Which bus is designed to stay powered to support critical flight instruments during abnormal conditions?

Which bus is designed to stay powered to support critical flight instruments during abnormal conditions?

• A. Avionics bus
• B. Lighting bus
• C. Essential bus
• D. Secondary bus

Answer: (C)

The key idea is that power to the most critical flight instruments is maintained by the essential bus during abnormal conditions. This bus is wired to supply essential flight instruments and related systems even when normal power is lost or when other electrical buses are shed to conserve energy. Avionics and navigation gear are typically on the avionics bus, which may not remain energized in an emergency if normal power is lost. The lighting bus is for cockpit and exterior lighting and isn’t critical for flight safety during abnormal conditions. The secondary bus carries nonessential or noncritical systems and isn’t designed to stay powered when power is limited. So, the essential bus is the one designed to stay powered to support critical flight instruments when conditions are abnormal.

The key idea is that power to the most critical flight instruments is maintained by the essential bus during abnormal conditions. This bus is wired to supply essential flight instruments and related systems even when normal power is lost or when other electrical buses are shed to conserve energy.

Avionics and navigation gear are typically on the avionics bus, which may not remain energized in an emergency if normal power is lost. The lighting bus is for cockpit and exterior lighting and isn’t critical for flight safety during abnormal conditions. The secondary bus carries nonessential or noncritical systems and isn’t designed to stay powered when power is limited.

So, the essential bus is the one designed to stay powered to support critical flight instruments when conditions are abnormal.