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I have been pondering something for a while and thought I'd throw it out to the community to see if anyone out there actually had an answer one way or another.

The question is this: Do the wings on 1/10 RC buggies actually do what they are supposed to do, namely generate a noticeable quantity of downforce?

This question needs a bit of qualification as some wings – see those on buggies like the Boomerang, Hotshot, Hornet and the like – are clearly just there for aesthetic reasons, as there is no way that their shape and size could possible generate anything useful in the way of downforce.

I was looking at the cars featured in the report on the Romsey '87 Worlds which @a.w.k. posted recently and it is possible that the big, gated bucket wings on some of the competitors might have had some effect, especially since they would have been fitted to cars much quicker, lighter and better balanced than your average Tamiya backyard basher. But then again, 1/10 buggies will generally have the drag coefficient of a grand piano and operate on rough surfaces that make aerodynamics very much a secondary requirement after mechanical grip, so will anything added to them make any difference?

I have seen special bodies for US oval racers which feature slippery sports car-type shapes, kick-up rear wings and big transparent Lexan air dams on either side to harness the air flow over the car and almost force it to generate downforce. Given the smooth surfaces these cars race on and the high speeds they attain, this seems viable, if aesthetically ugly.

But I have my suspicions that 1/10 buggy wings are purely there for show. Removing them would certainly change the car's handling, but this would happen if you removed any sizeable object mounted that far above the car's centre of gravity. On the Worlds cars in the article mentioned earlier, it could be that they served no function except acting as banners for sponsors, much like the airboxes on F1 cars, which are there purely because they are the most obvious surfaces on the car and therefore provide the most valuable advertising real estate. The wire wing mounts on most of those cars would also flex so much under load and vibration that they would surely render the attached wing almost useless.

Has anyone ever tested a 1/10 buggy in a wind tunnel? Does anyone here know or have a good idea if the wings have any real effect?

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The body and wings do make a difference. Modern buggies are cab forward designs which is for downforce. The wings have cut lines on them so you can cut them as big buckets or smaller depending on track surface. I cut mine in between big buckets and the smallest size. I haven't tested them on purpose but can say when I have ripped one the handling goes to ^%_#€@?. I have spares so I can replace them if I need to. They last ages though.

I have also experienced this with F1. When I started the wing was sitting lower and also at less of an angle. I got advice to change it so did and got more rear grip. One race the wing broke (that wasn't my fault, a missile like F1 car flew across the top of mine and took out a mount) and a floppy wing meant handling was noticably worse.

Touring car bodies are also designed with particular handling characteristics in mind and some are certainly easier to drive than others. Their wings also have cut lines so you can give more or less downforce.

I need to cut a new one for this Sunday, I'll cut it like a bucket to start and trim it throughout the day and see. The only problem with saying this isthe last 3 10th offroad meets have been rained off so i'm not holding my breath for this one to be on 

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I have noticed a remarkable difference in stability without a rear mounted spoiler, Especially with VLB!:rolleyes:

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I'd say it's like adding several grams of weight.  

That doesn't sound like much.  But adding 10 grams to the nose can change the characteristic of driving. 

Wind resistance is square of speed, I think.  The wind resistance at 20 mph, is 16 times from 5 mph.  Most entry level buggies can do about 15-18 mph with a silver can.  F-1 is faster. 

Beyond 20-30 mph, wind resistance has to be factored in.  For example, bicycles can go about 30 mph.  But if there is no wind resistance they can go 55 mph with same effort.  

Or, remove wind resistance of your legs, you might go faster than pedaling.  (see from 15 second mark) 

 

I think trucks can save a lot of fuel a year, if the tail of the container was covered by something less vertical.  Something a bit more round than this.  (The maker of this tail claims 500 million gallons of fuel savings a year, if all Canadian trucks are equipped with this)

ARrovbE.jpg

 

Rear end is almost as important as the front.  See how Porsche 962 tapered the tail end for smooth air extraction.  

