TM 55-1520-240-T
4-10.4 ENGINE START AND IGNITION SYSTEM OPERATIONAL CHECK
4-10.4
INITIAL SETUP
References:
Applicable Configurations:
TM 55-1520-240-10
With 74
TM 55-1520-240-23
Tools:
Equipment Condition:
Aircraft Mechanic's Tool Kit,
TM 55-1520-240-23:
NSN 5180-00-323-4692
Battery Connected
Materials:
Electrical Power On
None
Hydraulic Power On
Engine Start and Ignition System Visual Check
Personnel Required:
Medium Helicopter Repairer
Army Rotary Wing Aviator (2)
TASK
RESULT
1.
Check that FADEC NO. 1 START & IGN circuit breaker
If START & IGN circuit breaker (1) is open, close it. If it
(1) is closed.
opens again, go to task 4-10.5.
2.
Check that FADEC NO. 2 START & IGN circuit breaker
If START & IGN circuit breaker (2) is open, close it. If it
(2) is closed.
opens again, go to task 4-10.6.
3.
On FADEC panel (3), check ENG 1 and ENG 2 switches If switches are not at PRI, set switches to PRI.
(4 and 5) are at PRI.
4.
Move ENGINE CONDITION NO. 1 and NO. 2 levers (6
If display shows 88, go to step 5. If display is blank or
and 7) to GND. Look at DECU NO. 1 and NO. 2 (8 and
other than 88, go to task 4-12.4.
9) fault display (10).
5.
Move ENGINE CONDITION levers (6 and 7) to STOP.
START NO. 1 ENGINE
CAUTION
If the No. 1 engine is the first engine started, start the No. 2 engine within 3 minutes.
6.
Have pilot start No. 1 engine. Monitor engine N1, ENG
N1 indication accelerates to 10% with ENG START switch
TEMP, OIL PRESS, and N2.
(11) at 1. At that point, pilot releases ENG START switch
and N1 indication increases and stabilizes at 50 to 59%
within 45 seconds. Engine OIL PRESS should be 20 psi
minimum.
If No. 1 engine N1 does not indicate 10%, go to task
4-10.7.
If No. 1 engine does not start or accelerate to 50 to 59%
N1, go to task 4-10.8.
If engine has high PTIT or hot start, go to task 4-8.2.
TASK
RESULT
If engine OIL PRESS is not 20 psi minimum, go to task
8-3.3.
7.
Have pilot stop No. 1 engine if no further checks are to be
performed.
8.
Move ENGINE CONDITION NO. 1 lever (6) to GND.
If display shows 88, go to step 9. If display is blank or
Look at DECU NO. 1 (8) fault display (10).
other than 88, go to task 4-12.4.
9.
Move ENGINE CONDITION NO. 1 lever (6) to STOP.
START NO. 2 ENGINE
CAUTION
If the No. 2 engine is the first engine started, start the No. 1 engine within 3 minutes.
10.
Have pilot start No. 2 engine. Monitor engine N1, ENG
N1 indication accelerates to 10% with ENG START switch
TEMP, OIL PRESS, and N2.
(11) at 2. At that point, pilot releases ENG START switch
and N1 indication increases and stabilizes at 50 to 59%
within 45 seconds. Engine OIL PRESS should be 20 psi
minimum.
If No. 2 engine N1 does not indicate 10%, go to
task 4-10.11.
If No. 2 engine does not start or accelerate to 50 to 59%
N1, go to task 4-10.12.
If engine has high PTIT or hot start, go to task 4-8.4.
If engine OIL PRESS is not 20 psi minimum, go to
task 8-3.3.
11.
Have pilot stop No. 2 engine if no further checks are to be
performed.
12.
Move ENGINE CONDITION NO. 2 lever (7) to GND.
If display shows 88, go to step 13. If display is blank or
Look at DECU NO. 2 (9) fault display (10).
other than 88, go to task 4-12.4.
13.
Move ENGINE CONDITION NO. 2 lever (7) to STOP.
FOLLOW-ON MAINTENANCE:
TM 55-1520-240-23:
Hydraulic power off.
Electrical power off.
Battery disconnected.
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4-226 Change 17
