Why it’s so difficult to contain the wave of bombing threats in Europe

A spate of bomb threats against airliners this week have forced diversions, emergency landings and military escorts in European airspace, fueling fear among passengers and increasing pressure on airlines.

Officials have described more than 20 threats as malicious hoaxes, and no actual attacks have taken place. But the latest incident highlights how even false claims can have a major impact on a tightly scheduled airline network.

“This is really unusual. I’ve never seen anything like this in my career,” Wilfried Covent, head of aviation security firm Covent Consulting, told CNBC by phone.

“There have been bomb threats on planes and at airports, but usually there’s one copycat, one or two at most. What we’re seeing now is a coordinated attack on airlines and airports.”

An email sent to European broadcasters on Friday claimed to be from the leader of the group behind the plane hoax, and also said a bomb had been planted in the building, prompting an evacuation. No bomb was found at the scene.

“What happened this week is just a glimpse of what awaits Europe in the near future,” the message said, according to Reuters.

The news agency said it could not confirm the identity of the sender, the origin of the email or whether it was related to the threat against the flight.

Covent said the “criminals” (who many security analysts have said are likely state-sponsored actors working in concert to disrupt European public life, but have not been identified) were well aware that “aviation’s greatest weakness is targeting aircraft in flight.”

“In the case of a threat to an airport or a general threat to aircraft, we can assess the situation without completely disrupting operations,” he told CNBC. “If a threat is called out with a specific flight number on a flight, international regulations are triggered that say it cannot be ignored, even if it’s a hoax. That means a quick landing, evacuation and search by specialized forces.”

“In the context of the evaluation, we can’t say the previous 20 times were hoaxes, so this one is a hoax as well. The safety of passengers and crew is paramount. The criminals know that.”

Responsibility for combating disinformation attacks is shared, international organizations told CNBC. Assessing security threats and implementing aviation safety measures is primarily the responsibility of national authorities, working in coordination with airport operators, airlines, and law enforcement agencies.

Air traffic control is also involved in finding aircraft with suitable landing spots, while the European Union Aviation Safety Agency (EASA) and the UK Civil Aviation Authority set broader aviation safety regulations that govern how airlines prepare their crews to respond to safety threats. Within the European Union, the European Commission is responsible for aviation security policy and coordination among member states.

Operational decisions also depend on where the threat occurs. Joji Waites, director of flight safety, policy and regulation at the British Airline Pilots Association, said airline assessors grade threats as red, amber or green, but an amber verdict would not be given if the aircraft was in flight.

If the evaluator determines the threat is credible, the crew is notified and the captain directs decisions regarding the aircraft based on company procedures. On the ground that might mean evacuation, but in the air the priority is to land as quickly and safely as possible.

In addition to fear and confusion about a particular flight, each diversion can impact the next flight scheduled to use that aircraft, crew hours, and connecting passengers.

Network effects can be significant. Philip Boehm, a visiting professor of aviation security at Coventry University, told the AP that a single diversion can cost an airline as much as $250,000, including crew changes, delayed connections and disrupted schedules for the rest of the day.

“The diversions required by these bomb threats disrupt a system designed for predictability and efficiency, leading to increased workload for pilots, air traffic controllers and airports,” an EASA spokesperson said in an emailed comment.

“The immediate security threat from individual disinformation threats is low, as all of these staff are trained to deal with unexpected developments like this. However, as the number of diversions increases, it puts additional strain on the system.”

John Edwards, a senior consultant at Gates Aviation in London, said by phone that governments are already considering regulations and frameworks for aviation authorities, and discussions will take place at a European and global level.

“Bomb threats against aviation have been going on for decades, but we need to look at what’s different. Why are there so many of them, and why are so many of them considered credible enough to warrant legitimate action?”

“There are a variety of questions that need to be addressed fairly quickly to establish a high-level level of confidence. If there are any new characteristics, every time this type of event occurs, it triggers a large-scale collaboration to ensure that it doesn’t happen again in the future.”

“In theory, the vast majority should be assessed and deemed unreliable based on routine risk assessment processes and well-established procedures,” he said.

But Eric Schouten, a former intelligence liaison with the Netherlands General Intelligence and Security Agency and CEO of security consultancy Diami, said changing existing procedural regulations would take time and would require balancing the views and responsibilities of countries, airports, security authorities and the European Union, with geopolitics also a factor.

“Many more flights are likely to be canceled or diverted. Railways and highways could be the next targets,” he said.

“But they will understand. This is not the first time airlines have had to deal with hoax calls, because there are always copycats.”

He added: “Whatever measures we take to address this, we won’t share it publicly because we risk alerting bad actors.”

Wilfried Covent said there would be no immediate changes to assessment protocols, but “if this really is going to go on forever, something will have to change or we will have to stop flying altogether.”

“Given what we’ve seen in the past with other types of threats, the types of attacks are likely to change and evolve over time,” he continued, pointing to the recent wave of cyberattacks hitting supermarket refrigerators and blood banks.

“As Europeans, we need to be prepared.”