Hook
Spirit Airlines just announced it’s cutting 32 routes across the Midwest and Southeast. American Airlines, facing the same fuel market, raised business class fares by an average of 18% and kept flying. Both companies blame jet fuel—it jumped 40% in six weeks. Why does the same shock force one airline to shrink and let the other merely adjust prices?
The answer isn’t about better management or luck. It’s about where vulnerability concentrates in any system built around a single expensive input that nobody can do without.
Teaching 1: The Fuel Equation
Jet fuel typically represents 20 to 30 percent of an airline’s operating costs. Only labor costs more. That percentage is the difference between profit and loss for most carriers.
When you buy a $300 ticket, roughly $60 to $90 went to fuel before the plane even pushed back from the gate. The airline already paid for the aircraft (or leases it), already staffed the flight, already committed to the gate and the route. Fuel is the variable that moves, and it moves fast.
Jet fuel prices don’t track crude oil prices as closely as you’d think. Crude oil gets refined into multiple products: gasoline, diesel, heating oil, and jet fuel. The refining process has limited capacity for each product. You can’t just decide to make more jet fuel and less gasoline when airlines need it—refineries are configured for specific output ratios.
This creates what the industry calls the fuel crack spread: the margin between crude oil prices and refined jet fuel prices. When refining capacity is tight, that spread widens. Right now, it’s wide. Several refineries that process jet fuel went offline for maintenance simultaneously. A labor dispute at a Texas refinery took another chunk of capacity out of the market. Demand for jet fuel is up because passenger traffic recovered to pre-pandemic levels, but refining capacity didn’t grow to match.
So airlines face a double squeeze: crude oil prices are up moderately, but the refining bottleneck pushed jet fuel prices up much more. A 15% rise in crude became a 40% rise in jet fuel. The bottleneck amplified the shock.
Teaching 2: Hedging and Vulnerability
Airlines don’t just buy fuel on the spot market like you fill up your car. They hedge—buying futures contracts that lock in prices months or years ahead.
Southwest Airlines became famous for this in the early 2000s. While other carriers were bleeding money as fuel prices climbed, Southwest had hedged aggressively. They’d locked in low prices when oil was cheap. For several years, they paid $30 per barrel equivalent while competitors paid $70. That hedging strategy saved them billions and kept them profitable when others were filing for bankruptcy.
But hedging is a bet. You’re betting fuel prices will rise, so you pay a premium now to lock in today’s price for future delivery. If prices fall instead, you’re stuck paying above-market rates. And if you guess wrong about how much fuel you’ll need, you either have contracts you can’t use or find yourself buying expensive spot-market fuel anyway.
Right now, the airlines that hedged heavily when prices were low are fine. The ones that didn’t—or that bet prices would fall and hedged less—are absorbing the full spike.
Budget carriers get hit harder for a structural reason: margin thickness. Spirit’s operating margin last year was 4%. American’s was 8%, but its premium cabin revenue added another cushion—business class passengers are less price-sensitive, so American can raise those fares significantly and lose few customers.
Spirit has no business class. Every seat is economy. Every passenger is price-sensitive. When Spirit raises fares to cover fuel costs, people book with someone else or don’t fly. The company can’t pass through the cost increase without losing the customers.
Legacy carriers have another advantage: diversified revenue. They make money from cargo, from credit card partnerships, from selling miles to hotels and rental car companies. Budget carriers make money almost entirely from ticket sales. When fuel eats into that single revenue stream, there’s nowhere else to pull from.
Teaching 3: Cascade Effects
A fuel price spike doesn’t just raise ticket prices. It reorganizes the entire network.
Short-haul routes become unprofitable first. A flight from Chicago to Indianapolis takes about an hour. The plane burns fuel getting to altitude, levels off for maybe 20 minutes, then descends. It uses nearly as much fuel as a two-hour flight but carries fewer passengers and charges lower fares—business travelers won’t pay $400 for a one-hour hop the way they will for a coast-to-coast redeye.
