What does it feel like to be a hawk speeding like a rocket feet above the terrain before slipping between the walls of a narrow canyon on an exhilarating flight to the bottom?
Typically sport skydivers open their parachute between 4,000 and 2,500 feet above the ground to get 4 to 6 minutes under the canopy. It takes approximately 500 feet for a regular sport skydiving parachute to open. Base jumpers often open their single, specially designed for rapid opening, parachutes much lower to the ground, often between 800 to 500 feet above the ground to get 20 seconds or more under the canopy. It takes 50 to 100 feet for the parachute to open.
You can experience that sensation through one of the fastest growing and youngest extreme activities in the world — skydiving or base jumping in a wingsuit. Unfortunately, it’s also one of the most deadly, which is why a team of Embry-Riddle students and an Aeronautics faculty member are re-engineering wingsuits to improve aerodynamics, performance and safety with the ultimate goal of competing at the 2017 Wingsuit Performance Flying World Cup.
Squirrel suit, birdman suit, bat suit are all common names for this suit worn to prolong the freeflying experience of skydiving or base jumping. An internet search for “wingsuit jumping” produces an abundance of GoPro videos depicting jumpers leaping off the tallest mountains and cliffs in the world, suited up in what appears to be jumpers with cheap blow-up mattresses attached web-like to their arms and legs with a single parachute on their back. You won’t be able to watch a video without feeling your own pulse increase and your stomach flip — whether it’s from terror or excitement. Scroll to the lower half of the search results and words like “deadly” and “more like suicide than a sport” overwhelm the page.
“Yes, it’s possible to make wingsuits safer — and it’s much needed. Just this last year there have been 25 confirmed deaths from both inexperienced and professional jumpers,” said Tim Sestak, A Prescott Campus faculty, Aviation doctoral candidate and wingsuit flyer. “Very few studies have been done on the aerodynamics of wingsuits and all but one of those were done by people who are not aviators. We are using the same engineering process used when building an aircraft. When we are done, our suit will be based on valid science and proven engineering processes.”
This multi-dimensional research project is well suited for the state-of-the art laboratories and resources focused on aerospace at Embry-Riddle. Complementing Sestak’s knowledge as an Aeronautical Science faculty, Aerospace Engineer and Naval aviator are students studying to be engineers or pilots, as well as safety science students who share a passion for flight.
Embry-Riddle Blue Eagles Skydiving Team skydives several times a semester. Students can participate in an Accelerated Freefall Training program leading to solo skydiving at a significantly discounted rate through a partnership with a professional skydiving company in Maricopa, AZ. “Skydive Phoenix” Facebook link: https://www.facebook.com/blueeaglesskydiving?notif_t=page_name_change
“Several of us skydive, and that experience really helps to understand the impact on a body from free-flight,” said Glenn Borland, junior in Aeronautics minoring in Safety, Meteorology and Unmanned Aircraft. “I’ve had my private pilot license since 2009 but my first skydive was November 1, 2014 with Embry-Riddle’s Blue Eagles Skydiving Team. It was awesome! This is a great opportunity to learn and make wingsuits better. As Professor Sestak says, ‘Why fly an airplane when you can be one!’”
There are four main objectives of the team’s research:
- Use a scientific method to design a next-generation wingsuit
- Gather data on the aerodynamic effects of materials currently used on lift and drag
- Study the effects of Leading Edge Deformation
- Incorporate knowledge gained into next-generation wingsuit
Aerodynamics is the starting point for improvement. Glide ratio is a key factor for wingsuits. According to the team’s research, the average wingsuit’s steady state glide is 3 feet forward to 1 foot down. The current record, set at the first Wingsuit World Cup competition is 4.51 feet forward to every 1 foot downward. The team is going for a 6-foot to 1-foot ratio. It is a combination of lift and speed that allows a wingsuit to maintain forward flight and thus increase its steady state glide ratio.
Lift and speed are affected by wingsuit materials and design as well as environmental factors and the pilot’s decisions. Wind tunnel tests revealed that the choice of material can affect lift by 50% positively or negatively. Current wingsuit materials reduce lift by up to 50%. Wingsuit flying also puts a severe strain on the body. Sestak described it as doing a spread eagle push-up for 3 minutes while dropping 13,500 feet out of an aircraft to the Earth.
“Much of the danger in wingsuit BASE jumping is lack of experience. Inexperienced jumpers will jump with poor technique and the suit will fly them into the cliff. Even the super experienced elite wingsuit pilots have died after jumping the same route 50 times,” said Sestak. “When a person flies a wingsuit, they become an airplane. In our wind tunnel tests, we observed conditions at which an increase in airspeed actually reduces available lift. This can be caused by the material of which the suit is made or changes in the leading edge of the wing caused by the air pressure. These conditions can unpredictably result in uncontrolled flight. If you are only 10 or 20 feet off the ground, you won’t recover.”
The team’s current stage of research requires development of 3-D models of the full wingsuit for computer simulation scenarios to further test wing designs. They are also looking at various methods of stabilizing the leading edge of the wings.
CFD explained: Computational fluid dynamics (CFD) uses high powered computers and specially designed software to do numerical analysis that can solve and analyze problems in aerodynamics and other fluid flow problems. This type of computer analysis can not only solve problems to show the speed and pressure of air around a flying body, but is frequently used to produce pictures and other graphic output that allows a person to visualize the airflow around an object. It is very useful in making initial design decisions for aircraft that can be later tested in wind tunnels or in scale or full sized models.
“Computational Fluid Dynamics (CFD) allows you to test digital design concepts in computer model simulations to find optimal design — best lift and glide ratio,” explained Brian Cowley, junior in Aerospace Engineering, who has been developing the CFD models. “At this point we are using as many test validation methods as possible. CFD gives you a great 80% solution so the next step is to 3-D print a scale model of the design and physically test it to validate your findings.”
Sestak and team will use Embry-Riddle’s wind and water tunnels for that validation. The water tunnel is used because when dye is injected in the water, flow visualization and interference can easily be identified revealing nuances in aerodynamics that go beyond the wind tunnel. Once the design validation tests are complete, the team plans to commission a wingsuit manufacturing company for a full-scale prototype and begin the final phase of research and testing.
“I am really passionate about research. This project is great because I’m doing work like CFD that other schools would never let undergraduates do. It’s a great opportunity to be a part of cutting-edge research that will be substantial for society to save lives,” said Cowley. “Every day is a chance to learn.”
The results of their research have been presented at the national aviation conference AirCon 2015, at Embry-Riddle Research Symposiums and are scheduled for AirCon 2016. The team’s research has thus far been funded by an Embry-Riddle Ignite Grant; TonySuits; SBG Systems; AiXiz Service and International, LLC; and LoadStar Sensors.
“Our work will change the way wingsuits are flown. We will open the dialogue about how aerodynamics affects wingsuits, ultimately leading to a safer sport and a suit with superior performance capabilities,” said Sestak. “And, of course, we’d be thrilled to bring home the Wingsuit Performance Flying World Cup!”
To inquire about the Prescott Campus, call us at 928-777-6600 or 800-888-3728, or email Prescott@erau.edu.