How does the pilot change the barometric setting to STD?

How does the pilot change the barometric setting to STD?

• A. Turn the BARO knob
• B. Press the BARO set knob
• C. Push the STD button
• D. Dial in MCDU

Answer: (B)

Switching to STD changes the altimeter reference from local QNH to standard pressure, which is 1013 hPa (29.92 inHg). On the A320, you do this by pressing the BARO SET pushbutton on the barometric reference control. Rotating the BARO knob adjusts the QNH value, but pressing the BARO SET knob applies the standard pressure to the altimeters. The MCDU isn’t used to set STD, and there isn’t a separate STD entry through it. This STD setting is used above the transition altitude or whenever standard pressure is required for ATC procedures, ensuring all altitude readouts are aligned to the same reference.

Switching to STD changes the altimeter reference from local QNH to standard pressure, which is 1013 hPa (29.92 inHg). On the A320, you do this by pressing the BARO SET pushbutton on the barometric reference control. Rotating the BARO knob adjusts the QNH value, but pressing the BARO SET knob applies the standard pressure to the altimeters. The MCDU isn’t used to set STD, and there isn’t a separate STD entry through it. This STD setting is used above the transition altitude or whenever standard pressure is required for ATC procedures, ensuring all altitude readouts are aligned to the same reference.