This calculator allows you to convert from Yard/hour to Mach (20°C, 1 atm) and in a reverse direction. To convert from Yard/hour to Mach (20°C, 1 atm), enter the amount of Yard/hour into the first input and to convert from Mach (20°C, 1 atm) to Yard/hour, enter the amount of Mach (20°C, 1 atm) into the second input.