What is a "crosscheck" in the context of instrument flight?

In the context of instrument flight, a "crosscheck" refers specifically to the process of verifying instrument readings against one another to ensure they are accurate and consistent. This technique is crucial for maintaining situational awareness and safety during flight when relying on instruments rather than visual references.

For example, a pilot may compare readings from the altimeter, vertical speed indicator, and attitude indicator to confirm that they are in alignment and that the aircraft is performing as expected. By performing crosschecks, pilots can detect any discrepancies that may indicate instrument malfunction or situational errors, allowing them to make informed decisions based on the most reliable data available.

The importance of crosschecking cannot be overstated in instrument flight operations, where misinterpretation or reliance on a single instrument reading can lead to dangerous situations. Ensuring that different instruments corroborate each other provides a layer of safety and reliability in maintaining control and navigating the aircraft.