A panel led by principal scientific adviser Ajay Kumar Sood has been assigned the task of resolving the contentious issue surrounding the rollout of 5G services near airports, considering concerns related to aircraft and passenger safety. According to senior officials familiar with the matter, a broader panel has been formed to address the “5G matter” as there was no consensus on timelines for replacing outdated aircraft radio altimeters—a crucial device that provides essential altitude information during landings in low visibility conditions. Discussions involving the Directorate General of Civil Aviation (DGCA), the Department of Telecommunications (DoT), telcos, airline operators, and aircraft manufacturers have been ongoing for over a year, with no resolution in sight.
In November 2022, the DoT directed mobile operators not to install any 5G sites in the 3,300-3,670 MHz band within 2.1 km of both ends of runways at all Indian airports to avoid potential interference with aircraft radio frequencies. This was intended as a temporary measure until altimeters of aircraft were replaced. Telecom operators have raised concerns about being barred from offering 5G services around airports, leading to revenue losses. In September, top Indian telcos urged the civil aviation ministry to press the DGCA for a deadline for all airlines operating in India to replace their absolute radio altimeter systems.
Boeing and Airbus suggested that altimeters must be replaced for a permanent solution around 5G connectivity at airports, and a decision needed to be made regarding purchase orders by airlines and the DGCA. The aircraft manufacturers indicated they could supply altimeters to countries outside the US only after December 2023. The situation has escalated as airlines are yet to place purchase orders. Preliminary estimates suggest around 500 Boeing aircraft and roughly 300 Airbus aircraft in India require a retrofit.
A radio altimeter typically functions in a bandwidth of 200 MHz in the frequency band 4200 MHz to 4400 MHz. Despite the guard band in between the two frequencies auctioned for 5G (3300-3670 MHz), concerns persist about interference due to the broader frequencies caught by the current altimeters in aircraft, which are outdated.
