Systemic delay propagation in the US airport network

TL;DR

This paper analyzes how delays in the US airport network can propagate systemically, identifying key factors and modeling delay patterns to assess the risk of systemic instability in air transportation.

Contribution

It introduces metrics and a model to quantify and reproduce delay propagation, highlighting the role of connectivity in systemic delay spread.

Findings

Delay propagation can lead to systemic instability even under normal conditions.

Passenger and crew connectivity are key internal factors in delay spreading.

The model accurately reproduces observed delay patterns in US airports.

Abstract

Technologically driven transport systems are characterized by a networked structure connecting operation centers and by a dynamics ruled by pre-established schedules. Schedules impose serious constraints on the timing of the operations, condition the allocation of resources and define a baseline to assess system performance. Here we study the performance of an air transportation system in terms of delays. Technical, operational or meteorological issues affecting some flights give rise to primary delays. When operations continue, such delays can propagate, magnify and eventually involve a significant part of the network. We define metrics able to quantify the level of network congestion and introduce a model that reproduces the delay propagation patterns observed in the U.S. performance data. Our results indicate that there is a non-negligible risk of systemic instability even under normal operating conditions. We also identify passenger and crew connectivity as the most relevant internal factor contributing to delay spreading.