General
ROTORCRAFT FLIGHT MANUAL
MD 500E
(Model 369E)
CSP
−
E
−
1
Revision 14
1
−
12
1
−
13. AUTO REIGNITION SYSTEM
The automatic reignition system provides automatic actuation of the ignition
exciter in the event that power is lost as a result of engine flameout.
The system senses signals from the engine power out warning unit and con-
sists of a indicator light (RE IGN P RST) on the instrument panel, a RE−IGN
test switch, and the necessary electrical components and wiring to connect the
system. Power is supplied through the ENG OUT circuit breaker and the sys-
tem is armed by M/R transmission oil pressure.
Each time that an ENGINE OUT/low rotor warning is activated, the RE IGN
P RST caution light will illuminate, showing that the ignition exciter has been
energized. This light will remain ON until manually reset after N
1
and N
R
in-
crease back above the values (55% N
1
/468 N
R
) that activate the ENGINE OUT/
low rotor warning.
On Aircraft equipped with the original (‘‘pre−generic’’) electrical system the ig-
nitor will stop firing once the N
1
and N
R
increase above 55% N
1
/468 N
R
.
On aircraft equipped with a generic wire harness style electrical system, the
ignitor will also continue to fire until the RE IGN P RST caution light is reset.
NOTE
:
In the event of a N
R
or N
1
tach generator failure, the RE IGN P RST caution light
will illuminate and the continuous duty ignition exciter will remain energized until
the engine is shut down or the auto reignition system is disarmed. The reignition
system is armed under all operating conditions.
Following any activation of the automatic reignition system as a result of
flameout due to snow, ice, or water ingestion, inspect the engine in accordance
with the appropriate Allison Operation and Maintenance Manual.
Yawing of the helicopter may or may not follow an engine flameout and reigni-
tion sequence. Magnitude of the yaw will depend on forward speed and power
being used.
Failure or deactivation of the ENGINE OUT/low rotor waring system, renders
the reignition system inoperative.
