[Kawa Hovercraft]

Hi,

We will have a brand new sickle shaped blade setup available to see, hug, touch and smell at Hoverally. This fan is brand new to the market and was just released 3 days ago. Approved for use in hovercraft applications. WOW. This fan is a totally radical design. Must see! Come to our tent, look for the black and white banner! We will have an assortment of fans for display.

Nate Kawa
Kawa Hovercraft LLC
Distributor for Hascon Wing Fans for the hovercraft industry.

[kach22i]

Nate, you know a bunch of the people here want to see numbers and direct comparisons to the existing standard (MW), be prepared.

From what I've read the other sickle shaped blade (unless it's the same one) on the market makes a little less noise with no loss in thrust. Can you tell us if this is the case with your new blades?

[ken]

Nate, you know a bunch of the people here want to see numbers and direct comparisons to the existing standard (MW), be prepared.

From what I've read the other sickle shaped blade (unless it's the same one) on the market makes a little less noise with no loss in thrust. Can you tell us if this is the case with your new blades?

Sorry to start picking nits, but this statement is really misleading.

No loss of thrust compared to what? Compared to another Hascon fan, or compared to a MW fan, or compared to a XYZ brand propeller, or what?

[kach22i]

Sorry to start picking nits, but this statement is really misleading.

No loss of thrust compared to what? Compared to another Hascon fan, or compared to a MW fan, or compared to a XYZ brand propeller, or what?

I don't know all the makes and models off the top of my head, but I did say a MW fan. Let me use the search function and find that old thread. I don't know what Nate has so it's going to be apples to unkown oranges anyway.

EDIT:.....................................................

http://www.hoverclub...n...&hl=website

..............ask about the new sickle blades.................

From that old thread:

WINGFAN........
http://www.wingfan.c...ex.html?lang=us

> 50% noise reduction with series S sickle profile

* 3 different blade profiles (S2 + S4 + S6)
o covering diameters from 16 to 48 inch

* Noise reduction of up to 4 dB(A) at the same air flow rate
o in comparison with the well known airfoil profiles.

* Cost advantages due to fewer number of blades
o with wider profile.

* Actual results of > 1 dB(A) overall system noise reduction
o as measured by customers with engine applications.

From the USA WingFan website:
http://www.mw-americ...ducts/index.htm

Product Range
The Multi-Wing System is based on providing a custom solution to your air moving problems from standard components. Offering high efficiency airfoil profile blades and low speed, low noise, broad paddle profile blades, in a variety of engineered thermoplastics and cast aluminum, in any diameter from 7 to 78 inches, with mounting to your specific requirements, enables the Multi-Wing system to custom tailor an impeller to meet your exact requirements at off the shelf pricing.

In short, the Multi-Wing System can provide a solution to the problems of virtually every air-moving application.

This post has been edited by kach22i: 19 June 2007 - 12:53 PM

[ken]

George,

I'm not trying to be tiresome. There are just a lot of variables, and a lot of it matters for this discussion even if most of us (me too) don't have enough knowledge in that area to even say what those variables are. Some of them might be duct characteristics (length, tip clearance, diameter, leading edge radius, etc), horsepower, relative airspeed, offset angle of the relative airspeed, and that's just stuff a layman like me can think of off the top of my head.

Any time you change anything about an airfoil, you change a lot of these odd characteristics. They might not matter to the normal MW customers, but these things might matter to us. IMO, the only way to find out whether it works better or worse on your particular hovercraft is to compare two of that type of hovercraft on the same terrain, with the same driver. Or drive it with one, and then swap fans and drive it with the other. At least, there would be a difference for different types of craft, and different types of use.

[kach22i]

My next blade will be some sort of whale flipper thing, what do I care anyway?

Link:
http://www.hoverclub...?showtopic=1172

This post has been edited by kach22i: 19 June 2007 - 01:49 PM

[hman]

I don't know all the makes and models off the top of my head, but I did say a MW fan. Let me use the search function and find that old thread. I don't know what Nate has so it's going to be apples to unkown oranges anyway.

EDIT:.....................................................

http://www.hoverclub...n...&hl=website
From that old thread:

WINGFAN........
http://www.wingfan.c...ex.html?lang=us
From the USA WingFan website:
http://www.mw-americ...ducts/index.htm

Up until the late 80s the cooling fan for the air-cooling in a Porsche 911 was a small, semi-ducted fan with about 11 blades that turned about twice engine rpm. They were fairly noisy - or delightfully musical - depending on the mindset of the listener. From about 1990, they were replaced with curved blades and the distinctive sound mostly went away. But the fan needed slightly more power because curved blades are less efficient, all things being equal.
I think the blurb from Hascon said that the curved blades make less noise at similar airflow to the current shape. They did not mention power consumption. But if they are really quieter, I would take that deal.

[Kawa Hovercraft]

Hi,

Really, like Ken says, there are so many variables that can make a fan work, work really well or not work very well at all. The hard numbers can be deceiving because things change depending on it's application especially in hovercraft. Hascon's in particular have a solid reputation in Europe for being great fans. Here, many Scat owners are turning to Hascon's over there older type systems and we are finding that they really do make a difference, big differences in some cases. Of course this would depend on the type of fan system you are replacing and the overall efficiency of the hovercraft in question's design itself.