24uKHvq.jpg

qep7m0g.jpg

I cannot unsee the determined look of the diff-cover...

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32 minutes ago, Juggular said:

Rear end is almost as important as the front.  See how Porsche 962 tapered the tail end for smooth air extraction.   

24uKHvq.jpg

 

That isn't for smooth air extraction. The underside of the 962 is shaped like that to form a venturi chamber, which is a form of ground effect. The way the chamber is shaped means that when the car moves forward at speed air is drawn from the smaller area further forward to the larger area further back. This creates an area of lower pressure under the car, which effectively sucks it to the road. Although ground effect was banned from F1 in the early 1980s it was still allowed on sports cars until much later.

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47 minutes ago, Juggular said:

I think trucks can save a lot of fuel a year, if the tail of the container was covered by something less vertical.  Something a bit more round than this.  (The maker of this tail claims 500 million gallons of fuel savings a year, if all Canadian trucks are equipped with this)

ARrovbE.jpg

This is another example of air pressure differential and drag. When the truck moves forward at speed, the squared off end of the container moving through the air creates a low-pressure hole, which causes the surrounding air to be sucked in to fill it. This creates areas of increased turbulence behind the container and a lot of drag, even more than you would expect a huge square box travelling at 70mph to suffer. The shield creates a stable pocket of low-pressure air at the end of the container and diverts the air displaced by the container around it, reducing drag, increasing fuel efficiency and probably reducing turbulence for other motorists, too.

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51 minutes ago, Juggular said:

I'd say it's like adding several grams of weight.  

That doesn't sound like much.  But adding 10 grams to the nose can change the characteristic of driving. 

Wind resistance is square of speed, I think.  The wind resistance at 20 mph, is 16 times from 5 mph.  Most entry level buggies can do about 15-18 mph with a silver can.  F-1 is faster. 

Beyond 20-30 mph, wind resistance has to be factored in.  For example, bicycles can go about 30 mph.  But if there is no wind resistance they can go 55 mph with same effort.  

Or, remove wind resistance of your legs, you might go faster than pedaling.  (see from 15 second mark)  

There is a difference between downforce (inverse lift created by an aerodynamic device and exerted on a body such as a car) and drag (which is the wind resistance you talk about above, more or less). While I have no doubt at all that all RC car wings create drag, I am not so sure they create any effective downforce. For a start they are not really proper aerodynamic devices. While wings in F1 and other motorsports are inverted aerofoils, or aerodynamic devices shaped like aircraft wings to create and exploit differences in air pressure to enhance traction, RC wings are basically bent pieces of plastic. If they do create downforce, it is due to simple Newtonian physics rather than aerodynamic subtlety. If a flat piece of plastic is placed at an angle of, say, 45 degress from horizontal and then moved through the air at that angle, it will push the air out of the way by deflecting it upwards, while the air in turn will try to push the plastic downwards. If you attach that plastic to an RC car, hey presto, you have an RC wing.

The trouble is that this is a hugely inefficient way of creating downforce, but a very efficient way of creating drag. This process moves a lot of air and creates exactly the sort of turbulent air behind it that the truck shield above is trying to prevent and generates minimal downforce in the process. Although the big bucket wings with large end fences I mentioned earlier might create some downforce in this fashion (as well as contributing to straightline stability) most 1/10 buggy wings simpy wouldn't, as they are too flexible, too small, too crude or too badly affected by other aerodynamic compromises to make any difference, while the cars are either too slow or too heavy to notice.

That is not to say they have no effect. I once removed the rear wing and mount from my Mid in order to see if it made any difference. It did, but more I think because the Mid mount was a chunky piece of plastic in its own right and was mounted above the centre of gravity, so affected the handling quite markedly when removed. I also think that straightline stability was affected, because although an RC wing will make the air behind it unstable, if it has big enough end fences it will guide air over it quite effectively up until it flows over the trailing edge and merges with the air on the other side, by which point it no longer matters. I also think that there is a big psychological effect of having a wing there, as it looks effective and once our brain gets used to seeing a wing there it gets rather unsettled if it is missing. Finally, @Juggular is right that 10 grams in the right place can make a difference. The problem is that a 1/10 off roader might handle better if you took the wing and mount off and added the equivalent weight plus 10 grams somewhere down low on the chassis.

