What effect does rain have on a windscreen during flight?

The phenomenon of rain impacting the visibility through a windscreen during flight primarily results in a deterioration of visibility. Rain droplets can distort the view ahead and create a blurred vision of the external environment. This can produce an optical illusion, leading a pilot to misjudge their altitude and distance from the ground or other objects.

In conditions of rain, the perception of flying higher and further away arises due to the way droplets can refract light, creating misleading visual cues. By obscuring and distorting the view, the rain creates a scenario where pilots may feel they are at a greater altitude than they actually are. The surrounding terrain and horizon become less distinguishable, contributing to this altered perception.

The presence of rain influences the pilot's ability to perceive their actual height and distance relative to the ground, which is critical for safe flight operations. Understanding this effect is vital for pilots as it directly affects their situational awareness and navigation tasks during adverse weather conditions.