What does a dual generator failure lead to in terms of bus integrity?

A dual generator failure in an aircraft typically results in the loss of both the essential bus and the avionics 2 bus. In a well-designed electrical system, primary power is distributed across multiple busses to ensure redundancy and reliability. However, when both generators fail, the primary source of electrical power is compromised.

The essential bus is crucial for powering critical flight instruments and systems necessary for safe flight, while the avionics 2 bus supplies power to non-essential but important systems. Without the generators, these busses cannot be sustained, leading to their loss. Understanding this scenario is essential for pilots and maintenance personnel, as it highlights the importance of generator operations and the systems that depend on them for functionality.

In contrast, the other options suggest different consequences that do not accurately reflect the specific systems affected by a dual generator failure. Loss of all main buses implies a total power failure, which is not necessarily the case if auxiliary power sources are available, and complete avionics failure or power transfer to auxiliary systems may not occur immediately or specifically due to dual generator loss.