I personally love duct tape. My bicycle is basically made 99% from duct tape by now and I use it when I go fishing shrimps by the river, it works better than rubber boots or military spats
I'm impressed by how condensed this video is, I kinda enjoy long videos but some like this are really fun to watch and also pretty accesible to new viewers, anyway, great video!
The original plane they built was amazing for it time. 20mph it would fly it. Just shows you when you put your mind to things anything is possible. Cheers for sharing Tom good work.
I'm thinking it's largely a scale issue. Plenty of aerodynamic devices work at some sizes but not others. Planes like the Antonov An-72 and the Boeing YC-14 mount jet engines over the wings for STOL performance, so I think there's something to using to help lift. Wikipedia says that the Coandă effect doesn't exist in totally laminar flow, so it makes some sense that the higher Reynolds numbers involved with full scale aircraft make it more prominent.
With the props at the trailing edge, it draws the air over the airfoil more cleanly (think windtunnel). With the props at the leading edge, the wind turbulence decreases the efficiency of the channel. At least, thats my theory.
The airflow from the prop will be so turbulent that the wing would have a huge drop in efficiency. One of the reasons this works is that the channel increases air flow in comparison to the free stream - like a ducted fan. the velocity aft of the prop may be slightly higher, but I'd think it wouldn't be too at significant
My question is what would be the difference between a low-pitch/high RPM prop vs a high-pitch/low RPM prop. Seems like there could be a good case for either, but I have to imagine one would be better for this type of application. Tom used direct drive (not sure of the pitch), and I used a geared system on my micro version (so definitely slower RPM), and comparing the two, I seemed to gain more low-speed lift, but theres a lot of other factors involved. "More testing required" as they say...
The Chanel produces lift in 180 degrees, which does not all go towards lifting the airplane. It probably makes your propellers work better but probably doesn’t give you all that much upward lift. You could test the straight wing vs the channel wing with a sensitive scale.
Awesome work Tom, is that depron foam? Where did you get your hands on that? Also, I've noticed on a lot of your VTOL projects you've frankensteined a betaflight controller with a teensy to do your mixing. I've written my own flight control code that runs entirely on teensy 4.0/4.1 with an mpu6050. Let me know if you're interested in getting your hands on that for future projects. My interest is in weird VTOLs too--you beat me to the swashplateless heli!
@@MachineChrist6 Reason I ask about the foam is because depron hasn't been available here in the states in years. Dollar tree is the only option for 5-6mm foamboard it seems
I really like the way you approach old concepts. 3-D printers are a God-send to fast prototyping. Back in my day's we built with wood and cloth, and lot's of time to complete. Now we are in the age of digital flight. Coding these types of aircraft is key to flight. Very soon you will see flying a UFO ha ha a real-dead bird. Plans to build one has been completed and tested. Yes it sounds sick, I agree but never-less it has been done. Dead bird stuffed with servo's and head with a prop, legless with wheels. God created a perfect drone. Keep it up and never give up.
Fantastic that there are people like you willing to put time and expense into testing a concept. My own evaluation of this concept, which Pazmany introduced me to in the early 1980s, is that it can provide very high lift, but in a way that is not usable because there is no provision for control. Your experiment showed the large pitching moments produced, which can't be overcome until the machine is moving fast enough for the control surfaces to have an effect. Possible remedy is to add a cascade of control surfaces behind or just ahead of each propeller, but this will cost drag, and will only be necessary during a very short part of the flight.
This is gonna sound crazy, but what if you made a channel wing quadcopter? Have four sets of motor/wing, and have one set opposed to the other set. The thrust should cancel out, but would produce lift. Not completely sure on the control scheme, though. Yaw and roll would both be simple, as the would be no net thrust in any one direction, but pitch would be difficult due to the fact that you would need to reduce lift on one side, but now that same side is providing less thrust to counter the other side's thrust, leading to forwards/backwards movement of the craft. Maybe have a single extra motor, or maybe a pair of motors, without a channel wing, dedicated purely to pitch? If they had no response to altitude control, it would still be a good proof of the ability of a channel wing.
It has advantages, easy convertion of a vtol propeller extenting out of the wing and back. Won't change the drag as much unless you can completly reduce the axel bar to the propellars. to near thin invisable
I'm thinking that the semi circles opened up to conventional straight airfoil surface might produce more lift either with motors on or off. If the semi circle is about 4 inches/10 cm across then the increase in total wing length would be around 1 foot/30 cm. That's nothing to ignore.
Now I need to check the other video you did, because a pusher configuration in the duct doesn't really makes sense for me. Instinctively I thought having the propellers up front pushing all that high speed air over the duct would be more efficient, I may be wrong though. But one remarkable thing I want to mention is how incredibly skilled you are now. I've been into this channel for quite a while now and comparing the first ones to now, it's just amazing how much you evolved and how great your designs became. Please keep up the good work man, I love your videos and I love science!
I think there's a combination of factors here they resulted in a less than impressive result. Firstly, the spar is creating significant turbulence before it reaches the propellers, surely this would reduce lift and efficiency. Second, with the propellers mounted so far back behind the channel, I suspect very little lift is being generated at the front of the channel, where it's needed most. A theory that seems to be supported by the fact that without the dihedral outer wings, it had almost no lift on its own. I feel like they need to be smaller to fit inside the channel, if not half way, then at least inside the trailing edge.
3D printing nowadays is very accessible. Of course there is a bit to learn but once you get the basics, as long as you stick with the usual materials, you should be fine.
Multi engined planes definitely benefit from induced lift. The channel wings lift isn't directed downward but normal to the surface. Perhaps combining the shape of the channel so more lift is directed downward would result in better results. A good way to discover how significant induced drag is to fly the XL 450 and in plane mode apply yaw command. This cause the inboard motor to slow just as the wing begins to slow itself. It pretty much guarantees a snap. Be prepared to shift to hover mode to recover. Like your videos. There is no better way to affirm an idea or principal than actually doing it. Like your videos.
