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 Five (rather than having it serve solely as an excuse for Spritle and Chim-Chim to stow away in the vehicle). The Mach Five is later modified with gadgets and becomes Speed's alternate car for off-track races such as the Casa Cristo 5000, as well as everyday driving like a normal car. The Mach Five originally belonged to Speed's older brother Rex, who relinquished ownership of it to Speed before he left the Racer home. Speed's main car for races on the WRL track (Thunderhead, etc.) is the Mach 6. The Mach 6 was destroyed in a fixed race, but was later