 base pressur superson flow base pressur superson flow problem accur predict pressur wake configur base bodi superson flow extrem inasmuch sizeabl portion total drag bodi attribut low pressur region great deal theoret experiment work field exist satisfactori method accur predict paper repres excel effort experiment confirm analyt deduc concept larg amount experiment data bodi shape wedg cone cone-cylind rang mach number 4 data thoroughli discuss respect analyt deduct basi evid accumul conclud boundari-layer thick small base pressur axisymmetr bodi two-dimension bodi base height-to-chord ratio order review believ report contribut field base pressur wake flow phenomena 