I've lost the count of times when something doesn't behave very stable and Tom just goes "give it a full boot before it can get out of hand" and then destroys what he's trying to fly.
Tom: Your videos are the most interesting and original I've seen on YT. You are clearly a highly trained physicist/engineer/experimentalist. My question is this: Are you able support your tools, materials, house on prime English real estate, groceries, beer and the Beeb, all on earnings from You Tube, and if so, how do I get started? I admire and envy your seemingly idyllic lifestyle. And I love your videos! Thanks a million!
Planes fly from a combination of air directed downward by the angle of attack of the wing and lift from the airfoil. I think the airfoil is a minor efficiency enhancement compared to the wing angle of attack, which is why stunt planes have no trouble flying upside down, especially at low speeds. If this is true, then you would get much more vertical thrust blowing air against the underside of a wing, ie vectored thrust, just like VTOL aircraft use.
In drawing airflow over an aerofoil to produce lift at low aircraft velocities, I think much the same thing has already been created in the form of the Osprey V22 tilt rotor. While it's main attribute is to use the tilt rotors to hover, the wing itself produces extraordinary lift from a stubby wing section by means of the two Alison turboprop engines which force air over the wing and trailing edge flaperon to produce lift even before the aircraft has moved forward. In flight, the aircraft is brought to a hover by slowly rotating the engine nacelles to a vertical axis to produce lift, while the transition is assisted by the flaperon which provides additional lift to assist the wing as forward speed deteriorates.
This is not true; tilt-rotors do not tilt the wings and they are a source of reduction of hover performance caused by wing - rotor flow interactions, such as wing download, wing fountain flow and other flow perturbations. A bit better are the tilt wing designs, e.g. Canadair CL-84, but the single wing advantage is not stalling at any angle. In pure hover, the wing is worse than "dead weight" as being a source of surface drag, and decreasing hovering effectiveness, the "figure of merit"
@@aliptera If you were an actual qualified aircraft engineer, as am I, you would be able to discern the fact that I stated "rotating the engine nacelles" which are the structures at the wingtips (not the wings themselves) which do the rotating while the wing (mainplane) remains fixed and stationary. The point that I made was that the two designs each cause air to move front to rear by the use of propellers, Tom's model, by drawing airflow while the V22 achieved it by pushing airflow whilst in a stationary manner, and also in normal forward flight. Tom's model was designed to achieve both lift and thrust while the V22 could only achieve realistic and useful lift by rotating the engines to a vertical axis.
Great work! The model (probably the wheels and tape colour) reminded me of the Super Draco bush plane. In an unrelated train of thought, I imagined dissecting an octuple prop drone by scavenging two drone motor nacelles. These might serve as a useful source for further two-engine (but four-prop) channel wing experiments somehow (with the non laminar prop extended on a boom? that’s crazy talk). This would involve a ridiculous amount of reprogramming to get back to autonomous stability perhaps, but if you were willing to ignore that, the hardware might get you closer to controlling pitch (turn?) by throttle. Now I have a vision of a Draco-like bush plane with radial engines and a bubble canopy nose...Thanks again for the thought-provoking video.
Glad to see someone looking at some of the odd wing designs. Another odd one from the 20/30's I think was called a void wing, with a cavity involved on the top side of the plane, seemed odd and interesting, but cannot find anything on it now.
@@SuperBialyWilk Yes, every click on a website has an extra delay. Some actions are still responsive due to local caching but you will notice it for sure. Once you are below 50 ms or so you're fine. Also bandwidth is a product of link capacity and delay (the bandwidth-delay product), so in effect you are also decreasing your download and upload speed.
@@kevintieman3616 That's not true. Packet loss affects the download speed. Usually a longer distance traveled result in more packet loss but it's not in itself connected to ping. Ping is only the time delay for a packet to get to a destination and back. You can still send all your packets one after another without getting a reply for the first one back. The only time you notice a delay is with the SYN - SYN ACK - ACK. Like you said about the websites taking longer. However 50 ping vs 150 ping is only a difference of a 1/10th of a second. Something you would barely notice. So in conclusion the ping is NOT what causes most of your experienced delay while using a VPN. It's packet loss and bandwidth. For each packet lost you have to send a new one (assuming TCP/IP) when sending a new one that packet takes an additional 150ms to get there and a response to come back. That is the experienced delay.
@@SonnyKnutson Your conclusion is not correct, delay is a key part of what determines your download speed and internet experience. Looking at the Bandwidth Delay Product (BDP (bytes) = total_available_bandwidth (KBytes/sec) x round_trip_time (ms)), which determines your actual download speed, doubling the delay effectively halves the download speed. Your application might try to increase the tcp window size to keep the download speed up, at some point the inevitable packet loss will have a much more dramatic effect crippling your download speed. For example, if you have crappy wifi your similar crappy internet experience will be amplified with the amount of delay you add (with a vpn for example).
@@SonnyKnutson Your assesment about 1/10th of a second would be correct if websites were served as a single files but any modern website will load html first, then stylesheets and scripts, image files referenced by the stylesheets and scripts. So if you look at total pageload time the delay would be the sum of all requests which can't be parallelized
Here is an idea for you - Low speed wing stall should be relatively small as long as the props are running to counter it. Therefore you should be able to tilt the entire wing and motor upward during take off and landing for low speed. Think MV-22 Osprey. Maybe not a full 90 deg but 30 to 45 to start.
Love your approach to engineering. In regards to producing lift from propulsion method, i.e. prop wash as a source of air flow over a lifting surface. May I suggest you look into tractor prop/delta wing arrangement.. Works wonders for me. Best regards.
