Engine-out capabilities assessment of heavy lift launch vehicles

A standardized engine-out capability (EOC) has not been studied exhaustively as it pertains to human-rated space launch systems. This work provides an approach to realizing the necessity of EOC for any launch vehicle system design, and also presents a systematic series of measures to assess the value of adding EOC to a specific system. A derived top-level approach to engine-out (EO) philosophy for a heavy lift launch vehicle is given herein, based on an historical assessment of launch vehicle capabilities. The methodology itself is not intended to present a best path forward, but instead provides three parameters for assessment of a particular vehicle. Of the several parameters affected by this EOC, the three parameters of interest are reliability with sub-parameters of Loss of Mission (LOM) and Loss of Crew (LOC), vehicle performance, and cost. The intent of this effort is to provide insight into the impacts of EO capability on these parameters. The effects of EOC on reliability, performance and cost are shared, including how these important launch vehicle metrics can be combined to assess what could be considered overall launch vehicle affordability.