India orders upgrades by 2027 to shield aircraft from 5G, 6G signal risk

Ever found your mobile phone's signal to be patchy while waiting for a flight? That’s because telecom operators can’t provide stronger signals near airports, as these can interfere with a small cockpit tool—a radio altimeter.The electronic gauge, which measures the altitude of an airborne plane, feeds data to multiple automated systems on board. A wrong reading can be a safety risk, especially during poor visibility.

But the restrictions have sparked concerns as telecom operators expand 5G coverage and prepare for even stronger 6G networks.Now, the civil aviation regulator has asked all airlines to modify the altimeters so that they are tolerant to 3,300-3,670MHz C-band—a key range of spectrum to provide 5G services, according to the Director General of Civil Aviation (DGCA) order dated 19 November 2025. Mint has reviewed a copy of the order.The required modification or retrofitting must be completed by 31 December 2027, the order said.India is not alone in facing this challenge.

Countries such as the US and those in Europe have faced similar challenges, with regulators proposing deadlines extending to 2029–2032 for full fleet retrofits. But that has also caused a spike in demand.

According to estimates by the American regulator Federal Aviation Administration (FAA), upgrades will cost around $4.5 billion for the US fleet alone.To be sure, the US had earlier addressed 5G interference concerns by requiring upgrades to aircraft radio altimeters, setting a February 2024 deadline. It later said the entire airline fleet had completed these upgrades by September 2023, mitigating immediate risks.