Hello the lift is almost zero on the rounded area of the wing. this comes from the suction of the flow by the propellers. The wind no longer hits the leading edge. if the helises were forward and of a diameter greater than the rounded area, the flow would be projected onto the leading edge of this area. the lift would therefore be maximum. If my English is bad it's normal I'm French I apologize
As a helicopter pilot I can attest that you don't need a fixed wing to fly. You just need a pressure differential (or if you're a DJI or a Harrier fan, ducted fans pointed down). Fundamentally all require a SIGNIFICANT amount of power to achieve lift. That power is also unavailable for thrust, and will deplete the fuel source be it jet fuel (Harrier) or batteries (DJI) or AVGas (what I fly). When you add a fixed-wing lift mechanism (and your elevator qualifies as well) so long as you can keep it light and large you win the aerofoil advantage by getting "free" lift. Of course it's not free. It sits on the ground quite heavily. You need airspeed to get that lift... which is why any discussion of a "low speed" or "no speed" aerofoil has its limits. Yes, you can put a pusher prop on a plain on a treadmill... but will it fly? Well the general answer is no... but if you put the prop so the air flows over the aerofoils it WILL fly over the treadmill, with possibly a 0 knot groundspeed. That would be an interesting experiment. Thanks for your videos - always appreciated! Ehud Gavron Tucson, Arizona USA FAA Commercial Helicopter Pilot
I think that if you put the prop on the front of the wing there will be a lot more air flow over the wing from the venturi effect, so then it will have a lot more lift with a slower prop speed.
Test with regular wing and read the amperage while flying for 2-8 minutes dual motors, then try this design for the same amount of time, this will give you an efficiency reading between the two
Was going to suggest this idea, you beat me to it. Obviously you would use the same motors and propellers. Not sure it would make sense to add weight to the conventional wing so that both versions have the same weight - the channel wing is inherently heavier - though the weight ratio might be different with the materials used in this model, from the real deal. Perhaps it would be worthwhile trying to get closer to the dynamics of a full sized aircraft: for instance, I don't think the engines on a real aircraft would be powerful enough to make it jump around like that (except fighter planes maybe). Anyway it makes a fascinating video, thanks!
Hey awesome work! I love the types of builds you make and explore. One thing though, the type of wing you made would have "polyhedral" wing surfaces, or more specifically "tip dihedral". Just wanted to offer some knowledge I can share! Technically you are right, dihedral is correct, but it is not totally descriptive of the type of wing you made. Cheers!
I recognise the weight issue. But it sounds like you get significantly better handling with rudder control. A flat concrete surface would reduce the rolling resistance of the grass & may reduce the V1. Allowing a controlled takeoff / better balance of the plane. Attaching a long string from the back of the plane to a measure. May permit you to keep the aircraft stationary & measure thrust required for VTOL. Very interesting, great work.
@@jamesmilton3490 Oh I'm majoring in aerospace engineering so I know these theories, I was just wondering where you got the exact parameters of the parts i.e drag coefficient of the wing, size of the spar and wing, etc.
Is there any chance you could rerun this video but without the curved sections under the propellors to see does it lift anyway with the remnants of the wing and the propellors on their own
If you're familiar with the Dyson "air multiplier" "fanless" fans have a look at how the ring shaped airfoil is designed. There's at intake fan that flows air out over the inner surface of the ring that I think would make an interesting design for a blown airfoil.
04:19 This scene shows that your plane flies just by the power of the engines (logical, when you think about the power to weight ratio). Aerodynamics are neglectable. With these engines you could fly a shoebox the same way.
Here's a daft idea: What would happen if you had two engines and ducts on each wing and reversed half of the engines to slow down instead of powering down? That way you could keep the airflow over the wings high without providing much (or any) forward thrust. (Yes, you would probably also produce insane turbulence around each wing.)
Tom, you said you thought it was tail heavy so you moved the battery forward. But then you said thrust pitches the aircraft up so that suggests it wasn’t tail heavy to begin with. A nose heavy plane won’t glide as well or fly at as low speed as a balanced plane. Maybe the cg and pitching is worth exploring some more. Just 20mph for that plane at the beginning seems amazingly slow. I would estimate a normal plane like that would stall somewhere above 60mph.
Was looking for your first video on this and only found this one after skimming your videos for a bit. Also found an article where someone named Bob Englar tried to improve the design it seems. It appears his lab further increased the "considerable lift" using compressed air blown over the channel in a particular fashion. It also eliminated the need for landing at high angles of attack and provided pneumatic compensation in the event of losing an engine. The article is called That Extra Little Lift by Tim Wright and published in May 2007 by the Smithsonian Magazine. Figure that should be enough to find it, and it would take more time than I presently have to properly cite it. Figure it would be a great read if you ever intend to return to this project, perhaps with you air powered engine :D
If I am not mistaken, for greater effect from the wing channel, it was necessary to install the screws in the place of the greatest thickness of the profile
Tom, leading edge prop. To get the highest slipstream and greatest narrowing you need the nacelles in front of the prop and the prop at the leading edge
Hey man, if you want a strong structure with a light 3D printed frame, print out your piece then coat it in truck bed liner, its a little more heavy but each layer adds much needed structural integrity! 👍😁
Since the props are in the back of the channel, you would get a lot of airflow coming in that wouldn't flow over the channel unless the plane is flying forward which negates the point of the channels. What about if you put the props at the leading edge of the channel and the kinetic energy of the air coming off the props would force it over the channel?
If thrust off a wing has any similarities with buoyancy (this I don’t know as I’m a boat guy) then the lift acts at 90 degrees to the surface of the airfoil. If this is the case than only the very bottom of the channel is producing true lift and all other points of the channel produce lift at a tangent to straight up, with the sides of the channel producing an opposite lift force to each other but none of it being a lifting component. This would explain why the lift generated has to be so high, as the contributing lift by the channel decreases as you move around the radius from the bottom.