When fuel costs spike, those routes go underwater. The plane burns $8,000 in fuel, the tickets brought in $12,000, and after labor, gate fees, and maintenance, the flight lost money. So airlines cut the route. Indianapolis loses six daily departures to Chicago. Passengers drive or stop traveling for work.
Smaller cities lose service entirely. If you’re a regional airport that only gets two flights a day, both to a hub, and both routes just became unprofitable, the airline pulls out. You now have no commercial air service. That’s not hypothetical—dozens of small airports lost service during past fuel spikes and never got it back.
Aircraft orders shift. Suddenly fuel efficiency matters more than capacity. Airlines start favoring the Airbus A321neo and Boeing 737 MAX because they burn 15% less fuel per seat than older models. Orders for larger, less efficient planes get deferred. Boeing and Airbus adjust production lines. Suppliers to those manufacturers cut shifts.
The concept here is cost pass-through: how much of a cost increase reaches the end customer versus getting absorbed by the company. Airlines can pass through some of the fuel cost by raising fares, but not all of it. Raise fares too much and people stop flying. The portion that can’t be passed through comes out of profit—or turns profit into loss.
Budget carriers can pass through less because their customers are more price-sensitive. Legacy carriers can pass through more, especially in premium cabins and on business-heavy routes. This asymmetry means the same fuel spike hits different carriers with different force.
The result is consolidation. Weaker carriers shrink or fail. Stronger ones expand into the space they left behind. Over time, the industry has fewer, larger players. Competition decreases. The survivors have more pricing power. This pattern repeats across industries whenever a commodity shock hits: the shock doesn’t break everyone equally; it breaks the most vulnerable and concentrates market share among those left standing.
Teaching 4: The Efficiency Trap
The deeper pattern here is about what happens when you optimize a system for efficiency and then hit it with a shock.
Airlines spent decades getting more efficient. They reduced the number of aircraft types to simplify maintenance. They cut the time planes spend on the ground between flights. They reduced fuel inventory—why pay to store fuel when you can buy it just-in-time? They hedged less over time because hedging costs money upfront, and shareholders reward short-term profit.
All of that made the industry more profitable in stable conditions. It also made it more brittle.
When you carry minimal fuel inventory, a sudden refining bottleneck means you pay spot prices with no buffer. When you hedge less, a price spike hits your cost structure immediately. When you optimize route networks for maximum utilization, there’s no slack—every route needs to be profitable, so when fuel costs rise, you can’t absorb the hit on some routes while others carry the load.
The efficiency trap isn’t unique to airlines. Hospitals face it with labor costs—nursing shortages spike wages, and hospitals with thin staffing have no buffer. Manufacturers face it with key components—when semiconductor prices jumped, carmakers with just-in-time inventory had to shut down assembly lines.
The pattern is the same: optimize for efficiency, eliminate buffers, and concentrate vulnerability at the bottleneck. Then when the bottleneck gets hit, the whole system reorganizes suddenly and painfully.
Resilience costs money. Carrying extra fuel inventory costs money. Hedging more aggressively costs money. Maintaining spare capacity costs money. Running a less-than-fully-utilized network costs money. Shareholders punish companies that spend money on resilience because it reduces short-term returns.
So companies don’t pay for resilience until a shock forces them to. By then, the cost is much higher—paid in cancelled routes, lost market share, and sometimes bankruptcy.
The question for any system is: where is the bottleneck, and how much shock can it absorb before it breaks? For airlines, the bottleneck is fuel. For hospitals, it’s specialized labor. For manufacturers, it’s often a single component from a single supplier.
You can’t eliminate bottlenecks. But you can decide how much buffer to maintain and how much efficiency to sacrifice for resilience. Most industries choose efficiency right up until a shock teaches them otherwise.
Close
Your ticket costs more, your regional route disappeared, and six months from now the airline industry will have fewer players and higher fares—because jet fuel hit a bottleneck, and systems break where they’re weakest, revealing who built resilience and who just built efficiency.