Tag: Southwest Airlines

Guest Post: Southwest Airlines’ Boarding Overhaul–When Queuing Theory Takes Flight

Providence College Professor Jon Jackson discusses a topic that every flier understands.

For over 50 years, Southwest Airlines has stood out with its open seating policy—passengers lined up, boarded in order, and picked any available seat. That system will soon end. Starting in January, Southwest will introduce assigned seating and its first premium seats, as part of a major redesign of its boarding process. Internally called “Project USA,” this initiative is more than a marketing shift—it’s a deep operational rethink based on one principle: if queuing isn’t good, boarding isn’t good.

Southwest’s new boarding plan is a live experiment in queuing theory and process design, balancing efficiency with customer experience. Boarding is a significant driver of turnaround time—a key metric for airlines. Every minute saved at the gate means higher aircraft utilization, lower fuel costs, and better schedule reliability, writes The Wall Street Journal (Oct 13, 2025).

Astrophysicist Jason Steffen’s boarding process, which boards passengers in a diagonal pattern, minimizes blocking and maximizes parallel activity. Simulations suggest it could reduce boarding times by 30–50%, but it relies on strict compliance and passenger discipline—hard to guarantee in practice.

Southwest’s new system will use a variation of the WILMA method—boarding Window, then Middle, then Aisle seats—to reduce aisle interference and speed up boarding. This approach is validated by queuing research, though the Steffen process is even more efficient in theory.

Boarding an aircraft is fundamentally a queuing problem—a test of bottlenecks, flow efficiency, and human behavior. The new plan introduces nine boarding groups and two parallel lines to create a smoother, more predictable flow.

Classroom Discussion Questions
1. How do the WILMA and Steffen boarding processes differ in terms of efficiency, complexity, and customer experience? Why might Southwest choose a simplified version rather than the most efficient theoretical model?
2. What behavioral factors might reduce the effectiveness of Southwest’s new boarding plan, and how could the airline design around them?

OM in the News: Southwest and Boeing’s Problems Collide

Southwest Airlines is pulling out of some airports and cutting costs as it grapples with delays of new Boeing planes dim its prospects for the year, reports The Wall Street Journal (April 26, 2024). Southwest said it now expects to receive just 20 new Boeing planes this year— well below the 79 total 737 MAX deliveries it had expected.

Southwest, which flies only Boeing planes, is exposed to the manufacturer’s struggles.

The delays will thwart Southwest’s growth ambitions this year, damping revenue and leaving it overstaffed and on the hook for higher costs. The firm had already said it would stop bringing on more pilots and flight attendants as it adjusts to the jet delivery setbacks. Hiring is virtually frozen.

Under pressure to get a handle on quality problems, Boeing is building fewer of its 737 MAX jets—something that has complicated plans for several carriers. The slow down comes as it faces increased scrutiny from the FAA and Justice Department. Boeing shipped just 17 MAX jets in February, eight fewer than in January and half as many as it delivered in November and December.

Southwest, which flies only Boeing planes, is one of the hardest-hit airlines. It is closing its operations at four airports: Cozumel in Mexico; Bellingham in Wash.: Syracuse, N.Y.; and Houston’s Bush.  Southwest rarely exits airports and hasn’t done so since 2019, when it dropped its struggling operation in Newark, N.J., from its route map during a previous grounding of the MAX. It also plans to “significantly restructure” other markets, including slashing flight numbers at Atlanta and Chicago’s O’Hare Airport.

“I won’t downplay the challenges from the Boeing issues—they’re a big deal,” said Southwest’s CEO. “Redoing schedules and staffing forecasts is a costly effort that pulls people away from their work and creates a significant financial drag.”

United Airlines also lost money in the first part of the year because of the grounding of the 737 MAX after the January Alaska door-plug incident.  UAL is pausing pilot hiring for two months and hunting for new planes from Boeing rival Airbus to fill the gap. And Alaska Air said its plans for the year are also in flux as a result of uncertainty on Boeing deliveries.

Classroom discussion questions:

  1. What options do airline operations managers have when delivery of new planes are delayed?
  2. Why doesn’t Southwest spread its supply chain risks by splitting new plane orders? (Refer to Figure 2.8 in your Heizer/Render/Munson text).