The low performance is due to the position of the prop. It should optimally be at the crown of the wing cord and sweep within a millimater of the surface for maximum low pressure. If you want to have a truly impressive performance you make a second wing hoop to sit over the prop turning the prop into a thrust nacell for high speed flight. When this upper surface slides back beyond the prop and angles down that surface becomes a vectored thrust surface producing additional lift. So with this upper surface retracted aft you get the lift from the Custer wing plus the vectored lift from that surface giving you high lift low speed high drag. Moving the upper surface forward transitions the combination to high thrust high speed low lift low drag. The problem with the Custer wing was always that the feature that gave it high lift limited its speed performance as with all STOL configurations. This simple transition configuration solves that problem to give a VSTOL capability which transitions to a high speed configuration which should give you 200kph performance.
I have been thinking a lot about the channel wing concept lately. I would like to try a similar test but adding a down turned duct or set of variable vanes after the prop to direct the propwash downward as well. This would increase the lift without increasing the forward thrust. If they were efficient enough you could theoretically hover. I think in this test you may not have been able to see much effect of the channel wing on landing as you had to increase throttle to gain the extra lift which also increased your airspeed. If you could direct the propwash downward you could increase throttle without increasing airspeed which would allow for slower flight. Nonetheless this was great to watch as well as your previous video test of the channel wing on the test bench.
The pitch up on power looked a lot like the lift is tied to the throttle. I think if tom raises the angle of attack of the wing section itself independently of the channels it would allow some more conclusive results as the whole craft would fly slower and the throttle would act more like flaps. Conversely you could add symmetrical sections at the outer tips and angle the thrust line down slightly. Real planes with blown wings rely on throttle control during landing but have shorter wings than similarly sized aircraft.
I imagined this myself many years ago. My idea evolved into a wing that contains numerous ducted fans built into the wings. It may need to scale up to a life sized plane to fit the fans into the wing thickness.
I wonder, would it be possible to use channel wings to steer a quad-copter drone? What I'm thinking is, take a drone with auto-hover capabilities, then fit a channel-wing above each propellor on a rotating mount. Then, if you want to, say, go left, rotate the channel wings so that they are all on the right side of their respective propellor, producing lift pushing the drone left. Obviously, it would be much more complex, and probably less effective, than just varying the throttles on the motors to pitch/roll the drone, but I think it would be an interesting experiment.
Verynice design truly inspiring we need more of these full scale like to see this combined to the u 2 spy plane with dual scam jets or vector plates behind the prop
I would love to see a tilt wing, vertical takeoff plane. Also would love to see a tail-sitter that didn't need to tilt the wing, but could be essentially the same design.
Increase lift and reduce drag by moving the camber to midwing and decrease drag and increase lift more by dimpling the wing surface in the channel like a Golf Ball surface.
that could change if you use funnels instead. and by using funnels the location of the propeller is important. a funnel will increase propeller back pressure at least in theory
I think the motor should be in front of the curved wing and slightly larger propellers than the Curve of the Wings and don't forget you need a few degrees of down thrust to keep the plane from popping up in the nose
My wife says: "If it can't be fixed with duct tape, there is something wrong with it." LOL
"like our marriage"
You chose well my man..you chose well. I hope she has a healthy respect for wd40 too...
*F L E X T A P E*
Ah, but she’s only partially correct. Never forget wd 40
You just don’t have enough duct tape
I bet channel wing aircraft are hilarious when they fly upside down
Lewis Johson
😟
Ah yes dropping like a shitty drone
I'm lovin' it
Hopefully the next video is a submarine
My prediction is it would fly normally.
I was waiting for this video with such excitement!!!!! Thank you for making it!!!
LOL me too!
True dat
Same!
Stop self promo
@@sonnywilliams2532 I don't get it
The disgust look when he said "duck tape" is absolutely British. +1 would laugh again.
I personally love duct tape. My bicycle is basically made 99% from duct tape by now and I use it when I go fishing shrimps by the river, it works better than rubber boots or military spats
duct* tape.
@@DieselRamcharger there's also a brand called duck tape
@@Momo_Kawashima i know, its a brand of duct tape....Mallards Lives Matter.
@@DieselRamcharger the original name was duck tape
I'm impressed by how condensed this video is, I kinda enjoy long videos but some like this are really fun to watch and also pretty accesible to new viewers, anyway, great video!
The original plane they built was amazing for it time. 20mph it would fly it. Just shows you when you put your mind to things anything is possible. Cheers for sharing Tom good work.
I have done lots of research into the barrel wing. Amazing stability at low air speeds. Need counter rotating props for low speed control.
I'm thinking it's largely a scale issue. Plenty of aerodynamic devices work at some sizes but not others. Planes like the Antonov An-72 and the Boeing YC-14 mount jet engines over the wings for STOL performance, so I think there's something to using to help lift. Wikipedia says that the Coandă effect doesn't exist in totally laminar flow, so it makes some sense that the higher Reynolds numbers involved with full scale aircraft make it more prominent.
Finally a proper scientific conclusion! It’s all fluid dynamics man…
I would suggest using an impeller because it can pull air over the wing and then for forward thrust, you could use a propeller.
Any difference in lift by having the motors push air over the wings, vs pulling air?
I think it worth to test the later. The High-speed air passes the surface will provide more lift.
Ya bro there is a huge difference
With the props at the trailing edge, it draws the air over the airfoil more cleanly (think windtunnel). With the props at the leading edge, the wind turbulence decreases the efficiency of the channel. At least, thats my theory.
The airflow from the prop will be so turbulent that the wing would have a huge drop in efficiency.
One of the reasons this works is that the channel increases air flow in comparison to the free stream - like a ducted fan. the velocity aft of the prop may be slightly higher, but I'd think it wouldn't be too at significant
My question is what would be the difference between a low-pitch/high RPM prop vs a high-pitch/low RPM prop. Seems like there could be a good case for either, but I have to imagine one would be better for this type of application.
Tom used direct drive (not sure of the pitch), and I used a geared system on my micro version (so definitely slower RPM), and comparing the two, I seemed to gain more low-speed lift, but theres a lot of other factors involved. "More testing required" as they say...
