Here is a helpful prop tip speed calculator. Would you like to know how fast your propeller tips are traveling? Enter some different combinations of prop diameter and RPM setting below to find out. Note: Ambient temperature is needed to determine the speed of sound for a particular day. The speed of sound varies according to air temperature. Try different temperatures then you will see just how much the speed of sound can vary.

This calculator can be very useful when trying to determine the ideal propeller speed reduction ratio. You may want your propeller to reach its redline (.88 to .92 mach) at the same time your engine reaches its maximum rpm limit, its redline. To calculate this ratio, divide the maximum prop rpm, as you have determined by using this prop tip speed calculator, into the maximum engine rpm.

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