OM in the News: The Boarding Logjam

The glacial pace of boarding planes irritates frequent fliers and airline employees, writes The Wall Street Journal (March 3, 2023). Along with other preflight requirements, it also adds costly time on the ground for Southwest and other airlines, which regularly study ways to speed up boarding.

Southwest employees carry mobile devices to speed up processes such as checking bags.

Today, Southwest is on a mission to shave 5 minutes off the time a plane spends at the gate between flights. The average “turn’’ is now 40 minutes for its smaller Boeing 737s and 50 for the larger ones. “If you can collect up enough of these minutes in each turn, then you can start to squeeze out some more flying,’’ says Southwest’s COO.

Research shows boarding bottlenecks are the biggest detriment to turnaround times. Delays in seconds between passengers finding their seats, or sitting in the wrong seat, add up fast. Southwest is testing 11 concepts at four gates at the Atlanta airport. Signs tell passengers they are entering an “innovation zone.’’ The Atlanta project is a big component of Southwest’s 5-minute quest, with goals of saving 2-3 minutes on boarding per flight. Southwest hopes the rest of the time savings can come from efforts including bigger overhead bins, a possible increase in boarding planes from the front and back simultaneously, and paperless takeoff documents.

One of the biggest changes: The stanchions where passengers line up to board have video monitors. They display a boarding countdown, an alert when important announcements are being made and flashing lights when boarding begins. Southwest is also testing a designated preboarding area for passengers in wheelchairs and families boarding together, a staging area it hopes will reduce gate crowding. It went so far as to test different carpet colors for each area—yellow is out because it showed stains.

Southwest brought music to the jet bridge because the team’s research found people move faster to up-tempo music. Preliminary results show the music and prerecorded jet bridge announcements about bin space, seat availability and other information are helping. They answer the questions flight attendants say they hear over and over again during boarding.

Classroom discussion questions:

  1. What other suggestions do you have to speed up the boarding process?
  2.  What tools for process analysis in Chapter 7 of your Heizer/Render/Munson text can be applied in  a case like this?

OM in the News: The Great Southwest Air Christmas Meltdown

On pages 608-9 of your text, the Global Company Profile for Ch. 15 features Alaska Airlines and is titled “Scheduling Flights When Weather is the Enemy.” The case study in the Linear Programming chapter (Module B) discusses how LP software drives staff and plane scheduling in that industry.

Southwest Airlines software is an aging in-house system called SkySolver, which as The Wall Street Journal (Dec 29, 2022) writes: “This Christmas, SkySolver not only didn’t solve much, it also helped create the worst industry meltdown in recent memory.” SkySolver was overwhelmed by the scale of the task of sorting out which pilots and flight attendants could work which flights. Crew schedulers instead had to comb through records by hand.

 Even as SkySolver tried to solve one set of problems, new ones would emerge. Crews and planes were out of place. Phone lines jammed up, and Southwest staffers trying to get assignments couldn’t get through to the scheduling department. The airline was scrambling just to figure out where its crew members were located.

Southwest canceled more than 13,000 flights between Dec. 22 -27, while stranding passengers and bags across the country. This isn’t the first time that a disruption has ballooned at Southwest, and the carrier’s struggle shows how its increasingly complicated network needs a better technology foundation.

Pilots for years complained that SkySolver often spits out fixes that don’t make much sense, sending crews on circuitous journeys around the country as passengers to meet flights, a practice known as “deadheading.”

By Dec. 26, Southwest realized it needed a full reboot. In an effort to get pilots, flight attendants and planes into position, the airline took draconian measures. It canceled two-thirds of its planned flights for multiple days, and locked up seat inventory on its website so customers couldn’t buy tickets for a flight that might ultimately be canceled.

Unlike many rival airlines, Southwest’s planes generally hop from one city to another, rather than orbiting a major hub. That approach lets Southwest maximize use of its planes and crew, but the daisy chain structure also makes its network more delicate—problems in one corner of the country can be difficult to contain.

Classroom discussion questions:

  1. Why did the scheduling software fail?
  2. What options do operations managers have at this point?

Guest Post: Southwest’s Airplane Disruptions

Today’s guest Post comes from Prof. Howard Weiss, who upon returning from Europe, observed an aggregate planning problem.

