TM 55-1520-240-T 4-6.3 POWER TURBINE CONTROL SYSTEM (N2) OPERATIONAL CHECK 4-6.3 INITIAL SETUP References: Applicable Configurations: TM 55-1520-240-23 Without  74 Equipment Condition: Tools: TM 55-1520-240-23: None Battery Connected Materials: Electrical Power On None Hydraulic Power On Thrust Control at Detent Position Personnel Required: Visual Check of Power Turbine Control System Per- Medium Helicopter Repairer formed (Task 4-6.2) Aircraft Powerplant Repairer TASK RESULT CHECK CIRCUIT BREAKERS 1. Check that ENGINE NO. 1 TRIM and TRIM & TIMER If either circuit breaker (1 or 2) is open, close it.  It circuit circuit breakers (1 and 2) are closed. breaker (1) opens again, go to task 4-6.4.  If circuit breaker (2) opens again, go to task 4-6.5. 2. Check that NO. 1 EMERG ENG TRIM circuit breaker If circuit breaker (3) is open, close it.  If it opens again, go (3) is closed. to task 4-6.6. 3. Check that  ENGINE NO. 2 TRIM and TRIM & TIMER If either circuit breaker (4 or 5) is open, close it.  If circuit circuit breakers (4 and 5) are closed. breaker (4) opens again, go to task 4-6.7.  If circuit breaker (5) opens again, go to task 4-6.8. 4. Check that NO. 2 EMERG ENG TRIM circuit breaker If circuit breaker (6) is open, close it.  If it opens again, go (6) is closed.   to task 4-6.9. CHECK NORMAL POWER TURBINE CONTROL SYSTEM 4.1  Set and hold pilot NO. 1 ENGINE BEEP TRIM switch No. 1 engine fuel control pointer (8) shall be between  19 (7) to RPM DECREASE for 30 seconds.  Check NO. 1 and 21 on protractor (10).  If it is not, go to task 4-6.22. engine fuel control pointer (8). TASK RESULT 5. Set and hold pilot's NO. 1 ENGINE BEEP TRIM switch No. 1 engine fuel control pointer (8) shall move toward the (7) to RPM INCREASE for 30 seconds. clockwise mechanical stop (9).  If pointer does not move, go to task 4-6.10. 6. Set and hold pilot's NO. 1 ENGINE BEEP TRIM switch No. 1 engine fuel control pointer (8) shall move and stop (7) to RPM DECREASE for 30 seconds. between  19 and 21 on protractor (10).  If pointer does not move or moves but stops outside of  19 to 21 on protractor, go to task 4-6.11. 6.1  Set and hold pilot NO. 1 & 2 ENGINE BEEP TRIM No. 2 engine fuel control pointer (8) shall be between  19 switch (11) to RPM DECREASE for  30 seconds.  Check and 21 on protractor (10).  If it is not, go to task 4-6.23. No. 2 engine fuel control pointer (8). 7. Set and hold pilot's NO. 1 & 2 ENGINE BEEP TRIM No. 2 engine fuel control pointer (8) shall move toward the switch (11) to RPM INCREASE for  30 seconds. clockwise mechanical stop (9).  If No. 2 pointer does not move, go to task 4-6.12. 8. Set and hold pilot's NO. 1 & 2 ENGINE BEEP TRIM No. 2 engine fuel control pointer (8) shall move to and switch (11) to RPM DECREASE for  30 seconds. stop between 19 and 21 on protractor (10).  If No. 2 pointer does not move or moves but stops outside of  19 to 21 on protractor, go to task 4-6.13. 9. Set and hold copilot's thrust control NO. 1 ENGINE No. 1 engine fuel control pointer (8) shall move to BEEP TRIM switch (7) to RPM INCREASE for  30 clockwise mechanical stop (9).  If pointer does not move, seconds. go to task 4-6.14. 10.   Set and hold copilot's NO. 1 ENGINE BEEP TRIM No. 1 engine fuel control pointer (8) shall move and stop switch (7) to RPM DECREASE for 30 seconds. between  19 and 21 on protractor (10).  If pointer does not move, go to task 4-6.15. 11.   Set and hold copilot's NO. 1 & 2 ENGINE BEEP TRIM No. 2 engine fuel control pointer (8) shall move to switch (11) to RPM INCREASE for  30 seconds. clockwise mechanical stop (9).  If No. 2 pointer does not move, go to task 4-6.16. 12.   Set and hold copilot's NO. 1 & 2 ENGINE BEEP TRIM No. 2 engine fuel control pointer (8) shall move to and switch (11) to RPM DECREASE for  30 seconds. stop between 19 and 21 on protractor (10).  If No. 2 pointer does not move, go to task 4-6.17. 13.   Set and hold copilot's NO. 1 & 2 ENGINE BEEP TRIM No. 1 and No. 2 Fuel control pointers (8) shall move switch (11) to RPM INCREASE for  30 seconds. toward the clockwise mechanical stop (9).  If pointer contacts stop, go to step 15.  If pointer does not contact stop, go to step 14. GO TO NEXT PAGE 4-120  Change 17