An air travel chaos that hit Britain last week was caused by an issue with a flight plan processing system, the National Air Traffic Services (NATS) has reported.
Thousands of passengers were stranded on Aug. 28, as their flights to and from the UK were cancelled owing to the “network-wide failure.”
The issue was identified and fixed on the same day, but has ultimately disrupted travel for the next days.
This caused the entire air traffic system to enter a fail-safe mode.
“The system could not reject the flight plan without a clear understanding of what possible impact it may have had. Nor could it be allowed through and risk presenting air traffic controllers with incorrect safety critical information,” NATS said in a statement on Wednesday.
According to the air traffic services, a failure of this kind has never happened before to the system that previously processed 15 million flight plans in its five years of operation.
The preliminary report (pdf) by NATS was submitted to the UK Civil Aviation Authority (CAA) and shared with the transport secretary Mark Harper and the aviation minister Charlotte Vere.
The report has estimated that more than 1,500 flights were cancelled and around 575 were delayed on Monday due to the incident.
NATS chief executive Martin Rolfe has issued an apology to affected passengers, airlines and airport customers.
“Incidents like this are extremely rare and we have put measures in place to ensure it does not happen again,” Mr. Rolfe said.
If the review find that NATS has breached its statutory and licensing obligations, the CAA will then “consider whether any further action is necessary.”
He suggested that while the airlines will bear the brunt of costs for the air traffic system failure, “it will cost NATS nothing.”
Mr. Walsh called on policymakers to take note and improve the passenger rights system.