The Chanel produces lift in 180 degrees, which does not all go towards lifting the airplane. It probably makes your propellers work better but probably doesn’t give you all that much upward lift. You could test the straight wing vs the channel wing with a sensitive scale.
Awesome work Tom, is that depron foam? Where did you get your hands on that?
Also, I've noticed on a lot of your VTOL projects you've frankensteined a betaflight controller with a teensy to do your mixing. I've written my own flight control code that runs entirely on teensy 4.0/4.1 with an mpu6050. Let me know if you're interested in getting your hands on that for future projects. My interest is in weird VTOLs too--you beat me to the swashplateless heli!
With my foam board planes I use the dollar tree foam board. Super cheap. ($1) and is strong when you use the packing tape on the outside.
@@MachineChrist6 Reason I ask about the foam is because depron hasn't been available here in the states in years. Dollar tree is the only option for 5-6mm foamboard it seems
@@NicholasRehm I had no idea it wasnt avaliable here.
@@MachineChrist6 Yep unfortunately its really only available in massive industrial sized spools now :(
Depron is back or coming back!! I've seen posts from the guy on Facebook. www.rcdepron.com/
I really like the way you approach old concepts. 3-D printers are a God-send to fast prototyping. Back in my day's we built with wood and cloth, and lot's of time to complete. Now we are in the age of digital flight. Coding these types of aircraft is key to flight. Very soon you will see flying a UFO ha ha a real-dead bird. Plans to build one has been completed and tested. Yes it sounds sick, I agree but never-less it has been done. Dead bird stuffed with servo's and head with a prop, legless with wheels. God created a perfect drone. Keep it up and never give up.
Fantastic that there are people like you willing to put time and expense into testing a concept. My own evaluation of this concept, which Pazmany introduced me to in the early 1980s, is that it can provide very high lift, but in a way that is not usable because there is no provision for control. Your experiment showed the large pitching moments produced, which can't be overcome until the machine is moving fast enough for the control surfaces to have an effect. Possible remedy is to add a cascade of control surfaces behind or just ahead of each propeller, but this will cost drag, and will only be necessary during a very short part of the flight.
I was literally just about to make one of these
Do it, definitely worth it! Micro version: ua-cam.com/video/ZnsGgwKLxcs/v-deo.html
I wish I had the tools right there so I could do something like that
This is gonna sound crazy, but what if you made a channel wing quadcopter?
Have four sets of motor/wing, and have one set opposed to the other set. The thrust should cancel out, but would produce lift. Not completely sure on the control scheme, though. Yaw and roll would both be simple, as the would be no net thrust in any one direction, but pitch would be difficult due to the fact that you would need to reduce lift on one side, but now that same side is providing less thrust to counter the other side's thrust, leading to forwards/backwards movement of the craft. Maybe have a single extra motor, or maybe a pair of motors, without a channel wing, dedicated purely to pitch? If they had no response to altitude control, it would still be a good proof of the ability of a channel wing.
Eric The Epic he could use reaction wheels for pitch...
It has advantages, easy convertion of a vtol propeller extenting out of the wing and back. Won't change the drag as much unless you can completly reduce the axel bar to the propellars. to near thin invisable
I'm thinking that the semi circles opened up to conventional straight airfoil surface might produce more lift either with motors on or off. If the semi circle is about 4 inches/10 cm across then the increase in total wing length would be around 1 foot/30 cm. That's nothing to ignore.
Now I need to check the other video you did, because a pusher configuration in the duct doesn't really makes sense for me. Instinctively I thought having the propellers up front pushing all that high speed air over the duct would be more efficient, I may be wrong though. But one remarkable thing I want to mention is how incredibly skilled you are now. I've been into this channel for quite a while now and comparing the first ones to now, it's just amazing how much you evolved and how great your designs became. Please keep up the good work man, I love your videos and I love science!
wow had never heard of LW-PLA. here i am just struggling with abs since it's less dense and still making pretty heavy parts.
It's an interesting material. CNC Kitchen has a video on it if you want to learn more about its properties :) ua-cam.com/video/2tmgzwgi2UI/v-deo.html
vase mode PTEG...
I think there's a combination of factors here they resulted in a less than impressive result.
Firstly, the spar is creating significant turbulence before it reaches the propellers, surely this would reduce lift and efficiency.
Second, with the propellers mounted so far back behind the channel, I suspect very little lift is being generated at the front of the channel, where it's needed most. A theory that seems to be supported by the fact that without the dihedral outer wings, it had almost no lift on its own. I feel like they need to be smaller to fit inside the channel, if not half way, then at least inside the trailing edge.
Wish I had a 3d printer. And the ability to use one. I'm so technologically illiterate!
This is such an Awesome design
3D printing nowadays is very accessible. Of course there is a bit to learn but once you get the basics, as long as you stick with the usual materials, you should be fine.
The Longer LK4 or Ender 3 is a great start to printing and they are around $200
@@joecarpino Im about to buy one in a few hours! (ender 3)
Daniel Files - Nice!
Thanks for the replys guys.im currently looking into the Ender 3 now
Multi engined planes definitely benefit from induced lift. The channel wings lift isn't directed downward but normal to the surface. Perhaps combining the shape of the channel so more lift is directed downward would result in better results. A good way to discover how significant induced drag is to fly the XL 450 and in plane mode apply yaw command. This cause the inboard motor to slow just as the wing begins to slow itself. It pretty much guarantees a snap. Be prepared to shift to hover mode to recover. Like your videos. There is no better way to affirm an idea or principal than actually doing it. Like your videos.
I've lost the count of times when something doesn't behave very stable and Tom just goes "give it a full boot before it can get out of hand" and then destroys what he's trying to fly.
