A Monte Carlo Approach for Evaluating the Impact of RECAT on Runway Capacity

Abstract

The constant increase in global air traffic demand continues to put serious pressure on airport runway capacity, particularly at major hubs, where arrival and departure movements occur in rapid succession. A key factor limiting runway throughput is the minimum separation required for consecutive aircraft due to wake turbulence. These conventional separations, which are static and based on broad aircraft weight categories and have often been shown to be overly conservative and operationally restrictive under many traffic and meteorological conditions. Therefore, the RECAT-EU program, developed by EUROCONTROL, has redefined wake turbulence categories and their associated minima. The aim is to establish more flexible and efficient separation schemes that maintain safety while improving capacity. In this study, a Monte Carlo–based simulation framework was developed to evaluate and compare runway capacities under ICAO and RECAT-EU separation standards. Simulations were performed for three aircraft fleets with different traffic compositions, as well as for single-mode and mixed-mode runway operations. The results show that applying RECAT-EU separation minima results in significant capacity improvements of between 14% and 27%, depending on the traffic mix and operational type. These findings confirm that adopting dynamic, optimized separation standards, such as those set out in RECAT-EU, can lead to more efficient runway utilization while maintaining the required safety margins.

Keywords

• Air Traffic Management
• Monte Carlo Simulation
• Runway Capacity
• Ultimate Capacity
• RECAT

RECAT Uygulanmasının Pist Kapasitesine Etkisinin Monte Carlo Yaklaşımıyla Analizi

Öz

Küresel hava trafiği talebindeki sürekli artış, özellikle yoğun merkez havalimanlarında, iniş ve kalkışların art arda gerçekleştiği durumlarda pist kapasitesi üzerinde ciddi bir baskı oluşturmaktadır. Pist verimliliğini sınırlayan temel etkenlerden biri, uçaklar arasındaki minimum türbülans ayırmalarıdır. Uçak ağırlık kategorilerine dayanan bu geleneksel ayırma standartları sabittir ve birçok trafik ve meteorolojik koşul altında gereğinden fazla temkinli ve operasyonel olarak kısıtlayıcı oldukları gösterilmiştir. Bu nedenle, EUROCONTROL tarafından geliştirilen RECAT-EU programı, türbülans kategorilerini ve bunlara karşılık gelen ayırma minimalarını yeniden tanımlamıştır. Amaç, emniyeti sürdürürken kapasiteyi artırabilecek daha esnek ve verimli ayırma düzenleri oluşturulmasıdır. Bu çalışmada, ICAO ve RECAT-EU ayırma standartları altında pist kapasitesini değerlendirmek ve karşılaştırmak amacıyla Monte Carlo temelli bir simülasyon modeli geliştirilmiştir. Simülasyonlar, farklı trafik karmalarına sahip üç farklı uçak filosu için, yalnızca iniş veya kalkışın yapıldığı tek mod ve her iki operasyonun bir arada yürütüldüğü karma mod pist senaryolarında gerçekleştirilmiştir. Sonuçlar, RECAT-EU ayırma minimumlarının uygulanmasıyla, trafik bileşimi ve operasyon türüne bağlı olarak %14 ila %27 arasında kapasite artışı sağlandığını göstermektedir. Bu bulgular, RECAT-EU kapsamında tanımlanan dinamik ve optimize edilmiş ayırma standartlarının, emniyet gereksinimlerini koruyarak pist kullanım verimliliğini önemli ölçüde artırabileceğini doğrulamaktadır.

Anahtar Kelimeler

• Hava Trafik Yönetimi
• Monte Carlo Simülasyonu
• Pist Kapasitesi
• Maksimum Kapasite
• RECAT

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