From October 10 through October 12, 2021 Southwest canceled more than 2400 of its flights due to bad weather and air traffic control problems in Florida, reported The Wall Street Journal (Oct 21, 2021). Your Heizer/Render/Munson Aggregate Planning chapter (Ch. 13) discusses planning for the airline industry and more specifically about airlines that use hubs. But Southwest does not use hubs. Rather it operates a very complex spider web-like point-to-point route network, and thus a flight between two cities in California can be impacted by bad weather in Florida, for example. According to Southwest’s COO, “40% to 50% of the airlines’ planes flow through Florida nearly every day, and many crews change there. So when we have a disruption, a significant disruption, in Florida, it tends to spread to our entire network.” By Friday night, he said, the airline had “well over” 100 planes and crews “that weren’t where they were supposed to be.” 

Your textbook suggests that for successful Aggregate Planning there should be:

  1. Accurate scheduling of labor hours. 
  2. An on-call labor resource
  3. Flexibility of individual worker skills.
  4. Flexibility in output rate

These suggestions are difficult for any airline to follow but even more difficult for Southwest. Of course, the cancellations led to a large increase in the number of customers trying to reach Southwest and because telephone staffing did not increase this led to waits of several hours to reach customer service.

Classroom Discussion Questions

  1. What could Southwest do to appease customers whose flights were cancelled?
  2. How does Southwest’s on-time performance and cancellation rate compare to other airlines’ performance in general? 

 

 

 

OM in the News: Southwest Air’s Operations Problems

Upstart Southwest Air in 1971
Upstart Southwest Air in 1971

At Chicago’s Midway Airport on Jan. 2, Southwest Airlines canceled a third of its flights, lost 7,500 bags and, at one point, had 66 aircraft on the ground—about twice as many as the carrier has gates. Passengers were stuck on the tarmac late into the night.  A severe snowstorm was the main culprit, but Southwest managers also blamed ramp workers, suggesting that 1/3 of them called in sick to protest slow contract talks. The workers say they are chronically understaffed and are being blamed for executives’ mismanagement.

Maybe  Southwest is showing its age–43, writes The Wall Street Journal (April 2, 2014). Once the industry’s brassy upstart, the airline has begun to resemble the rivals it once rebelled against: carriers that were slow-growing, complex and costly to run. As we point out in Figure 2.8 on page 42, to help keep things simple and cost-effective, the airline flies one model of plane— 737—with lean, highly productive employees. Southwest employees do have a more demanding workload compared with others. The airline carries about 3,000 passengers per full-time employee, compared with 1,350 passengers per employee at its bigger rivals. But the average Southwest worker earned nearly $100,000 in 2012– compared with $89,000 at a traditional airlines.

The OM challenges are many.  Southwest is flying fuller planes, connecting more passengers and serving bigger airports that are prone to delays. As a result, some of its operational ratings have plummeted. Last year, it lost more bags per passenger than any other carrier. And after years as one of the most punctual airlines, just 72% of Southwest’s flights were on time in the 4th quarter—dead last in the industry. Further, from 2007 through 2012, Southwest’s cost to fly a seat one mile rose 42%—more than any other major U.S. airline. Southwest also faces costly upgrades to its outdated computer systems—a holdover from its simpler days—to bring them in line with industry standards.  After snowstorms forced airlines to cancel thousands of flights this winter, other carriers’ computers automatically rebooked many customers. But at Southwest, employees had to manually reschedule each disrupted passenger.

Classroom discussion questions:

1. Referring to Figure 2.8, what is Southwest’s OM strategy?

2. What can Southwest do to improve operational efficiency?

OM in the News: Keeping Your Human Resources Happy

southwestIn Chapter 10, “Human Resources, Job Design, and Work Measurement,” we hold out Southwest Airlines as a model of workplace civility. The Wall Street Journal (Aug. 28, 2013), in this article on how hostile work environments cost companies in productivity and creativity, agrees. The Journal writes that the warm-and-fuzzy corporate culture of Southwest includes an entire department devoted to sending employees supportive notes when a family member is ill or congratulations when they have a baby. “We have people here who remember our birthdays when our family members don’t,” says one VP.

