Originally Posted by Steve Ehlers

Sorry Guys ,NOT Impressed ! A factory original Regular or Super Kaos is Superior to this Overweight Pig ! (7-8.25 lbs)... The Test /Display shown here is not indicative of a really good SPA airplane ,however they may have used the recommended-ie., Prop that doesn't work well on a 2 stroke therefore low performance ..... Thumbs Down on 2 piece wing with wing tube = Wasted weight . Screw on tail feathers= Joke ....For glow power and espeically a 4 stroke mentioned= The front end will fall apart before the Covering starts peeling off= Sooner that you think !Because the intent of this plane appears to be too much E- Powered design ,i.e., Easily removal Hatch ..... Oh Barf on that one ...... Give me a break ......

Don't you think that's a little harsh, Steve? It's obviously not exactly what you want to see in a Kaos. However, it's my hope, and that of many others in the SPA, that it will provide a very welcome option for new folks who would like to try SPA competition but who lack either the building skills many of us older fellows take for granted or the desire to build.

You say it's an overweight pig - my primary SPA airplane weighs 7# 6 oz. Your comment about a 4-stroke knocking the firewall off - they supply hardwood triangle stock to reinforce the electric motor mount box. Install that behind the firewall with a little 30-minute epoxy and it should never fail. If you're worried about the bolt-on tail group, add some triangle stock. We'll see - I have mine pre-ordered and it will probably use an OS 91 Surpass 4-stroke for power. On the other hand, I might just throw an OS 61 FSR or a SuperTigre S-61 on it to be period correct as it won't be my competition airplane. Regardless, I'll report what mine weighs ready to fly and how it flies. I'll also report how well it lasts after I have some time on it. Heck, I might even post some photos.

FWIW - I own a very well used Tower Kaos 40 ARF powered by an equally well used OS 40 FSR swinging an 10-6 Master Airscrew prop. It needs recovering badly and is as ugly as sin, but I can assure you that it will easily fly the entire SPA Advanced pattern on 15% fuel. That plane is far more capable than 99.99% of beginning pattern fliers out there. I expect no less for the new Tower Kaos 60 ARF.

Jim

Originally Posted by ReelDoc

Like the quality of the Dirty Birdy ARF fuselage just aft of the wing trailing edge where it was so flimsy that I've personally seen 5 or 6 of them slap the tail against the wingtip after only one excursion off runway into the grass?

Jim

Not my experience with two DB ARFsI have owned and flown. Both with Novarossi .91 engines pulling them at 140+ mph. Snap rolls at that speed without airframe failure. Not bad.

So if you've personally seen 5 or 6 fail, statistically you should have seen at least 30 or 40 fly. Impressive pattern flyer numbers in your town. I should probably move there!!!

No pun intended, but let's keep this realistic.

The Kaos is a really nice sport plane. By no means a pattern plane IMHO.

Dave i have a few other patteren planes now, i fly more sport flying , i have always wanted the 40 size kaos but not battery hatch, iam just not sure what to expect with a 500 kv motor, i do have the FMS pattern plane that flys on 6 cells and a 500 or 550 kv motor with a 14x7 prop but it only weights 5.5 lbs.

Originally Posted by doxilia

Scott, my 2 cents worth is that you might be a little disappointed with classic pattern performance on 500 Kv motors using 6s. Unless..., you are flying a 120 size aerobatic model, or, you go to 8s+

David

Originally Posted by doxilia

That's a bit of an apples and oranges comparison since EDF's typically use inrunners which, by design, are high in Kv and typically much lower in torque (barring a gear reduction mechanism) than an outrunner.

One can spin up an EDF on an inrunner at 25K rpm or more without breaking much of a sweat current wise assuming the proper motor is used. EDF's get their thrust from small multiple blade fans turning very high RPMs much akin to a turbine.

My comments really reflect outrunner use turning props for classic pattern applications which I hoped was clear.

David

We've covered all this before David. If the objective is to turn an 11" prop at high RPMs like in the good ol' days, then we should pick the right tool for the job. If that tool happens to be an inrunner, so be it.

Originally Posted by yak13

I always liked the Kaos, but at this time I doubt I would like to fly one. It is a pity that Tower discontinued the excellent Dirty Birdy ARF to sub it for the Kaos. Definitely not in the same league. Not in performance, not in quality.

It is hard to tell what the logic is with the production of kits and ARFs sometimes.

One of the most popular kits to be built in the kit section of another website is the Great Planes Ultra Sport. Tower discontinued the kit and everyone on the forum went nuts and started a big campaign to get it back in production. They even set up a pre-order list to prove to Great Planes that the demand was real. After a year or two of work with Great Planes the Ultra Sport is available again.

Watching the Ultra Sport campaign with Tower and Great Planes it is a reality check that making money is a driving force. If they are going to make a production run of 1000 Ultra Sports they want to know how long it will take to sell them. One advantage of kits over ARFs for companies like Tower nowadays is the kits typically do not suffer the quality problems seen in the ARFs.

