The paper presents a study for conditions for hydrogen self-ignition and flame spreading in a supersonic combustion chamber at the Mach number for the inlet flow equal to 4. The experimental model is a rectangular channel with a flame stabilizer performed as a backward-facing step. The fuel was injected before the step at the top and bottom walls through 8 round orifices which were oriented at angles 45° or 90°. Testing was performed for a wide range of flow parameters which were close to the flight conditions. The experiments performed allowed an efficient scheme of fuel injection for the processes of self-ignition and flame stabilization, which permits preventing choking the channel. It was found that the choice of the injection scheme and fuel injection pressure are critical for ignition conditions and allow controlling the combustion process.