Analysis of the air cargo transport network using a complex network theory perspective

Abstract

In this paper, we present a complex network analysis of the air transport network using the air cargo, instead of the passenger, perspective. To the best of our knowledge, this is the first work where a global cargo network comprising passenger airlines, full-cargo airlines, and integrators' capacity was studied. We used estimated yearly cargo capacity between airport pairs as input to the model. After assessing network characteristics of the sub-networks representing different carrier types, the full network was obtained as a super-imposition of the individual sub-networks. The resulting network has both small-world and scale-free characteristics. Its topological properties resulted in a higher flow imbalance and concentration with respect to its passenger counterpart, with a smaller characteristic path length and diameter. This result is consistent with the larger catchment area of cargo airports, which heavily rely on road feeder services for the ground leg. Finally, we showed how different attack strategies result in hubs of hub-and-spoke systems or airports behaving as bridges between communities being attacked first. We believe this work to be of relevance both for academics and for practitioners in an era where, due to the soaring of e-commerce and next day delivery, new players are entering the air cargo business and competition is constantly increasing.

Impacts of COVID-19 on Global Supply Chains: Facts and Perspectives

“…2) Shutdown of Commercial Aviation: The shutdown of commercial aviation severely limited air cargo capacities making it harder to move vital supplies such as medical equipment to fight the outbreak around the world. It is estimated that more than $6.2 trillion worth of goods are transported by air every year and that air cargo represents more than 35% of the value of the world trade [21], [22]. However, around 50%-60% of all airfreights are transported in the belly of passenger planes.…”

Integrators' global networks: A topology analysis with insights into the effect of the COVID-19 pandemic

“…This behavior is consistent with a network characterized by a single “top-hub”. On the other hand, DHL seems to be a hybrid version of a hub-and-spoke network, as already highlighted in ( Malighetti et al, 2019a ; Bombelli et al, 2020 ), where LEJ, CVG, and to a slightly lesser extent HKG share the control of the network. Both strength and weighted betweenness confirm this hybrid system for the DHL network, where no top airport clearly outperforms the others, resulting in more balanced cargo capacities between geographical regions.…”

“…As such, modeling integrators' networks with undirected edges and, as a consequence, using network indicators that do not consider directionality of connections (as the γ index in the paper) might lead to biased results. This issue was addressed in ( Malighetti et al, 2019a ; Malighetti et al, 2019b ) and ( Bombelli et al, 2020 ), where the analysis of integrators' networks was carried out considering the directionality of connections. In ( Malighetti et al, 2019a ) and ( Malighetti et al, 2019b ) the authors focused, respectively, on the European and Asian network structure of FedEx, UPS, DHL, and TNT (the analysis covers a time-period prior to the FedEx acquisition), which are based on a limited temporal dataset of one week.…”

“…In both works, the different strategies of the main integrators were highlighted, with DHL focusing more on efficiency and exhibiting the highest centralization and the lowest density, and FedEx and UPS showing a higher density and transitivity and a lower centralization. In ( Bombelli et al, 2020 ), the authors relied on a temporally larger dataset and focused on the global networks of FedEx, UPS, and DHL. After some preliminary considerations on the different networks, that confirmed the different characteristics of the networks at the global scale, most of the complex network analysis addressed the global air cargo transport network that also includes passenger airlines.…”

“…While the literature is relatively rich of works addressing the network structure of airlines using a passenger perspective ( Guimera et al, 2005 ; Malighetti et al, 2008 ; Paleari et al, 2010 ; Lordan et al, 2014 ), the cargo counterpart is still a fairly unexplored territory, especially when it comes to integrators. To the best of our knowledge, academic papers only focused on basic properties of integrators' networks ( Bowen, 2012 ; Bombelli et al, 2020 ), or were spatially and temporally limited to subsets of the global networks ( Malighetti et al, 2019a ; Malighetti et al, 2019b ). This factor is consistent with the difficulty to find reliable and complete data on air cargo operations, where confidentiality and competition are crucial factors.…”