My Impressions of the Ventral Wing

[Bud Man]

@Steven Haines,

They are pay per view. I he accepts paypal. [smirk]

 

I can’t help, I don’t have anything but phone on my phone and most of the time that does not work well. [frown]

 

[GreggyC]

Hey Sixam, goood thinking, so here is my struggle with the hydofoil notion. When the ski is on edge the tip stays down or level when there is no vertical lift generated by the ventral as it is at about 90 degrees to the surface of the water. There is definetly an increase in drag when adding the inverted ventral, the ski is noticeably stickier, yet there is no narrowing bettween the surfaces...it's been 30+ years since my last fluid dynamics class, so I know I am at the finge of my skill sets here. Other odd thing, you would expect that tail lift would be a bad thing at the ball under load. The only way I can blow a tail is if I am really broken over the front of the ski at the ball. The tail is noticeablly firmer in the deep part of the turn.

 

Bud...Nano - Mid, I think a 65" have zero idea on flex.

 

Sorry Steve, no idea about how to view on the phone. I viewed on my iPad and Laptop.

 

Greg

[Steven_Haines]

I think you're right Bud! I can't wait to get back on the water! It has been way too long! BOS is my only form of sanity right now.ha ha

[JC McCavit]

After hearing Horton's initial impression, I am beginning to wonder if Goode Skis are the only ones that need all these extra gizmos.

[CsSkis]

In response to GregB...

 

All skis ride at some angle-of-attack relative to the surface of the water. The only times that I have had the tail of my ski "flat" relative to the surface of the water is when I'm just about to sink the tip and go out the front. (Even in a turn, the ski is at an angle-of-attack relative to it's motion through the water) Therefore, the ventral wing, if mounted parallel to the bottom of the ski (as indicated by everything I have read, so far), would always be providing some amount of lift. As we have all read Schnitz's "Your ski is a lever", the additional tail lift will tend to lower the tip. Again, I am not passing judgement on the effectivity of the ventral wing for some skiers. I just want people to recognize what it is, and isn't, doing.

 

I'm in the process of retiring after 35 years as an aerodynamicist at a major airplane manufacturer, Just for entertainment purposes, over the years, I have had many discussions with other skiers in my organization regarding the "fluid dynamics" of waterski design. It is a very complex set of problems - so, I really do like people (like Chet Raley) to come up with new concepts to experiment with.

[CsSkis]

Oh, I forgot, I have a GoPro video that was taken pointed backwards from the back boot and looking at the tail of the ski. The video was taken during a 35 off slalom pass that was being run by a National caliber skier. Throughout the entire pass, the tail of the ski is forming a (deep) trough in the water, which proves that the ski (at least for him) was always at some angle-of-attack during his slalom pass.

[GreggyC]

So, this morning I rode the ski and took the time to look back after my runs to see the water flow from the tail...there appears to be narrow strip of displacement deeper than the tail of the ski which would suggest there is some lift from the ventral. Without being able to see the ski under water under load it is hard to know how much water is being displaced.

 

Traditional wings are set to 6 - 8 degrees of angle and the ski has some pitch as a function of water speed, placement of the bindings and weight distribution on the ski. The wing has to be pulling the tail down which increases drag. Increased drag ='s increased load ='s a need for more acceleration and speed to get wide on the boat. If you can decrease drag and decrease load, and you can get wide on the boat with less effort and speed while the ski is in a more natural position to fully engage the rocker at the ball, that would be a good thing...right? That is the simplest comparison I can make.

 

The biggest downside to the vetral for me is when you roll left or right, the skis is going left or right. So you have to be careful not to roll on edge too early. The biggest upside is I now run a narrower less loaded gate, I get very wide at 1 with no excessive water speed making it easy to drop in to the rythym of the run. Since the angle comes earlier with less effort it is easier to just drop into a solid position and ride the connection out to the other side, this is a new experience for me.

 

Thus far I have seen setup on Strada's, RS1's, Elites and D3's...similar results.

