Developing a strategic framework for airline destination selection: A multi-criteria decision-making approach applied to Turkish airlines

• Combines Entropy weighting and fuzzy logic for airline destination selection. • San Antonio, Portland, and Nashville emerge as strategic destinations for Turkish Airlines. • Integrates quantitative data and expert insights for balanced decision-making. • Sensitivity analysis confirms stability across varying criteria weights. • Offers a scalable tool for strategic route planning and sustainable growth. The purpose of this study is to develop a comprehensive decision-making framework that airlines can use to strategically select new destinations, demonstrated here with a case application for Turkish Airlines. Addressing the complexities of route expansion, the study integrates the Entropy weighting method with the 2-Tuple Linguistic T-Spherical Fuzzy Decision by Opinion Score Method (2TLTS-FDOSM) to evaluate potential destinations across critical criteria, including market demand, economic impact, and regulatory environment. Data were collected from industry reports, expert evaluations, and publicly available aviation metrics to support a thorough and adaptable analysis. Findings from the Turkish Airlines case reveal San Antonio, TX (SAT), Portland, OR (PDX), and Nashville, TN (BNA) as top-ranked destinations, each offering distinct economic and operational benefits. This study contributes to aviation management literature by presenting a versatile, data-driven framework that can guide route selection for carriers in competitive markets. The framework’s ability to balance quantitative and qualitative insights underscores its potential for broader application in network planning, promoting sustainable growth within the aviation industry.