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PR ERO = (6,28 x PR PISA R² x PR Alias V) : PR Vmax

PR Vmax: CW, PS SAX view.
PR PISA R:  CD, PS SAX view.
PR Alias V: CD, PS SAX view.


Example:
PR Vmax = 209 cm/s
PR PISA R = 0,55 cm
PR Alias V = 45 cm/s
PR ERO = (6,28 x 0,55² x 45) : 209 = 0,40 cm²