[Bud Man]

Good post @GregB, I enjoy reading updates. Maybe @Horton can lend you his GoPro to post the video for all of BOS visitors to view. Sounds like everyone would be "winning." (John, Chet, Dave, BOS visitors)

[Steven_Haines]

Very cool! I want one! (or 2 or 3) d;-)

[Bud Man]

@OB, I would guess you added the ventral as shown in this picture that jdarwin posted. I thought you posted a couple of pictures, but I could not find them. Did you happen to take pictures of your setup? If not like this picture, then how? Thank you.

[Boody]

OB, that is awesome. Would also like a pic of the wing set up. Your running a regular wing and the ventral I assume?

 

Thanks

 

[Ed_Obermeier]

So after reading all of the above comments on this I'm left with this question - is this ventral wing setup going to help a less than perfect form skier improve their form, and thus performance (read - is it going to help fix problems), OR do you need to be basically very solid form wise to begin with to be able to take advantage of whatever it offers (read - will it punish a less than perfect skier)? Opinions?

[Wish]

Frustrated. The only pic that shows up is Bud Mans with the tape measure. The others are all tiny thumb nails on my computer and don't exist at all on the iPhone. Can anyone work that out. Would really like to see the setup on a fin.

[scoke]

GregB posting in this thread, wow the fecal matter just got real! Greg is the real deal and has thought through quite a bit of stuff already, done his homework and is an innovator.

 

Recently I watched approximately 8-10 skiers get ventral setups in some form or fashion added to their skis. They all varied in height, weight, ski makes, and buoy capabilities. Not all setups should be the same but the end product for every single one of them was the same "Wow my ski feels more stable/free/alive" etc. It was an amazing experience just to watch.

 

On that same note, a single ventral added as a minimum had a good result but some skiers who had different characteristics, needed a dihedral or other adjustments.

 

Then the 34mph vs 36mph impacts come into play. Parasitic drag vs efficient drag really starts to become an issue in the 34 v 36 discussion.

 

Also, after watching different strength to weight ratios, i am suspecting certain setups for certain types of skiers as well as a "standard" setup.

 

From an analysis standpoint, the vectoral equations are rather large. J3 and I starting discussing the differing options of variables. It would be quite a feat to model the fin + wing + ventrals with water flow then add in the fact that it's not straight line flow (non-laminar) but disrupted flow to the extreme end of the spectrum.

 

it's hilarious to ride in the boat for the same skiers set 1 then set 2 with ventral. funny stuff.

 

 

 

[MattP]

@Wish The reason you can not see the other ones is because the users did not embed them into the comment page but loaded them to the site. When you click the thumbnail it will download into your downloads folder on your computer where ever that may be. If I get the time I will go back and re post those if I get the chance

[Steven_Haines]

Where can a guy get one? I looked on Goode's website and didn't see it. I guess I call customer service?

 

[MattP]

Here are some photos that @OB set me to post of his Setup ( @OB one of the pictures you sent me did not come through right in the email)

 

 

 

 

[Chef23]

If I see that picture correctly it has a normal wing on it at your regular angle and the ventral wing on it set level.

[Marco]

To attach, is it just a matter of drilling a couple of holes in the fin? What about adjustment potential? Is the fin ruined after the holes are drilled if you decide not to use the ventral, or do the new holes not affect performance significantly?

[Bud Man]

@Marco,

I would guess that the two 1/8” holes would not affect anything at all, but you could easily fill them with a spot of epoxy like JB weld and sand smooth.

 

[Steven_Haines]

Ok, but what happens when you want to make a fin change? To do that you'd have to drill larger holes to allow the ventral to be adjustable. Would that create durability issues?

[GreggyC]

Shouldn't be an issue. The photo of my fin shows where I have multiple holes from moving the ventral around and it skis fine. Before we messed with the ventral, we were skiing without wings and carving the fins up in an attempt to reduce drag. There is a limit to what you can do and still have an effective fin, mine is probably pretty close to the limit.

 

What we know doesn't work is filling in the holes. Ski is fast and very difficult to control.

