Ummm...no, it's all a function of blade diameter and the corresponding
circumference of the prop at the tip. At the same RPM, the shorter blade's
tips are traveling SLOWER (due to the smaller circumference) than a larger
blade.

This is true. However, it is not what is (likely) important.

When you change blade length, you need to change something else to
compensate (for what?). Depending on what you will be holding constant,
you will get different results.

Hold RPM constant and power goes down. Hold power constant, and RPM
must go up. If you want to do the same routine with shorter blades,
you'll need to hold power, not RPM, constant.

Jose
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