Tom: Your videos are the most interesting and original I've seen on YT. You are clearly a highly trained physicist/engineer/experimentalist. My question is this: Are you able support your tools, materials, house on prime English real estate, groceries, beer and the Beeb, all on earnings from You Tube, and if so, how do I get started? I admire and envy your seemingly idyllic lifestyle. And I love your videos! Thanks a million!
This guy out here playing ksp in real life. A genius!
Well he is an aerospace engineer
Man it makes Netflix's data look like there are 56 million people watching Canadian Netflix
I knew Mr Custer. He lived in my home town. The channel wing plane was very cool. He was a brilliant man.
Planes fly from a combination of air directed downward by the angle of attack of the wing and lift from the airfoil. I think the airfoil is a minor efficiency enhancement compared to the wing angle of attack, which is why stunt planes have no trouble flying upside down, especially at low speeds. If this is true, then you would get much more vertical thrust blowing air against the underside of a wing, ie vectored thrust, just like VTOL aircraft use.
I always enjoy watching your videos, good to see you again!
In drawing airflow over an aerofoil to produce lift at low aircraft velocities, I think much the same thing has already been created in the form of the Osprey V22 tilt rotor. While it's main attribute is to use the tilt rotors to hover, the wing itself produces extraordinary lift from a stubby wing section by means of the two Alison turboprop engines which force air over the wing and trailing edge flaperon to produce lift even before the aircraft has moved forward. In flight, the aircraft is brought to a hover by slowly rotating the engine nacelles to a vertical axis to produce lift, while the transition is assisted by the flaperon which provides additional lift to assist the wing as forward speed deteriorates.
This is not true; tilt-rotors do not tilt the wings and they are a source of reduction of hover performance caused by wing - rotor flow interactions, such as wing download, wing fountain flow and other flow perturbations. A bit better are the tilt wing designs, e.g. Canadair CL-84, but the single wing advantage is not stalling at any angle. In pure hover, the wing is worse than "dead weight" as being a source of surface drag, and decreasing hovering effectiveness, the "figure of merit"
@@aliptera If you were an actual qualified aircraft engineer, as am I, you would be able to discern the fact that I stated "rotating the engine nacelles" which are the structures at the wingtips (not the wings themselves) which do the rotating while the wing (mainplane) remains fixed and stationary. The point that I made was that the two designs each cause air to move front to rear by the use of propellers, Tom's model, by drawing airflow while the V22 achieved it by pushing airflow whilst in a stationary manner, and also in normal forward flight. Tom's model was designed to achieve both lift and thrust while the V22 could only achieve realistic and useful lift by rotating the engines to a vertical axis.
Very impressive slow motion shots. They get better and better.
Is the centre of thrust too low causing the pitch up, preventing the effect from really working?
Also the ratio between the volume of the channel, the wings and aircraft body and the depth of the channel is very different from the original.
You can tell these recent videos were filmed during the lock down XD. Immaculate garden, people at home.
Great work! The model (probably the wheels and tape colour) reminded me of the Super Draco bush plane. In an unrelated train of thought, I imagined dissecting an octuple prop drone by scavenging two drone motor nacelles. These might serve as a useful source for further two-engine (but four-prop) channel wing experiments somehow (with the non laminar prop extended on a boom? that’s crazy talk). This would involve a ridiculous amount of reprogramming to get back to autonomous stability perhaps, but if you were willing to ignore that, the hardware might get you closer to controlling pitch (turn?) by throttle.
Now I have a vision of a Draco-like bush plane with radial engines and a bubble canopy nose...Thanks again for the thought-provoking video.
Very interesting. I had never heard of that type of wing.
bro we really need to get u to 1 mil subs u deserve it bro !! keep it up
5:54 the way he looked at camera...had me weak
Glad to see someone looking at some of the odd wing designs. Another odd one from the 20/30's I think was called a void wing, with a cavity involved on the top side of the plane, seemed odd and interesting, but cannot find anything on it now.
ExpressVPN when you want a ridiculous high ping! 5:54
Would that make a difference in anything except gaming?
@@SuperBialyWilk Yes, every click on a website has an extra delay. Some actions are still responsive due to local caching but you will notice it for sure. Once you are below 50 ms or so you're fine. Also bandwidth is a product of link capacity and delay (the bandwidth-delay product), so in effect you are also decreasing your download and upload speed.
@@kevintieman3616 That's not true. Packet loss affects the download speed. Usually a longer distance traveled result in more packet loss but it's not in itself connected to ping. Ping is only the time delay for a packet to get to a destination and back. You can still send all your packets one after another without getting a reply for the first one back.
The only time you notice a delay is with the SYN - SYN ACK - ACK. Like you said about the websites taking longer. However 50 ping vs 150 ping is only a difference of a 1/10th of a second. Something you would barely notice.
So in conclusion the ping is NOT what causes most of your experienced delay while using a VPN. It's packet loss and bandwidth.
For each packet lost you have to send a new one (assuming TCP/IP) when sending a new one that packet takes an additional 150ms to get there and a response to come back. That is the experienced delay.
@@SonnyKnutson Your conclusion is not correct, delay is a key part of what determines your download speed and internet experience. Looking at the Bandwidth Delay Product (BDP (bytes) = total_available_bandwidth (KBytes/sec) x round_trip_time (ms)), which determines your actual download speed, doubling the delay effectively halves the download speed. Your application might try to increase the tcp window size to keep the download speed up, at some point the inevitable packet loss will have a much more dramatic effect crippling your download speed. For example, if you have crappy wifi your similar crappy internet experience will be amplified with the amount of delay you add (with a vpn for example).
@@SonnyKnutson Your assesment about 1/10th of a second would be correct if websites were served as a single files but any modern website will load html first, then stylesheets and scripts, image files referenced by the stylesheets and scripts. So if you look at total pageload time the delay would be the sum of all requests which can't be parallelized
I anticipate your videos more than all those I follow!
I think the real winner here for us viewers is that expanding foam filament. Very interesting.
