Technology tangle: On 5G services and flight disruptions

• Air India and several other airlines have cancelled flights to the US.
• They are worried the 5G roll-out there may affect aircraft and passenger safety, a concern raised by Boeing and Airbus in the past.

5G and flight safety

• Airlines take off and land using auto-pilot systems, which use data from radar altimeters to determine the altitude of the aircraft.
• Altimeters emit radio waves at 4.2-4.3 Gigahertz (GHz) frequency, which could interfere with a 5G band called C-Band, which lies between 3.7-4.4 GHz.
• This interference can mess up the data which causes the safety concern.
• Radio altimeters are used at airports and other low-altitude locations.
• A different kind of altimeter, called pressure altimeter, is used for high altitude areas.
• Not using auto-pilot would lead to more fuel consumption and higher costs for airlines.

What happens to Air India’s operations?

• While scheduled international flights, to and from India, remain suspended due to the pandemic, Air India operates flights to the US under an air bubble agreement.
• The Indian carrier operates flights to Chicago, Washington, San Fransisco, New York, and Newark, among other locations.
• These routes are served by the airline’s wide-body fleet of Boeing 777 and Boeing 787 planes.
• The roll out of 5G is expected to primarily impact the operations of Boeing 777 and 747.
• The Federal Aviation Admin-istration (FAA) has asked Boeing 787 operators to take “additional precautions” when landing on wet runways at affected airports.

Way forward

• US  regulators,  aware  of  the problem since at least 2018, left about a 200 MHz buffer between the altimeters’ frequency and the 5G C-Band frequency.
• The worry is that some older radio altimeters, like in the Boeing 777, may still find it difficult to work under that headroom, and the exact number of such altimeters in commercial aircraft are not known.
• This is the reason why some US telcos have temporarily deferred the 5G roll-out and the FAA will conduct tests at airports where C-Band 5G will be operational to find a solution.

Can this impact India’s 5G roll-out?

• India’s 5G auctions are expected to include spectrum bands of 3.3GHz -3.6GHz, which means the C-Band may not be operational, at least in the near future.
• Plus, aircraft equipment is manufactured globally, with certain standards.
• The FAA tests will likely lead to standards for altimeters and applied internationally.
• For aircraft makers, altimeters are a key equipment.
• But they’re bought off-the-rack instead being designed in-house.
• Once a standard is known, it can be implemented in all aircraft.