you have an observer near
the APU compartment? - Answers - To look for a fire
What's the over speed percent for the APU? - Answers - 106%
How long does the inlet door stay open? - Answers - 15%
What percent rpm does the ignition auto relight kick on? - Answers - 96.5%
How many feet away from building to operate with the apu exhaust? - Answers - 32.8
feet (10 meters)
During the cool-down cycle, the air intake door and APU fuel shutoff valve must close in
approximately how many seconds? - Answers - 60 seconds
What are the emergency procedure steps for when you are inside the cockpit? -
Answers - -Push manual override button, and pull APU fire handle
