Recently CDT completed a foreign apron installation project. The installation diagram is as follows:
The PAPI system is used to guide aircraft to approach the runway at an appropriate altitude.
The upper half of PAPI's beam is white and red in the lower half. In the visual range, different elevation lights in PAPI systems allow the aircraft to see different colors at different altitudes. The
pilot can judge and adjust the height of the plane by seeing the color of the beam, making it at the right height. When the pilot saw the white means to fly too high; when the pilot saw white and red together said height at the right moment; when the pilot saw the red light said flying too low, could hit obstacles.
If your project needs to install PAPI, please check the specific considerations and cautions.The website is https://www.cdt-en.com/helipad-lighting/Airport-Heliport-PAPI-Lights-204.html