This paper describes a methodology aimed at a rapid assessment of the minimum thrust requirement for a given aircraftconfiguration.Thislatterinvolvesatightcouplingbetween flightmissionanalyses,engineperformance,and optimization techniques. The flight performance analysis is used to assess the relatively significant constraints, thus rapidly identifying the feasible design space to meet specific requirements, considering a tradeoff between operation constraints and objectives often of conflicting nature. With conventional procedures, it is rather difficult to find the optimumdesignpoint(matchpoint),becauseofmanyinvolvedobjectivesandconstraints.However,byadoptingthe actual methodology using a subroutine called KSOPT, which solves constraints optimization problem using Kreisselmeier–Steinhauser envelope function formulation, associated with a deterministic optimization algorithm, either sequential quadratic programming or modified method of feasible direction, the overall procedure becomes simpler, because there is only one objective and a constraint, thus avoiding separate optimizations. This present methodologyisthereforemore effectivefrom thepointof viewofrapidityinsearchingforthe optimum matchpoint, and may provide guidance in identifying a potential propulsion system and the necessary data serving to develop a derivative (growth) engine. Nomenclature CD = drag coefficient CL = lift coefficient D = drag force F = vector of objective functions g = constraints of inequality L = lift force M = Mach number S = lifting surface T = total thrust V = velocity W = weight X = vector of variables Subscripts CA = climb in altitude CR = cruise ICS = initial climb segment LA = landing TO = takeoff KS = envelope function