What essential altitude information is needed to calculate holding speeds during an approach?

To calculate holding speeds during an approach, essential altitude information includes altitude thresholds. Holding speeds are generally determined based on the aircraft's weight, but the specific altitude at which these speeds are applicable can vary. Altitude thresholds provide critical parameters for pilots to establish the correct airspeed while managing their aircraft in a holding pattern.

These thresholds correspond to various altitudes where specific holding speeds apply, ensuring safe and efficient operation. Different altitudes can lead to different speed requirements according to regulations and performance charts. By understanding these altitude thresholds, pilots can accurately calculate and maintain the necessary holding speeds, which is vital for maintaining safe separation and managing delays effectively during approach and landing phases.