Air India on Wednesday announced the cancellation of eight flights to the US amid a global scramble by airlines to reschedule flights following concern that the rollout of 5G services in the country could potentially interfere with aircraft navigation systems.
Air India tweeted that it would not operate eight flights on the Delhi-Chicago, Delhi-New York, and Delhi-San Francisco sectors due to the deployment of 5G communications in the US. Apart from Air India, Delta Airlines and American Airlines operate direct flights between India and the US at present.
The Indian Express reported that the Directorate General of Civil Aviation is already coordinating on the issue with Indian carriers. The concern stems from a US Federal Aviation Administration warning on January 14 that the new 5G technology, being rolled out from Wednesday, could interfere with in-flight instruments such as radar altimeters.
Altimeters measure an airplane’s height above the ground. Radar altimeters operate in a frequency range between 4.2 and 4.4 GHz and aviation authorities and airlines are concerned that the mid-range frequencies auctioned in the US are close to this band. In 2021, the US auctioned 5G bandwidth to telecom companies in the 3.7-3.98 GHz spectrum range called the C-band.
C-band spectrum use for 5G technology has concerned the aviation industry across the world. Aviation regulatory bodies and airlines have argued that if the frequencies of commercial 5G were close to the frequency of the airwaves used by wide-body aeroplane instruments, it could disturb readings.
In the US, the proximity of the two frequency bands is particularly close. In most regions and countries such as the European Union, most telecom companies deploy 5G in the 3.4-3.8 GHz band. In South Korea, 5G spectrum operates in the 3.42-3.7 GHz band. These frequencies are lower than the US’s mid-band frequency of 3.7-3.98 GHz range.
The issue seems to particularly impact the wide-body Boeing 777 used for long-haul operations.
Dubai-based Emirates has already announced halting of flights to Chicago, Boston, Houston, Dallas-Fort Worth, Newark, Miami, Florida, New Jersey, Orlando, Seattle, and San Francisco. Emirates cited the cancellation as necessary due to operational concerns over the planned deployment of 5G mobile network services at certain US airports.
Japan’s All Nippon Airways said the US Federal Aviation Administration had indicated that radio waves from the 5G wireless service could interfere with altimeters, The Indian Express reported. It added that Boeing had announced flight restrictions on airlines operating the Boeing 777 aircraft and the airline cancelled or changed the aircraft for some flights to and from the US based on the announcement.
The carrier has cancelled 20 flights to Chicago, New York, and Los Angeles. Air India also uses Boeing 777s on US routes.
The cancellations come despite carriers Verizon and AT&T said they would postpone the 5G service’s launch near some US airports.
In the telecom sector, a higher spectrum frequency typically means better service. Industry experts told The Indian Express that there were chances of the two bands interfering as service operators push operations to the highest possible band to extract the full value of 5G and give customers the best experience. Similarly, altimeters need to operate at higher frequencies to get accurate readings.
In India, which is yet to roll out 5G, the frequency range has been pegged around 3.3-3.68 GHz. The Indian Express reported that the Federation of Indian Pilots had expressed concern with the Department of Telecommunications about the frequencies being close.
The telecom department assured the pilots that there would be no interference as commercial 5G services would use frequencies at least 530 MHz away from those used for altimeters, a government official told The Indian Express. The Department of Telecommunications has also found support from the Cellular Operators’ Association of India, which said commercial 5G and aviation could co-exist safely.
SOME FLIGHTS RESUME
Air India resumed six flights on the Boeing 777 aircraft today after a clearance from Boeing.
The US Federal Aviation Administration has also issued a fresh directive and said altimeters in certain types of aircraft, including the Boeing 777, would not be affected by 5G services. An Air India spokesperson told the Press Trust of India that Boeing had cleared it to operate the B777 aircraft to the US.