[MattP]

From what I now about fins which is not that much ( @horton should chime in on this he's the fin guy). The large holes that are in the fin allow the ski to relieve pressure that is on the fin. Each company has a different pattern for the most part. So if you were going to go drilling into your fin the take out the V wing then you might be changing how your ski reacts, or it may not have that much of an impact on the skis performance.

 

As for the V wing and what would happen if you change your fin settings I would drill the holes for the wing just like they are drilled for the stock wing with the ability to adjust the angle.

[GreggyC]

Makes sense to me.

[ForrestGump]

Holes at the upper front area of the fin have far less effect than holes at the trailing edge. If I recall, it's a 3:1 ratio of effect. So essentially, you could drill a 3/8 inch hole in the front upper edge with no effect on the ski. You go and drill a 3/8 hole in the rear trailing edge and you'll feel that.

[Ed_Johnson]

Shane is right. Just look at the HUGE Slot at the back of Schnitz's Slot Fin. Allows the ski to turn much better than the stock fin, also allowing you to run the fin deeper. The Speed Slot Fin significantly keeps the speed up through the preturn into the hookup on my MID over the stock fin. After what OB says, I can only imagine what the Ventral would add to it.

[Steven_Haines]

Ed,

Get on that V. Wing/Slot Fin combo and report back! (PLEASE!) Ha ha

[Steven_Haines]

I just got off the phone with Mary at Goode. She said the Ventral will be showing up on their website next week. They will be sold as a pair and will be priced between $50.00-$60.00. They aren't taking orders yet.

[Nick Sullivan]

http://goode.com/wsRALEYVENTRAL.html

 

Kind of expensive.

[Old MS Accout]

I should have got one when Chet had them for 40.00.

 

Thager, you have a new project.

[Wish]

Did I miss something on the Goode web page. There is no explanation as to how to install VW, measurements for installation, any instructions at all on why or why not all three. The cost is funny as well. $50 for one little one but $70 will get you a pair of large ones. Why would I need the pair? If you didn't know of BOS (who doesnt) you would just scratch your head in wonder. On this site alone there is enough detail to not only instal one but I'm thinkn I'll take a crack at making one. Same rig as OB has going. JH should get royalties for providing the means to instal. About the only thing I cant tell is the exact angle/degrees of the small (or large if different) of the wing. JH says "about 45 degrees". Any one have an exact degree. Anyone have exact size for the small wing?

[MattP]

yeah the Goode website in my opinion needs some help (ok a lot) and better descriptions of products. All of the TM next to every thing makes it annoying to read about the products.

@Wish you do not get 2 for $70 that is the "item" number in the list.

[Bud Man]

@Wish, I believe the large is 112°

[kstateskier]

let me get this straight... FIFTY DOLLARS for a little bitty wing? Hell ask HO or Radar for an extra wing and they'll mail you one free... Goode is selling this for $50? Why am I not surprised! Is it made of enough silver to kill a werewolf?

 

I've got 4 wings in my event bag, can't someone just post the measurements of where to mount this wing or does that come printed on a 3x5 card with my $50 wing?

[kstateskier]

Never mind I see now its not just the wing, its an entire fin... I don't remember exactly but I'm thinking Schnitz Slot Fin was close to $100, but that fin really turned the Monza into something you could ski on with some consistency.

[Nick Sullivan]

Where did you get the idea that it was a complete fin?

[kstateskier]

The goode site shows an entire fin... Maybe I'm wrong, it just appears that for $50 you get an entire fin.

 

http://goode.com/images/RaleyVentralFinoutlinesm.gif

[MattP]

All you get is the wing for either $50 or $70/ wing.

 

Under the photo posted above from the Goode website it reads.

 

"The above photo shows the Raley VentralTM placed in three different locations. The forward and lower Ventrals are Mini. The rear Ventral is a Large."

 

It is just showing the set up that Chet uses so that you could possibly need 3 of the wings and could spend $170 on wings.

[JC McCavit]

The better the design of the ski, the less wings required.

[Ed_Obermeier]

Deleted double posting - sorry.

