Most air travelers are familiar with the pre-flight announcement requiring passengers to switch their phones to flight mode, also known as airplane mode. This mode severs the phone's connection to cellular networks, rendering passengers unable to make calls or use social media during the flight. However, many people are not aware of the underlying reasons for this requirement.

One key reason for activating airplane mode during a flight is to prevent signal interference. When a phone is in airplane mode, it cannot emit radio signals of any kind. Radio signals have the potential to cause electromagnetic interference in aircraft systems, electronics, or communications, which could jeopardize pilot or navigational systems. This issue is more prevalent in older aircraft, as newer models are designed to withstand such interference.

Another important reason to use airplane mode while flying is to safeguard ground equipment. Using a mobile device at altitude can pass through multiple network towers, disrupting the frequencies of ground-based equipment. This disruption can lead to increased cell tower activity and adversely affect ground-based devices.

Moreover, activating airplane mode, especially before and during takeoff and landing, helps prevent passengers from being distracted by their devices. Reduced distractions can enhance passengers' awareness of their surroundings and enable them to make more informed decisions in case of an emergency.