Harvard researcher unearths data airlines don’t want you to notice: Three-hour flight delays are 4x more common now than 30 years ago

Travel & Leisure·Air TravelHarvard reer unearths data airlines don’t want you to notice: Three-hour flight delays are 4x more common now than 30 years agoBy Eva RoytburgBy Eva RoytburgFellow, NewsEva RoytburgFellow, NewsEva is a fellow on Fortune's news desk.SEE FULL BIO Long delays at the airport are becoming more common.Getty Images—Jeffrey Greenberg/Universal Images GroupOn one sweltering summer afternoon in June, thunderstorms rolled over Boston Logan International Airport

It was the kind of brief, predictable summer squall that East Coasters have learned to ignore, but within hours, the airport completely shut down

Every departure was grounded, and flyers waited hours before they could get on their scheduled flights

Among those stranded were Maxwell Tabarrok’s parents, in town to help move him into Harvard School, where he is completing an economics PhD

Tabarrok told Fortune he was fascinated by how an entire airport could grind to a halt, not because of some catastrophic event, but due to a predictable hiccup rippling through an overstretched system

So, he did what any good statistician would: dive into the data

Not only that, but Tabarrok found airlines are trying to hide the delays by “padding” the flight times—adding, on average, 20 extra minutes to schedules so a flight that hasn’t gotten any faster still counts as “on time.” Thus, on paper, the on-time performance metrics have imved since 1987, even as actual travel times have gotten longer. “For 15 years, from 1987 to 2000, the actual and scheduled times stayed very close together,” Tabarrok said. “Then, starting right around 2000, they started diverging—a pretty sign airlines made a decision to start padding their schedules to avoid shorter delays.” The padding carries a hidden economic cost

There are far more users in the National Airspace system today than there were decades ago, industry sources say

Department of Transportation data shows weather is the most common cause of non-airline delays

An shortage of air traffic controllers, combined with recent FAA equipment outages, has also disrupted operations worldwide

A structurally unsound system For Tabarrok, the root of the blem isn’t just bad weather, outdated infrastructure, or even airline strategy: It’s incentives

He argues the FAA has little reason to respond quickly to rising delays because the agency doesn’t bear the cost of stranded passengers, nor are they rewarded when airports run smoothly. “I think the costs of delays can double, triple, quadruple over the next 10 years

But is anyone’s career negatively affected at the FAA? bably not,” Tabarrok said

He pointed to the shortage of air traffic controllers as an example

Hiring and training more staff would ease congestion and reduce cascading delays—a very simple solution that many people have called for

However, doing so requires sustained effort and leadership that is actually willing to push through bureaucratic inertia. “You need somebody at the FAA who really cares imving service

That’s not so easy to do because there’s really no incentive for somebody at the FAA to care a lot this… they don’t get paid more,” Tabarrok said. “They don’t really get rewarded at all.” A FAA spokesperson told Fortune the organization prioritizes safety, which sometimes necessitates delays

They pointed to a chart showing the top five causes of delays—with weather being “by far” the largest cause

They declined to answer questions airlines padding schedules and incentives to imve airport quality

Expanding airport capacity, for Tabarrok, is the most obvious long-term solution to reduce the cascading delays

But the U.S. hasn’t opened a major commercial airport since Denver International in 1995, and runway construction at existing hubs has been minimal, he said

While we have built larger aircrafts to help carriers move more people, that’s also created new bottlenecks, he added

Bigger planes take longer to fly at every turn

They take longer to board, unload, and turn around at the gate, so the disruption continues to ripple into the schedule. “The infrastructure at airports is fixed, especially season to season,” Tabarrok said. “So when you have more demand with fixed infrastructure, there’s going to be more delays.” ‘Pessimistic story’ Further, Tabarrok argued big-ticket fixes building a new airport or runways face environmental reviews and legal challenges that can drag on for a decade

That leaves staffing as the most realistic solution, but even that will require changing how the FAA recruits, licenses, and trains controllers. “It’s kind of a pessimistic story,” Tabarrok said. “We have these two constraints that aren’t that responsive to the market pressures of people’s demand for more reliable travel, and they’ve been around for a long time.” Without those changes, Tabarrok predicts the U.S. will be locked into a cycle where every summer thunderstorm or mechanical hiccup crashes airports and wastes millions of hours of Americans’ s. “If you just do some rough estimation of the value of people’s time, multiplied by how much time they’re spending waiting around in airports or waiting around for delays, you can easily get billions of dollars lost every year.” Tabarrok said. “And that cost will keep growing.”Introducing the 2025 Fortune Global 500, the definitive ranking of the biggest companies in the world

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