St. Louis Lambert International Airport (STL) sits at the center of this Reddit thread as a case study in what happens when a hub carrier abandons a market. The airport's passenger traffic has fallen roughly 50% from its peak year 2000, when Trans World Airlines (TWA) operated a major connecting hub there. American Airlines acquired TWA in 2001 and, following the 2008 merger fallout and years of gradual hub de-emphasis, effectively downgraded STL to a spoke airport rather than a connecting hub. The physical remnants of that decline are visible to any pilot or passenger walking through the terminal: entire concourses with shuttered gates, empty jet bridges, and an underutilized terminal footprint sized for a traffic volume the airport no longer sees. STL is far from unique—the thread's replies (implied by the framing of the question) likely surface similar stories at airports like Pittsburgh (PIT), Cincinnati (CVG), and Memphis (MEM), all former hub airports that lost their anchor carriers to consolidation and now operate with capacity built for a bygone era.
For working pilots, particularly those flying for regional carriers, business aviation operators, or cargo airlines, these "dead" hub airports carry real operational significance beyond nostalgia. Underutilized major airports often mean shorter taxi times, more available gate space, less congestion in the terminal airspace, and sometimes more favorable slot or parking availability—all of which matter for scheduling reliability and fuel planning. But the flip side is economic: fewer scheduled flights mean fewer diversion options with robust ground support, maintenance capability, and de-icing infrastructure. A Part 135 or Part 91 crew planning an alternate airport needs to know whether a facility that looks robust on the sectional chart still has functioning FBO services, fuel availability, and adequate snow removal equipment on staff around the clock. Airports that have lost their hub status frequently see reduced operating hours for services that used to run 24/7, which is a real planning consideration for late-night or early-morning operations.
The broader trend illustrated by STL's decline traces directly back to post-deregulation consolidation in the U.S. airline industry. The mergers that created today's "big four" (American, Delta, United, Southwest) systematically eliminated redundant hubs, concentrating connecting traffic into fewer, larger fortress hubs like Atlanta, Dallas-Fort Worth, Charlotte, and Denver. Cities that once anchored a major carrier's route network—St. Louis with TWA, Pittsburgh with US Airways, Cincinnati with Delta—were left with oversized infrastructure and a fraction of their former flight volume. This has downstream effects for airport authorities, who must maintain and finance facilities built for peak-era traffic using landing fees and terminal rents generated by a much smaller operation, often leading to higher costs per enplanement that get passed to airlines and, ultimately, to fares.
For business aviation and general aviation pilots, these de-hubbed airports can actually become attractive alternatives to congested primary hubs, offering shorter approach sequencing, less ATC delay, and more available ramp space for transient aircraft. Some former hub airports have successfully pivoted toward cargo operations (leveraging existing infrastructure for integrators like FedEx or UPS) or attracted low-cost carriers looking for underutilized gate space at lower cost. Others simply continue to shrink, becoming case studies in how quickly aviation infrastructure investment can become stranded when network airline strategy shifts. Pilots and operators planning routes through or around these airports should treat published airport diagrams and services with a healthy degree of verification, since facility utilization—and by extension, available support services—can change substantially and quickly following a hub's decline.