I think sometimes when ARFs come on the market everybody gets blurry eyed, goes nutty and starts buying them. But during that first part of the sales cycle the buyer's vision gets better and reality sets in along with disappointment. Bad reviews on quality get out and people stop buying them. Then like the Dirty Birdy Tower has to deeply discount the price to sell them. The savings they made on the material they used for the fuselage gets wiped out pretty fast at that point.

Oddly if they did a better job on the quality they would not have that problem, but they seem destine to keep repeating the same thing over and over. Way to they keep making ARFs with covering that falls off. They've got to know after all these years we hate that! Makes you wonder sometimes if the people designing and producing the ARFs even know anything about the RC hobby or if the ARF is just some unknown object that they are making on a production line.

Mike






.

i like the Great Planes Ultra Sport and wish it would be revamped into a electric friendly version. i dont have time to build a kit, life is to busy .

Originally Posted by cannondale1974

I thought whoever was flying looked pretty smooth. However, the video they did a few years ago for the Phoenix 7 ARF was incredible and that guy could FLY. I watched that video several times, beautiful 4 point rolls, slow roll etc.

The Phoenix was a Hangar 9 product (Horizon Hobby, not Tower/Hobbico), and the pilot was Mike McConville.

Andy

Originally Posted by scottc39

Dave i have a few other patteren planes now, i fly more sport flying , i have always wanted the 40 size kaos but not battery hatch, iam just not sure what to expect with a 500 kv motor, i do have the FMS pattern plane that flys on 6 cells and a 500 or 550 kv motor with a 14x7 prop but it only weights 5.5 lbs.

Scott,

I think your FMS model is probably a very good indicator of what performance you can get from that setup in a modern F3A type model. Unlike classics or even sport planes, the emphasis on current pattern is to have very high torque imparting a considerably higher thrust/speed ratio than what was, and still is, required for classic pattern. In the latter the ratio is inverted reason for which we often talk about ballistic pattern. Classic pattern is more akin to a pylon model setup than it is to a scale model setup as today's F3A models require.

Getting to the point, I was trying to comment that a vintage design like a Kaos, if you wanted it to fly like it did when used for classic pattern with a glow engine, you need to replicate that setup by using a higher Kv and current draw power plant. If you set it up with the same parameters that you have on your FMS model, but reduce the prop size and increase the model weight considerably, you'll wind up with a flying crate.

With that in mind, if you keep the Kv down, you need to up the cell count and reduce prop size for the Kaos compared to the FMS model. Conversely, you can keep the cell count the same at 6s but then you need to increase the Kv keeping the prop size more or less the same as in the 8s setup and that will also yield classic like performance.

Another way to look at it is to do it inversely, you set the power/weight ratio desired for the model - say 150W/lb. If you then fix the model weight say at 8.5 lbs you'd require roughly 1300W. From experience, these 60 size classics fly better at a slightly higher max power of 1400W+. Then, since power is the product of voltage and current (W = V x A), you can see that voltage and current have an inverse relationship given a constant power; increase voltage, decrease current or vice versa. If you then equate cell count to voltage and prop size to current, you can see where my comments above come from. Increase cell count, decrease prop size or vice versa. The motors Kv can be thought of as a constant multiplier in the equation. Increase Kv, increase power without having to significantly increase either voltage or current. I like to think of the metric as a sort of additive in fuel like nitro. You want more glow performance, increase nitro; you want more electric performance, increase Kv...

David

Originally Posted by AndyKunz

The Phoenix was a Hangar 9 product (Horizon Hobby, not Tower/Hobbico), and the pilot was Mike McConville.

Andy

Andy beat me to this comment. I was going to guess it was one of two folks at Horizon flying the model but since Mike was the driving force behind the product, it just seemed natural that he would fly the demo video.

David

Originally Posted by Jet_Flyer

........One advantage of kits over ARFs for companies like Tower nowadays is the kits typically do not suffer the quality problems seen in the ARFs........

With today's laser cutting, kits are pretty good. The weak link seems to be when the individual pieces get assembled overseas.

Originally Posted by Jet_Flyer

........Why do they keep making ARFs with covering that falls off? They've got to know after all these years we hate that! ........

I suspect that the average plane doesn't last long enough for poor covering to become in issue.

Originally Posted by Trisquire

We've covered all this before David. If the objective is to turn an 11" prop at high RPMs like in the good ol' days, then we should pick the right tool for the job.

Extensively, I agree. And yes, we do need the right tool for the job.

If that tool happens to be an inrunner, so be it.

IMO though, this is not the answer. Inrunners work well on DF's because of their low inertial mass compared to a prop. They also rely on multiple low pitch blades rather than two higher pitch blades like a typical prop does. Inrunners, simply put, don't have the torque required to turn a prop efficiently and generate the power required by themselves. They are used with some success in modern F3A with planetary gear reductions (notably motors like the Hacker C50 if memory serves) because modern pattern is more akin to scale in its thrust requirements than it is to ballistic pattern which requires or desires higher speeds.

