Giant Circle Plane

This is a giant RC plane, and these are giant circular wings I've spent the last month building to answer one question. Can circular wings work better than straight wings? I've always been intrigued by the idea of circular wings ever since learning how to make this circular paper plane design as a kid. It could fly further than standard planes with normal wings, even though it looked like it wouldn't fly at all. So this inspired me to start this project where I'd begin by building a small size test plane before constructing a giant scale circle wing aeroplane made from balsa wood to find out just how well a circle plane flies. So how does a circular wing create lift? Well, it's quite simple really. A circular wing works because the top and bottom surfaces work just like a normal aerofoil. As the wing moves through the air at an angle of attack, the top and bottom surfaces create a pressure differential, and this makes the wing go upwards. So this is how a simple circular wing works, but how well would it work on an aeroplane? To start this project, I thought it would be a good idea to build a very simple prototype. For this, I decided to use some extremely lightweight balsa wood and a motor mount and propeller from our new Project Air kits. This was so I could make a very simple rubber band powered plane, removing the need for heavy electronics and things like that. Now the tricky bit, making a circular wing. I drew a wing design on some paper, cut it out with some scissors, and then taped it down to a cutting mat. Next, I could cut strips of balsa wood to make up the wing parts and slowly glue them together one at a time. After removing the wing structure from the board, I could stick tissue paper to one side and then bend the wing into a circle. Adding two of these wings to the fuselage, I'd made my first powered circle wing plane, and now it was time for some test flying. That's incredible! That went for miles! So I'd got the prototype circle plane flying, but I wanted to know if changing the wing sizes and shapes would have any effect on the flight performance. I built a few different wings, but in the end found the design that worked best was to have one large wing as the main lifting surface near the front of the plane, with a smaller stabilizing wing at the rear of the plane. Okay, now I'd found the perfect design for a circle wing aircraft, but how well would it compare to a normal plane? Right, now we're going to do an experiment to see what the difference is between the circle wing plane and a plane with the equivalent wing area just unwrapped. So what we're going to do is a competition between these two airplanes and see which one flies the furthest. We'll also be able to see which one flies better in the wind because it is slightly breezy, which isn't great for these extremely lightweight airplanes. Each one of these weighs about 12 grams. So let's wind them up and, yeah, get going. I thought this competition would be pretty straightforward, but as it turned out, things would go wrong almost immediately. Right, first off, the conventional wing airplane. 150 winds. Three, two, one. Oh no, please don't go on the roof. Oh no, please don't. Oh no, oh, is it going to go round? Please have gone round. Oh no. The straight wing plane had landed all the way up on the workshop roof after being carried away on a gust of wind. Maybe the circle plane would fare a little better. Three, two, one. Oh, look at that. Well, that's not gone the right way either. Oh dear. Well, this clearly hadn't been a very good start to the test. I had an idea to try blowing the 12 gram airplane from the roof with my drone's propellers. And after about 15 minutes, it fell off the roof. Unfortunately, at that point, I also crashed the drone. With the plane retrieved, it was time to repeat the test in the middle of the field. All right, 150 winds in the open field. Three, two, one. OK, that's better. Yes, that's really getting influenced by the wind a lot. And it only flew for a few seconds. The conventional plane managed a flight of just seven seconds in the windy conditions. That one got there. Let's compare it to the circle plane. See how far this one goes. Oh, wow. That is so smooth. That is so smooth. Look at that go. That was so much better. That's crazy. The conventional wing plane was going all over the place. But the circle wing plane, that was that was amazing. Immediately, the circle plane looked so much more stable than the conventional plane and flew for a longer time at just over 10 seconds. I'm going to do it once more just to see if that was a fluke. Right, 150 winds again. Three, two, one. Wow, that's amazing. Look at that go. That was perfect. The stability of this thing is insane. Just every time it gets blown slightly off balance, it will correct itself. So, yeah, even in this wind, it's just remaining really, really stable. So the circle plane had flown for longer and gone further than the conventional wing aeroplane. So that's really interesting. And I'm very intrigued to see if these positive characteristics will scale up more towards the size of a real aeroplane. So what we're going to do now is scale up the circle plane and build a giant RC version to see how well that one flies. And that is certainly going to be very