What is VAT/VREF in aviation?

VAT, or VREF, refers to the velocity reference speed at threshold in aviation. This is a critical speed that pilots need to know during the landing phase of flight. It is essentially the minimum speed at which an aircraft can safely land on the runway while still maintaining control. This speed is calculated based on specific parameters, including the weight of the aircraft and the flap configuration used during the landing.

Understanding VREF is essential for ensuring a safe landing, as it helps pilots avoid stalling the aircraft by ensuring that they are sufficiently above the stall speed at the threshold of landing. It also aids in determining the correct approach speed, which is fundamental in executing a stable and safe landing.

Since VREF is directly related to the aircraft's performance, it takes into account various factors such as wind conditions and aircraft configuration, thus ensuring optimal safety and efficiency during approach and landing.