But this is rare. Some 96% of workers say they have experienced uncivil behavior and 98% have witnessed it, according to a Georgetown U. study.  A separate recent study showed that 50% of workers felt they were treated rudely at least once a week. Victims of incivility dial back their work effort and are more likely to lash out. Uncivil behavior can “spread like a virus across teams,” adds a professor at Antioch. And the costs can be steep: Cisco Systems estimates the cost of incivility in its organization at $8.3 million annually. That figure takes into account turnover, employees’ weakened commitment to the company and work time that was lost to worrying about future bad behavior.

At the National Security Agency, managers encourage workers to pay someone a compliment or show up early for a meeting. NSA employees who do good deeds are honored as “civility stars,” rewarded with plaques. Even Dish Network, which topped website 24/7 Wall St.’s list of “the worst companies to work for,”  is trying to take a kinder, gentler approach. That has meant summertime concerts and a softened stance toward the company’s attendance policy.  “I wanted it to be a more fun place to work,” says Dish’s CEO. “I think people have a responsibility to treat everybody else the way they want to be treated.”

Some organizations are even setting rules to foster friendliness. At Louisiana’s Ochsner Health System, employees are required to follow the “10/5 rule,” making eye contact with anyone within 10 feet and greeting anyone within 5 feet.

Discussion questions:

1. How can civility be increased in the classroom?

2. Is it the operations manager’s job to keep employees happy?

OM in the News: Comparing Operations Strategies at Delta and Southwest

If there were ever two airlines that had different OM strategies, it would be Southwest and Delta. When you discuss operations strategy (see Southwest’s activity map in Figure 2.8), note that a major part of Southwest’s approach to achieving low-cost competitive advantage is its standardized fleet of Boeing 737’s. This  allows for pilot training on one aircraft, reduced maintenance, constant updating of its fleet (only 11 years old on average), and close relations with Boeing.

The Wall Street Journal (Nov.16, 2012) provides a totally different–and industry unique–approach by Delta.  Delta, the nation’s 2nd biggest carrier, stunned the industry by becoming the first airline to buy an oil refinery, in a bid to trim its highest operating cost, aviation fuel. It runs a huge maintenance subsidiary that tends to its own planes and does third-party work, while other airlines have scaled down or bailed out of that business. But it also  has focused on an asset most airlines avoid: older planes. Today, Delta’s fleet is both old and complex. It has 10 different models among its 725-aircraft, and the fleet’s average age is over 16.6 years. Its 19 DC-9s, which came from the merger with Northwest, clock in at more than 34 years old!

Most of Delta’s rivals already have fewer aircraft types to simplify their fleets because that reduces the cost of training, maintenance and spare parts. They also are chasing every incremental reduction in fuel costs that new aircraft promise to deliver. Delta, by contrast, is picking up the 88 aging Boeing 717s that Southwest is shedding on planes it inherited in its merger last year with AirTran. Southwest was so anxious to maintain its single plane OM strategy that it took a $137 million charge to retrofit them for Delta. Yet even with the planes’ higher fuel and maintenance costs, Delta figures it is saving at least $1 billion on procuring these and other used planes, compared with buying new ones, making them roughly 10% cheaper to operate per seat than new 737s.

Discussion questions:

1. What are the plusses and minuses of Delta’s OM strategy?

2. Why does Delta prefer to purchase, rather than lease, its planes?

OM in the News: How Southwest’s Operations Strategy Gives Low-Cost Competitive Advantage

In an airline industry that is notoriously brutal, writes Slate.com (June 6, 2012), Southwest Airlines just recorded its 39th consecutive year of profitability. How does Southwest do it? It’s all about keeping operations simple. Simpler operations mean fewer things that can go awry and botch up the whole process, as we show in Figure 2.8.

First, while other airline fleets can employ 10 or more types of aircraft, Southwest uses just one, the Boeing 737. The airline’s VP explains: “We only need to train our mechanics on one type of airplane. We only need extra parts inventory for that one type of airplane. If we have to swap a plane out at the last minute for maintenance, the fleet is totally interchangeable.”

Second, Southwest  doesn’t assign seat numbers. Which means that if a plane is swapped out, and a new one’s brought in with a slightly different seat configuration, there’s no need to adjust the entire seating arrangement and issue new boarding passes.

Third, while most other airlines charge to check bags these days, Southwest has resisted the trend. Its “bags fly free” policy  has operations benefits: “When you charge people to check bags they try to carry more on, sometimes more than can fit in the overhead bins,” says the VP. “That results in more bags being checked at the gate, right before departure. And that wastes time.”