interesting to compare to all of the other types of RC conventional aeroplanes that I've flown. Let's get building. I designed our giant aeroplane in CAD to have a really strong balsa wood structure with all of the parts designed to be laser cut one by one to then go together like a big construction kit. It would be strong in flight, but hopefully it would also be strong enough to survive any heavy landings. Now to get building this thing for real. We needed loads of balsa wood sheets for this project, but thankfully we had a lot lying around from manufacturing the new kits that we've started selling on the Project Air website. And after about a day of cutting, we had loads of ribs, leading edges and trailing edges all ready to be assembled together like a big model kit. To speed things up, I drafted in Emma to help build the second wing. After a lot of super glue, everything was starting to come together. The tricky bit was adding the ribs, but we soon found a good technique and the wing started to look like the CAD model. The main wing was especially tricky as the spar wanted to flop around all over the place, but as soon as the ribs were in, we could switch attention to gluing the leading and trailing edges on. Finally, both beautiful structures were pretty much finished and we could see how much they weighed. It's massive, look at that. Altogether, the wing frames weighed in at just 2.13 kilograms, which is very light for two wings of this size. While Emma sanded the wings nice and smooth, I could turn attention to building the fuselage. I designed this to be a long box shape with strong bulkheads designed to go under the wings to make sure that they had strong mounting points. I made a nice curved nose to help with the aerodynamics and then sanded everything smooth outside. With some mounting plates glued to the bottom of the wing structures, it was time for my absolute favourite part of any build where we could mock everything up together and see what it looked like for the first time. That is so cool seeing it all together. You look tiny. Yeah. This was definitely one of the strangest looking planes I'd ever built, and it really looked more like an art piece than an aircraft at this point. I just hoped that all of this hard work wouldn't get smashed to pieces on the first test flight. What have we done? Now, if you're interested in building things like me, you might be interested to hear about Anydesk, who are sponsoring this video as they're helping to turn cool science project ideas into YouTube videos seen by millions online. So what this means is that Anydesk are basically doing Red Bull in science by giving you the chance to turn your ideas into videos made by creators like myself. All you have to do is head to their website and fill out a form with a YouTuber you'd like your idea to be built by and a description of what your video idea involves. And if your idea ends up being in a video, then Anydesk will send you some swag and you could even get a part of the project or a prop that was involved in the making of the video. If you want to know what Anydesk actually does, then it's a remote desktop software that lets you access and control a computer from somewhere else. And it works over basically everything from phones to Mac to PC to even Raspberry Pi. And yeah, this is free for personal use, but also they have commercial custom tailored plans available for your business use. So go to anydesk.com slash EU slash science. Submit your most crazy project or experiment idea, and you might see it on YouTube. Thank you very much to Anydesk for making this video possible. After spending a few days finishing the airframe off by covering everything with heat shrinkable covering film, the plane was finally ready for its first test flight to see if it would work. The plane hadn't got any motors on it, so this would be simply a free flight glide test just to see if the fragile wings could actually create any lift. Would they survive landing, though? Oh, yes, that wasn't too bad. So the wings clearly were making lift, which was a good sign. I just needed to add a bit of extra mass to the front of the aircraft to stop the plane from pitching back too much. Right. Very scientific way of doing this. This is how NASA works. I've been reliably informed. Nose weight installed. Let's go again. Javelin time. Oh, oh, oh, that was a bit heavier on impact. On that flight, I'd thrown the plane a bit harder and it had gone higher before stalling and hitting the ground with more force. It seemed like the wings had more flex than I'd expected, though, as they had looked like they were about to break. After adding even more nose weight, the plane was gliding pretty well, although I found it did need quite a high angle of attack to get the lift from those symmetrical airfoils. Yeah. Yeah, that's it. The plane had completed its first mission and shown where the balance should be. So now it's time to take it back into the workshop and fit some electronics. But how would it fly as a powered aircraft? I found some brushless motors and propellers that would create enough thrust to power the airplane. But to attach the motors onto the wing, I needed to make two motor pods that could be rubber banded in place. I built these pods from, you guessed it, some more balsa