What does TCH refer to in instrument approaches?

Threshold Crossing Height (TCH) specifically refers to the vertical distance above the runway threshold at which an aircraft crosses while on an instrument approach. This measurement is essential for ensuring that the aircraft is at the appropriate altitude during the final stages of the approach, which provides pilots clear guidance for descent rates and landing configurations. Maintaining the correct TCH helps pilots ensure a safe and accurate approach to the runway, minimizing the risk of obstacles and ensuring compliance with approach criteria.

In the context of instrument approaches, understanding TCH is vital as it contributes to the overall safety and precision of landing operations. Knowing how to interpret and apply TCH data aids in achieving a stabilized approach path, which is crucial for instrument flying where visual references may be limited due to weather or other factors.