Finally, other carriers use a hub-and-spoke system. But hubs  lead to backups as planes queue up awaiting turnaround—cleaning, refueling.  Southwest’s flights are generally point-to-point. The plane lands, goes through turnaround, and often heads right back where it came from. With less interdependence, the network can survive a problem at a single airport. Southwest can turn around planes in about 25 minutes.  A simpler network also means less luggage getting lost in the shuffle.

Discussion questions:

1.Compare Southwest’s operations strategy to that of other airlines.

2. How will adding international flights impact Southwest’s strategy?

Good OM Reading: Great By Choice

How do some companies rise to greatness, especially in a time of upheaval and economic disruption? Jim Collins’ newest book, Great by Choice, studies leadership in turbulent times. If you enjoyed Built to Last (1994) or Good to Great (2001), this is another excellent read. Starting with 20,400 companies, Collins and his coauthor  cut to only seven that they could label with the moniker “10X”.  These 7 were not just successful: they thrived, beating their industry indexes by at least 10 times.

My favorite of the 10Xers is Southwest Airlines, which like other carriers, faced fuel shocks, labor strife, recessions, the 9-11 terrorist attacks, and  more. Generating a profit every year for 30 years while the industry lost billions and furloughed over 100,000 employees, Southwest kept an unwavering commitment to high performance, and it knew to control expansion in good years. When the company started to grow, it didn’t leave Texas for its first 8 years, and by 1996, when more than 100 cities clamored for its service, Southwest opened only 4 new locations.

What did Collins find out about 10Xers, compared to less successful peers? First, they were not more creative or visionary or charismatic or ambitious or lucky or risk-seeking or heroic. But they did have 4 core behaviors: fanatic discipline, empirical creativity, high productivity, and a surprising amount of self-control, as illustrated by Southwest’s expansion approach.

The theme of Great by Choice  is “the 20-mile march”. Imagine making a 3,000 mile walk from San Diego to Maine. On the 1st day you march 20 miles and make it out-of-town. On the 2nd and 3rd days, you march 20 miles. Now  you reach the edge of the desert, with its 100 degree heat and would like to rest in your tent. But you keep the pace–always–regardless of snow, wind, freezing or scalding temperatures, never pushing for a 50 mile day under even the best of conditions. Your competitor starts the same day, but logs 40 miles in his excitement. He slows down on really bad days and may even hunker down in his tent for a week. Who gets to Maine first? It’s these 7 steady trekkers: Amgen, Biomet, Intel, Microsoft, Progressive Insurance, Southwest, and Stryker.

OM in the News: Maintenance at Southwest Airlines

Maintenance may not be the most exciting of all the topics we teach in OM (see Ch.17), but when it’s not done right, it certainly is the most critical. Southwest Airlines found this out–and barely dodged a bullet–when a 5-foot hole ripped through the roof of one of its Boeing 737-300 jets on April 1st. The near tragedy occurred at 35,000 feet during a flight from Phoenix to Sacramento. At least 2 people passed out and a few were injured with the explosive incident, which caused a loss of cabin pressure.

According to the FAA, the airline found and fixed 21 cracks in the fuselage of the same plane 11 months ago during a weeklong inspection. (The 15 year-old plane is part of an old fleet of 288 Boeing 737-300s flying at Southwest–out of 931 worldwide). Today’s New York Times (April 4, 2011) reports that Southwest has cancelled 100’s of flights and found identical cracks in two other 737s.  “It’s amazing it didn’t rip open further”, says a plane maintenance expert.

Southwest has a history of maintenance problems. In 2008, the FAA set a $10.2 million penalty for the airline’s failure to check for fuselage fatigue cracking. In July, 2009, a football-sized hole blew during a flight over West Virginia. Details of the FAA settlement for improved maintenance are considered proprietary. Southwest plans to phase out the older models over the coming years but would be “putting those aircraft that had ‘no findings’ back into immediate service”.

As we wrote in Ch.17, “Maintenance can improve quality, reduce costs, and win orders. It can also be a matter of life and death”.

Discussion questions:

1. What can Southwest, and other airlines, do to prevent such incidents?

2. Why does finding these cracks cost so much and take so long?