Outrunners were sort of invented to overcome the torque issue with inrunners in prop applications. So there is actually nothing wrong with using outrunners for classic pattern. The only problem is that generally speaking we kind of insist in setting them up as one might for a scale or F3A model. Why? Because it gives lower current consumption, longer flight times while still delivering the thrust to fly.

But..., if we want ballistic pattern, there is no way around the need to increase Kv with the current state of the art which unfortunately demands higher current consumption and corresponding battery capacity.

So in a nutshell, for me, the right tool for the job with classics, all else being equal, is higher energy density battery chemistry. I believe that will come before or simultaneously with other developments in electric power.

Incidentally, this entire discourse on e-power parameters for classics vs modern F3A is directly akin to the concept of describing a piped two stroke vs a muffled four stroke. Another analogy yet, for me, is to think of Kv as a tuned pipe. Low Kv, no pipe, high Kv, pipe. Four stroke, big prop, two stroke, small prop.

David

Hi Guys,

I really love this forum in that you get to read the many opinions about ARF'S and KIT'S. I have been in this hobby like so many of us for a lot of years and have seen the transitions to ARF's from kit building for many of us. I have been somewhat ARF, ed....lol and still build, but mostly do restorations of the older classic pattern planes for my own enjoyment. Seeing and reading about this new KAOS that is coming out is very interesting in that it provides something for everyone. For those who want this classic but don't have time to build, it is a good thing. For those of use who are sticklers to the tradition of building may look at it as not being a TRUE KAOS. It's still a KAOS none the less either glow or electric powered. Well it may have some issues once it hits the field, like poor covering or a few bad glue joints, these thing can be corrected. Enjoy the fact that it has been reintroduced to keep the hobby/sport of RC flying moving forward. We have all had a favorite ARF or Kit come and go, that is the nature of the hobby industry, it's a business. I think we should appreciate the fact there is always something new coming out in the future which keeps the hobby going. If you want to build then do so, if you want to ARF, go for it. Let's enjoy

Ron

Here here! Agree. I build classic patterns for fun sport flying not competition so as long as I get enjoyment good enough. I'm getting 188 watts per lb. with 5s batts and having a great time. Plenty fast for sports flying. I just prefer the look of the classic pattern planes over the average sport model. No need to get so wound up.....

Dave i listed 2 motors i liked, the NTM 500 kv motor i have on have an did a watt test this morning using a 6 cell 20/30 c rated pack, i got around 1050 watts using around 44 amps, i also have a 35c rated pack that should give more power to, this was with a 14x7 prop , so depending on what the plane weights thats around 123 watts per pound or better if the plane weight less, iam thinking most motors with 500 kv will give around the same results, now were to get say a 600 kv motor that will take a 13/14" prop and get results like i have with the 500 kv.

QUOTE=doxilia;32593849]Scott,

I think your FMS model is probably a very good indicator of what performance you can get from that setup in a modern F3A type model. Unlike classics or even sport planes, the emphasis on current pattern is to have very high torque imparting a considerably higher thrust/speed ratio than what was, and still is, required for classic pattern. In the latter the ratio is inverted reason for which we often talk about ballistic pattern. Classic pattern is more akin to a pylon model setup than it is to a scale model setup as today's F3A models require.

Getting to the point, I was trying to comment that a vintage design like a Kaos, if you wanted it to fly like it did when used for classic pattern with a glow engine, you need to replicate that setup by using a higher Kv and current draw power plant. If you set it up with the same parameters that you have on your FMS model, but reduce the prop size and increase the model weight considerably, you'll wind up with a flying crate.

With that in mind, if you keep the Kv down, you need to up the cell count and reduce prop size for the Kaos compared to the FMS model. Conversely, you can keep the cell count the same at 6s but then you need to increase the Kv keeping the prop size more or less the same as in the 8s setup and that will also yield classic like performance.

Another way to look at it is to do it inversely, you set the power/weight ratio desired for the model - say 150W/lb. If you then fix the model weight say at 8.5 lbs you'd require roughly 1300W. From experience, these 60 size classics fly better at a slightly higher max power of 1400W+. Then, since power is the product of voltage and current (W = V x A), you can see that voltage and current have an inverse relationship given a constant power; increase voltage, decrease current or vice versa. If you then equate cell count to voltage and prop size to current, you can see where my comments above come from. Increase cell count, decrease prop size or vice versa. The motors Kv can be thought of as a constant multiplier in the equation. Increase Kv, increase power without having to significantly increase either voltage or current. I like to think of the metric as a sort of additive in fuel like nitro. You want more glow performance, increase nitro; you want more electric performance, increase Kv...

David[/QUOTE]

Originally Posted by cannondale1974

I thought whoever was flying looked pretty smooth. However, the video they did a few years ago for the Phoenix 7 ARF was incredible and that guy could FLY. I watched that video several times, beautiful 4 point rolls, slow roll etc.

You make my point for me. If you are marketing a pattern plane, then fly it as a pattern plane in the video. A pattern plane flown in an oval looks just like any other dopey plane. It does nothing to sell the airplane to it's intended audience. It should not take an act of God to find a pilot that can hold a line, and demonstrate the product doing what it was intended to do. Dang it!

Robert