Mach tuck significant in causing a tendency to dive, delta-winged aircraft with no foreplane or tailplane in the first case and, for example, the Lockheed P-38 in the second case. Alternatively, a particular design may have no significant tendency, for example the Fokker F28 Fellowship. As an aerofoil generating lift moves through the air, the air flowing over the top surface accelerates to a higher local speed than the air flowing over the bottom surface. When the aircraft speed reaches its critical Mach number the accelerated airflow locally reaches the speed of sound and creates a small shock wave, even though the
Mach a Šebestová students and incorrigible urchins Horáček and Pažout, are the main antagonists of the series. Mach a Šebestová Mach a Šebestová (in English: Mach and Šebestová or Max and Sally) is a Czech cartoon series. It was created by writer Miloš Macourek, director Jaroslav Doubrava, and animator Adolf Born. The animated characters were voiced by Petr Nárožný. The story follows the adventures of two third-year pupils and a torn off telephone receiver. The first series of 13 episodes was broadcast on Czechoslovak Television in 1982. Mach a Šebestová is one of the most popular series made for children's television programme Večerníček.