It was a warm, spring day in Lubbock on May 11, 1970. An idyllic afternoon soon transitioned into a dark and destructive evening when two tornadoes ripped through the city.
For more than 30 minutes, the tornadoes terrorized northeast Lubbock. The first tornado that touched down caused minimal damage. The second one, however, was a different story. The category EF-5 tornado, the highest possible category, left death and ruin in the wake of its 200-plus-mile-per-hour winds.
Once the debris settled, all that was left was for the community to rally and survey the damage. The storm bypassed the majority of the Texas Tech University campus, clipping the outskirts, but damaged part of Jones Stadium.
Thankfully, Texas Tech was affected by the storm in a much more productive way.
Two years prior to the tornado, in 1968, a dust storm swept through Lubbock, damaging the light standards east of the football stadium. Kishor Mehta, a Horn Professor of civil engineering, was intrigued by what he saw.
“I remember walking by the stadium on my way to teach a class, and a dust storm was blowing,” he said. “I had noticed that the light standards were moving quite a bit. One of the things in the course I was teaching was related to deflection, or the degree to which a structural element is displaced under a load.
“I told the class, ‘If you really want to see something that is moving as a deflection, look at the light standards.' And somebody spoke up from the back and said, ‘Dr. Mehta, they've already collapsed.' Thankfully, the collapse didn't hurt anybody. But that's when I really became aware of the impact of high winds.”
That collapse spurred Mehta and another engineering faculty member, James “Jim” McDonald, to delve deeper into just how much wind could damage the integrity of certain structures.
“Jim and I put some instrumentation on the light standards when they were being put back up,” Mehta said. “Then, we took some very crude measurements. We didn't have any equipment. Nobody was funding it. It was just done on our own, more out of curiosity than anything else. But the impact of high winds stayed in my mind after that.”
When the tornado occurred in 1970, Mehta saw an opportunity to document the structural damage caused by the powerful winds.
“I said, ‘Well, it would be good to do damage documentation of all these failed buildings, even though the experiment is not controlled, and we don't have any wind data,'” Mehta said. “But just the idea that how they failed, in what direction they fell and the failure mode would help us with our understanding for different types of building.”
Ernst Kiesling, who had just been named the chairman of the civil engineering department in the summer of 1969, agreed with Mehta.
“We had a young faculty, including Mehta, McDonald, Joe Minor and some other people who were looking for research areas, but we had very little going,” Kiesling said. “I viewed my appointment as chairman of civil engineering more or less as a mandate to develop a research program, because we had a graduate program in place but no research to support it. The tornado provided a laboratory for us because there were lots of damaged buildings. We immediately went to work, and that was the start of the wind engineering program.”
The day after the tornadoes touched down, Tetsuya Theodore “Ted” Fujita, a severe storms researcher and meteorologist from the University of Chicago, came to Lubbock to assess the damage. Fujita mapped out the path the two twisters took with intricate detail. The data he gathered from Lubbock and other locations helped him officially develop the Fujita Scale in 1971.
The Fujita Scale, or F-Scale, ranked the strength and power of tornadic events based on wind speed and the damage caused by wind. Monte Monroe, an archivist at Texas Tech's Southwest Collection/Special Collection Library (SWC/SCL) and the Texas State Historian, noted that history was made with Fujita's visit.
“Most people don't think of wind science as a history, but it is history – especially when you're in a place like Lubbock, where the first documented Category-5 tornado hit,” Monroe said. “I'm sure they've hit all over the place before, but this was the first one that helped Fujita create his theory, which became the Fujita Scale. He also determined that it was a multiple-vortices tornado, and we have his hand-drawn maps here at the SWC/SCL.”
Once the Fujita Scale was accepted in 1971, every tornadic storm thereafter was recorded anywhere from an F-0 to an F-5.
While Fujita's findings were a breakthrough in understanding the devastating wind that comes with these storms, Mehta, McDonald, Minor, Kiesling and others felt like it was a bit off.