Here is an idea for you - Low speed wing stall should be relatively small as long as the props are running to counter it. Therefore you should be able to tilt the entire wing and motor upward during take off and landing for low speed. Think MV-22 Osprey. Maybe not a full 90 deg but 30 to 45 to start.
@@dodecahedron1 Could Be. Just trying to provide a bit of an example of my thought.
Love your approach to engineering. In regards to producing lift from propulsion method, i.e. prop wash as a source of air flow over a lifting surface. May I suggest you look into tractor prop/delta wing arrangement.. Works wonders for me. Best regards.
Hello
the lift is almost zero on the rounded area of the wing.
this comes from the suction of the flow by the propellers.
The wind no longer hits the leading edge.
if the helises were forward and of a diameter greater than the rounded area, the flow would be projected onto the leading edge of this area.
the lift would therefore be maximum.
If my English is bad it's normal I'm French I apologize
You always get the best ideas
Something that would fit nicely with your "using unusual forms of lift" theme would be the Magnus effect
Now I wanna see that nearly vertical takeoff build!!
As a helicopter pilot I can attest that you don't need a fixed wing to fly. You just need a pressure differential (or if you're a DJI or a Harrier fan, ducted fans pointed down). Fundamentally all require a SIGNIFICANT amount of power to achieve lift. That power is also unavailable for thrust, and will deplete the fuel source be it jet fuel (Harrier) or batteries (DJI) or AVGas (what I fly).
When you add a fixed-wing lift mechanism (and your elevator qualifies as well) so long as you can keep it light and large you win the aerofoil advantage by getting "free" lift. Of course it's not free. It sits on the ground quite heavily. You need airspeed to get that lift... which is why any discussion of a "low speed" or "no speed" aerofoil has its limits.
Yes, you can put a pusher prop on a plain on a treadmill... but will it fly? Well the general answer is no... but if you put the prop so the air flows over the aerofoils it WILL fly over the treadmill, with possibly a 0 knot groundspeed. That would be an interesting experiment.
Thanks for your videos - always appreciated!
Ehud Gavron
Tucson, Arizona USA
FAA Commercial Helicopter Pilot
I think that if you put the prop on the front of the wing there will be a lot more air flow over the wing from the venturi effect, so then it will have a lot more lift with a slower prop speed.
One of the original airplanes is at the Mid Atlantic Air Museum in Reading, PA. It sits outside with its fiberglass channels in bad shape.
Test with regular wing and read the amperage while flying for 2-8 minutes dual motors, then try this design for the same amount of time, this will give you an efficiency reading between the two
Was going to suggest this idea, you beat me to it.
Obviously you would use the same motors and propellers.
Not sure it would make sense to add weight to the conventional wing so that both versions have the same weight - the channel wing is inherently heavier - though the weight ratio might be different with the materials used in this model, from the real deal.
Perhaps it would be worthwhile trying to get closer to the dynamics of a full sized aircraft: for instance, I don't think the engines on a real aircraft would be powerful enough to make it jump around like that (except fighter planes maybe).
Anyway it makes a fascinating video, thanks!
Thanks for not dragging this over 10 minutes..
Hey awesome work! I love the types of builds you make and explore. One thing though, the type of wing you made would have "polyhedral" wing surfaces, or more specifically "tip dihedral". Just wanted to offer some knowledge I can share! Technically you are right, dihedral is correct, but it is not totally descriptive of the type of wing you made. Cheers!
I recognise the weight issue. But it sounds like you get significantly better handling with rudder control.
A flat concrete surface would reduce the rolling resistance of the grass & may reduce the V1. Allowing a controlled takeoff / better balance of the plane.
Attaching a long string from the back of the plane to a measure. May permit you to keep the aircraft stationary & measure thrust required for VTOL.
Very interesting, great work.
By leaving the spar exposed the drag is increased by about 9 times more than if it was covered by an airfoil.
9 times?
@@kurumi394 Watch the experiments in the first six minutes of this video ua-cam.com/video/acySDnGYzVM/v-deo.html Its amazing.
@@jamesmilton3490 Oh I'm majoring in aerospace engineering so I know these theories, I was just wondering where you got the exact parameters of the parts i.e drag coefficient of the wing, size of the spar and wing, etc.
Is there any chance you could rerun this video but without the curved sections under the propellors to see does it lift anyway with the remnants of the wing and the propellors on their own
So many industries want or need light-weighting, I believe foams are going to be big in the future.
If you're familiar with the Dyson "air multiplier" "fanless" fans have a look at how the ring shaped airfoil is designed. There's at intake fan that flows air out over the inner surface of the ring that I think would make an interesting design for a blown airfoil.
04:19 This scene shows that your plane flies just by the power of the engines (logical, when you think about the power to weight ratio). Aerodynamics are neglectable. With these engines you could fly a shoebox the same way.
Here's a daft idea: What would happen if you had two engines and ducts on each wing and reversed half of the engines to slow down instead of powering down? That way you could keep the airflow over the wings high without providing much (or any) forward thrust. (Yes, you would probably also produce insane turbulence around each wing.)
Tom, you said you thought it was tail heavy so you moved the battery forward. But then you said thrust pitches the aircraft up so that suggests it wasn’t tail heavy to begin with. A nose heavy plane won’t glide as well or fly at as low speed as a balanced plane. Maybe the cg and pitching is worth exploring some more. Just 20mph for that plane at the beginning seems amazingly slow. I would estimate a normal plane like that would stall somewhere above 60mph.
Was looking for your first video on this and only found this one after skimming your videos for a bit. Also found an article where someone named Bob Englar tried to improve the design it seems. It appears his lab further increased the "considerable lift" using compressed air blown over the channel in a particular fashion. It also eliminated the need for landing at high angles of attack and provided pneumatic compensation in the event of losing an engine.
