What does the glide-path provided by PAPI indicate to pilots?

The glide-path provided by the Precision Approach Path Indicator (PAPI) serves as a crucial visual aid for pilots by indicating the correct descent angle to the runway during approach and landing. When pilots see the PAPI lights, they can determine whether they are on the correct glide slope by the color of the lights. Typically, a combination of red and white lights is displayed; for example, seeing two red and two white lights suggests that the aircraft is on the correct descent path. This information is vital for ensuring a safe and efficient approach to landing, helping pilots to maintain the appropriate altitude and angle as they approach the runway.

In the context of the other options, while level flight position, aircraft speed, and wind shear warnings are important considerations during flight operations, they are not indicated by the PAPI system. The PAPI specifically focuses on providing guidance related to the descent angle, which is essential for a safe landing.