TM 55-1510-220-MTF
PROCEDURE
TROUBLESHOOTING
REFERENCE
b.
Autofeather switch - Hold to TEST (ARM lights should remain extinguished).
c.
Power levers - Advance to approximately 22% torque, then move autofeather switch to test mode.
Both ARM lights should illuminate.
d.
Left power lever - Retard.
(1) At 16 to 21% torque, check right AUTOFEATHER light extinguished.
(2) At 9 to 14% torque, check left AUTOFEATHER light extinguished (left propeller starts to feather).
e.
Left power lever - Set approximately 22% torque.
f.
Repeat steps b, c, and d for right engine.
g.
Advance each power lever to above 85 to 90% N1 individually, with the autofeather switch in the arm
mode. ARM lights should not illuminate. With both power levers above 85 to 90% NI, both ARM lights
should illuminate.
h.
Retard left power lever below 85% N1 Both lights should extinguish.
i.
Repeat step h by retarding right power lever, with left power lever above 85 to 90% N1.
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