The article is called That Extra Little Lift by Tim Wright and published in May 2007 by the Smithsonian Magazine. Figure that should be enough to find it, and it would take more time than I presently have to properly cite it. Figure it would be a great read if you ever intend to return to this project, perhaps with you air powered engine :D
If I am not mistaken, for greater effect from the wing channel, it was necessary to install the screws in the place of the greatest thickness of the profile
YES i wanted to see that since you made that channel wind video
Tom, leading edge prop.
To get the highest slipstream and greatest narrowing you need the nacelles in front of the prop and the prop at the leading edge
Excellent working on this project
Hey man, if you want a strong structure with a light 3D printed frame, print out your piece then coat it in truck bed liner, its a little more heavy but each layer adds much needed structural integrity! 👍😁
"I've sold so many drugs I've learned how to measure grams without a scale" - drug dealer
Since the props are in the back of the channel, you would get a lot of airflow coming in that wouldn't flow over the channel unless the plane is flying forward which negates the point of the channels. What about if you put the props at the leading edge of the channel and the kinetic energy of the air coming off the props would force it over the channel?
at 2:47. Karen and Becky judging hard 😂
If thrust off a wing has any similarities with buoyancy (this I don’t know as I’m a boat guy) then the lift acts at 90 degrees to the surface of the airfoil. If this is the case than only the very bottom of the channel is producing true lift and all other points of the channel produce lift at a tangent to straight up, with the sides of the channel producing an opposite lift force to each other but none of it being a lifting component. This would explain why the lift generated has to be so high, as the contributing lift by the channel decreases as you move around the radius from the bottom.
It is nice to know that I am not the only one who prefers to work while sitting on the floor.
The low performance is due to the position of the prop. It should optimally be at the crown of the wing cord and sweep within a millimater of the surface for maximum low pressure. If you want to have a truly impressive performance you make a second wing hoop to sit over the prop turning the prop into a thrust nacell for high speed flight. When this upper surface slides back beyond the prop and angles down that surface becomes a vectored thrust surface producing additional lift. So with this upper surface retracted aft you get the lift from the Custer wing plus the vectored lift from that surface giving you high lift low speed high drag. Moving the upper surface forward transitions the combination to high thrust high speed low lift low drag. The problem with the Custer wing was always that the feature that gave it high lift limited its speed performance as with all STOL configurations. This simple transition configuration solves that problem to give a VSTOL capability which transitions to a high speed configuration which should give you 200kph performance.
I have been thinking a lot about the channel wing concept lately. I would like to try a similar test but adding a down turned duct or set of variable vanes after the prop to direct the propwash downward as well. This would increase the lift without increasing the forward thrust. If they were efficient enough you could theoretically hover. I think in this test you may not have been able to see much effect of the channel wing on landing as you had to increase throttle to gain the extra lift which also increased your airspeed. If you could direct the propwash downward you could increase throttle without increasing airspeed which would allow for slower flight. Nonetheless this was great to watch as well as your previous video test of the channel wing on the test bench.
Mirco ducts? Like a bunch of smaller ones.
The pitch up on power looked a lot like the lift is tied to the throttle. I think if tom raises the angle of attack of the wing section itself independently of the channels it would allow some more conclusive results as the whole craft would fly slower and the throttle would act more like flaps. Conversely you could add symmetrical sections at the outer tips and angle the thrust line down slightly. Real planes with blown wings rely on throttle control during landing but have shorter wings than similarly sized aircraft.
You have to explore the relationship between the airfoil profile which you chose and drag, but that’s not easy.
Great video as always!
Keep up the good work :)
Pretty interesting project, Tom! Nicely done! 😃
Stay safe there! 🖖😊
Perhaps reversing the counter rotation to inboard, instead of outboard will help with control, and torque.
Excellent working on this video
I think you should move the prop around like in front of the channel or in the middle of it . It might make a difference.
I imagined this myself many years ago. My idea evolved into a wing that contains numerous ducted fans built into the wings. It may need to scale up to a life sized plane to fit the fans into the wing thickness.
this man is gonna make a car in the future with a syringe based engine that repeats so it keeps going. i bet you
i have been waiting to see this plane be made after the channel wing video
This is really nice. Keep up your good job !
I wonder, would it be possible to use channel wings to steer a quad-copter drone? What I'm thinking is, take a drone with auto-hover capabilities, then fit a channel-wing above each propellor on a rotating mount. Then, if you want to, say, go left, rotate the channel wings so that they are all on the right side of their respective propellor, producing lift pushing the drone left.
Obviously, it would be much more complex, and probably less effective, than just varying the throttles on the motors to pitch/roll the drone, but I think it would be an interesting experiment.
Verynice design truly inspiring we need more of these full scale like to see this combined to the u 2 spy plane with dual scam jets or vector plates behind the prop
Thanks Tom....Ky over and out...!
if testing lift use more mass, it will accentuate the landing distances and dampen the maneuvers for easier testing
Try to move the prop to front of the wing, making the airflow in channels stronger. May be it will lead to significant difference.
Prop at the front doesn't work. Too much turbulence in the channel making the airflow weaker.
@@simonleonard5431 May be impellers at front will work. It has a straightening apparatus and less turbulence. Like jets on An - 72 airplane.
I would love to see a tilt wing, vertical takeoff plane. Also would love to see a tail-sitter that didn't need to tilt the wing, but could be essentially the same design.
Increase lift and reduce drag by moving the camber to midwing and decrease drag and increase lift more by dimpling the wing surface in the channel like a Golf Ball surface.
Great video! Always learn a ton.
i watch all the ads to support you. and also don't fastforward the included promotions.
that could change if you use funnels instead. and by using funnels the location of the propeller is important. a funnel will increase propeller back pressure at least in theory
Any way you could have one channel, in the middle of the wing? Or a biplane with central channels above and below the fuselage?
From that first vid I was waiting for this video, and it came out.....yay
I think the motor should be in front of the curved wing and slightly larger propellers than the Curve of the Wings and don't forget you need a few degrees of down thrust to keep the plane from popping up in the nose