According to CoinMeta, the aviation system failure in the United States has entered its third day, with over 5,200 flights affected as of Sunday. U.S. Transportation Secretary Anthony Foxx expects that air traffic will return to normal on Monday. Data from the aviation information website FlightAware shows that more than 1,600 flights were canceled and nearly 3,600 flights were delayed across the country on Sunday. Foxx stated that flight operations will return to normal on Sunday, but it may take until Monday to fully restore normality. The issue originated after a router replacement at a facility in Eldorado, Arkansas FAA, which led to problems with a recently replaced router in Amarillo, Texas, causing an overload on routers at other air traffic control centers. On Sunday, FAA announced that the functions related to the problematic router had been disabled, and similar measures were taken for about 60 other routers. Foxx pointed out that the ultimate cause of the failure is still unclear, as the same maintenance procedures have been performed thousands of times before without any issues.