What is the allowable airspeed tolerance for IFR operations?

For IFR operations, the allowable airspeed tolerance is +/- 10 knots. This standard is important as it ensures that pilots maintain a safe and controlled airspeed within specified limits during instrument flight. Adhering to this tolerance is crucial for safe operations, especially in conditions where precision flying is essential due to limited visibility or flying solely by instruments.

Maintaining airspeed within this tolerance helps pilots stay within the performance limits of the aircraft and also aids in compliance with air traffic control clearances. This standard is particularly relevant during approach and landing phases, where deviations in airspeed can significantly impact the aircraft's performance and handling characteristics.

Other airspeed tolerances, such as 5 or 15 knots, are not generally considered acceptable for IFR operations. A tolerance of 5 knots might be too tight to accommodate real-world variations in airspeed during flight, while a 15-knot tolerance could lead to safety concerns by allowing excessive deviations from the intended airspeed.