航空公司在航空貨運中心市場規模之研究

Abstract

本研究以解析性的方法將航空公司在航空貨運中心所服務之市場分為 轉運市場與當地市場。其中轉運市場方面，考慮運量、距離與飛機大小等 經濟性而構建成本函數，並比較直接運送與轉運之成本，透過路線選擇而 得到轉運市場。之後，將當地市場納入分析，探討兩市場合併後透過規模 經濟對彼此所造成的影響，加以整合而得到航空公司在航空貨運中心的市 場規模。在完成基本模式的分析後，加入時間限制，考慮當航空公司提供 各種不同時間限制的快遞服務時對市場規模的影響。並以包含亞洲各主要 機場及其他地區門戶機場的航空貨運路網進行範例分析。 由本研究的結果可求得在各種距離、流量下的最適機型；亦可針對各航線 畫出其臨界線做為路線選擇判斷的指標。從敏感度分析中發現當貨物時間 價值越高時，越容易選擇透過空運中心轉運。另外，轉運市場與當地市場 的互動分析結果顯示當地市場的改變對轉運市場的影響不大。若貨物送達 目的地之時間限制越短，各航線亦較適合選擇轉運路線。對於路網中貨物 流量太少的航線，若要提供快遞服務，將大幅提高總運送成本，故考慮排 除此一航線於路網外。 本研究的成果，不但在學術上可作為未來發展貨物轉運或航空貨運相關研 究之參考，所發展的模式亦可作為航空公司規畫其航空網路、航次與飛機 機型選用的考量。此外，由不同航空站市場之比較，亦可評估航空站成為 空運中心的可能性，及作為航空公司選擇其空運中心之依據。 In this study, we will develop an analytical model on estimating the freight market size of an air carrier at a hub. The freight markets at an air hub are divided into transshipment and local O&D(origin and destination) market. The transshipment freight market at an air cargo hub will be obtained by accumulating freight flows, whose total logistic costs are less when shipped through the hub than when shipped directly from their origins to destinations. We will formulate these logistic cost functions with economic characteristics of an air cargo hub such as economies of scale, economies of stage length, economies of plane size and hub operating efficiencies. Then the local market at a hub will be formulated and integrated with the transshipment market to analyze their interactions and to yield the total market. A case study with a freight network covering major airports in Asia and a few gateways in other regions of the world will be provided to illustrate the application of the model. For each link with specific flow and range, the model provides procedures to find the optimal aircraft, which yields the minimum cost. The study also identifies critical route flows which decide the optimal routing for freights shipped between origin and destination airports. The sensitivity analysis of the model shows that the routing via a cargo hub will increases when the time value of an air shipment raises. In addition, the analysis on the interaction between local and transshipment markets show s that changes in local market size do not significantly affect transshipment market. When shipping time is restricted to be shorter, freight on any route is more suitable to be shipped through the hub. Finally, air carriers may consider to exclude the route with little flow from a express-service freight network due to its markedly effects on raising total shipping cost. The results of this study not only can be a building block for future studies on air cargo hub market or location problems, but can shed light on routing, scheduling and fleet planing for air carriers. In addition, the developed model also can be used to evaluate the potential markets of several airports in a region in order to locate an air cargo hub for carriers.