Hazard analysis means “investigating an accident before it occurs.” With the increased interactive, dynamic, decompositional, and nonlinear complexity of systems there is a need to shift the focus from component failure and reliability to system hazard analysis in order to build safer systems. Safe systems can have unreliable components if it is ensured that component failures do not create hazardous system states. STPA (system-theoretic process analysis) is a hazard analysis technique based on STAMP (system-theoretic accident model and processes) accident causation model. STPA is capable of finding software errors, design errors, and also unsafe interactions between different system components. STPA is capable of finding more causes of hazards than other methods such as FTA, FMEA, and ETA. Using STPA, detailed system safety requirements are generated which must be implemented in design in order to prevent unacceptable losses identified during analysis. In this paper, we have carried out hazard analysis using STPA for Crew Module Propulsion System of Gaganyaan Mission. When using the state-of-the-art analyses such as STPA, the challenging tasks for system with ever-increasing complexity is to claim the sufficiency of the safety analysis. To address this issue, this paper also extends the coverage analysis from the software development to safety analysis.