“Fujita set up the F-Scale, and the Lubbock tornado was one of the first, if not the first, test case for him,” Mehta said. “We were looking at the damage, and he had F-0 to F-5. He said this was an F-5 because concrete buildings were damaged. There was a concrete bridge on the east side that had collapsed. So, to him, these are concrete structures damage. Some of the houses were wiped off the foundation and so on. Fujita had a wind speed range for an F-5 and that indicated the wind speed could be close to 300 miles per hour.
“We worked on it, particularly myself, for almost a year and a half, on some of the specific structures from which I would be able to determine what wind speed it would take to cause that damage. We came to the conclusion that the maximum wind speed in the tornado was probably 250 miles per hour, rather than 320. So, that was one of the major conclusions from our study. The second item, which Joe Minor actually pursued, concluded that a lot of window glass damage to First National Bank at that time was due to roof gravel debris and not the wind.”
Mehta, Minor and the others also concluded it wasn't possible for wind speeds to be as high as Fujita listed in his F-Scale. Thirty years after the Lubbock tornado, in 2000, they used the data they had collected over that time to create a forum to update the Fujita Scale.
“We had a forum with a number of engineers who had done investigations in tornadoes and a number of meteorologists who were also interested in it,” Mehta said. “Beyond the forum, we formulated a steering committee to move forward. The committee said, ‘OK, we'll go through the elicitation process.'”
The elicitation process is an active effort to extract project-related information from all relevant stakeholders.
“All the data, all the damage photographs we had developed, we gave them to the elicitation committee of six people saying, ‘What do you think the windspeed would be to do this kind of damage?'” Mehta said. “The damaged buildings varied from single-family homes to mobile homes, schools, hospitals, metal buildings and warehouses.
“It took quite a bit of effort to review the data. The elicitation process requires that you recycle it. You give it to six people, let them review it independently and have them specify their values. Then, you take those values and get averages off it. Then, you give it to them again and let them talk among themselves. They'll say, ‘Oh, my number is really way too high. Let me look at it again. Maybe it should be a little lower.' That's how we went through the process and developed the new Enhanced Fujita Scale.”
Four years after the forum and the elicitation process, Mehta and other committee members were ready to present their conclusions and develop the Enhanced Fujita Scale.
“In 2004, we gave our findings to the National Weather Service (NWS) in Silver Spring, Maryland,” Mehta said. “Then, they took it and ran it through several committees to see if it was usable. Finally, in 2006, the NWS said, ‘OK, we will accept the EF-Scale for use, but not before February 2007,' so it's almost a year later.
“I had asked the question, ‘Why are you waiting a year?' They said, ‘We have to educate weather service people in every county, and every weather service station, because they're the ones who make the judgment on EF-Scale.' After a tornado, NWS personnel would take a look at the damage and compare it with photographs of the EF-Scale. They would have to match it as close as possible because actual damage is not exactly the same as photographs, and then try to give an EF-Scale rating. That's why the current EF-Scale rating wasn't implemented until 2007.”
Now, tornadic storms are graded on an EF-Scale with wind speeds in an EF-5 designated as 200 mph or greater.
After the tornado – and a little bit of organization – Mehta, McDonald, Minor, Kiesling and a team of other faculty members created the Institute for Disaster Research (IDR) to house all the research they were collecting.
Realizing the team was focused more on wind storms and less on other disasters like earthquakes and hurricanes, they decided to rename the IDR in 1985.
“We changed the name to something that would reflect the wind, so we called it the Wind Engineering Research Center,” Mehta said. “At that time, people in mechanical engineering and chemical engineering were also part of the IDR. They had some part related to wind. Timothy Maxwell was working on wind-related research with the Ford Motor Company because Ford wanted to know what wind speed and turbulence can be expected at eight feet above ground. Generally, our measurements were 30 feet or higher. Because of this interest, we put the instrumentation at eight feet above ground. So, it made sense to name it the Wind Engineering Research Center to reflect all of engineering.”
