The increasing demand for air-breathing propulsion systems in hypersonic aircraft that can operate over a wide Mach number range has led to development of the turbine based combined cycle (TBCC). The high-performance compressed air intake system is a key component of these systems. This study analyzed the requirements for air intake systems of hypersonic aircraft operating over a wide Mach number range. This paper reviews research on the TBCC intake design, especially the internal rotating TBCC air intake system presented by TriJet. This review then summarizes the main challenges facing the development of the TBCC intake and the unique conical shock wave/boundary layer interactions in this intake to provide references for subsequent research work.