What is the typical operating voltage of a 28V DC aircraft electrical system?

The typical operating voltage of a 28V DC aircraft electrical system is indeed 28 volts. This voltage level is standard in many modern aircraft systems, as it provides a good balance between efficiency and safety for electrical components.

Using 28 volts helps to ensure that the system can supply adequate power to avionics, lighting, and other electrical devices while minimizing weight and conductivity losses. This voltage is especially advantageous in systems where weight is a critical factor, as it allows for smaller and lighter wiring compared to higher voltage systems. Furthermore, aircraft electrical systems designed around 28V can effectively utilize widely available components and support a range of operational demands within the airframe.

Higher or lower voltages, such as the options of 12, 24, or 48 volts, might not meet the operational and safety requirements that modern aircraft demand. While some smaller aircraft may use 12V or 24V systems, 28V has been standardized in larger and more complex aircraft applications for these reasons.