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Old Oct 07, 2012, 01:48 PM
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Here is my masterful artwork. LOL
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Old Oct 07, 2012, 01:57 PM
"The Judge"
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Sebbe being sort of a Newb. I have a question for you. I've been in GS for a very long time and know with GS that a lighter plane does fly better but then it gets to a point where to light just doesn't fly to well when you start adding in wind and such. My question is doesn't weight play a huge game with these planes? Can adding bigger batteries and extra batteries add weight to where the plane wont just go as fast? From speaking with soaringusa 5s on the 1115 1y in the Viper should get it to at least 230mph. I believe that. I've flown pylon racers in the 150-180 range and I will definitely tell you this plane is night and day faster. I am going to try and make picture of my 217mph pass so you can see how we got that speed.
I dont know how weight comes in play, what I dont think I know, I better keep quiet

I dont know how fast the Viper is compared to other same class F5D ships, Im sure its fast enough, not slower then others, but as I said, I think the setup has more important matter then a new modern F5D plane shape has...

I have seen many "proof" of the Viper doing around 200mph with 1800 watts static input on the 4.75x4.75 prop, for example: mega 16/35/1 is a classic example with that prop on 4s.... BUT the strange thing is , your NEU is only 2800 kv, right ? the mega 16/35/1 is 3550kv, its a HUGE difference , so if yours Viper is going 200mph flat and level on a 2800kv motor and 4s, how come the MEGA motor on 3550kv on 4s only does the same 200mph ? THIS is where I dont get it ??

In a DIVE and maybee some tailwind measured instant speed like a speedgun, YES, it could be 217mph, could be , I dont know... but FLAT and LEVEL, NO wind, I am saying with that neu motor on 4s and that prop = 170-175mph...

But go ahead, prove me wrong

I can say one thing for sure, when it comes to estimate speed, IM pretty good
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Old Oct 07, 2012, 02:51 PM
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Terry, for example, VooDoo:s Swist did close to 200mph on a 2500kv motor on 5s and 4.75x4.75, and he did fly a bit away from the phone, making the numbers less then thay are + he could go a bit longer runs to really gain som rpm:s... I think its fair to say that setup is a maximum 200mph setup, no more... even if did get some lower readings like 193-194mph, I think its quite sure to say he could get a 200mph run by makinging a longer run closer to the phone, no more, but 200mph is possible, thats all Im saying...

So now all we need is to know how much static is that setup and how much in air, and we have our answer, written in blood, no theoretic calculations and suggestions, as we know that doesent goes with reallity anyway..

So Doug, how much wattage was it static and in air with that mega 2500kv motor on 5s ? and we have out answer what it takes to reach top 200mph in a GOOD run CLOSE to the phone...

Sebbe
I know how fast Mega 16-35-1.5RE (2500kv) on 6S with 4.2X5.5 is...and lets not forget,i know how fast a Neu 1115/1Y 2700mah 65c 5S w/apc 4.75X4.75 is That setup is in the swap shop for sale now.
Swist F5D with New Neu. (2 min 47 sec)
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Old Oct 07, 2012, 02:57 PM
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Please understand I'm not saying flat and level I'm running 217. From my picture above I am running 217. Flat and level I'd agree with everyone I'm probably at 180+
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Old Oct 07, 2012, 04:46 PM
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That same gun 2 weeks ago was used to clock a speeding car going by it. The car was going by at 75mph on its speedometers and just so happened that the gun said the same thing. So good buddy. I'm sorry you are so much slower than me on 4s. Maybe you should get a Viper. You do have to remember your Swist is much heavier than mine. I guess in 2 weeks we will get together at the huckoween and find out. I can't wait to see my good buddy again.
You know i am just having fun But i did get a PM,that part i was not playing....And just so you guys know,that video of my Swist doing 210mph,and the video that says "found more power" I am running the Outrunner on 6S.
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Old Oct 07, 2012, 04:54 PM
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Any comparisons on speed with the same setups

Jolt vs. Viper vs. Swist?

