Task-Specific Airfoil Design for Fixed-Wing UAVs in High-Climb Reconnaissance Missions: A CST and XFOIL-Based Approach

Abstract

This study presents a systematic airfoil optimisation framework for fixed-wing unmanned aerial vehicles (UAVs) operating in high-climb reconnaissance missions. Emphasising the climb phase, critical for early surveillance and mission efficiency, the approach combines Class-Shape Transformation (CST) geometry parameterisation with XFOIL-based aerodynamic simulations. Three baseline airfoils (NLF1015, SG6042, TL54) were modified through CST to produce optimised variants. The climb phase was segmented into four altitude-dependent intervals, each analysed using a weighted angle-of-attack (AoA) strategy to reflect realistic aerodynamic demands across varying atmospheric conditions. Simulation results indicate significant improvements in lift-to-drag ratio, climb rate, and time-to-altitude for the optimised designs. The SG6042-derived variant delivered the most balanced performance, with strong lift and stable aerodynamic efficiency. The TL54-based profile achieved the lowest drag, favourable in energy-constrained scenarios. In contrast, the NLF1015-based variant showed limited improvement due to high drag sensitivity at elevated AoA. This study demonstrates the value of phase-specific aerodynamic optimisation in UAV design and supports the use of CST and XFOIL as efficient tools for early-stage performance refinement. The framework offers a foundation for future work involving higher-fidelity CFD models and multi-objective optimisation methods.

Keywords

• Airfoil Optimisation
• Fixed-Wing UAV
• Climb Performance
• CST Method
• XFOIL Simulation

Yüksek Tırmanışlı Keşif Görevlerine Uygun Sabit Kanatlı İHA’lar İçin Göreve Özel Hava Profili Tasarımı: CST ve XFOIL Tabanlı Bir Yaklaşım

Öz

Bu çalışma, yüksek tırmanışlı keşif görevlerinde görev yapan sabit kanatlı insansız hava araçları (İHA'lar) için sistematik bir kanat profili optimizasyon çerçevesi sunmaktadır. Erken keşif ve görev verimliliği açısından kritik öneme sahip olan tırmanış safhasına odaklanan yaklaşım, Class-Shape Transformation (CST) tabanlı geometrik parametrelendirme ile XFOIL tabanlı aerodinamik simülasyonları birleştirmektedir. Üç referans hücum profili (NLF1015, SG6042, TL54), CST yöntemiyle optimize edilmiş varyantlara dönüştürülmüştür. Tırmanış safhası, irtifaya bağlı olarak dört alt aşamaya ayrılmış ve her biri, farklı atmosfer koşullarında ortaya çıkan gerçekçi aerodinamik talepleri yansıtmak amacıyla ağırlıklı hücum açısı stratejisiyle analiz edilmiştir. Simülasyon sonuçları, optimize edilmiş tasarımlarda kaldırma/sürükleme oranı, tırmanış hızı ve irtifaya ulaşma süresi açısından anlamlı iyileşmeler olduğunu göstermektedir. SG6042 temelli varyant, güçlü kaldırma kabiliyeti ve istikrarlı aerodinamik verimlilik ile en dengeli performansı sergilemiştir. TL54 tabanlı profil, en düşük sürüklemeyi sağlayarak enerji kısıtlı senaryolar için avantaj sunmuştur. Buna karşılık, NLF1015 tabanlı varyant, yüksek hücum açılarında oluşan sürükleme hassasiyeti nedeniyle sınırlı iyileşme göstermiştir. Bu çalışma, İHA tasarımında safhaya özgü aerodinamik optimizasyonun önemini ortaya koymakta ve CST ile XFOIL’in erken tasarım sürecinde etkili araçlar olarak kullanımını desteklemektedir. Sunulan çerçeve, yüksek doğruluklu HAD modelleri ve çok amaçlı optimizasyon yöntemlerini içeren gelecekteki çalışmalar için sağlam bir temel oluşturmaktadır.

Anahtar Kelimeler

• Hava Profili Optimizasyonu
• Sabit Kanatlı İHA
• Tırmanış Performansı
• CST Yöntemi
• XFOIL Simülasyonu

Kaynakça

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