“World’s Most Extreme”: the Tornado Puncher

This week, a film crew on assignment for London’s Channel 4 stopped by our Springfield, Missouri workshop.  As part of their series “World’s Most Extreme” that focuses on vehicles designed for extreme usage conditions, they wanted to record our Tornado Puncher as it underwent a gauntlet of tests.  As the engineer responsible for assessing the validity and significance of these tests, I was on set with my laptop as we simulated tornado wind loading and debris impacts.  They mic’ed me up to capture my genuine reactions as a monster truck drove over the Puncher and more, interviewing me on camera about the engineering considerations of the vehicle and the test’s implications afterwards.  In as natural and unscripted a way as possible, I’ll take you through the action of the day from my angle.

First, let me introduce the vehicle: a brainchild of my friend Russel Gehrke, the Tornado Puncher is a one-person vehicle designed to drive into the path of a tornado and lower to the ground.  It combines automobile aerodynamics with 5 years of tornado shelter engineering, merging wind resistance with debris impact durability.  The body is 1/4″ steel coated with a polyurethane exterior for impact energy absorption.  The V8 engine and chassis are from a low-mileage 1977 Chevrolet Blazer, the frame shortened by 3 feet and engine moved to fit inside the compact angularity of the body.   I’ve been working with him on this monster of a vehicle on and off since Fall 2016, both as a second set of hands and as a sounding board for design considerations.  Here is a picture of the Puncher as we ran over it with a 5000-lb rock crawler (showing that the Puncher’s chassis could withstand an additional 2000+ pounds of loading, e.g. a tree falling on the vehicle during a storm):

For the most exciting test, we rented a 30-ton load cell to see how much force it would take to push or tip the Puncher from the side.  Because the aerodynamic drag from perpendicular winds is greater than winds from the front or rear, this test was designed to determine the wind loading threshold that the vehicle could withstand in the field.  We hooked the rock crawler to the load cell, which was attached to two tow hooks spanning the aerodynamic centroid on the left side of the Puncher. The rock crawler dug its tires into the dirt and gradually ramped up its thrust in an attempt to tow the Puncher sideways across the field.  The load cell maxed out at 6200 pounds before the rock crawler’s tires lost traction with the ground and started spinning.  Based on the dimensions of the Puncher and the knowledge that windspeed increases with height, 6200 pounds of force represents the load of a sustained wind at 145 mph, corresponding to an EF3 tornado.  The position of the vehicle did not budge, indicating that the threshold for tipping or sliding is actually significantly higher than the recorded 6200 lb.  However, the test gives us confidence that the Puncher can withstand an EF3 tornado when lowered to the ground in ‘deployment mode.’

As a finale, we demonstrated impact resistance by using an air cannon to fire representative debris at the side of the Puncher.  First, dowel rods at 2-foot and 4-foot lengths were shot at around 100 mph.  The wood splintered as it pinged off the side of the vehicle, slightly nicking the polymer coating while leaving the steel intact.  Then, we fired a scattershot of spherical ice cubes, varying in size from about 1-1 1/2 inches to represent hail.  The ice shattered harmlessly into smithereens upon impact, making for a mesmerizing slo-mo shot.  All in all, it was a cool way to spend the past couple of days, at a great location in the Southern Missouri Off-Road Ranch near Seymour.  I’ll keep you posted about the show: if I’m not on TV in a few months, at least I’ll be all over the cutting room floor back in London!

The 23rd Symposium on Boundary Layers and Turbulence

Last week, I attended the American Meteorological Society’s biennial conference featuring the latest research in boundary layers and turbulence as well as air-sea interactions.  For those unfamiliar with these sub-fields within meteorology, the researchers presenting at this conference specialize in the observation and modeling of the lowest 1-2 km of the atmosphere.  This information is vital to the computational models behind weather forecasts and climate research, as the transport of air and water as we recognize it (i.e. our weather patterns) are predominantly driven by differences in the absorption of solar radiation at the Earth’s surface.

