Nearly half of all European flights may suffer delays today after a system failure at Eurocontrol, the air traffic coordinating body for the European Union, interfered with the ability to manage air traffic demand and capacity, according to the BBC. The system, known as the Enhanced Tactical Flow Management System, is responsible for managing the flow of European air traffic — as well as flights to North Africa and parts of the Middle East — on a daily basis. Eurocontrol operates out of Brussels, Belgium and is responsible for managing around 30,000 flights per day from 41 member states.

The error has forced Eurocontrol’s contingency plan, which involves reducing network capacity by grounding planes starting with 10 percent. However, as the delays build and more planes are grounded and waiting for takeoff, the number of affected flights is expected to grow rapidly and could affect as many as 50 percent of all daily air traffic.

The actual air traffic systems of individual airports are not in jeopardy, Eurocontrol stressed, meaning air travel remains safe and unaffected. However, airport management is severely restricted in its ability to clear planes for takeoff due the system failure, with the BBC reporting some airports clearing only 10 takeoffs per hour. Eurocontrol also says the system failure resulted in the loss of thousands of flight plans, which airlines now need to resend.

https://www.theverge.com/2018/4/3/17193814/eu-eurocontrol-brussels-system-failure-flight-plans-airlines-delays-grounded