Researchers in Australia have identified the main factors contributing to pandemic vulnerability in cities as growing populations centered around airports and air travel itself, as population growth outpaces the response capabilities of urban infrastructure.

Such were the conclusions reached by a multidisciplinary team led by Australia’s Centre for Complex Systems and the Marie Bashir Institute for Infectious Diseases and Biosecurity. Researchers believe it had exposed vulnerabilities in the nation’s health infrastructure.

“We should be wary of the tendency for local population growth to out-strip the carrying capacity of the urban infrastructure,” Dr. Cameron Zachreson of the Complex Systems Research Group said. “It’s unclear when the next outbreak will be—however our policies should prepare us for crisis situations, such as epidemics, rather than simply keep pace with growth under placid circumstances.”

The research marked the first time scientists in this area turned to anonymous data from the 2006, 2011 and 2016 Australian censuses, using them to forge a simulator to track similarly anonymous households and suburbs. The study of daily interactions granted insight into how diseases spread and how infrastructure can be better prepared against them. Unfortunately, though medical infrastructure has increased over the years, major hospitals are regularly operating at 100 percent capacity, and the effects of influenza — especially Swine flu — have been on the rise since 2009.

“The Australian Census has provided comprehensive data with which to calibrate a nation-level model of pandemic influenza spread and investigate the population’s vulnerability to the contagion over a period of rapid urbanisation,” Mikhail Prokopenko, director of the Complex Systems Research Group, said.

Between 2006 and 2016, Australia’s population increased by 4 million people, especially in urban areas like Sydney and Melbourne. The massive population spike and a near doubling of inbound international flights over the same period has opened the traditionally isolated nation to a greater variety of epidemics.

“We hope that our research can lend strength to the argument that keeping hospital beds at a consistent ratio to the urban population is insufficient and will not account for the relative increases in disease prevalence that our simulation results suggest will occur,” Zachreson said.

Herb Kelleher, the co-founder of Southwest Airlines and pioneer of low-cost aviation, “without whom there would be no Ryanair”, has died aged 87.

Kelleher set up his budget carrier in Texas more than 50 years ago and changed the face of flying, stripping back costs and inflight services, opening up air travel to a wider range of people.

His biggest legacy for Europe may have been as a mentor for Michael O’Leary, the Ryanair chief executive, who flew to Dallas, where Southwest is based, in the 1980s to learn how to run a no-frills airline.

Following news of Kelleher’s death on Friday, O’Leary credited the extraordinary growth of the Dublin-based carrier to the lessons of his mentor.

“Herb was the grand master Yoda of the low-fare airlines. He was the leader, the visionary and the teacher: without Herb, there would be no Ryanair, and no low-fares airlines anywhere,” he said.

“His passing is a sad day for low-fare airlines and sales of Wild Turkey bourbon.”

Kelleher had gained publicity from the beginning by promising the lowest fares to customers, or compensating them with a bottle of whiskey if they believed they had paid more than a rival would have charged.

Southwest became an industry powerhouse, a brand infused with the colourful, unconventional personality of its boss. The airline’s first flight was in June 1971, and it grew to fly more passengers around the US than any other carrier, spawning a host of imitators at home and worldwide.

In a statement announcing his death, Southwest said Kelleher had “revolutionised commercial aviation and democratised the skies”.

The company added: “Herb’s passion, zest for life and insatiable investment in relationships made lasting and immeasurable impressions on all who knew him, and will forever be the bedrock and esprit de corps of Southwest Airlines.”

As well as his business nous, Kelleher was known for his extrovert antics and flair for a memorable marketing ploy. When executives of other airlines dismissed Southwest as cattle class for the cheap traveller, Kelleher responded with a TV advert featuring his head covered by a paper bag that he promised to give to any potential customer too embarrassed to be seen flying on his airline.

On another occasion, when Southwest and a rival company were battling to use the same slogan, Kelleher challenged its chief executive to arm-wrestle for the rights. Kelleher turned up in red shorts, lost, but kept using the slogan, with his rival grateful for the publicity Kelleher hadgenerated for both airlines.

Southwest’s current chief executive, Gary Kelly, described working alongside Kelleher as “one of the greatest joys of my life … He challenged people and he kept us laughing all the way”.

Southwest, like the budget carriers that came to emulate it, focused on short-haul flights from point to point, rather than connecting flights and building hub-and-spoke networks as its rivals did.

It pared back inflight service, in the days when airlines promoted the glamour and luxury of cabin life, and used a single model of aircraft, the Boeing 737, to cut costs. Southwest ripped up the blueprint by getting rid of assigned seats, and flew from smaller, secondary airports to minimise costs and delays.

While rivals derided its model, Southwest was making a profit by 1973 and has stayed in the black ever since, an unparalleled streak in an industry known for losses and bankruptcies.

Kelleher became Southwest’s chairman in 1978 and chief executive in 1982, eventually taking a back seat as emeritus chairman in 2001, two years after being diagnosed with prostate cancer. But he remained on the payroll and went to the office regularly.