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2 hours ago, Jonathon Gillham said:

The body and wings do make a difference. Modern buggies are cab forward designs which is for downforce. The wings have cut lines on them so you can cut them as big buckets or smaller depending on track surface. I cut mine in between big buckets and the smallest size. I haven't tested them on purpose but can say when I have ripped one the handling goes to ^%_#€@?. I have spares so I can replace them if I need to. They last ages though.

I have also experienced this with F1. When I started the wing was sitting lower and also at less of an angle. I got advice to change it so did and got more rear grip. One race the wing broke (that wasn't my fault, a missile like F1 car flew across the top of mine and took out a mount) and a floppy wing meant handling was noticably worse.

Touring car bodies are also designed with particular handling characteristics in mind and some are certainly easier to drive than others. Their wings also have cut lines so you can give more or less downforce.

I need to cut a new one for this Sunday, I'll cut it like a bucket to start and trim it throughout the day and see. The only problem with saying this isthe last 3 10th offroad meets have been rained off so i'm not holding my breath for this one to be on 

I accept that aerodynamics will be a much bigger deal for circuit cars, especially F1 cars, which are presumably scale models and therefore have proper wings on them (although I fear that aerodynamic efficiency decreases along with the scale of the model). Road circuits are also more stable environments than off-road circuits, so you can rely on a flat circuit and a car adapted to use it when factoring in downforce. The aero doesn't scale completely as the materials react differently at smaller scales and thicknesses (it would be very difficult to replicate Red Bull's flexible 'tea tray' splitter in 1/10, for example, or the sliding ground effect skirts of a Lotus 79) and the car will react more to road blemishes, small stones and dirt, but the wings will still work and changing the angle of attack will presumably make a noticeable difference.

The wings are less of an issue for touring cars, but they are IRL too. With touring cars it is more about getting it as low to the ground and creating as stable a pocket of low pressure under the car as you can. This obviously doesn't work for RCs as they are hollow underneath and leak air through the wheelarches, but if you can get the nose of the body down on the deck and keep it there you can possibly create a stable enough low pressure area behind it that it might make a difference. Also, the Newtonian effect mentioned above works over the whole of the front cross section of the body in a touring car, so just driving it will create a small amount of downforce.

I'm not sure what buggy manufacturers have been claiming with regard to cab-forward designs, but it sounds unlikely. When you consider that the cab on a cab-forward shell sits immediately behind a huge, flat shock tower mounted at right angles to the airflow and a pair of equally huge shock absorbers, plus an even bigger set of wheels covered in spikes, it isn't going to matter where you put the cab or what shape it is, as it isn't going to make any difference.

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5 hours ago, Yalson said:

That isn't for smooth air extraction. The underside of the 962 is shaped like that to form a venturi chamber, which is a form of ground effect

 

So it is!  I was just watching a youtube thing on the carburetor in Supermarine Spitfire.  It is a venturi effect. 

My Gravel Hound's body hangs down a bit on the sides.  I was going to trim it, but I figured, "eh, maybe it'd be like F1 side skirts."  Yes, you can laugh.  Going off-road with a silver can nonetheless, and 5mm down on the sides, will not do anything.  An "exhaust fan" sucking out air from under would be pointless too.  

