Final answer:
Emergency AC power on an aircraft is available via the emergency generator, static inverters, and the batteries. All these components are essential for ensuring power is supplied during emergencies. They contribute to safe operations when the main power systems are compromised.
Step-by-step explanation:
In flight, emergency AC power is available using various sources. The correct answer is (D) All of the above, which include the emergency generator, the static inverters, and the batteries. Each of these components plays a crucial role in providing power under emergency conditions.
The emergency generator (converts other sources of power into electrical) is usually driven by the aircraft's engines or a small dedicated turbine to produce electrical power if the main generators fail. Static inverters are devices that convert direct current (DC) from the batteries to alternating current (AC), allowing for the operation of AC equipment when the main generators are offline. The batteries themselves provide DC power, which can be used directly or inverted to AC power when needed.
When considering the utilization of power sources like solar panels and batteries for storage, these are generally inefficient for directly powering aircraft in flight, as seen in Box 17.1 discussing electric airplanes. Instead, they serve as emergency backups or potential sources of power in smaller, less power-intensive applications on aircraft.