iNDICA NEWS BUREAU-
For the past 2-odd years the aviation industry has been terribly affected, mainly due to the pandemic aside. However, that has not been the only issue troubling the industry.
The next generation 5G technology has been causing airborne concerns for the aviation industry in the US.
Concerned over 5G transmissions interfering with aircraft ‘radio altimeters’, the US aviation regulator has issued directives that impose severe operational restrictions on aircraft flying close to 5G wireless ground transmission stations.
Among the impacted airlines would be Air India, the only Indian carrier that operates to the US. It also operates these routes with US-manufactured aircraft and so would come under the ambit of these directives.
In India, 5G testing is on and air safety experts say these shouldn’t be carried out near airports or areas where aircraft descend low.
For the aviation industry, the big problem maker is the 5G C-band transmissions with spectral closeness to radio altimeter (RA). Radio altimeter is the only sensor onboard an aircraft that provides information on aircraft height above terrain and other obstacles.
Its accurate altitude readings are used by a number of aircraft systems, including collision avoidance systems and ‘Autoland’ functions, all of which play critical roles, especially after the aircraft descends below 2,500 feet for an approach and landing.
During low-visibility landings, the RA readings’ constant feed on aircraft height clearance over ground help cockpit crew gain situational awareness.
The 4200-4400 MHz band is a shared band internationally reserved solely for radio altimeters.
“Any failures or interruptions to these sensors can therefore lead to incidents with catastrophic outcomes, potentially resulting in multiple fatalities,” said a document on 5G interference released by International Air Transport Association last year.
Capt Amit Singh, an air safety expert said: “In India, 5G deployment isn’t imminent. But from an air safety point of view, testing is the same thing as deployment because the 5G waves would be transmitted in locations where the testing is on. But here, the relevant stakeholders such as airport operators, civil aviation regulators, airlines, pilots aren’t aware of these 5G waves. That is more dangerous because inadvertently something might happen. NOTAMs (notice) should be issued for pilots. Ministries should come together to form directives to ensure that 5G testing takes place at a safe distance from the airport. The idea is no surprises.” On November 25, a mobile service provider conducted 5G tests in Kolkata, on October 5, testing happened in Delhi, he added.
To prevent the interference of 5G transmissions with RA, aircraft manufacturers Boeing and Airbus developed an ‘Aviation Safety Proposal’ which seeks to limit cellular transmissions.
However, in the US, that proposal hasn’t been accepted yet, which was why the US regulator came up a directive restricting aircraft operations, especially in low-visibility conditions.
“About 3.45 lakh passenger flights, 32 million passengers, and 5,400 cargo flights will be impacted in the form of delayed flights, diversions or cancellations if the US regulator’s air-worthiness directive is implemented,” said Airbus and Boeing in a joint letter sent this week to the US transportation secretary.
The letter sought the postponement of 5G roll-out in the US, scheduled for Jan 5, 2022.