[Bud Man]

My skiing knowledge pales in comparison to Chet Raley and Dave Goode, so my opinion should be taken with a grain of salt, but I can’t help but think that the way the vw works is simply adding drag 100% of the time. The ski manufacturers seem to have worked hard to make skis ski faster and faster, so why would we want to add drag all the time, IF that is what the vws do.

 

I have seen a maxi wing on Schnitz’s Website that I would think would not add drag 100% of the time and can be adjusted to add more or less when the ski is ridden at a tip down or up attitude.

 

I believe that the vws probably pull the tip down and help people ski better, but is that the best way to accomplish that? (IF it is just drag) A blind test would be good. Someone could have the two of exact same fins. Setup one with a maxi wing and the other with three vws. Then without the skier knowing what they are riding switch back and forth and have the skier evaluate each time.

 

It would also be interesting if there were some type of load meter on the pylon that could measure the accumulative load throughout the entire course to determine which setup required more physical energy to ski on.

 

Again, I believe the vws are helping people get more buoys, it is just that the older my body gets, the more I think about efficiently working it to make it last.

 

If I had to choose to ski a longer line for the rest of my life or ski extreme shorter line for just a few years and that was it, I would go for the long line for a long time. I know I am skiing more now without wearing out, and I think it is because the newer skies have less drag.

 

You might want to give the maxi wing a try. They are only $34.99 and that includes the shipping. If it does not work then bend it to 112° and trim it down to whichever size vw you want.

 

But then again, maybe there is more to it than just drag. I am not an expert.

 

[Wish]

It was funny to read the back and forth clarification comments regarding Goodes web page on the VW. Point proved. Absolutely confusing without a lick of good info unless you consider Dave Miller saying "Awsome" high caliber information (Dave M is truly awesome nothing against him). As to the drag comments it does add drag. The leading edge of the wing has a surface. Add more wings you add more surface, more drag. Now that may not be felt by the skier due to either the small amount of drag or the inrease in a positive performance attributes or both. But there is drag.

[Bud Man]

@OB, are you planning on taking your old wing off and setting up your fin with three vws?

[Wish]

I would love to know the specs on the wing degrees/measurements of the little one and I'll be skiing on it next week. Really want to try it!! Would like to experiment with diff degrees and sizes but need the specks on the little guy as a baseline. I seriously don't think I'll feel the drag but if you ask a pilot to add any kind of leading edge to a plane he will tell you drag will be added even if it improves performance in someway. Anyone have the specs??

[thager]

Wish, I think you're on the money. Must be made from Un-obtainium scrap from the F-111. If you take out the screws the VW just floats away into space? No weight, no drag, and no penalty! Sorry, I'm just a hack, but I call BS. You can't get something for nothing. If the ski has the correct surface area and is set up right you shouldn't need the crutch.

[Ed_Obermeier]

The next question is - how is an average skier like myself supposed to determine what type/size and how many of these wings are required, how do you determine proper placement, etc? Seems to me there needs to be a pretty detailed instruction manual with these things if the average skier is to determine with any accuracy and confidence how to correctly add one or more of these to their ski to achieve whatever benefits/improvements you're trying to achieve. Also seems that the degree of difficulty in obtaining optimum fin setup has just gone up exponentially. Apparently they have some merit - my question is how is the average skier to gain the knowledge to take advantage of that, short of painfully time consuming trial and error?

[Wish]

Goode web site should have something in their Tech section.......... Oh wait......ahhhhhh.......hmmm...........

[kstateskier]

I know a good web guy, someone should send his name and email to Dave Goode!

 

http://www.greyststudio.com

[MattP]

Yeah... I know a good one too... me lol

[Boody]

I jumped on the website ready to pull the trigger on the VW, but saw the $50, plust $14 shipping. Had to take a step back. Glad to hear OB likes its and I really do appreciate the posts and pictures. I may wait for a few more testimonials before I drop that kind of money on a tiny wing.

 

Honestly, not excited about adding drag even if it keeps the tip down. I don't have a problem with tip rise, but sometimes the ski doesnt finish underneath me like I want.

 

Keep the comments coming.