I was excited to attend because the majority of big names in boundary layer modeling were in the same building for most of the week, in Oklahoma City no less.  By my informal count, there were attendees representing 23 countries.  And the talks didn’t disappoint: from graduate students talking about microscale fog eddies and sea spray droplet transport to octogenarian professors discussing unified theories of atmospheric profiling, the schedule was an interesting and comprehensive introduction to many active areas of boundary layer research.  Some highlights:

• Opening keynote address by Dr. Peter Sullivan, an engineer-turned-meteorologist who has dabbled in several domains of atmospheric science but now focuses on simulating air-sea interactions.
• A plethora of talks about computer simulations (mainly LES) over varied land surfaces, which were my primary reason for attending.  They made me realize that my simulation approach is lousy, but salvageable.
• Results from recent field observation campaigns, including PECAN (Plains Elevated Convection at Night), LAFE (Land Atmosphere Feedback Experiment), WFIP2 (Wind Forecast Improvement Project), ISOBAR arctic profiling campaign in northern Finland, and the Perdigão wind experiment in the mountains of Portugal.
• A summary of atmospheric profiling using drones, led by a joint effort between rival schools Oklahoma and Oklahoma State.  This is a brand new area of research (FAA just cleared preliminary flights in 2016), and they are excited to obtain profiles leading up to severe weather events in Oklahoma.  Great contacts to have, and great people!
• A series of talks by my new friends at Notre Dame about sea spray transport, i.e. the complicated physics you never knew existed in the lowest meter of air above the ocean surface.
• Dinner on the 50th floor of the tallest building in Oklahoma with Dr. Heather Holbach, who flies into hurricanes with the NOAA P-3 research aircraft.  I challenge you to name a cooler job than that!
• A plenary session in which top professors and government-sponsored researchers discussed priorities for future collaborative research.
• Closing remarks from Prof. Sergej Zilitinkevich, an esteemed founder of the field whose paper from 1975 I have studied extensively.

In summary, this was a fantastic opportunity for networking and learning quickly, basically a week-long crash course in boundary layer theory and thorough review of current research.  And it didn’t cost me anything, since I volunteered as a student assistant.  This entailed helping presenters upload their slideshows and operating the timer system from the podium, giving me front row seats to practically every talk that I wanted to hear.  If you’re interested in a specific scientific field, I highly recommend looking into similar opportunities at a relevant conference.  Even though I had no work of my own to present, I met many people who are willing to give me advice on my endeavors and possibly collaborate in the future.  It was a great week, and I’m very grateful that I could make a trip home for it.

Okie Noodling Tournament

I had some fun yesterday: after going to a bluegrass mandolin clinic, my parents and I went to the 19th Annual Noodling Tournament and Festival in Pauls Valley, Oklahoma.  For you non-Okies, noodling is one of many terms used to describe sport catfishing, specifically wrangling a large catfish with your hands.  The festival itself is one big party as well, so grab a light beer and I’ll tell ya about it!

First and foremost, the noodling championship.  The premise of the competition is that around 100 noodlers, men, women, and children, set out to their respective fishing spots at lakes across the state, reaching into underwater crevices until they successfully pull out a large catfish by the mouth or gills.  Catfish have teeth that feel like sandpaper, so barehanding them is not recommended.  They also flail when you try to grab them, as fish do.  After landing their catch, competitors must bring them back to the stage at the festival, where they are weighed, measured, and examined for fishhook holes, lead shot, and other sneaky indicators of nefarious conduct.  Provided they abide by all the rules, whoever brings the heaviest fish by the 6pm cutoff is crowned the champion.

Not the winner, but a photogenic competitor

Of course, not all participants officially win, but all participants get to hold their fish up victoriously, framed by jets of swirling blue fog and encouraged by a cheering and whistling crowd.  We saw the winner of the women’s division come back with a 56 pounder, which she somehow lofted over her head with ease.  Likewise, the winner of the SCUBA division came back with a 58 pounder, one pound shy of the overall champion.  We saw children as young as 9 proudly display their 20-30 pound catches.  The funniest moment was when a Japanese TV personality returned with his film crew: he had wrangled a comparatively gimpy but still impressive 21 pound catfish for his reality TV show, of course providing the appropriate amount of fanfare as he displayed his catch to the crowd.

Apart from the main event, the festival had a number of other things to do, and we could easily have spent all day there.  They had a noodling instructional tank, where you could pay to stand in shoulder-deep water and learn the best techniques for pulling up a catfish.  They had a day-long cornhole tournament that looked to be the most competitive I have ever seen.  And I have to talk about the pageant, where 5 women representing the entire spectrum from age 18-45 vied for Noodling Queen.  After a fundraising and question-answering challenge, the pageant culminated in the two finalists donning waders and jumping into a tub of deer feed.  Overall, in ways I can’t fully explain, this was a really fun event, and I definitely feel like a better Oklahoman after experiencing it!