wood. But where the motors attach is a big weak point. So to avoid the motors being ripped from the balsa wood, I made some extremely strong 3D printed bulkheads that would be a much stronger mount for the motors. I printed these out from standard PLA on my new favorite 3D printers, my Bamboo Lab P2S's, and within 30 minutes, I went from CAD model to these physical parts that could be firmly glued onto the pods. With the pods finished with all of their electronics, I could attach them with rubber bands onto the wing. This would make it easy to adjust their position higher or lower between flights to find the perfect position for that thrust angle. We were nearly ready for another test flight. Hopefully it would fly first time and we wouldn't have any disasters. The test day dawned with a slight breeze, which I thought wouldn't be an issue. So we set the plane up in the big test field next to the workshop and got prepared for the first flight. This was going to be much harder to launch while holding an RC controller. So I asked my friend and longtime helper of the channel, Mike, to lend a hand. OK, Mike, what's your sketch factor analysis for this flight? What does that mean? One to ten, how likely do you think it's going to work? A nine. Wow. Yeah, that is that's way more than me. So this was it, the first flight attempt of the giant circle plane. The plane would rely on very simple controls to fly with no control surfaces, just using the motors to climb and descend. So I hoped I'd got the thrust line correct. Ready? Yep. Immediately, we found an issue. The plane was now really top heavy with the added mass of the motors and difficult to keep upright in the gusty wind. Abort. Abort. I got it, I got it. Just use the face. Oh, we decided to have one more go with myself steadying the top heavy wing, could we finally get it to fly? OK. Yeah, come on. Oh, disaster. After a successful launch, I throttled up the motors only to find out that the thrust line was way too high, pitching the nose down. As soon as I throttled up at that moment, there was nothing I could do. And the plane smashed into the ground with a gut wrenching crunch. The main wing was completely ruined, with both spars being snapped clean in half. It would be incredibly difficult to repair this in a strong way. This was a massive setback. And my fears about the fragile balsa wood had come true. Had I built the plane from the wrong material? All we could do was head back to base and figure out how to fix this aircraft so it could be launched easier and controlled better when in the air. Going back to the drawing board, I decided we would rebuild this plane using parts that survived the crash. First, I would reuse the surviving rear wing as the new main wing. It was a bit smaller, but should still make plenty of lift. Next, I would build a conventional tail on the aircraft so that we could steer the plane with control surfaces instead of relying on throttling the motors. Balsa was potentially the wrong material for this experimental project. But if we could get this plane flying instead of nosing into the ground, it should perform very nicely once in the air. After a day or so of rebuilding, everything was back together. The motors have been lowered, so the thrust line wouldn't be so high. And now hopefully the plane should be trimmed correctly. Certainly got some power. I really wanted to see this giant RC Circle plane flying to see how it compared to a normal winged plane. Surely we could get it in the air this time. Yeah, I'm excited. Let's go. Come on, let's get a good flight. Carefully, I raised the plane into the air. All I needed was one good hand launch and the plane should soar away. You ready? Disaster again. The plane had throttled up and gone straight into the ground. As I throttled up, the plane had pitched down, indicating that the thrust line was still way too high. I pulled up, but the elevator wasn't powerful enough to bring the nose up. Our second balsa wood wing was destroyed. Why did I build this with balsa wood? OK, walk of shame time. It's completely wrecked. Yeah, I don't think that balsa wood was the best idea in hindsight. It's nice and light and everything, but it's just so fragile for this kind of experimentation. I'm absolutely gutted. So that was, yeah, I was really hoping we were going to see it soar into the heavens today, but alas. Right. There was only one thing left to do. I would get rid of the broken balsa wood wing and instead build a much simpler foam and aluminium wing. This would be much more flexible, which would be better for absorbing the impacts of those heavy landings and allow the plane to survive long enough to adjust the motors position. After last time, I now have very low expectations. The wind was blowing very hard and the wing seemed to be way too floppy. Oh, so windy. If we didn't see any improvement now, I might have to write off this entire project as a complete failure and move on to something else. So obviously, this foam wing is way more flexible than the previous balsa wood one. That should help when it comes to landing. So it should be a bit more resilient. But it does introduce some new problems, like that the motors will be twisting slightly when this wing twists. But I'm hoping that basically it will counteract itself. I