What does the term 'instrument cross-check' generally refer to?

The term 'instrument cross-check' refers to systematically checking instruments for coordinated information. This practice is crucial in instrument flying, as it helps pilots gather a comprehensive and accurate picture of their aircraft's performance and flight conditions.

In instrument flying, relying on a single instrument can be misleading due to instrument error or environmental factors. By cross-checking multiple instruments, pilots can validate the readings against one another, ensuring that they work together to provide a consistent view of altitude, airspeed, heading, and other critical flight data. This method promotes accuracy and enhances situational awareness, enabling pilots to make informed decisions and maintain safe flight operations even in challenging conditions such as low visibility.

The other options do not accurately capture the essence of instrument cross-checking. For instance, simply observing one instrument at a time overlooks the important interplay between different systems. Verifying instruments without a specific order may lead to oversight of potential discrepancies between readings. Finally, having multiple instruments show the same data at the same time does not imply a thorough cross-check; it is the systematic method of confirming and comparing various readings that ensures flight safety.