For example, axial impellers like MW's or HW's, in my opinion are the better choice for lift systems in twin engine or twin fan craft, why? Because they equal or exceed wooden props for a number of reasons like (but not limited to): static pressure, affordability, longevity and ease of maintenance. And, once you buy a wooden prop you can't change it. What if you were to upgrade a craft from a 5 hp lift motor to a 12 hp lift motor? You would need to buy a new prop. Ok, now out money for 2 props If you use an adjustable pitch fan like a MW or HW you can reuse the same fan for the new motor by changing the pitch. That's just an example in practical terms.

Now, I will have to say that not all props are bad, certainly not. In fact, in many cases, props outperform axial impellers in thrust only apps. Not to say you can't find a fan to do the job a prop does.

In an integrated craft such as a Scat which are 20 plus year old design, small fan (and 20 plus year old fan technology), etc and usually underpowered, they can need all the help they can get. This is where we see the biggest gains in performance with Hascon's. Not to say a Scat is bad, that is how I got my introduction to hovercraft and have owned several myself.

Efficiency gained can be in several areas, not just thrust output. Faster spin up, reduced fan stall, blade strength, etc etc can be factors when talking about efficiency. Lots to say and very little time before Hoverally so I got to cut this short now, BUT, come on by our pit area and have a look and we can chat more.

Happy hovering.

Nate Kawa

Oh yeah, another thing, MW's sickle blades are not suitable for use in hovercraft. Neither MW or Wingfan for that matter will sell them for use in hovercraft. The material and sweep is too flexible. The fans I am bringing is like a sickle shape but also like a wavy lays potato chip AND TESTED AND APPROVED for use in hovercraft. See the picture:

Attached File(s)

•  sa_sito.jpg (298.17K)
  Number of downloads: 59

This post has been edited by Kawa Hovercraft: 19 June 2007 - 08:23 PM

[ThrustProp]

Wow, do those waves act to stop the centrifugal bleed?

Hi,

Really, like Ken says, there are so many variables that can make a fan work, work really well or not work very well at all. The hard numbers can be deceiving because things change depending on it's application especially in hovercraft. Hascon's in particular have a solid reputation in Europe for being great fans. Here, many Scat owners are turning to Hascon's over there older type systems and we are finding that they really do make a difference, big differences in some cases. Of course this would depend on the type of fan system you are replacing and the overall efficiency of the hovercraft in question's design itself.

For example, axial impellers like MW's or HW's, in my opinion are the better choice for lift systems in twin engine or twin fan craft, why? Because they equal or exceed wooden props for a number of reasons like (but not limited to): static pressure, affordability, longevity and ease of maintenance. And, once you buy a wooden prop you can't change it. What if you were to upgrade a craft from a 5 hp lift motor to a 12 hp lift motor? You would need to buy a new prop. Ok, now out money for 2 props If you use an adjustable pitch fan like a MW or HW you can reuse the same fan for the new motor by changing the pitch. That's just an example in practical terms.

Now, I will have to say that not all props are bad, certainly not. In fact, in many cases, props outperform axial impellers in thrust only apps. Not to say you can't find a fan to do the job a prop does.

In an integrated craft such as a Scat which are 20 plus year old design, small fan (and 20 plus year old fan technology), etc and usually underpowered, they can need all the help they can get. This is where we see the biggest gains in performance with Hascon's. Not to say a Scat is bad, that is how I got my introduction to hovercraft and have owned several myself.

Efficiency gained can be in several areas, not just thrust output. Faster spin up, reduced fan stall, blade strength, etc etc can be factors when talking about efficiency. Lots to say and very little time before Hoverally so I got to cut this short now, BUT, come on by our pit area and have a look and we can chat more.

Happy hovering.

Nate Kawa

Oh yeah, another thing, MW's sickle blades are not suitable for use in hovercraft. Neither MW or Wingfan for that matter will sell them for use in hovercraft. The material and sweep is too flexible. The fans I am bringing is like a sickle shape but also like a wavy lays potato chip AND TESTED AND APPROVED for use in hovercraft. See the picture:

[ken]

Hi,

Really, like Ken says, there are so many variables that can make a fan work, work really well or not work very well at all. The hard numbers can be deceiving because things change depending on it's application especially in hovercraft. Hascon's in particular have a solid reputation in Europe for being great fans. Here, many Scat owners are turning to Hascon's over there older type systems and we are finding that they really do make a difference, big differences in some cases. Of course this would depend on the type of fan system you are replacing and the overall efficiency of the hovercraft in question's design itself.

For example, axial impellers like MW's or HW's, in my opinion are the better choice for lift systems in twin engine or twin fan craft, why? Because they equal or exceed wooden props for a number of reasons like (but not limited to): static pressure, affordability, longevity and ease of maintenance. And, once you buy a wooden prop you can't change it. What if you were to upgrade a craft from a 5 hp lift motor to a 12 hp lift motor? You would need to buy a new prop. Ok, now out money for 2 props If you use an adjustable pitch fan like a MW or HW you can reuse the same fan for the new motor by changing the pitch. That's just an example in practical terms.

