While the risk of interference with aircraft systems is minimal, not putting your phone on airplane mode during a flight can lead to faster battery drain and potential annoyance for pilots and air traffic controllers. Airplane mode disconnects your device from cellular networks while still allowing you to use it and even connect to in-flight Wi-Fi in many cases.
While the risk of interference with aircraft systems from mobile phones is generally low, there are potential concerns that justify the continued use of airplane mode during flights. Studies have shown that active radio transmitters like mobile phones can theoretically interfere with aircraft electronics, particularly GPS receivers which are crucial for safe landings1. In 2014, U.S. government officials revealed that passenger cellphones could interfere with display units on certain Boeing 737 and 777 aircraft models2. The Federal Aviation Administration (FAA) issued an airworthiness directive requiring airlines to replace vulnerable display units to "prevent loss of flight-critical information displayed to the flightcrew during a critical phase of flight"2. However, the risk is considered low, as evidenced by the FAA allowing a 60-month compliance timeframe for the directive2. Experts note that the problem is cumulative - the greater the number of active phones, the higher the potential for interference with flight systems2. While individual phones may not pose a significant threat, the collective use of signal-emitting devices by multiple passengers could potentially impact aircraft electronics.
When phones are not in airplane mode during flights, they can cause significant disruption to ground-based cellular networks. As the plane moves at high speeds, phones constantly attempt to connect to multiple cell towers, rapidly switching connections. This behavior can overload ground networks, potentially affecting service quality for users on the ground. The Federal Communications Commission (FCC) cites this as a primary reason for maintaining airplane mode regulations, as the cell towers are designed for static communities rather than fast-moving aircraft passengers2. Additionally, phones increase their signal strength to maintain connections with distant towers, leading to accelerated battery drain14. This constant searching and switching between towers not only impacts the phone's performance but also puts unnecessary strain on the cellular infrastructure.
Failing to enable airplane mode on your phone during a flight can significantly impact battery life and device performance. The constant search for cellular signals in an environment with limited connectivity causes rapid battery drain, with users reporting losses of up to 30-40% overnight even in airplane mode15. This issue is exacerbated when airplane mode is not activated, as the device continuously increases its signal strength to maintain connections with distant towers2. Additionally, background processes and location services may continue running, further depleting the battery1. To mitigate these effects, users are advised to not only enable airplane mode but also manage background app refresh and location services settings to minimize unnecessary power consumption during flights14.
Failing to put your phone in airplane mode can potentially interfere with the aircraft's communication systems. Cell phones emit electromagnetic signals that may disrupt the plane's radio communications and navigation equipment.1 These signals can cause cross-talk or adjacent-channel interference, potentially compromising clear communications between pilots and ground control.2 While modern aircraft are designed with shielding to protect against such interference, the cumulative effect of multiple active devices on board could still pose a risk. The Federal Aviation Administration (FAA) and Federal Communications Commission (FCC) ban the use of cellular connections during flights specifically due to these potential safety concerns.1 Additionally, as airlines transition to 5G technology, there are heightened worries about interference with radio altimeters, which are crucial for measuring the aircraft's distance from the ground, especially during landing in low visibility conditions.2