I think the bodies do create some downforce.  It is true that the nuances of aerofoils between NACA 0012 and a plywood is probably lost in RC cars.  Would it matter, though?  We all have stuck our hand out of the car window, and air-surfed with our palm.  30mph is quite fast.  The difference between Konghead body, and Porsche 956 body would be quite substantial (in air resistance and drag).  Konghead will have little to no downforce.  But Porsche 962 would have more then a few grams of downforce at 30 mph, if somehow the body could be held horizontal and downforce could be measured.  As you say, it's more due to Newtonian physics, but I have a feeling the RC car wouldn't care.  ;)  

Cab-forward design might not have much effect either.  If they are going to do it, they can do it a bit more logically.  The way it is, it looks like they were aiming for it to pitch up.  Having a tower cover would be better. Up to 2/3 of the way.  Some of the cab-forward design looks like an airfoil to me.  To counter the lift, it seems like they added turbulance makers.  I think it would be easier to just slope the windshield or water drop shaped cockpit like Porsche 962.  They may have added an air-brake not to add braking effect, but to give structural integrity to side wings.  But I'd cut that away.  All this may not matter much, but if I'm racing, I probably don't want the air brake effect even if all it's only doing 20mph.  

 

tAdxHtZ.jpg

 

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When I got back into touring racing around a decade ago, I started with a TA05-IFS running the Ebbro 350R body.  I was a slippery-shape GT body with a moulded ABS plastic rear wing (not a formed lexan bucket).  At the time, everybody was running the Protoform Mazda 6 body, and they all told me I'd need to get the same if I wanted to be competitive.

I was utterly sure they were talking nonsense, and I even picked up both bodies and ran around the room with them to prove a point.  Yes, utterly unscientific and done more for comedy value than to prove anything, but there you go :D

Anyway, during one race the rear wing snagged on a barrier and was ripped off.  For the rest of the race, the car was very hard to drive - unstable in a straight line and hard to turn in.

Before the next race I used some rigid battery tape to form a makeshift flap with end fences on the back of the body.  Straight-line stability was improved.  The following week I raced a new Protoform Mazda 6 like everybody else, with the big bucket wing on the rear, and it was like driving a different car.  So, bizarre though it sounds, it does have some effect.

I'm certainly no expert in aerodynamics, but I wonder if big rear wings are actually more about drag than downforce.  Like the flights of an arrow, which stop the back end from overtaking the front by creating drag.  Medieval fletchers didn't know about aerodynamics or even Newtonian physics but they knew how to make an arrow fly true.  An RC car needs to drive straight and true but also to keep its wheels on the ground - hence the bucket being angled.  The drag may slow the car down a little but the trade-off is stability.

I wonder if you could create an effective aerofoil that would produce downforce without producing so much drag, like a 1:1 car?  In theory the physics is the same, except the car is 10 times smaller but the air molecules remain the same size.  Does that impact how you would design a wing and a body?  RC cars generally go faster and high a much higher power-to-weight ratio than full-size race cars, but their CoG is different too.  If you could go all-out and build a complete body, undertray and aero package from exotic materials, how would you design it?  I'm genuinely interested to see what a professional body designer with experience in F1 or GT would come up with.

 

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What Mad Ax said, I drive my Xray T1fk05 with the 408R Vemac body from the ta05 ifs and with a dodge stratus protoform body. Handling is better with the protoform body, less spinning out, changing directions feels much smoother. 

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3 hours ago, Mad Ax said:

When I got back into touring racing around a decade ago, I started with a TA05-IFS running the Ebbro 350R body.  I was a slippery-shape GT body with a moulded ABS plastic rear wing (not a formed lexan bucket).  At the time, everybody was running the Protoform Mazda 6 body, and they all told me I'd need to get the same if I wanted to be competitive.

I was utterly sure they were talking nonsense, and I even picked up both bodies and ran around the room with them to prove a point.  Yes, utterly unscientific and done more for comedy value than to prove anything, but there you go :D

Anyway, during one race the rear wing snagged on a barrier and was ripped off.  For the rest of the race, the car was very hard to drive - unstable in a straight line and hard to turn in.

Before the next race I used some rigid battery tape to form a makeshift flap with end fences on the back of the body.  Straight-line stability was improved.  The following week I raced a new Protoform Mazda 6 like everybody else, with the big bucket wing on the rear, and it was like driving a different car.  So, bizarre though it sounds, it does have some effect.

