What the auto-restart function does do
It automatically tries to restart the engine quickly and restore the power setting that is being asked by the
transmitter. To trigger this function, the ECU checks:
•
The radio signal is valid, no failsafe condition.
•
The readings of the RPM are consistent with a flameout condition (the speed of the RPM
coasting down is between preset limits).
•
The readings of the exhaust temperature are consistent with a flameout condition.
•
The battery voltage is good.
•
No other faults detected.
Once the ECU is satisfied that the shutdown/flameout was most likely caused by an interruption of
combustion, usually caused by an air bubble, the ECU triggers the quick restart function, where the
ignitor is energized to full voltage and the pump is started at a power dependent of the current engine
status (RPM and EGT).
Once the ECU detects that the combustion has reassumed, the starter power is set to full power to reach
the idle rpm as quickly as possible, and the pump power is increased accordingly to the real RPM
increase, allowing for delays caused by bubbles arriving to the engine.
If after 10 seconds of restart the ECU doesn’t detect a stable combustion, the procedure is aborted and
the normal cooldown initiated.
What the AutoRestart function will not do
•
It will not restart the engine if the shutdown was caused by any fault other than a typical flame out
caused by air in the fuel system.
•
It will not monitor and confirm flight conditions are optimum for a restart. Leaving the restart to
progress is the pilot responsibility and decision, depending on each particular case.
When should AutoRestart function be enabled?
Auto-Restart is fast but still takes an average time of 10s to establish restored level of pre-shutdown
power. It is highly recommended that Auto-Restart only be used on airframes capable of sustaining
enough flight for the re-start to be completed. Some aircraft examples include: lightly loaded planes,
gliders, or multi engine planes.
It is highly advised that a shutdown simulation be done before selecting Auto-Restart option in the ECU
RADIO menu. Do it during a normal flight at a high altitude, throttle down to idle then begin a 10sec
count down. From this try to gauge if the aircraft can maintain controlled flight during this time at idle
setting.
If your plane cannot maintain flight for a minimum of 10sec without engine power, do not enable the Auto
Restart function.
“I’m flying my (turboprop) plane and the engine has shutdown with restart enabled, what should I
do”:
Think that the chances of that the engine restart are slim.
You don’t know why it has shut down, so
likely it will not restart, DO NOT RELY on it.
1.
Fly your plane.
Leave the throttle at mid setting and fly your plane keeping airspeed in aft for a
dead stick landing. Be ready for the sudden torque effect as prop power returns.
Page 49
