>Without altitude and temperature a Mach number is rather useless Actually, no, it's the most important number. See http://womanpilot.com/?p=61 http://womanpi

>Without altitude and temperature a Mach number is rather useless Actually, no, it's the most important number. See http://womanpilot.com/?p=61 http://womanpilot.com/?p=61 (near the end) for why.