I'm certainly no expert in aerodynamics, but I wonder if big rear wings are actually more about drag than downforce.  Like the flights of an arrow, which stop the back end from overtaking the front by creating drag.  Medieval fletchers didn't know about aerodynamics or even Newtonian physics but they knew how to make an arrow fly true.  An RC car needs to drive straight and true but also to keep its wheels on the ground - hence the bucket being angled.  The drag may slow the car down a little but the trade-off is stability.

I wonder if you could create an effective aerofoil that would produce downforce without producing so much drag, like a 1:1 car?  In theory the physics is the same, except the car is 10 times smaller but the air molecules remain the same size.  Does that impact how you would design a wing and a body?  RC cars generally go faster and high a much higher power-to-weight ratio than full-size race cars, but their CoG is different too.  If you could go all-out and build a complete body, undertray and aero package from exotic materials, how would you design it?  I'm genuinely interested to see what a professional body designer with experience in F1 or GT would come up with.

 

I wondered this too. As I said before, on-road and off-road have different issues with regards to aero. It is much easier to see a tangible effect with on-road cars as the conditions are much more stable and therefore you can change details and replicate similar conditions to test them in. If you swap the body on a touring car to see if it changes the handling, as long as it hasn't rained you can be sure that the circuit will be similar in terms of grip and texture. You can't necessarily do this with off-road as the number of variables is so big. On-road cars also generally have enclosed bodywork, which makes it easier to create shapes which create genuine aerodynamic effects.

The scale question is a real issue and a potentially confusing one. Buggies are generally 1/10 scale, meaning that you could consider their 'scale speed' to be 10 times their actual speed. So a 1/10 buggy doing 10mph is in scale terms doing 100mph. This is an imperfect translation, however, as 1/10 cars can in certain conditions attain real speeds of 30, 40 or even 50 mph, which would mean a scale speed of 500mph. Aerodynamics do not scale, though. They always only act at 1:1 scale, so will act upon the car's actual speed, not it's scale speed.

A good example of this would be F1 cars. The famous (and probably accurate) legend is that once an F1 car reaches around 100mph, it is creating more downforce than its own weight, so if it weighs 500kg, it will be creating 500kg or more in downforce. The supposed result of this is that at 100mph you would be able to drive the car completely inverted, for example across a ceiling if you could find one big and flat enough. The specifics of this may change over time, as the weight of the cars changes with the rules (the current minimum weight for F1 cars is 734kg), meaning that unless downforce keeps pace with or exceeds minimum weight increases, the speed at which you can drive the car upside-down may go up. But this would still be possible for every car on the grid at some speed, at least in theory.

This effect does not scale down, though, for reasons which I do not have time now to go into fully (but which someone else hopefully might do).

Even if a 1/10 F1 car was an exact replica of its full-sized cousin (which they never are) and it's aero components were as effective in scale terms as their full-sized equivalents (which they usually aren't) then you would still not be able to drive a 1/10 F1 car across the ceiling at 10mph. The aero effects would still require the car to generate enough downforce to cancel out its weight.

I will have to come back to this later. I have stuff to do, I'm afraid.

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I really should tighten up my scale notation, too. I think it should be 1:10, rather than 1/10.

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2 hours ago, Yalson said:

...as long as it hasn't rained you can be sure that the circuit will be similar in terms of grip and texture. You can't necessarily do this with off-road as the number of variables is so big...

My skill at off-road racing is limited to crashing into barriers and not noticing when a kingpin has fallen out of a steering hub in the last qualifier, so I enter the final race with a car that wanders across the track and ultimately spits a driveshaft, so I'm not really qualified to comment on the above.  But, that said, there are some very good buggy racers out there (world champs and the like) who can drive a car and tell what it needs to make it work on a given track.  And not just minor adjustments like "a bit more front camber here" or "another turn of preload there" - the Manta Ray went through a period of evolution on the world stage and ultimately became the world-beating Top Force in the hands of someone who understood how to take a design and improve it.  This despite the changeable conditions on track and the inherent inconsistency of off-road racing.

