TM 55-1520-240-23-3
4-5
CHECK ENGINE COASTDOWN TIME
4-5
INITIAL SETUP
Applicable Configurations:
All
Tools:
Stopwatch
Materials:
None
Personnel Required:
Inspector
Army Rotary Wing Aviator
References:
TM 55-1520-240-10
TM 55-2840-254-23 Without 74
TM 1-2840-265-23 With 74
Equipment Condition:
Battery Connected (Task 1-39)
Engine Work Platform Open (Task 2-2)
Engine Access Cover Open (Task 4-49)
NOTE
Procedure is same to check
coastdown time on No. 1 or No. 2
engine.
1.
Have pilot operate engine until PTIT and oil
temperature has stabilized (TM 55-1520-240-10).
2.
Set ENGINE CONDITION lever to GROUND.
3.
After engine rpm has stabilized, set ENGINE
CONDITION lever to STOP.
4.
Watch N1 indicator and check time required to
reach 0 rpm. If coastdown time is more than
25 seconds, go to Follow-On Maintenance. If
coastdown time is less than 25 seconds, go to
step 5.
5.
Inspect chip detectors (TM 55-2840-254-23
without 74 , TM 1-2840-265-23 with 74 ).
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