is this legit
When Kirito woke from his comatose state, he had used maximum-speed wind-element flight to chase after Emperor Vecta, who had abducted Alice. At the time, Asuna knew nothing about the geography of the Underworld, so it was only afterward that she understood how far he’d flown them. In fact, he’d flown a distance of more than six hundred miles in just five minutes, carrying Asuna in one arm. That would be nearly 7,500 per hour, ten times the speed of sound
SAO Volume 20, Moon's Cradle: Chapter 7.