Liquid hydrocarbon fuel can also serve as a coolant, absorbing heat from the scramjet body. When the temperature and pressure exceed the critical point, the hydrocarbon fuel enters a supercritical state (Yang in Proc Combust Inst 28:925–942, 2000). The use of supercritical Jet-A fuel can enhance fuel–air mixing and boost overall combustion efficiency (Fan et al in J Propuls Power 22(1):103–110, 2006). The total penetration increases in proportion to the momentum flux ratio and the spacing between the injector holes (Sathiyamoorthy in J Propul Power 36:920–930, 2020). In this study, supercritical Jet-A fuel is injected from two holes arranged in a tandem configuration, into a supersonic crossflow with a Mach number of 1.94. Using the tandem configuration improves the penetration height of the downstream jet, which in turn enhances fuel–air mixing. A comparison is made between the tandem injection of high pressure and temperature kerosene and supercritical kerosene. The same comparison is conducted for side-by-side injection to evaluate the differences in performance. Flow visualization techniques such as Schlieren imaging, Mie scattering, and oil flow visualization are employed to study the behavior of the fuel injection under both configurations. Further tests will be conducted by varying the injection conditions, specifically the pressure and temperature, to better understand their influence on fuel penetration and mixing efficiency.