Channel Wing Plane 

I bet channel wing aircraft are hilarious when they fly upside down

The disgust look when he said "duck tape" is absolutely British. +1 would laugh again.

My wife says: "If it can't be fixed with duct tape, there is something wrong with it." LOL

I was waiting for this video with such excitement!!!!! Thank you for making it!!!

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.

I was literally just about to make one of these

I have done lots of research into the barrel wing. Amazing stability at low air speeds. Need counter rotating props for low speed control.

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.

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!

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'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!

Any difference in lift by having the motors push air over the wings, vs pulling air?

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.

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

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.

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.

Very interesting. I had never heard of that type of wing.

I always enjoy watching your videos, good to see you again!

Very impressive slow motion shots. They get better and better.

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 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.

YES i wanted to see that since you made that channel wind video

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.

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.

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.

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.

I would suggest using an impeller because it can pull air over the wing and then for forward thrust, you could use a propeller.

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.

Excellent working on this project

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.

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 wanna see that nearly vertical takeoff build!!

Wish I had a 3d printer. And the ability to use one. I'm so technologically illiterate! This is such an Awesome design

I knew Mr Custer. He lived in my home town. The channel wing plane was very cool. He was a brilliant man.

I anticipate your videos more than all those I follow!

Impressive built and design Thanks for sharing 👍😀

This guy out here playing ksp in real life. A genius!

Great video as always! Keep up the good work :)

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.

This is really nice. Keep up your good job !

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.

Always great Tom! Love your content

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.

Pretty interesting project, Tom! Nicely done! 😃 Stay safe there! 🖖😊

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.

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

Your channel is brilliant!

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!

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!

My Dad designed a channel wing aircraft in the 80's and did some work with the Custer company.

Excellent working on this video

Would you be interested in exploring magnus-effect cylinder-wing aircraft? In particular, I've wondered if such a cylinder could also be the thrust vector for a jet (or duct for a fan) the blades of which might simply be attached to the inside of the cylinder itself, and then angled with servos as desired.

Great video! Always learn a ton.

You always get the best ideas

I’m gonna go make one of these! really spiked my interest👍

Is the centre of thrust too low causing the pitch up, preventing the effect from really working?

Nice! I made one of those a few years back! I feel so smart having made one before Tom :-) I didnt test thrust and stuff, and it flew very badly though

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.

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.

That flew really well tbh

Love your videos mate!

Something that would fit nicely with your "using unusual forms of lift" theme would be the Magnus effect

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.

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.

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

bro we really need to get u to 1 mil subs u deserve it bro !! keep it up

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

Man it makes Netflix's data look like there are 56 million people watching Canadian Netflix

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.)

From that first vid I was waiting for this video, and it came out.....yay

Awesome! Didn't even know of a channel wing.

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.

i have been waiting to see this plane be made after the channel wing video

Fascinating. Thank You.

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.

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

perhaps covering the top of the channel with a partial channel or a fully ducted fan would reduce the pitching up by evening drag and lift above and below the wing

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! 👍😁

You can tell these recent videos were filmed during the lock down XD. Immaculate garden, people at home.

Perhaps reversing the counter rotation to inboard, instead of outboard will help with control, and torque.

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.

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.

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

Thanks for not dragging this over 10 minutes..

I suppose that the plane turned on the ground due to the rotor moment generated by the plane's engines this is usually corrected with the ruder in real planes but for an rca it must be changing the speed of one of the motors or the angle of one of the motors or putting motors against rotaries

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

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.

I think the real winner here for us viewers is that expanding foam filament. Very interesting.

Wow I never knew about this awesome video thanks

I would think that the low pressure zone ahead of a propeller has less energy than the high pressure zone behind them. I guess the original theory focuses on rearward props, but would it be more effective with tractor props, accelerating the air over the channels? Though additionally, a semicircular wing would be producing lift in various vectors going inward of the surface vs perfectly up, and that itself would suck away efficiency. Gosh there are a lot of variables to this!

You have to PUSH the air over the wing! Do it again propellers forward of channel wings, you will get more lift, and be able to do you slow speed flights.

Interesting Build, I must say I have never seen anything like it.

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.

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

Perhaps with a lot more drag the aircraft could get behind the power curve and allow for higher power settings at a slower airspeed and take advantage in the potential lift.

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

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.

you my friend has just got a new subscriber

By leaving the spar exposed the drag is increased by about 9 times more than if it was covered by an airfoil.