This. And also, the article claims: > Commercial flights typically fly CAT II or CAT III approaches. That's not true at all. We fly by far the most CAT I appr

This. And also, the article claims: > Commercial flights typically fly CAT II or CAT III approaches. That's not true at all. We fly by far the most CAT I approaches, or visual with the navigation instruments only as a backup. To be allowed do a CAT II or CAT III approach, the ground environment needs to be managed differently by air traffic control. They will monitor and keep completely empty a big area around the ILS transmitters and the runway. Specifically to avoid any interference with the signals. Not even official airport cars are allowed in while doing CAT II or III operations. So anyone that would want to transmit something nefarious would be standing in an empty grass and asphalt area that is actively monitored by ATC.