What happens to the Flap Position Indicator when the AC BUS SHED annunciator is on?

When the AC BUS SHED annunciator is illuminated, it indicates that there is a loss of power from the AC bus due to a bus shedding condition. In this scenario, systems that rely on the AC electrical distribution, including the Flap Position Indicator, will lose power. This means that the indicator will no longer function or provide any visual feedback regarding the position of the flaps.

In a typical aircraft configuration, critical systems and indicators are powered by the AC bus. If the bus experiences a failure or is intentionally shed to conserve power for essential systems, non-essential systems lose their power source, resulting in a loss of functionality. The Flap Position Indicator, being one of those systems, will therefore not operate as expected.

The other answers do not accurately reflect the situation because the indicator does not become operational, malfunction, or simply illuminate without the necessary power being supplied to it. Hence, the correct understanding hinges on recognizing that the loss of power due to the AC BUS SHED condition is the primary reason for the Flap Position Indicator's incapacitation.