TAGUCHI METHOD-BASED MAN-HOUR OPTIMIZATION FOR BOEING 777 A-CHECK INTERVAL

Öz

Aircraft maintenance is critical for safety and operational efficiency. For the Boeing 777, A-checks are conducted every 1000 flight hours (FH), resulting in five checks per aircraft annually, with significant downtime and labor costs. This study proposes a Taguchi method-based man-hour optimization model extending the A-check interval to 1500 FH and reducing the number of annual checks while maintaining safety and regulatory compliance. The analysis carried out in this study revealed significant benefits of this interval extension. Annual downtime for the 12-aircraft fleet decreased from 60 to 40 days, allowing 20 additional operational days and generating $1 million in extra revenue. Labor costs were also reduced, with annual man-hours dropping from 1586 to 1153 per aircraft, saving 5196 hours fleet-wide. This optimization translates to $416.000 in labor cost savings annually, with a total financial benefit of $1416 million. Redistributing tasks between A- and L-checks further enhanced efficiency. Tasks such as lubrication and minor inspections were consolidated, and comprehensive cabin cleaning at 1500 FH was supplemented with intermediate cleaning at 500 FH to maintain passenger experience. These adjustments balanced the workload without affecting turnaround time or safety. This optimization demonstrates the potential for significant cost savings and operational improvements in aviation maintenance. Extending the A-check interval increased fleet availability, reduced labor requirements, and ensured compliance with regulatory standards. The findings highlight the importance of strategic maintenance planning and the potential for similar optimizations across other aircraft types and fleets.

Anahtar Kelimeler

• Optimization
• aviation
• aircraft maintenance
• Taguchi method

BOEING 777 A-BAKIM ARALIĞI İÇİN TAGUCHI METODU TABANLI ADAM-SAAT OPTİMİZASYONU

Öz

Uçak bakımı, emniyet ve operasyonel verimlilik açısından kritik öneme sahiptir. Boeing 777’de A-bakımları her 1000 uçuş saatinde (Flight Hours-FH) bir yapılmakta, bu da uçak başına yılda beş bakım yapılmasına neden olmakta ve önemli arıza süreleri ve işçilik maliyetleri ortaya çıkmaktadır. Bu çalışma, Taguchi yöntemi tabanlı bir adam-saat optimizasyon modeli önererek A-bakım aralığını 1500 FH’ye çıkarmakta ve emniyet ile mevzuata uygunluğu korurken yıllık bakım sayısını azaltmaktadır. Bu çalışmada gerçekleştirilen analiz, bu aralığın uzatılmasının önemli faydalarını ortaya koymuştur. Yıllık arıza süresi 12 uçaklık filo için 60 günden 40 güne düşerek 20 ek operasyonel gün ve 1 milyon dolar ekstra gelir elde edilmesini sağlamaktadır. İşçilik maliyetleri de azalmış, uçak başına yıllık adam-saat 1586’dan 1153’e düşerek filo genelinde 5196 saat tasarruf sağlanmıştır. Bu optimizasyon, yıllık 416.000 dolarlık işgücü maliyeti tasarrufu ve toplamda 1416 milyon dolarlık mali fayda anlamına gelmektedir. Görevlerin A- ve L-bakımları arasında yeniden dağıtılması verimliliği daha da artırmıştır. Yağlama ve küçük denetimler gibi görevler birleştirilmiş ve yolcu deneyimini korumak için 1500 FH’deki kapsamlı kabin temizliği 500 FH’deki ara temizlik ile desteklenmiştir. Bu ayarlamalar, geri dönüş süresini veya güvenliği etkilemeden iş yükünü dengelemiştir. Bu optimizasyon, havacılık bakımında önemli maliyet tasarrufu ve operasyonel iyileştirme potansiyelini ortaya koymaktadır. A-bakım aralığının uzatılması filonun kullanılabilirliğini artırmış, işgücü gereksinimlerini azaltmış ve düzenleyici standartlara uygunluğu sağlamıştır. Bulgular, stratejik bakım planlamasının önemini ve diğer uçak tipleri ve filolarında da benzer optimizasyonların yapılma potansiyelini vurgulamaktadır.

Anahtar Kelimeler

• Optimizasyon
• havacılık
• uçak bakımı
• Taguchi metodu

Kaynakça

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