One of the things the Top Force was really noticeable for was its sloping body shape that carried on into the big rear wing - something I don't remember seeing on a Tamiya before.

(Note: my history of the era is a little hazy and I'm not entirely sure that the body evolved with the worlds car - it's possible the body and wing are totally unrelated to the work done on the race track)

My point is that a top-flight buggy racer should be able to try a variety of different wings and bodies and tell whether they're making a difference.

 

Those are some fascinating points you raise re: scale, thanks for sharing.  Are you into aerodynamics on a professional or academic level?  You seem to know your stuff :thumbsup: 

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Ha ha! Thanks. No, I have just followed F1 for a very long time and understanding aero has become a sort of accidental hobby. I would love to talk to a proper aerodynamicist who really knew what they were talking about. I have Adrian Newey's book on the pile when I get to read it, but I'd love to talk to the man himself.

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If you want to believe that your buggy wings are not helping you and as such run without them, then by all means why not! 

However, You’ve got not hope however of convincing me to give up the wings on my buggys. Or any of my rc cars for that matter. 

Of all the years I’ve driven and raced RC cars, the wing has always been a very important tuning tool. 

However I will agree that some Tamiya buggy wings are less functional than others in the handling improvement categories.

 

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Fair enough. I haven't driven a buggy for a long time, but I am building one now for my daughter and I wouldn't build it without a wing as I think it looks better that way.

As for proper racing buggies, I am still on the fence. I again would include one for aesthetic reasons, if nothing else, but I am still torn over their actual efficacy. Looking at it logically they are almost certainly functionally useless at generating downforce, but they may have other benefits which go beyond that brief.

I wouldn't suggest anyone do away with their wings simply on my say-so. I just wanted to know what other community members thought of them and whether anyone knew of any research into whether they actually do what maufacturers say they do, or had anecdotal evidence one way or the other.

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Wings on cars (1:10 but also 1:1) work like reversed aeroplane wings. The flow on both sides of the wing is different.

On an aeroplanewing the air travelling over the wing has to travel more distance compared to the air travelling under the wing because of the curve in the wing. As a result the aeroplane lifts. The more speed the more lift and the more wing the more lift. At a lower speed the wing slats are deployed to generate enough lift when landing. And at the moment of landing the lift dumpers come out (look at the wings the moment before touching the ground, The lift dumpers are the parts that seem to come loose). This is done to break the flow over the wing  to stop the lift.

On cars the effect is the same but reversed (as the wing is upside down), lift becomes downforce. So when speed increases the effect will be stronger (more downforce). So my guess is it works, even in 1:10, because of the low weight of the RC car and the speed it can reach.

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15 hours ago, Mad Ax said:

  Like the flights of an arrow, which stop the back end from overtaking the front by creating drag.   

Wow, that's brilliant.  That could explain the "Air Brake" part of the wing!  I stand corrected: Keep the air brake!  

Edit: Keep the air brake to increase tail stability, at the cost of speed.  

 

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5 hours ago, No Slack said:

Wings on cars (1:10 but also 1:1) work like reversed aeroplane wings. The flow on both sides of the wing is different.

On an aeroplanewing the air travelling over the wing has to travel more distance compared to the air travelling under the wing because of the curve in the wing. As a result the aeroplane lifts. The more speed the more lift and the more wing the more lift. At a lower speed the wing slats are deployed to generate enough lift when landing. And at the moment of landing the lift dumpers come out (look at the wings the moment before touching the ground, The lift dumpers are the parts that seem to come loose). This is done to break the flow over the wing  to stop the lift.

On cars the effect is the same but reversed (as the wing is upside down), lift becomes downforce. So when speed increases the effect will be stronger (more downforce). So my guess is it works, even in 1:10, because of the low weight of the RC car and the speed it can reach.

