"Confirm 3000 feet or 3000 meters?"
Metric Conversion Table for pilot reference to be inserted into FCU
In the modern aviation context, altitudes are generally referred in feet. However, there are some exceptions in the world, such as the People's Republic of China, Russia, and North Korea, which use the Metric system (i.e. Meters) for altitude measurement. To cater to the needs of airlines operating in those regions, the METRIC ALT push button enables pilots to have an additional altitude indication in meters (inside the Primary Flight Display). It is important to note that pilots do not fly directly referring to the metric display, but instead use conversion cards to obtain relevant FCU settings in Feet. Altitudes in feet remain the primary means of vertical navigation, while the meter display serves as a cross-checking reference.