By Capt. Joe DePete, Opinion contributor
Commercial aviation is the safest mode of transportation in the world, and that didn’t happen by accident. As a nation, we made it a priority—and the Air Line Pilots Association, Int’l intends to keep it that way. Radio altimeters are key safety components found on all commercial airliners and are potentially susceptible to interference by 5G wireless systems. Last year, the FAA flagged safety concerns for the National Telecommunications and Information Administration, saying that “Harmful interference can interrupt or significantly degrade radar altimeter functions during critical phases of flight—precluding radar altimeter-based terrain alerts and low-visibility approach and landing operations.”
This interference with radio altimeters has been documented as a safety risk by others as well, and so the risk must be taken seriously. Those who evaluated the interference risk and drafted the findings back in 2020 did so under the auspices of RTCA, a nonpolitical globally recognized aviation standards body whose members include all major airframe and avionics systems manufacturers.
RTCA’s report has since been validated by the FAA and multiple aviation safety regulators globally and demonstrates that radio altimeter interference is a safety risk because the data generated onboard the aircraft is often utilized by its other systems. During an interference situation, the hazardous or misleading radio altimeter data may ultimately change the controllability of the aircraft at the worst possible time—during the approach and landing. It may also reduce or eliminate the functionality of terrain-avoidance systems.
The safety of our national airspace today has come from aggressive, proactive efforts to manage risks and ensure that at least two highly trained and qualified pilots operate all commercial airliners in the United States. Nearly every airline and thousands of other operators utilize risk-predictive data analysis to mitigate safety issues before they turn into incidents, accidents, and fatalities. Maintaining that high standard of safety is of paramount concern and aviation experts agree that the recent offer by Verizon and AT&T to place temporary restrictions on 5G transmissions simply do not provide enough protection for radar altimeters.
There are ways that 5G can be deployed while preserving aviation safety. While some point to the use of 5G in other countries, they neglect to mention that 5G signals in other parts of the world have been restricted in various ways compared to the US. Some countries allow 5G at reduced transmitting power or utilize other techniques such as pointing antennas below the horizon to ensure that radio altimeters do not experience interference. Canada recently proposed to simply restrict the subset of problematic 5G signals from being transmitted near airports, while allowing them to be used almost everywhere else.
Given the amount of test data needed to demonstrate the significant risks of interference, we cannot—and should not—wait for an in-flight interference event to be reported before working to resolve it. In other words, let’s not run the test on your flight to visit your family.
To ensure safety, the FAA recently announced that it will likely need to limit certain types of aircraft operations, meaning that cargo shippers and passengers will experience flight disruptions when these 5G signals go live. The FAA is taking this necessary action to ensure that safety is maintained, and we applaud them for it.
ALPA pilots continue to stand ready to roll up their sleeves and work to resolve the technical issues that need to be remedied before all 5G signals go live. As we have said since 2018, ALPA is prepared to work collaboratively with the wireless industry and the broader aviation community to ensure that every passenger and cargo flight arrives safely. However, our bottom line is crystal clear: there can be no retreat from the extraordinary safety record we have achieved here in America.
Capt. Joe DePete is the president of the Air Line Pilots Association, International.