kind of need to just see what will happen and write this off as an idea. If it doesn't work. The wing was wobbling all over the place. Surely this wasn't going to work, was it? OK, ready? Come on. Oh, no. Oh, well, it's working a bit. Come on. There we go. Right, let's get it a bit higher than that. The wing is going all over the place, but we're in the air. Whoa. Somehow the plane was in the air. It was flying and managing to be fairly controllable. The wing was elongating and flexing around all over the place, but somehow it still had enough lift to fly. It looks so odd. Just like the small rubber powered model, the giant circle plane was flying great in the wind and I was able to easily control it around the field. The only issue was that the wing looked like it was about to break at any moment. All right, maybe I should put it down. Oh, yes. Touchdown. That was certainly the most bouncy landing I've ever done. Well, I think that proves that a circular wing works, but definitely wasn't that structurally sound. Clearly, that wing was way too floppy. The aluminium wasn't keeping it straight at all, but it's in one piece still. And yeah, I think we can we can improve it. Let's go and see if there's any damage. The wing is actually still together. Oh, man, I think that if we put a like a strut along here, it would work way better. We weren't finished with this project quite yet. The aircraft had proved a circle wing plane could fly, but it hadn't worked that well. If I can make some small improvements based on that test flight, we might actually end up with a really great flying aircraft. So we've got the aeroplane modified now. We've now got an actual strut in the middle so that that will stop the wing expanding outwards. We've also got the motors installed on the fuselage. So they were actually connected on this mount here. So that will stop them wiggling around. And yeah, with the wing restrained and the motors fixed in place, we should have a much more rigid and efficient aeroplane. With the plane once again carried out to the test field, it was time for the final test flight. This time, everyone who'd been involved in the project was there to watch, along with one extra, as we'd also been joined by Joe, who'd been keen to see one of my projects actually work. Even the local cows were interested. The wind was blowing, but I was confident in the aircraft. Everything we'd learnt up to this point had shown that this was going to be a good flight. I just needed to not mess anything up. With everything powered on and the cameras rolling, I lifted the plane into its launching position and got ready. I powered the motors up and went for it. Yes, come on! That is working way better than it was before. Fantastic. Oh, it's actually working really well. Oh, that is flying beautifully. Oh, let's go. With the wing being less flexible, the plane was now flying beautifully. The Giant Circle plane was able to cruise along with a perfect amount of control. There's certainly an improvement on our end. I could now finally get a feel for how the aircraft was flying. It felt just like a normal plane, but with much more stability on the roll axis. This meant it flew far better in the wind than I would have expected for such a large aircraft. Watch out, everyone. Let's go. All right, I think we should probably land it. After a few minutes, the plane's small batteries were running low, so it was time to bring it down without breaking it. Here we go. Oh, yes, high five, everyone. Yes, nice. Finally did it, finally did it. Yes. The plane had safely landed and it had worked spectacularly. Now all we had to do was go and inspect it for damage. Brilliant. Yeah, everything's intact. The wing held up. This really helped. And yeah, it was it was definitely very controllable, even though it's got such a narrow wing. I mean, it's crazy how well that flew. Circular wings, they might be the future. Throughout this project, I'd learned a massive amount about circular winged aircraft. We'd done a whole load of trial and error and in the end learned that circular wings might actually be quite a good idea, despite a few drawbacks. Oh, they're still quite top heavy, these things. That is the one problem. Make sure to click the subscribe button down below and also check out the new kits that we have available on the Project Air store. So, yeah, we now make kits and these can help you learn about aeroplanes through building them yourself. These kits are made in collaboration with the Vintage Model Company, and we've even just released a new one based on the circle plane in this video. So you can actually build a circle plane at home yourself. There are also build video guides on the Project Air second channel so that you can learn how to build a kit with me showing you how to put everything together. And in those videos, I also show you how to launch the planes and trim them out to get the longest flight times possible. It's really exciting to be able to announce this to you all. And thank you very much for supporting Project Air over the years so that we can be at this point where manufacturing model kits is actually possible. If you've got to this point of this video, I'm sure you'll enjoy this video next. So click on this one and I will see you on the next video. See you later.