At what voltage will the EADI and EHSI go offline when the bus tie is closed?

The EADI (Electronic Attitude Director Indicator) and EHSI (Electronic Horizontal Situation Indicator) are critical systems within an aircraft's avionics suite. Their functionality relies heavily on a stable power supply, which is typically provided through a bus system. When the bus tie is closed, both systems draw power from the same source, creating a situation where voltage levels become critical for ensuring operational integrity.

The correct voltage at which the EADI and EHSI will go offline when the bus tie is closed is 22 volts. This threshold is significant because it represents the minimum operational voltage required for these systems to function correctly. If the voltage drops below this level, the systems will automatically disconnect to prevent damage and maintain safety protocols. Normally, avionics are designed to operate efficiently within a certain range of voltages, and dropping below the specified 22 volts serves as a protective measure.

Maintaining awareness of this voltage threshold is crucial for pilots and maintenance personnel as it helps in assessing the health of the electrical systems on board. In practical terms, if the voltage level is monitored and observed to be approaching or dropping below 22 volts, immediate corrective actions may be necessary to restore electrical stability and ensure that critical navigation systems remain operational.