The blackout at FIR Athens is not related to interference or malicious action by third parties, the commander of the National Cybersecurity Authority and MIT Media Lab researcher Michalis Bletsas, attributing the problem to a widespread telecommunications system failure.

“We know very well what happened. What we don’t know yet is how it happened,” he told ERTnews. “There was no interference. At the same time, that investigation into the causes is ongoing to determine how a similar incident can be prevented in the future.

The problem that grounded the planes last Sunday was due to remote control transmitters in the broadcast centers used for ground-to-air voice communication. “To a large extent, many transmitters were left on, some without sound and some emitting bomb or broadband noise,” he explained.

According to the commander of the National Cybersecurity Authority, this resulted in a takeover of frequencies, causing a “denial of service”. “When many transmitters are continuously transmitting on the same frequency, it cannot be used,” he noted, explaining that the backup system could not work when the spectrum is occupied. “Parallel spectrum, unfortunately, does not exist.”

Asked whether there was a risk to flight safety, he replied in the negative: “There was a question of great inconvenience to passengers, with flight cancellations, but in no case was there a safety problem,” he said, dismissing reports of “blind flights” as unsubstantiated.

No interference, no sabotage

Bletsas was clear on the issue of external interference, noting that there was none. “We must be unequivocal: the system’s own transmitters took over the spectrum. There was no external interference,” he said. Regarding scenarios of sabotage or foreign involvement, he clarified that “as far as we can see, it is not the result of malicious action.” As he said, the possibilities remain open, but “the scenarios diminish as the days go by.” At the same time, he suggested that the problem may be due to human technical error.

Speaking about the investigations being carried out, he said that members of the National Cyber Security Authority are gathering more evidence. Referring to why a new committee was convened and not the NMSC, he explained that this was done for speed and completeness, as many relevant agencies are involved.

Bletsas also pointed out that such incidents are not a Greek peculiarity, as similar failures have led to the closure of larger FIRs internationally in the past. “All systems fail at some point. The point is that the failures should not have a major impact and the systems should be resilient,” he said.

Even modern systems, he noted, have ways of failing, particularly as their complexity increases. “Never having failures is impossible,” he concluded.