United Airlines is trying to bring back supersonic travel.
It announced it's buying 15 new jets from a Denver startup.
The jets would carry between 65 to 88 people at a speed of Mach 1.7 and it would cut flight times almost in half.
A flight from New York to London would be 3.5 hours compared to the normal 6.5 hours.
United plans to have passengers on-board by 2029.