The Wind Engineering Research Center name didn't last long. After receiving a grant from the National Science Foundation, the center expanded to include faculty research in economics and atmospheric science. To reflect the incorporation of science, the center was once again renamed to the Wind Science and Engineering Research Center, or WiSE.
The WiSE moniker stuck around for almost 30 years. As the center developed and grew, so did funding and other programs. The university received money to start a wind energy bachelor's degree program. The program was given a name: Wind Institute.
To make things more confusing, another faculty member received funding and developed the Wind Resource Center.
“Internally, we were doing similar, but different, things,” Mehta said. “Externally, somebody would look at it and say, ‘What are you doing with three centers?' That's when John Schroeder, who was the director of WiSE at that time, decided to consolidate everything into the National Wind Institute (NWI).”
WiSE officially became the NWI in 2013.
Much like the Lubbock tornado was the impetus for the creation of what is now the NWI, a tornado in Burnet, Texas, in 1972 was the catalyst for another important Texas Tech-led center.
Kiesling traveled to Burnet with the “3-M Team” (Mehta, MacDonald and Minor) after the tornado to assess the damage. There, he noticed a small pantry still standing even though the house that had surrounded it was obliterated. That room sparked the idea for above-ground storm shelters.
An even more vivid example of a surviving room in the midst of total destruction of surrounding buildings was observed by Mehta in 1974 in Xenia, Ohio. This realization further advanced the notion that protecting people from a tornado in an above-ground room is feasible.
“I kind of jumped on that and built some laboratory models of a small room,” Kiesling said. “We knew about the structural integrity of buildings and could assess the resistance to the extreme winds pretty well, but the wind-borne debris was another problem that we knew nothing about. We had little data in the literature. There were a lot of myths in the literature about tornadoes and wind-borne debris but not much factual, useful information. There were extreme reports of what winds could do. There were reports of wells being sucked dry and chickens being plucked clean, but there was really nothing that would help a designer design a building that could resist severe wind.”
Since relying on literature wasn't an option, Kiesling decided to take matters into his own hands.
“We knew very little about the debris impact resistance of buildings or materials, so we had to do some testing of our own,” he said. “Our first testing was very crude because we had no way to launch the missiles or propel them. We devised some drop tests off the architecture building, which was the tallest building on campus. A graduate student, Ray Thompson, built a beam over the side of the building and put some pulleys out there. It was basic, but it gave us a few answers, at least, as to what might work and what might not.”
Shortly after those drop tests, McDonald and Milton Smith, a professor in the Department of Industrial, Manufacturing & Systems Engineering, devised a debris impact launcher that would launch wooden two-by-four boards. That launcher enabled the team to conduct better tests.
“We could do reasonably good testing in the laboratory,” Kiesling said. “We built some above-ground storm shelter models and tested them for debris-impact resistance. That was then the evolution of the above-ground storm shelter and it went from there.”
From there, the Debris Impact Facility was born. In 2000, Kiesling took his decade-long debris impact research and helped establish the National Storm Shelter Association (NSSA), of which he served as executive director until recently.
“The NSSA was developed to combat the lack of knowledge of the damage debris can cause and develop design and testing standards for buildings,” Kiesling said. “Our approach was to say that if you're a member of the NSSA, you will have your storm shelter designed by a registered professional architect or engineer to ensure its structural integrity and have it tested for debris impact resistance. And then those meeting the criteria will affix an NSSA seal on it. That testifies to the purchaser that this is a quality shelter; it has been designed by a registered professional and has been tested to provide protection. It was aimed at giving assurance to the consumer that this is a quality product, and it has worked very well.”
Texas Tech is now a nationwide leader in wind science. From humble beginnings out of the wreckage from May 11, 1970, to the IDR, WiSE, NWI and the nation's first doctoral program in wind science and engineering, it's proof that Red Raiders and the Lubbock community can turn a nightmare into something beautiful.
“It's been a rewarding experience to be part of a team that has basically developed answers and solutions to mitigating severe winds, particularly in tornadoes,” Kiesling said. “I really appreciate being part of an effort that has protected a lot of people and has gained worldwide recognition and credibility.”