A law graduate from New York, Kelleher’s low-cost mantra apparently did not extend to stinting on his employees’ wages. He said his people were crucial to the company’s success, to ensure friendly customer service whether the flight was budget or not.

In a 2011 interview, Kelleher said his proudest achievement was that, in an industry where tens of thousands of jobs were lost after September 11, Southwest never made its workers redundant.

Kelleher’s lessons for low-cost aviation

Fly one type of plane
While manufacturers led by Boeing and Airbus tout models for every range and route, potentially maximising the efficiency per passenger, Kelleher decided it was far simpler and more cost-effective to pick one plane and build a network around it, keeping down engineering, maintenance and pilot training costs. He chose the Boeing 737 – as did Ryanair. EasyJet went for the Airbus A320 family.

Drive down costs every year
A laser-like focus on the bottom line put Southwest in pole position, and Ryanair has continued that obsession – although as both have become more established and dominant in their respective markets, Scrooge-ish excess has been downplayed.

Turn around aircraft as quickly as possible
Sweating the assets is crucial when a new plane costs $50m-$100m. The longer the plane is in the sky, the more it earns. Low-cost carriers will now routinely spend as little as 25 minutes on the tarmac between flights – with easyJet executives sometimes seen carrying a bin bag down the plane aisle before landing to help cut cleaning time.

Concentrate on selling seats first
The science of dynamic pricing has evolved, with fares starting as low as needed to fill the planes. Traditional loyalty schemes or air miles have been jettisoned: instead, once the passengers are booked, airlines can make money on ancillaries, from luggage to allocated seats.

FortuneHerb Kelleher, the larger-than-life Southwest Airlines impresario who taught the world that air travel did not have to be the exclusive plaything of the rich, died yesterday at 87.

“Our basic thinking [was that] Southwest would democratize the skies,” Kelleher told me in 2010. “Which we did. I mean, a couple of years ago 85 percent of [Americans] had flown at least one commercial flight as opposed to 15 percent in 1966.”

Kelleher was not the founder of Southwest, but rather the founding lawyer—which came in handy, since the Texas-based upstarts spent five years in court before getting its first plane off the ground in 1971. Why so much litigation? Because back then, as in pretty much all the world, America’s airline industry was a heavily regulated cartel, with the federal Civil Aeronautics Board effectively letting the country’s four main incumbent airlines veto the routes, prices, and even existence of any would-be competitor. Southwest’s investors blew through their $500,000 seed money in legal fees, so Kelleher legendarily vowed to pay out of his own pocket if they lost their appeal to the Texas Supreme Court. They won, and he became CEO.

“One of the [government’s] fundamental purposes was to throttle competition,” Kelleher told me. “Their thesis was that if a new airline was gonna take one passenger—one, that’s what they said—one passenger away from an existing airline, it can’t be certificated….The fact that the existing airlines had 90 percent of all the revenue passenger miles in 1938, and also had 90 percent of all the revenue passenger miles in 1978, at the time of deregulation, would give you somewhat of a hint.”

In our book The Declaration of Independents, Nick Gillespie and I argue that many of the modern world’s best developments came through the combined efforts of three types of people: the theoreticians, who provided intellectual frameworks and persuasion for allowing a good thing to flourish; the deregulators, politicians who got the government out of the way; and the practitioners, who used this marvelous freedom—oftentimes forcing the deregulators’ hands—to democratize a technology, setting off a chain reaction of productivity, wealth, and happiness. Kelleher was emphatically a member of that latter category. As we wrote:

Southwest Airlines exists because Texas is big. Like the now-forgotten Pacific Southwest Airlines (PSA) in California, Southwest was not subject to all those onerous interstate regulations and could [after finally winning its in-state legal battles] fly multiple routes in a large and populous state. The two airlines served as a field experiment to test—and demolish—the federal government’s half-century-old theory that the airline industry, in the absence of tight regulation, would jack up prices, abandon small-town routes, and hinder the development of the industry itself.

That demonstration project proved critical in the federal deregulation of the airline industry. Once allowed to escape the confines of Texas airspace, Kelleher’s airline became the most profitable on the planet, showing the entire world the joys of being free to move about the country.

Southwest [ushered] five key innovations into a sclerotic air-travel industry that had changed little in a half century: (1) unheard-of speed in turning around airplanes for their next flight, (2) a preference for unloved regional airports, (3) variable pricing between flights on the same route, (4) getting out of the meal-serving business, and (5) a conscious puncturing of jet age cool with corny, down-home friendliness.

That combination—minus #5, depending on the airline—can now be found all over the world, though not nearly often enough in the United States, due to lingering government controls on ownership, airports, air traffic, and more.

Kelleher was an outspoken critic, and frequent legal opponent, of the governnment’s ham-handed interventions into the industry, including being the only major airline CEO to come out against the post–9/11 bailout money. But for all his contributions to the deregulation story, and vast riches in business, he will likely be remembered just as much for being a swashbuckling, chain-smoking, only-in-America kind of entrepreneur who would settle legal claims with armwrestling contests and advertise air travel like this: