PART I - DESCRIPTIVE
(iii)The starter master switch (65) and circuit breaker
(83). These complete the circuit through the starter
button, ignition switch and relight switch. When the
relight switch is at RELIGHT the starter button is
isolated. The starter master switch also controls the
electrical supply to the engine instruments, and com-
pletes the circuits to No 2 inverter and the booster-
pumps. The switch should be ON and the circuit
breaker in at all times when the engine is running.
(iv)The starter pushbutton (64), which initiates the start-
ing sequence.
(c) When the pushbutton is pressed the starting cycle is
initiated. For the first two to three seconds the starter
motor combustion chamber is purged by air under
pressure. Then fuel is fed to the chamber where it is
ignited and causes the motor to turn the engine com-
pressor. At the same time the engine high energy igniter
units operate to ignite the fuel spray in the engine com-
bustion chambers. After approximately 7-10 seconds the
engine becomes self sustaining and as the starter motor
reaches its top speed, a switch operates to shut down the
liquid starting system. The engine should then accelerate
to the normal idling r.p.m. of 2,500.
(d) Should the starter fuel fail to light up, a pressure sensitive
switch in the starter fuel line operates to cut off the
starter system.
(e) It is important that personnel keep clear of the starter
exhaust during starting. The exhaust is aft of the engine
starter access door beneath the fuselage.
14. Relighting system
A RELIGHT switch (31) is situated on the port shelf,
and when held to RELIGHT for two seconds completes
the circuit, through a time delay switch, to the high
energy ignition units. The ignition then operates auto-
matically for 30 seconds. The switch is spring-loaded
to return to the off position.
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