As claimed by the aviation industry, sustainable aviation fuels offer significant environmental benefits, yet their impact on travel behavior remains underexplored. The current study investigates potential shifts in travel behavior in response to the introduction of zero-emission flights. A stated choice experiment using a sample from the UK general public evaluates preferences for flights, trains, and cars based on travel time, cost, and carbon emissions. Covariates, such as attitudes towards zero-emission flights, flight-shaming norms, and sociodemographic factors, are incorporated into a latent class choice model. Results reveal heterogeneity in zero-emission flight preferences, with subgroups showing high sensitivity to travel cost and distance. Overall, travel choices remain stable even with longer zero-emission flight durations, highlighting ticket price as a primary concern. A group with less sustainable choices, characterized by unfavorable attitudes and flight shame norms, leans towards cars if zero-emission flights are costly for short-haul journeys. Notably, this subgroup with limited preference for zero-emission flights, predominantly male and high-income, shifts strongly to zero-emission flights for long-haul journeys, displaying the lowest price sensitivity.