At which range of airspeed are Pitot-static system errors generally greatest?

The correct choice indicates that Pitot-static system errors are generally greatest at low airspeeds. This is primarily because at lower speeds, the dynamic pressure that the Pitot tube measures becomes significantly weaker. The Pitot-static system relies on the difference between static pressure and total pressure to determine airspeed. At low airspeeds, small errors in static pressure readings can lead to proportionally larger errors in indicated airspeed.

Additionally, at low airspeeds, the aircraft is more susceptible to variations in airflow around the Pitot tube, which can cause inaccuracies due to factors such as turbulence or obstructions in the airflow path. The higher relative influence of these small errors on the overall reading at lower speeds makes this range critical for accurate measurements.

In contrast, at high airspeeds, the effects of dynamic pressure become more pronounced, allowing the system to function more accurately; thus, errors tend to be less significant. Similarly, medium airspeeds fall between these two extremes, experiencing more stable and reliable readings than at low speeds. Consequently, the impact of static and Pitot pressure discrepancies is minimized. Understanding this characteristic of the Pitot-static system helps pilots maintain accurate airspeed readings, especially during critical phases of flight like takeoff and landing.