These bypass tubes can be seen behind the final turbine stage (where all of the tubing stops) running along the engine into the after-burner section. Behind the engine sits the convergent/divergent ejectors as part of the airframe. It was a conventional afterburning turbojet for take-off and acceleration to Mach 2 and then it used permanent compressor bleed to the afterburner above Mach 2 where it operated like a ramjet.