We all know that hurricane-force wind is nothing to sneeze at, even if we haven’t been in a hurricane ourselves. Seeing the damage that hurricanes can do, it’s hard to argue that you shouldn’t be outside during one. We all know this in theory, but I didn’t know it in practice until my visit to the Glenn L. Martin Wind Tunnel at the University of Maryland, where I had the privilege (horror?) of experiencing category 3, 111 mph wind.
In the 1940s, Glenn L. Martin (of what is now Lockheed Martin), gifted the University of Maryland the money to build a state of the art wind tunnel facility. The tunnel itself, buried in an unassuming campus building, is a closed-circuit of air powered by a massive, 2,000 horse-power engine that looks like something out of a science fiction movie. To generate the airflow through the circuit, the engine spins seven propeller blades that were once the part of a B-29 bomber aircraft.
Companies all over the world come to the tunnel to test cars, airplanes, and other products in winds up to 230 mph (think EF-4 tornado). I wondered if maybe I was standing in the wind tunnel that Tesla Motors tested their Model S in. “I can’t really talk about that,” says project engineer Hareen Aparakakankanange. Strictly classified. However, I do find out that even companies like Rubbermaid come in to test things like garbage cans. When they say that your can won’t blow away in winds up to 50 mph, you can believe them.
As I step into the tunnel, I realize how massive it is. The platform where the testing is done looks relatively small, but the tunnel that surrounds it is huge. Looking out over the cliff in front of the test area, aerospace students Vandit Shah and Patrick King explain that the tunnel is actually a giant Bernoulli principle experiment. The tunnel changes size to focus the airflow where it’s needed in the test area. The 230 mph wind speeds are achievable, in part, because as the tunnel narrows, the air is squeezed into a smaller space. With no where else to go but forward, the air speeds up.
The air speed in the tunnel is monitored from a command-center outside. Instead of equipping the tunnel with anemometers (which would disrupt the flow of air), the velocity is measured by pressure. Tiny holes all over the tunnel are connected to monitors that record the pressure at these points. As air speed increases, pressure decreases. This is how scientists can monitor the speed of the air.
As our geeky chat comes to an end, I realize it’s my turn to face the hurricane. King grabs a harness from a nearby table and Shah heads to to control booth to make sure the tunnel is ready for company. They’re pretty excited and that helps to decrease my level of anxiety, which I realize has been creeping northward over the past few minutes. “You’ll be fine,” King says. I nod in agreement, though it’s these low-risk, high-impact things that tend to keep me up at night. I ask how fast they allow it to go when there are human test subjects. “As fast as they can stand,” he says. Okay — challenge accepted.
My heart pounds a little as the harness is tightened around my hips. I was told not to wear any loose clothing, and I am relieved to have followed that instruction when they describe an unfortunate experience with a female reporter and a button-up blouse a few months ago. As I step into the tunnel, my harness is connected to the straps mounted to the floor of the test area. The last thing I’m told is that there will be a loud bang, and that I shouldn’t panic when I hear it. Yeah, right.
The wind starts calmly and I am now excited. This has got to be a meteorologist’s dream to experience pure, hurricane-force winds. King stands outside the test area with signs ready to tell me how fast the air is flowing. 30 mph, it reads. I spread my arms out like a bird and I’m feeling good.
We hit 40 mph and I think of how amazing it is to feel sustained winds like this, which is hard to come by in nature. 40 mph is a lot stronger than you think it would be, and I start to realize that this is going to be much more extreme than I anticipated.
60 mph: Wow. I am shocked at the force of air. It’s no wonder that 60 mph straight-line storm winds can topple trees. King laughs outside the window at my amazement.
74 mph: Category 1 winds on the Saffir Simpson Hurricane Scale. I haven’t given The Weather Channel’s Jim Cantore the credit he deserves. He’s out there in every land-falling hurricane with winds like this AND lashing rain. It’s difficult to move your limbs, and you struggle to turn your head. I consider writing Cantore an email suggesting he strap himself down when he’s reporting live from a hurricane.
96 mph: This has become less about fun and more about a mission of survival. It’s me against the wind as I am pushed backwards and my harness straps lock into place. I lean into the category 2 wind. Only a couple of minutes have passed but I feel like I’ve been in this tunnel for eternity.
105 mph: At this speed, whatever amount of moisture was in your eyes has been blown away. You need to keep your mouth closed, too, for similar reasons. I strain against the force to give a thumbs up. I am determined to stay in here until I feel the power of a category 3.
111 mph: Finally, category 3. A major hurricane, and “major” doesn’t even begin to describe it. It takes your breath away. Your skin ripples in waves like water. Your heart pounds, and you wonder how any structure survives wind like this. Shah ramps down the power at the control panel and I am amazed at how much I underestimated what this was going to be like.
As I exit the tunnel, I am asked how it felt. “Really intense,” I say, at a loss for words. Wind resistance, which is a good way to measure how wind “feels,” increases exponentially with speed. So, imagine the strongest winds you’ve ever felt, and then multiply that feeling by 1,000 and you might get the idea.
If I had my way, every forecaster would have the opportunity to safely feel the power of a category 3 hurricane. This experience has changed the way I will talk about the power and danger of hurricane winds.