The FAA hit pause on most US flights for five hours Friday after new tech overloaded its old air traffic systems: basically, the system just couldn't handle it.
While there weren't any immediate threats, officials warned this could happen again.
More than 1 million travelers disrupted
Even with the chaos, over 3,000 planes managed to land safely.
Still, more than a million travelers faced delays or diversions at big airports like Dulles and LAX.
The FAA hopes things will be back to normal before the Thanksgiving rush, but this is a reminder that aviation tech needs some serious updates.