CSP-HE/HS-1
Optional Equipment
Automatic Engine Reignition
ROTORCRAFT FLIGHT MANUAL
MD 500
(Models 369HE/HS/HM
)
Revision 6
9-51
FAA Approved
9-15. OPERATING INSTRUCTIONS: AUTOMATIC REIGNITION
PART I
GENERAL
The Automatic Engine Reignition Kit provides automatic reignition of the
en−
gine in the event that power is lost as a result of engine flameout. There are
three versions of this kit: an early system (250−C18 only), a later unmodified
system (250−C18 or 250−C20 engine) and a later modified system (250−C18 or
250−C20 engine).
Early system (250−C18 only):
The system consists of a pressure switch in the engine compartment sensing
engine torque pressure, a guarded arming
switch and two indicator lights on
the instrument panel in the
cockpit, plus the necessary electrical compo−
nents and wiring
to connect the system.
When the system is armed by means of the cockpit switch,
the ARMED in−
dicator light is illuminated. Engine torque
pressure less than approximately
25 psi will close the
pressure switch illuminating the RE−IGN indicator
light in
the cockpit and energizing the engine ignition exciter to
reignite the
engine.
Later unmodified System (250−C18 or C20):
The system consists of a modification to the Engine Failure/
Low Rotor
Speed Warning sensing unit, a guarded arming
switch and two indicator
lights on the instrument panel in
the cockpit, plus the necessary electrical
components and
wiring to connect the system.
When the system is armed by means of the cockpit switch,
the ARMED in−
dicator light is illuminated. Main rotor speed
less than 98%
or N
1
speed
less than 55%, depending on the
throttle position, will illuminate the RE−
IGN indicator light
in the cockpit and energize the engine ignition exciter to
reignite the engine.
Later, modified system (250−C18 or C20):
This system consists of a modification to the Engine Failure/Low Rotor
RPM warning sensing unit, a test switch and two indicator lights on the
instrument panel plus the necessary electrical components and wiring to
connect the system.
Whenever there is transmission oil pressure, the
ARMED
indicator is illu−
minated. Rotor speeds less than 98
±
1 percent N
2
or N
1
speeds below 55
percent the
RE−IGN
indicator and energize the ignition exciter.
