Visual Observations: Pilots are trained to visually scan the sky, looking for other aircraft in their vicinity. They utilize a combination of techniques such as systematic scanning, focusing on different areas of the sky, and using their peripheral vision to increase the chances of spotting other aircraft.
Markings and Lights: Aircraft are equipped with various lights and markings that enhance their visibility. These include navigation lights (red, green, and white lights on the wingtips and tail), anti-collision lights (strobe lights), and beacon lights. These lights make aircraft more visible, especially during low light conditions or nighttime operations.