Decision-support for Rocket Propulsion Technology evaluation

Abstract

The evaluation of rocket propulsion technologies involves complex trade-offs among performance, reliability, technological maturity, cost, environmental impact, and mission adaptability. These criteria are frequently hierarchical, interdependent, and characterized by uncertainty or incomplete information, making traditional additive or fully compensatory decision models inadequate. This paper proposes a hierarchical interval outranking model to support preferential classification of rocket propulsion technologies under imperfect knowledge. The proposed framework allows criteria to be decomposed into coherent sub-criteria across multiple levels (e.g., thrust performance, specific impulse, structural complexity, scalability, lifecycle cost, and Technology Readiness Level). Interaction effects such as synergy, redundancy, and antagonism among criteria are explicitly incorporated through interaction weights. Uncertainty in performance data, weights, veto thresholds, and majority thresholds is modeled using interval numbers. The method generates credibility indices for outranking relations at each hierarchical level and supports ordinal classification into preferentially ordered categories. This enables decision-makers to conduct both global and dimension-specific assessments while preserving essential structural properties such as monotonicity and consistency. The applicability of the model is demonstrated through a comparative assessment of selected rocket propulsion technologies. Results illustrate how the proposed approach captures complex performance trade-offs and supports transparent, structured, and robust technology evaluation in aerospace decision-making contexts.