21. For low Mach number \ scriptstyle Ma, the drag coefficient is independent of Mach number. 22. Also, compression of the fluid is not applicable, so the Mach number can be disregarded. 23. Conversely, the Mach number of a supersonic flow will decrease until the flow is choked. 24. The Me 262 appeared to have a higher critical Mach number than any American fighter. 25. As a rough guide, compressible effects can be ignored at Mach numbers below approximately 0.3. 26. These problematic phenomena appearing at or above the critical Mach number became known as compressibility. 27. A swept wing delays the onset of this problem by increasing the critical Mach number . 28. The Mach number range can also be extended beyond M 1cr by carefully designing blade shapes. 29. This is also a function of Mach number : 30. Interestingly, the intersection points occur at the given initial Mach number and its post-normal shock value.
