Engine Limitations

Question 1

What is the MIN BATTERY voltage for engine start?

Answer 1

24V

Question 2

What timings must be observed for starter use and engine cooling during multiple attempts at engine start?

Answer 2

Start attempt 1 - Starter ON (30s), Cooling down (1 min)

Start attempt 2 - Starter ON (30s), Cooling down (1 min)

Start attempt 3 - Starter ON (30s), Cooling down (30 mins)

Question 3

What is the max Transient TRQ + for how long can it be at this value?

Answer 3

115%

10 sec

Question 4

What is the max T/O Power TRQ + how long can it be at this value?

Answer 4

111%

5 min at T/O (cumulative per sortie)

Question 5

What is the max Continuous TRQ?

Answer 5

92%

Question 6

What is the Max Engine Start TOT?

Answer 6

927 degrees

Max 10 sec between 810 and 927 degrees

Question 7

What is the max Transient TOT?

Answer 7

899 degrees

Max 6 sec over 810 degrees

Question 8

What is the max T/O Power TOT?

Answer 8

810 degrees

5 mins at T/O (cumulative per sortie)

Question 9

What is the max Continuous TOT?

Answer 9

752 degrees

Question 10

What is the max transient limit for Propeller RPM (N2) (15 sec max above 2132 N2)?

Answer 10

2233 N2

Question 11

What is the max continuous Propeller RPM (N2)?

Answer 11

2132 N2

Question 12

What is the max Propeller RPM (N2) for Static Ground ops with a crosswind component >10kts?

Answer 12

1850 N2

relevant to the prop overspeed governor check

Question 13

What is the N2 Speed Avoidance Range?

Answer 13

N2 stabilized for longer than 1 sec between 1523 RPM and 1786 RPM with more than 20% TRQ.

N2 must not be allowed to stabilize within the N2 speed avoidance range.

The speed avoidance range applies in both forward and reverse thrust.

Any accumulated time spend in the speed avoidance range must be recorded in the engine logbook.

Question 14

What is the max transient N1 (Gas Generator RPM)?

Answer 14

106%

max 15 sec > 105% N1

Question 15

What is the max continuous N1?

Answer 15

105% N1

Question 16

What is the max transient Oil Pressure?

Answer 16

Cold Weather = 150psi

Engine Start = BETA RANGE

Question 17

What is the max oil pressure?

Answer 17

Cold Weather = 130psi

Engine Start = BETA RANGE

Question 18

What is the MIN oil pressure when N1 >= 94%?

Answer 18

Cold Weather = 120psi

Engine Start = 105psi

NOTE - Min permitted oil pressure DECREASES LINEARLY by 2psi per 1000ft ABOVE 5000ft PRESSURE ALTITUDE to a max reduction of 20psi.

Question 19

What is the MIN oil pressure when N1 = 85% to 94%?

Answer 19

Cold Weather = 90psi

Engine Start = 75psi

Question 20

What is the MIN oil pressure when N1 < 85%?

Answer 20

Cold Weather = 50psi

Engine Start = 35psi

Question 21

How much does min permitted oil pressure decrease for each 1000ft above 5000ft PresAlt and what is the max reduction?

Answer 21

2psi per 1000ft above 5000ft PresAlt

Max reduction = 20psi

Question 22

What is the engine oil temperature Max limit at TRQ < 40%?

Answer 22

107 degrees

Question 23

What is the engine oil temperature Max Transient limit at TRQ >= 40% + for how long can it remain above the max continuous temp and below this max transient temp?

Answer 23

107 degrees

5 mins between 82 and 107 degrees

Question 24

What is the engine oil temperature Max Continuous limit at TRQ >= 40%?

Answer 24

82 degrees

Question 25

What is the min oil temp?

Answer 25

0 degrees

Question 26

What is the min oil temp before starting?

Answer 26

-40 degrees