UK flight plan system outage leads to hundreds of cancellations

Air traffic in the UK is recovering from a technology outage that caused widespread flight disruptions and cancellations overnight.

The outage affected a system used by pilots to file flight plans for air traffic controllers, meaning the plans had to be filed manually. 

The issue first arose on August 28 UK time, when the National Air Traffic Service (NATS) advised it was "experiencing a technical issue and had applied traffic flow restrictions to maintain safety.”

Later, NATS issued a statement to clarify that “traffic flow restrictions” did not represent a complete shutdown: “UK airspace is not closed”.

According to The Guardian, the outage resulted in the cancellation of 500 flights.

The outage coincided with a public holiday, with hundreds of thousands of inbound and outbound passengers stranded.

The outage was fixed shortly after 1500 UTC, when engineers "identified and remedied the technical issue affecting the flight planning system." 

"We are now working closely with airlines and airports to manage the flights affected as efficiently as possible," NATS said.

NATS operations director Juliet Kennedy issued an apology for the disruption.

With aircraft and crew out of position because of the cancellations, it could take days before everything returns to normal.