FSD International
Commander 115 TC
Pilot Operating Handbook
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Copyright© 2008 by FSD International. All rights reserved.
For use with Microsoft Flight Simulator only. Not to be used for real-world aviation.
MASTER SWITCHES
Two toggle switches control the electrical system and are located at the left end of the lower switch
panel. The left switch, labeled BAIT MASTER, controls battery power to the airplane. The right
switch, labeled ALT MASTER, controls alternator output.
For normal operations, both master switches should be ON. With the ALT MASTER turned OFF, the
entire electrical load is placed on the battery. Therefore, all non-essential electrical equipment
should be turned off and the flight should be terminated as soon as practical when operating with
the ALT switch OFF. Use the Emergency Gear Extension procedure when extending gear with the
alternator off.
VOLT/AMMETER
The panel mounted digital volt/ammeter will indicate current flow, in amperes, from the alternator
to the battery, or from the battery to the electrical system. With the engine operating and both the
battery and alternator master switches ON, the ammeter should indicate on the charge (+) side. In
the event of an alternator malfunction, or if the electrical load demand exceeds the alternator
output, the ammeter will indicate on the discharge (-) side. When the ammeter continues to
display on discharge side, electrical load must be reduced until ammeter indicates on charge side.
The volt/ammeter also allows the pilot to monitor bus voltage, and when used in conjunction with
the ammeter, provides an excellent indication for electrical system operation. When system is
operating normally, voltmeter will read between 24 and 30 volts, generally at approximately 28
volts.
A low voltage reading (less than 24 volts) or a slow decrease in the voltage reading, accompanied
by a very low charging reading on the ammeter, indicates the al '.ernator is becoming overloaded.
If this situation occurs, reduce the load by turning off non-essential equipment. Voltmeter reading
should return to normal (approximately 28 volts) and the ammeter reading should increase. If this
occurs, proceed with night, but use caution in increasing electrical load. A low voltage reading (less
than 12 volts) or a slowly decreasing voltmeter reading, accompanied by a discharge reading on
the ammeter, indicates the alternator is not on the line and the battery is carrying the entire load.
This situation will result in a complete loss of electrical power when the battery becomes
discharged. To correct the condition, immediately reduce the electrical load to the minimum
essential for safe operation. Place ALT master switch OFF and back to ON. If voltmeter reading
returns to normal (approximately 28 volts) and ammeter shows a charge, alternator is on the line
and operating normally. Place deactivated equipment back in operation, one unit at a time, while
monitoring voltmeter and ammeter for abnormal indications, and continue normal operation.
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If voltmeter reading does not return to normal and ammeter continues to show discharge, a fault
exists in the alternator system. Place ALT master switch OFF and prepare to terminate flight as
soon as practical.
It is essential to reduce the electrical load as much as possible prior to attempting to reset the
alternator. If an overload caused the alternator to drop off line initially, the alternator will not come
back on the line until the over load condition is corrected.
Heavy electrical usage~ such as prolonged cold weather engine starts or extended period •• of
ground operation, may reduce the battery charge enough for it to accept higher than normal
charging rates during the initial part of the flight. This will be indicated by higher than normal
ammeter readings. After reasonable period of time (approximately thirty minutes), ammeter
readings should return to normal. If high ammeter readings continue after this time period, there is
a possibility the battery may overheat and evaporate electrolyte at an excessive rate. To preclude
