Effect of the boundary layer on the base pressure in a two-dimensional flow with a Mach number $\mathrm{M}=5$

New data on the base pressure in a two-dimensional ow with a Mach number $\mathrm{M}=5$ are obtained for a wide range of variation of the normalized boundary-layer thickness in the flow-separation cross section. The test results are compared with Tanner’s theory, and a conclusion is made that this numerical model has to be corrected.