TM 55-1520-240-T
8-6.3
TORQUE INDICATING SYSTEM OPERATIONAL CHECK (Continued)
8-6.3
TASK
1.
Check that ENGINE NO. 1 AC TORQUE circuit
breaker (1) is closed.
2.
Check that ENGINE NO. 1 DC TORQUE circuit
breaker (2) is closed.
3.
Check that ENGINE NO. 2 AC TORQUE circuit
breaker (3) is closed.
4.
Check that ENGINE NO. 2 DC TORQUE circuit
breaker (4) is closed.
5.
Check No. 2 pointer on pilot (5) and copilot (6)
torque indicators.
NOTE
If pointer is spinning, have helper
manually
turn
rotor
blades
until
spinning stops. If spinning continues
after one revolution of the blades, go to
next step.
6.
Check No. 1 pointer on pilot (5) and copilot (6) torque
indicators.
NOTE
If pointer is spinning, have helper
manually
turn
rotor
blades
until
spinning stops. If spinning continues
after one revolution of blades, go to
next step.
NOTE
If torque signal simulator LTCT 24137-
03 is not available, do not perform
steps 7 thru 10. Go to step 11.
7.
Install torque signal simulator LTCT 24137-03 on
No. 1 engine. Reference operating manual 5855A.
8.
Check No. 1 engine torque indication using torque
signal
simulator LTCT 24137-03.
Reference
operating manual 5855A.
9.
Install torque signal simulator LTCT 24137-03 on
No. 2 engine. Reference operating manual 5855A.
10. Check No. 2 engine torque indication using torque
signal
simulator LTCT 24137-03.
Reference
operating manual 5855A.
11. Have pilot start both engines and stabilize rotors at
ground idle.
12. Have
pilot
perform
TORQUE
DIFFERENTIAL
CHECK. (Ref TM 55-1520-240-MTF.)
RESULT
If ENGINE NO. 1 AC TORQUE circuit breaker (1) is open,
close it. If it opens again, go to task 8-6.4.
If ENGINE NO. 1 DC TORQUE circuit breaker (2) is open,
close it. If it opens again, go to task 8-6.5.
If ENGINE NO. 2 AC TORQUE circuit breaker (3) is open,
close it. If it opens again, go to task 8-6.4.
If ENGINE NO. 2 DC TORQUE circuit breaker (4) is open,
close it. If it opens again, go to task 8-6.5.
No. 2 pointer on both torque indicators (5 and 6) shall be
below 10%. If not, adjust torque indicator to zero. (Ref
TM 55-1520-240-23.)
No. 1 pointer on both torque indicators (5 and 6) shall be
below 10%. If not, adjust torque indicator to zero. (Ref
TM 55-1520-240-23.)
No. 1 pointer on pilots and copilots torque indicators (5
and 6) shall read 2% of simulator selector switch value.
If it does not, go to task 8-6.8.
No. 2 pointer on pilots and copilots torque indicators (5
and 6) shall read 2% of simulator selector switch value.
If it does not, go to task 8-6.9.
TASK
13. Check No. 1 and No. 2 pointers on pilot and copilot
torque indicators (5 and 6).
14. Have pilot shut down both engines.
FOLLOW-ON MAINTENANCE:
TM 55-1520-240-23:
Battery disconnected.
Electrical power off.
Hydraulic power off.
RESULT
No. 1 pointer on both torque indicators (5 and 6) shall
indicate required torque. If not, go to task 8-6.6.
If No. 1 pointer on both torque indicators (5 and 6) rotates
clockwise or counterclockwise continuously, replace No.
1 engine torquemeter kit (junction box, output shaft, and
head assembly). Ref TM 55-2840-254-23.
If No. 1 pointer on both torque indicators (5 and 6)
operates erratically, go to task 8-6.10 if Lycoming On Wing
Comparator LTCT 28295-01 is available. If it is not, go to
task 8-6.6.
No. 2 pointer on both torque indicators (5 and 6) shall
indicate required torque, if not, go to task 8-6.7.
If No. 2 pointer on both torque indicators (5 and 6) rotates
continuously, replace No. 2 engine torquemeter kit
(junction box, output shaft and head assembly). Ref
TM 55-2840-254-23.
If No. 2 pointer on both torque indicators (5 and 6)
operates erratically, go to task 8-6.11 if Lycoming On Wing
Comparator LTCT 28295-01 is available. If it is not, go to
task 8-6.7.
END-OF-TASK
Change 19 8-106.1
