Critical Mach number and slow down as it travels around the aircraft's structure. When the aircraft's airspeed reaches the critical Mach number, the speed of the airflow in some areas near the airframe reaches the speed of sound, even though the aircraft itself has an airspeed lower than Mach 1.0. This creates a weak shock wave. As the aircraft exceeds the critical Mach number, its drag coefficient increases suddenly, causing dramatically increased drag, and, in an aircraft not designed for transonic or supersonic speeds, changes to the airflow over the flight control surfaces lead to deterioration in control of the aircraft. In aircraft
Mach Song to 100,00 copies, distributed through their vast community networks within and without their areas of physical presence. In the aftermath of Hurricane Katrina (2005), Mach Song monthly printed 50,000 additional copies for six months for distribution to hurricane victims. They similarly increased the circulation of Mach Song monthly after Hurricane Ike (2008). Mach Song Mach Song (, literally "Life Stream") is a national monthly bilingual Vietnamese–English newspaper published in Houston, Texas. The paper has a readership of approximately 75,000 in 15 cities across the United States and is published by "Boat People SOS"—a national Vietnamese American 501(c)(3) nonprofit organization. Working