By Allen McGhan
(Note that this is the expanded version of this story. If you would like an abbreviated version, please go here.)
I first attended a FlugTag in Miami in 2004 and knew instantly I wanted to participate. While I have a background in Aerospace Engineering, most of my experience is in Ion thrusters and materials sciences, not exactly the skill-set best suited to building a handmade, human powered glider. Having built plenty of remote controlled (RC) aircraft and designing plenty of aircraft and testing them in simulators, I was confident that I could come up with something that might work. This summer, one of my friends and collegues (Ryan Fisher,) mentioned the Redbull Flutag was coming to Nashville. We submitted our application that same day. Ryan is a licensed Drone pilot and has spent his life around aircraft. We quickly added our Pilot, Craig (Tre) Mann. At just 119 lbs, he was light and fearless. Just a few short weeks later we added three more people to the group. Peter Ferguson, a local musician and friend of Fisher’s didn’t have much aviation experience but can run fast and was willing to put in the time and effort required. Next we added Michael Roland, another great runner and supporter of the project. Finally Michael Rybolt was added when we realized he had almost as much engineering and aircraft knowledge as Ryan and myself gained through years of model aircraft construction.
From the beginning, we set out to achieve a distance record. Thoughts of theme’s, skits, music and decorations came secondary to setting a world record. We built several models before we received our final confirmation that we’d been accepted as an entry, spending hours coming up with different ideas. Within a few days of our confirmation we began construction on the aircraft we entered into the competition. With three very knowledgeable people, there was a lot of debate about which design we should go with. Ultimately we agreed that Ryan’s idea of a canard (horizontal stabilizer in front) would work best for a glider pushed off a deck from the rear. A canard style aircraft has the front stabilizer set three degrees higher than the rear wing so that it will always stall before the rear wing preventing it from tipping over backwards. Also, because both the front and rear wings provide lift, you maximize lift and the center of gravity will not move depending on pilot weight. Finally, canards are unusual and look unique which might add some bonus point if it worked. I was cautious about choosing a canard but I wanted to make sure this was a real team effort. Once we had constructed models that achieved consistent results, I became more optimistic.
As soon as we scaled up, I knew we needed to use aluminum tubing and polyIsocyanurate foam board (the silver coated stuff) as our primary structural materials. I figured using Tyvek house wrap would be the best coating material, but as soon as Mike Rybolt joined the team, he suggested three-mil lamination film. We were sold on this material during the first tests. He challenged the idea of using PIC foam because most people use the Pink or Blue expanded polystyrene (XPS), but as soon as he saw how much stronger the PIC foam was, he was 100% supportive. While the PIC foam is available at Home Depot or Lowes for just $11 per 4×8 sheet, and the Lamination Film is available on Amazon for $45 per 500′, the aluminum was much harder to come by. Most local suppliers wanted $25+ per eight-foot section which was going to blow the cost of this project out of reach. After hours of research, we found Extruded 6061 Aluminum was drastically cheaper than just about anything else. We opted for round tubing at about $9 per 8′ section and ordered what we needed from online-metals.com They quickly shipped everything in awesome round cardboard tubes. From there we debated adhesives and again Mike Rybolt came to the rescue with standard Gorilla glue. We tried Locktite PL adhesive and it didn’t even come close in terms of adhesion and weight for our application.
We were self-funding to this point and we figured we could build the aircraft our of our own pockets, but we were going to have to cut some corners. We fired up a Kickstarter and within 48-hours were fully funded with great companies like Volunteer Welding Supply, Vapor Emypre, Allegiance Teleservices and Keylink IT making large contributions. Then lots of friends and family added in their support. We used my credit card to buy the materials while waiting for Kickstarter to send us our money and in the end, managed to build the entire craft for less than $1,000 out of our own pockets.
The first build day was the messiest we ever had. We used saws and sanding tools to cut and shape all the ribs. Even with masks, we were coughing and rinsing out our eyes. While PIC is easily cut and shaped, it fills the air with dust that my shop air filtration system couldn’t compete with. We later learned that a simple razor blade was all we needed. We cut out all the ribs, added the metal, some reinforcement and within the first week, our craft was already starting to take shape. By the end of three weeks, we had a complete main wing. We tested it by setting both wing tips on benches 20 feet apart and then sitting on the main spar with less than 1/2″ of deflection (bending) which was a huge boost to our confidence. We coated it with lamination film and we were all smiles as the progress continued. We met every Wednesday night and Sunday afternoon for several weeks until we had a working plane. We tested it in front of fans, ran it across the backyard, weighed everything, ate lots of fast foot and pizza, told countless bad jokes and came together as a team and as friends. This was the first project we’d ever worked on together and some of us met for the first time because of this project. But we bonded and had a great time. I still spend countless extra hours each evening in the shop doing all of the one person tasks but it was the team building that really made the project worthwhile.
