What is the designated indicator for the standby airspeed indicators in each cockpit?

The standby airspeed indicator, often abbreviated as the standby ASI, is specifically designed to serve as a backup to the primary and secondary airspeed indicators in the cockpit. Its primary function is to provide critical airspeed information in the event that the main indicators fail, ensuring that pilots have access to vital flight data at all times.

This system is essential for maintaining safety during flight, especially if there are instrument malfunctions. The standby airspeed indicator is usually placed in a position that allows for quick reference, typically visible to the pilot alongside other important flight instruments.

In contrast, the other indicators mentioned, such as the primary and secondary airspeed indicators, serve different purposes, with the primary airspeed indicator being the main source for airspeed data, and the secondary indicator providing additional or supplementary information. The flight speed monitor, while it may have relevance in specific contexts, is not a standardized term in aviation for airspeed measurement and does not denote the function of providing immediate backup airspeed information like the standby airspeed indicator does.