I understand the principle of downforce and how it is made. This works for wings on 1:1 cars, but not on 1:10 cars, as they are not shaped like aeroplane wings. The bucket wings on RC cars are not aerofoils. They would not create lift if you invert them, except extremely inefficiently by the crudest of Newtonian reactions that I detailed above.

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14 hours ago, Mad Ax said:

I'm certainly no expert in aerodynamics, but I wonder if big rear wings are actually more about drag than downforce.  Like the flights of an arrow, which stop the back end from overtaking the front by creating drag.  Medieval fletchers didn't know about aerodynamics or even Newtonian physics but they knew how to make an arrow fly true.  An RC car needs to drive straight and true but also to keep its wheels on the ground - hence the bucket being angled.  The drag may slow the car down a little but the trade-off is stability.

I wonder if you could create an effective aerofoil that would produce downforce without producing so much drag, like a 1:1 car?  In theory the physics is the same, except the car is 10 times smaller but the air molecules remain the same size.  Does that impact how you would design a wing and a body?  RC cars generally go faster and high a much higher power-to-weight ratio than full-size race cars, but their CoG is different too.  If you could go all-out and build a complete body, undertray and aero package from exotic materials, how would you design it?  I'm genuinely interested to see what a professional body designer with experience in F1 or GT would come up with.

 

The arrow flight analogy is certainly appealing with regard to the effect wings seem to have on 1:10 RC cars. I have also wondered about whether a true aerofoil on an RC car would be more effective. It can't be that hard and I am sure someone must have tried it, but the fact that we do not see every Kyosho, Yokomo, Associated, Schumacher and the like fitted with true wings suggests it doesn't work. You could make your own pretty easily:

1. Take a standard straight 'bucket' wing.

2. Turn it through 180 degrees so that the upward flick is now facing forwards.

3. Trim the upoward flick so that it is relatively shallow, but still with a pronounced upward curve. Keep the side fences as big as possible. You'll need them in a minute.

4. Fit a piece of flat lexan across the shallow bucket. Trim it and tape it down so that it encloses the bucket section completely, creating an aerofoil cross section.

5. Add additional stuck-on endplates to the side fences, to guide the airflow.

6. Put mounting holes in the curved section, so that the wing sits at a slight angle. The more pronounced the angle, the more downforce it should create. If you want more, you can experiment with small 'Gurney flaps' on the upper side of the trailing edge of the wing. Not sure how effective or what size they should be at this scale, but it might be worth a pop.

All wings create drag to some extent, as the difference in air pressure between the top and bottom has to be reconciled at some point, which creates turbulence and imperfect flow patterns. The more pronounced the angle of the wing to the airflow, the more drag it will create. Have a look at the difference in aero setups on IndyCars from the 80s and 90s between high speed ovals and road circuits for and example of how racing teams reconcile this with the need for speed.

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An interesting approach, but it would probably be simpler and lighter to use an inverted Jedelski wing. We know this works very well at model scales. 

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No Slack describes it correctly.  I use "wings" loosely, myself. 

If Yalson is describing "wings" as airfoils, he's right too, in that RC cars don't have airfoils.  

Airfoils are difficult to make with Lexan.  (Maybe F-1 cars with plastic wings could have actual airfoils?) 

eHQwenh.jpg

["Clark YH airfoil" below.  Such an airfoil is used upside down in real cars, as No Slack and Yalson mentioned.  Not often found in RC cars, because Lexan has uniform thickness]  

JeOFqgZ.jpg

Most RC wings work more like upside down flaps on airplane wings.  They use mostly "Newtonian physics," as Yalson said, rather than Bernoulli effect.  

RC wings being so small, simple Newtonian physics works just fine.  

I learned a few things: 

1)  Drag of the tail wing can work like the feathers of a badminton shuttle -- giving directional stability by creating drag at the tail.   

2)  Wings (either by Newtonian physics or having airfoils) does help even RC cars.  

UCZF22A.jpg

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