A refined calibration technique is presented for five-hole pressure probes operating in the non-nulling mode. The four 3D calibration surface equations required to reduce data obtained from the probe are curve-fit using a 3D curve-fitting program. The relatively simple equations are quick and easy to use for data reduction. The shape of the 3D surfaces are useful in determining if a probe should not be used due to any machining abnormality or damage a probe has sustained. The contours can also be used to determine the range of flow angles a particular probe can measure.
