Supersonic probes

The wedge probes (Figure 2.25) have the advantage over the cylin­drical ones of having higher critical Mach numbers (depending on the angle of opening) and of being much less sensitive to the position of the holes.

They are also suitable for supersonic flows. The influence of the Mach number on the sensitivity of some cones and a wedge can be seen from Figure 2.26; the sensitivity of a wedge of 8° turns out to be equivalent to that of a cone of 30° in the field 2 < M < 5. In the hypersonic regime,

a conical configuration is almost universally used (with angles from 20° to 90°).