Spillover delay effects of damaging wildlife strike events at U.S. airports

In this paper, we investigate the spillover departure delay effects of damaging wildlife strike events that occur to commercial passenger airlines on flights scheduled to depart in the 24 h following a damaging wildlife strike event. Employing multiple empirical approaches, and investigating various differential effects, we identify significant excess departure delays in the 24-hour post-strike period. Our results suggest that the spillover delay effects of wildlife strike events are largely contained within the airline to which the strike occurred. The estimated effects are particularly large—5.4 to 8.3 times higher than expectation—for immediate within-airline, same-leg flights. Further, the behavior of the estimated spillover delay effects also depend on whether a strike flight’s destination airport is an airline hub or not. Our estimated average treatment effects indicate that, during the 24-hour post-strike period, the average damaging wildlife strike event generates a minimum of 570 aircraft minutes and roughly 40,000 passenger minutes of within-airline excess departure delay. From this, we estimate that damaging wildlife strike events generate around $25 million (2020 U.S. $) in spillover delay costs each year—an external cost borne by airlines, passengers, and the economy at large.