The airplane is not on the radar because it may be flying at a very low altitude, below the radar coverage area. Additionally, if the airplane's transponder is turned off or malfunctioning, it will not be detected by radar. Weather conditions such as heavy precipitation or storms can also interfere with radar signals, causing the airplane to not appear on the radar. **

There could be several reasons why an airplane is not showing up on radar. One possibility is that the aircraft's transponder, which transmits its identification and altitude information to air traffic control radar systems, may be malfunctioning or turned off. Additionally, the airplane may be flying at a very low altitude or in a location where radar coverage is limited or unavailable. Weather conditions such as heavy precipitation or atmospheric interference can also affect radar detection of aircraft. **

Yes, an airplane can disappear from radar if it flies low enough. Radar coverage is limited by the curvature of the Earth, so if an airplane flies at a very low altitude, it may not be within the radar's line of sight. Additionally, terrain and obstacles can block radar signals, causing the airplane to disappear from radar. This is why radar coverage is typically better over open water or flat terrain compared to mountainous or heavily forested areas. **

A military radar is a system used by the military to detect and track aircraft, missiles, ships, and other objects in the air or on the ground. It uses radio waves to determine the range, angle, and velocity of the objects it detects. Military radars are an essential tool for surveillance, early warning, and air defense, providing crucial information for military operations and national security. They can be deployed on land, at sea, or in the air, and are designed to operate in various environmental conditions and combat scenarios. **

You can listen to aircraft radio communication in the airplane by using a handheld aviation radio receiver. These devices are available for purchase and can pick up the radio transmissions between the aircraft and air traffic control. It's important to note that using a handheld radio receiver in an airplane may be subject to certain regulations and restrictions, so it's best to check with the airline and relevant authorities before attempting to do so. Additionally, some airlines may offer in-flight entertainment systems that allow passengers to listen in on the cockpit communications. **

It is unclear which airplane model you are referring to. Can you please provide more specific information or context so that I can accurately answer your question? Thank you. **

The choice between Flixbus and airplane depends on several factors such as cost, time, and convenience. Flixbus may be a more affordable option for budget travelers and offers the flexibility of multiple stops along the route. On the other hand, airplanes are faster and more convenient for long distances, especially for international travel. Additionally, airplanes may be the preferred choice for travelers with limited time or those who prioritize comfort and amenities. Ultimately, the decision between Flixbus and airplane will depend on individual preferences and travel needs. **

The distance from the radar installation to the airplane can be calculated using the formula: distance = (speed of light) * (time taken for the signal to be received) / 2. Since the speed of light is approximately 3 x 10^8 meters per second, the distance can be calculated as: distance = (3 x 10^8 m/s) * (500 s) / 2 = 7.5 x 10^10 meters. Therefore, the airplane is located approximately 75,000 kilometers away from the radar installation. **