During Emergency Descent Mode, how many degrees does the heading bug slew?

During Emergency Descent Mode, how many degrees does the heading bug slew?

• A. 90 degrees to the left.
• B. 45 degrees to the right.
• C. 180 degrees.
• D. 0 degrees.

Answer: (A)

In Emergency Descent Mode, the system uses a predefined initial maneuver to get the aircraft onto a safe descent path, and the heading bug on the attitude/HSI automatically moves to reflect that. It slews 90 degrees to the left to indicate the required initial left-hand turn. This gives the crew a clear, immediate cue of the direction and magnitude of the automatic guidance. The other options would imply no turn, a smaller turn to the right, or a full reversal, which don’t match the standard EDM behavior.

In Emergency Descent Mode, the system uses a predefined initial maneuver to get the aircraft onto a safe descent path, and the heading bug on the attitude/HSI automatically moves to reflect that. It slews 90 degrees to the left to indicate the required initial left-hand turn. This gives the crew a clear, immediate cue of the direction and magnitude of the automatic guidance. The other options would imply no turn, a smaller turn to the right, or a full reversal, which don’t match the standard EDM behavior.