Thank you, Sir.
The reason why I asked is because I read this yesterday:
"The speed of sound (otherwise known as Mach 1) varies with temperature. At sea level on a “standard day,” the temperature is 59°F, and Mach 1 is approximately 761 mph. As the altitude increases, the temperature and speed of sound both decrease until about 36,000 feet, after which the temperature remains steady until about 60,000 feet. Within that 36,000–60,000 foot range, Mach 1 is about 661 mph. Because of the variation, it is possible for an airplane flying supersonic at high altitude to be slower than a subsonic flight at sea level."
But according to the USAF flight manuals, when a chart says . . .
MACH .2 at 5,000 ft.
and says
MACH 2.0 at 35,000 ft.
. . . what I need do to get the speed in "true airspeed knots" is to . . .
multiply .2 x 661.47 = 132 knots
multiply 2.0 x 661.47 = 1,323 knots
?
I wasn't sure if I should multiply the mach numbers by different numbers because each mach number is for a different altitude.