Now, I will have to say that not all props are bad, certainly not. In fact, in many cases, props outperform axial impellers in thrust only apps. Not to say you can't find a fan to do the job a prop does.

In an integrated craft such as a Scat which are 20 plus year old design, small fan (and 20 plus year old fan technology), etc and usually underpowered, they can need all the help they can get. This is where we see the biggest gains in performance with Hascon's. Not to say a Scat is bad, that is how I got my introduction to hovercraft and have owned several myself.

Efficiency gained can be in several areas, not just thrust output. Faster spin up, reduced fan stall, blade strength, etc etc can be factors when talking about efficiency. Lots to say and very little time before Hoverally so I got to cut this short now, BUT, come on by our pit area and have a look and we can chat more.

Happy hovering.

Nate Kawa

Oh yeah, another thing, MW's sickle blades are not suitable for use in hovercraft. Neither MW or Wingfan for that matter will sell them for use in hovercraft. The material and sweep is too flexible. The fans I am bringing is like a sickle shape but also like a wavy lays potato chip AND TESTED AND APPROVED for use in hovercraft. See the picture:

Speaking from personal experience, the weight of a prop or fan makes a lot of difference in how fast your craft spools up or shuts down. For thrust, you get a torque roll when you hit or release the throttle, obviously more pronounced with more power. I had (still have, as a spare) an especially heavy prop that I could squeeze the throttle and cause the craft to spin around, because it dipped one side into the water and bled air out the other side, enough to cause a spin. Fun, but not what you want on your hovercraft.

That ripple blade is interesting, Nate. Does it reduce noise as well? Can you point us at a specifications page?

[kach22i]

The fans I am bringing is like a sickle shape but also like a wavy lays potato chip AND TESTED AND APPROVED for use in hovercraft. See the picture:

I was just about to invent one of these.

Really, that fan looks like a cross between a sketch I did a while back and the whale blade from Canada.

http://www.whalepower.com/drupal/

This post has been edited by kach22i: 20 June 2007 - 10:29 AM

[kentgano]

Seems like a copy of the Fire Blade set up I have been running for some years now.

This post has been edited by kentgano: 20 June 2007 - 10:39 AM

[kach22i]

Seems like a copy of the Fire Blade set up I have been running for some years now.

I did not know this, looking for some better pictures though.

http://www.revtechho....aspx?tabid=732


EDIT:


http://www.revtechho....aspx?tabid=730

Revtech International Pty Ltd............Development of "FireBlade" swept hollow-blade fan

http://www.hoverclub...p?showtopic=910

Nice fan and splitter.

This post has been edited by kach22i: 20 June 2007 - 12:41 PM

[rennickr]

Hi,

We will have a brand new sickle shaped blade setup available to see, hug, touch and smell at Hoverally. This fan is brand new to the market and was just released 3 days ago. Approved for use in hovercraft applications. WOW. This fan is a totally radical design. Must see! Come to our tent, look for the black and white banner! We will have an assortment of fans for display.

Nate Kawa
Kawa Hovercraft LLC
Distributor for Hascon Wing Fans for the hovercraft industry.

Nate,

I realise that you were unable to show your new fan at Hoverally, but can you supply us with some performance & pricing details? Have you had a chance for a direct comparison with your Hasconwing Fans?

Bob

[Kawa Hovercraft]

Yes, unfortunately the fan had not arrived in time to have at the rally. I'm a bit embarrassed by that but that's the way it goes sometimes.

The fan is being talked up as being 60% more efficient than Hascon's best as of right now. And of course, Hascon does seem to have the edge over MultiWing's 5Z blades and is gaining lots of respect both here and abroad. I've tested MW 5Z against Hascon and compared side by side extensively and agree Hascon's the best choice right now for most all hovercraft applications. And so, back to efficiency claims. Efficiency can mean a number of different things. Is it quieter? Is it stronger? Does it mean more airlow? More pressure? Does it mean it requires less hp to do the same thing as another fan setup? etc, etc. All these things are promised in part by the manufacturer. However, my contact says the information we in the hovercraft are awaiting is whether or not, or which applications or not, will they work? Now, I've been told they were tested in a hovercraft and approved for use in hovercraft and the new fan was coming. But still as of this writing they are still nervous about actually selling them into the hovercraft market. I don't have the reason's why that is the case but I am working hard to get the answers. I think it's just a matter of of them being confident in reviewing test data and then ultimately, putting one in a Trans Aero and giving it a whirl.

There still may be hp limitations and the usual diameter limits, etc. The price will be higher than Hascon's currently but as far as fans go, very reasonable. I should know the answers to my and your nagging questions about this promising fan very soon. I hope that helps.

Nate Kawa

Nate,

I realise that you were unable to show your new fan at Hoverally, but can you supply us with some performance & pricing details? Have you had a chance for a direct comparison with your Hasconwing Fans?

Bob