APU Limitations

Question 1

Maximum APU EGT on start

Answer 1

1250 degrees C

Question 2

Maximum APU EGT continuous

Answer 2

650 degrees C

Question 3

Minimum APU battery voltage for start

Answer 3

23.5 volts?

Question 4

Minimum temperature for APU battery start

Answer 4

• 15 degrees C

Question 5

Maximum altitude for APU start

Answer 5

41,450’ ?

Question 6

Maximum altitude for APU start in elec emer configuration

Answer 6

FL200

Question 7

Max altitude for APU to supply electrical load

Answer 7

41,450’

Question 8

Maximum altitude for APU to supply electrics, bleed air ON & 1 A/C pack

Answer 8

22,500’

Question 9

Maximum altitude for APU to supply electrics, bleed air ON & 2 A/C packs

Answer 9

17,500’

Question 10

Maximum APU generator load

Answer 10

115kva

Question 11

Maximum APU rpm

Answer 11

107%

Question 12

Maximum APU starter duty cycle limit

Answer 12

After 3rd attempt, 60 min cooling (2 attempts on taxi in & leave for engineers?)

Question 13

Maximum APU altitude for Eng start assist

Answer 13

20,000’

Question 14

Elec emer consequences for APU

Answer 14

APU fuel pump loses power once land recovery selelcted.
If APU not up & running, will not start