Is anyone using Canards?

[iamchappy]

Is anyone using Canards? I am considering making some.

Please post your pictures.

[cstreit]

Canards? You mean dive planes?

[iamchappy]

Canards(usually used in aeronautical terms), dive planes(usually uses in nautical terms), same thing. Just wonder how well they work. 914's get pretty light up front over 100 when using a gt valance. Just wondering if anyone uses them other than F1 cars like the Spyder and such.

[barney911rs]

Like Chris, not sure what you are actually asking about. You talking about an actual wing, or just the on the small attachments on the front corners of the car. In car/racing circles those are known as dive planes. Here is a sample from the Penske RS Spider.



If this is what you are talking about, then yes they are used all the time.

[Mahler9th]

Yes. I have made at least 6 different shapes for my car-- all out of carbon fiber. My car has the popular 993 Getty body work. The picture below shows my running two sets at Sears Point last fall. Sorry for the quality-- maybe I have some more pics at home and can post them later.

The big dive planes made a difference... the little ones by themselves not so much. to get more front grip, I am next going to try moving my rear wing forward in 3 inch increments.

My process for making the canards is straightforward, starting with a fiberglass mold. Once i have a mold for a particular design, I use carbon fiber to make the parts. For these parts, I always use a vacuum bagging approach.

- Mike

[iamchappy]

I was planning on making them out of sheet aluminum and using angle aluminum for the mounting as it is easily shaped. I have been playing around with some cardboard shapes but the photos really help to see the angles there set at.

[TimT]

This is how we did it

[pgeorgeson]

More pics:

[Jack Olsen]

I made a set of these, initially thinking they functioned like little wings to generate downforce at the front of the car. The part I didn't understand was why they were usually set at such steep angles of attack -- it seemed like they'd have to be well beyond the point where a wing would basically stall.

Here are mine are in a photograph taken at speed:



As it was explained to me, winglets/canards/diveplanes aren't functioning as wings at all. They're vortex generators, and functionally they have less in common with wings than they do with the fans above open grocery store freezers. They generate swirling air along the sides of the car, most importantly down along the space between the track surface and the rocker panels. Their function is to stop air from getting under the car along its sides. This basically means (at least as far as my non-engineer's brain can get around it) that low-pressure air under the car doesn't suck air in from below the doors.

Here's a useful illustration from the Suzuka Racing site:



And here's a more succinct explanation from a Pelicanite in a previous thread:

Originally posted by BertBeagle
These are/were used on ground effects cars (ie the IMSA GTP cars of the 80's). What they accomplish is creating a vortex down the side of the car, filling the low pressure area that exists along the sides of the car, and that kept the air entering the underside of the car from the nose under the car and effectively increased the down force with a low drag penalty. Aero guys are always looking for something for nothing (ie downforce for no drag penalty) and this was a good find.

My guess would be that they improve downforce/grip at both the front and rear of the car, since they're essentially a component of underbody air management. But like other guys in this thread, I felt the effect as a better planted nose when I added mine.

Now a digression:

Once you get outside the sensible world of engineers, and into my own too-much-time-on-my-hands reality, you can use ride-height sensors and test any crazy aero idea you can put together. In the quest for more front downforce, I tried putting a wing up front:



Now, it took me a number of hours to build that thing, and honestly the time would have been better spent thinking about the principles involved -- that an automotive wing works because it creates a high-pressure zone above it and a low-pressure zone below it. If that's the case, then you should make sure that you're not creating your low-pressure zone right above the car itself -- so the same low pressure zone that's pulling the wing down will be pulling the car up.

Sure enough, in testing, the wing did what a wing does, without generating any significant improvement in downforce. At triple-digit speeds, it caused my fiberglass hood to flex and flap like crazy in the low-pressure zone it created. It actually pulled an unsecured section of the rubber seal up and out from underneath the hood.

[cstreit]

I made my own as well just trying to shed some understeer and it did make a definite difference.

I have since modified them based on some studies to reduce the sever angle at the rear of them.

[iamchappy]

Either i've already had to many Surley Benders tonight or thats one shaky photo, and Jack that front wing is totally crazy thinking, you must have been enjoying a few Benders when coming up with that one. You must of been thinking dragster.....

I have in my mind Chaparral. It seems thats when i first saw them being used.

[Jack Olsen]

Originally Posted by iamchappy

...Jack that front wing is totally crazy thinking, you must have been enjoying a few Benders when coming up with that one. You must of been thinking dragster...

Sometimes a hail-mary pass made from a point of total idiocy inadvertently leads you to a clever solution that you never would have thought of if you'd stuck to what was sensible.

In this case, though, that didn't happen at all.

Put another way: in 40+ years of 911 development, very smart guys have tired out just about every good idea there is. So sometimes not-so-smart guys like me shake out a bad idea or two.

I was surprised to see that I wasn't the first not-so-smart guy to think of it.

[tdz]

Jack's earlier description explains it best. The dive planes are to create a low pressure on the side of the car. They will only create a small amount of down force by themselves.

For front end down force, make the splitter as large as possible. The high pressure on the front bumper transfers onto the splitter pushing down. Splitters like the one on the RS Spyder have a raised center section to create a curved surface under the car to create a lower pressure.

Moving your rear wing forward will make it less effective in the same way that Jack's forward wing was ineffective. The low pressure will start acting on the deck lid. Likewise, the whale tail and the wing are fighting each other. A clean deck lid is better if you have a wing.

Aero Engineer

[Mahler9th]

One of my friends has the same bodywork as my car and ran a 3.8 wing element up front for about a season. Helped but wasn't enough. So he took it off and instead moved his rear wing 6 inches forward. That did the trick.

I will probably try a similar approach.,\