How many annunciators are typically illuminated on the initial application of power?

Upon the initial application of power to the T-6A, it is common for a total of eight annunciators to illuminate. This occurs as part of the aircraft's self-check system, indicating that the different systems and components are undergoing a status check to ensure they are functioning properly.

The illumination of these annunciators at startup serves several important purposes. First, it provides a visual confirmation to the pilot that the electrical system is operational. Additionally, it allows for an early indication of any potential issues that may need attention before flight. This step is critical in ensuring the safety and reliability of the aircraft's systems prior to takeoff.

As for the other choices, they do not accurately reflect the typical number of annunciators that illuminate during the initial power application, which is firmly established as eight. Understanding this number is essential for pilots to recognize what to expect during pre-flight checks.