Mach number which was also unit-first, and may have influenced the use of the term Mach. In the decade preceding faster-than-sound human flight, aeronautical engineers referred to the speed of sound as "Mach's number", never "Mach 1". Mach number is useful because the fluid behaves in a similar manner at a given Mach number, regardless of other variables. As modeled in the International Standard Atmosphere, dry air at mean sea level, standard temperature of , the speed of sound is . The speed of sound is not a constant; in a gas, it increases as the absolute temperature increases, and since atmospheric
Beaujon Mach .07 6061T6 aluminum tubing and a single open pilot's seat. The powerplant is installed at the front end of the aircraft tailboom tube, above the pilot. Standard fuel capacity is . Beaujon Mach .07 The Beaujon Mach .07 is a single-seat, American high-wing, tractor configuration ultralight aircraft. The aircraft is available as plans from Beaujon Aircraft of Ardmore, Oklahoma. Designed by Herbert Beaujon, the Mach .07 is named for its top speed of . Beaujon Aircraft publishes the plans along with six other designs in book form under the name "How to Build Ultralights". The Mach .07 was specifically designed to