Almost six weeks before the competition we had completed the build and were ready to test the plane.. Running it across the backyard showed that it was possible for it to fly, but we knew we needed a better test. Living next to a lake and having a friend with a boat, we decided to pull it until it took flight and fly it like a kite. In hindsight, this was a terrible idea. We sprung a leak, didn’t build a strong enough bottom, pulled from the wrong spot, failed to account for surface tension and went too fast. In the end, the aircraft leaped from the water at 24 mph rolled over and crashed into the water. Fortunately, our wing held together with only minor damage to the covering, but the fuselage was destroyed forcing us to redesign it which allowed us to shed about 15 lbs. Within a week we had the new fuselage rebuilt and were ready for the second round of testing. The next time we set the plane on top of a 14′ Jon boat with 2′ tether to all four corners. Then a towline to the boat and a separate tow line to the plane meant that the plane could fly but was at low risk of taking off and tipping over. With that I climbed inside and we embarked on another day of water tests. Inside the plane I could feel it take off at 15 knots and really got a sense of the center of lift. We also learned the plane was heavier that it should have been which left us all a little disheartened. We did some more tuning and finally I came up with the idea to zipline the plane. We build a 275′ zipline in my yard, hooked up the plane and then pulled it over and over again. Finally we put the pilot in and when we had successfully made it across the yard without touching the ground, felt confident we could win. With that, we moved the plane back into the shop and started on the paint with just over a week to go.
Ground Control was not our original name. We submitted ourselves as ASDFG (Always Sailing Directly For Ground), but Red Bull asked us to change it so we submitted Ground Effect, thinking to go with a video game theme and a play on the fact that our aircraft was in fact a Ground Effect Glider. But somehow that was lost in translation. Stuck with Ground Control, we immediately though of David Bowie who had passed just a few months prior. With songs like Space Oddesy and Rocketman, we knew it was something we could work with so we went with it. But the plane ended up looking like a Pod Racer. We added some awesome designs, stickers and props to stay in line with the Bowie and the space theme (a little Star Wars for inspiration). At that point we started working on the running, the cart, and the choreography. However, just a week before flight day, while testing the aircraft, I fell off a ladder and severely banged up my leg and arm. Luckily we had Michael Roland available as an alternate. But then, just three days before fly day, we were struck with another accident. Peter accidentally slipped while cutting out the guitar and cut his leg open, requiring 4 staples. Then Michael Roland couldn’t get off work and we feared that it would be all up to Michael Rybolt and Ryan Fisher to push us to victory. By the time Friday morning rolled around, my leg was feeling betters and Peter was confident that he could participate as long as he didn’t jump into the river.
From the beginning we knew we had to transport the aircraft and since 8′ lengths of aluminum were much cheaper, that’s where we made our joints. We used 1″ tubing with a 3/4″ solid rod as connectors. A single hole and screw on each side held everything together. This made it easy to load up on Thursday night. We covered it in a tarp to ensure it didn’t take flight during the drive and by 6:30am Friday, we were headed to the Flugtag launch site. It took us less than an hour to get everything set up and ready. Then we spent about an hour in the parking lot walking through our routine and working on timing before parting ways.
The next morning, after doing up the pilot’s makeup, we all met and scoped out the competition. It appeared that some teams, like ours, had spent months of work and a lot of money on their aircraft, while others looked like they started a week prior. There were only a handful that really looked like they were going to compete with us, but who knows what anyone thought of our craft. We knew we couldn’t be quite as outrageous as a bunch of grown men acting like babies. We just hoped that our professional looking plane, graphics and awesome props would win us some points. We talked to everyone we could asking questions about other crafts, and making friends. Everyone was great, there was real fellowship and I don’t think I ever felt like it was a competition as much as a giant party. We all shook hands, complemented designs and wished each other good luck.
Rolling to the ramp was probably the most nerve racking part of the event. We built our aircraft on 200mm scooter wheels which we tested to about 30mph on pavement, but crossing grass, dirt, plywood and railroad tracks was certainly not in the original plan. At 21′ 11″ we were one of the larger vehicles, but we still managed to get onto the platform without incident. They blocked our plane in place with a few small rocks while we put on helmets and jackets which was a little scary. No stray gusts of wind blew us off the ramp and not long after we were rolling months of hard work into position ready to take off. It was at that moment I realized we had miscalculated all of our timing. They wanted us to push our plane right to the end thinking that our little wheels wouldn’t support our 120 lb plane and 120 lb pilot for the 70′ run. I begged the official to give us more distance but he insisted. By the time the plane was stopped, we had only 40 feet to run and barely enough room to do our skit. We weren’t able to get into place in time and our song was half over before we were ready. We raced back into place and then started pushing. With all our might we ran right to the end of the ramp and shoved…
Just 2 1/2 seconds later, Craig was sitting on the water giving the all clear. He had sailed 81′ to a picture perfect landing, the plane was still in perfect condition and the crowd went wild. It didn’t matter what happened from that point on, our pilot was safe and we had flown. It might not have been the world record we aspired for, but it was a still a tremendous success. Thank you Red Bull for bringing this event to Nashville. Thank you to our Kickstarter supporters and Belle Cher printing for the awesome shirts and suits. Thank you to our friends and family for everything you did to help make this happen. Thank you to the other contenders for the comradery. And most of all thank you to our team, Ryan Fisher, Craig (Tre) Mann, Michael Rybolt, Peter Ferguson, and Michael Roland, without whom none of this would have been possible. We had a great time, learned a lot and are already talking about how we are going to break that world record at the next Flutag.