For years, flying with Spirit Airlines felt like breaking the system. Tickets cheaper than a train ride. Flights across the United States for less than the price of dinner. A business model so aggressive that it reshaped how millions of people thought about travel. And then, almost overnight, it was gone. In May 2026, Spirit Airlines ceased operations entirely, grounding its fleet, shutting down customer service, and leaving thousands of passengers stranded across airports in the United States, the Caribbean, and Latin America. What looked like a sudden collapse was, in reality, a slow, structural failure years in the making. This is not just the story of one airline going bankrupt. This is the story of how the modern low-cost aviation model hit its limits — and what that means for the future of global travel.