In other words, is one of the airframes considerably faster than the other?
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Old Oct 07, 2012, 05:19 PM
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Any comparisons on speed with the same setups

Jolt vs. Viper vs. Swist?

In other words, is one of the airframes considerably faster than the other?
That's what I'm trying to figure out. I do know from the weights shown on the soaringusa site it shows the Swist as being a lot heavier than the Viper. I'm wanting to look at Voodoos Swist and make some guesses that are in my head about the Swist. Nothing bad. I do know his saddle is much wider which would take a bigger battery. Not sure if bigger is better. Just keep thinking about the weight game with these planes. I could be way off or dead nuts on. I do know less drag does equate to going faster. I think we would all agree on that statement. LOL I have friend that has a jolt but I was very new to these planes and just didn't think to compare. He did say there was a lot less work involved in building my Viper compared to his Jolt. So the thinking goes on.
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Old Oct 07, 2012, 05:40 PM
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Guys, that pitch speed calculator isn't wrong. Pretty simple calculation really and there are lots of other calculators that will give you the same results.
Variables that come into play are is the pitch of say a 4.75 prop really 4.75? How much is it loading the motor? How much slippage is there? How efficient is the prop? etc?

Also look at a fully charges 4S battery which is 16.8V and if your KV is 2600 that means at peak battery you will get 43680 rpm with no load. Loaded less and when it unloads on the air about that rpm or less. 43680 on a 4.75 pitch translates to 196 MPH. And we know that your batteries aren't going to be at 16.8 after you launch .
So lets say they are at 15.5V, thats 40300 rpm, which is 181.27 mph.
Now we have to take into account prop slippage and looses from the airframe.
So it is possible that the pitch of the prop is greater than 4.75.
To convince me that this motor would go over 200 mph I would need to see the log of the run and things like A's, RPM, Volts.

I'm running 3250KV on 4S and 4.7 prop, In flight data is 14V about 43000rpm and 1250W with a Graupner 4.7 x 4.7 on my XPlane. that calculates out to 191 mph. This is all straight and level. I have also tested APC 4.75 x 4.75 and it doesn't seem as fast.

What I'm fining interesting with these new props that are coming out of Ben and Rolf and the outrunner testing Doug has done, is you can really lower the KV and RPM keeping everything much cooler yet still get 200++MPH. Be it an inrunner or outrunner.

I guess the rev 1/2 cuban you did entering where you did the radar check would have had some effect on the top speed.

Terry
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Old Oct 07, 2012, 05:54 PM
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Top speed is what I'm talking about. Not race track pattern at level flight. And I do know the prop speed and rpm will go up a great deal in the air. The prop is able to unload more. That's why you get that increased whine when coming out of a dive vs running tge motor up on the ground.
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Old Oct 07, 2012, 06:07 PM
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I just looked at my logs again and the rpm increase is less than 800rpm static on the ground to fully unloaded in the air. So it isn't as significant as you would think with the tiny props.

Terry
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Old Oct 07, 2012, 06:12 PM
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Smoothflying, which flyin will you and voodoo be at?? Hodges? If so I'll come for a day and we'll throw mine up as well/

Terry
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Old Oct 07, 2012, 07:48 PM
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Smoothflying, which flyin will you and voodoo be at?? Hodges? If so I'll come for a day and we'll throw mine up as well/

Terry
Huckoween in Iron City, GA. Its a 3D flyin. Let me know when you will be at Macs again. I will meet u.
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Old Oct 08, 2012, 04:29 AM
"The Judge"
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johnnyrocco123 , I dont think there is a BIG difference in speeds between modern F5D airframes like the ones you mentioned...

terry, many numbers there what I do know, that has been proven many times is that you need around 1800 watt static with a good efficient motor like NEU, mega or similar to reach 200mph level.. I think there are a few factors that are hard to count in theoretic calculators...

example:

motor: inrunner 1810kv 73 gram heavy, pretty efficient, 3s lipo 1300mah 25c, APC 7x5 prop, how fast woud a small airframe pretty slick go with this setup you think ?

Airplane: het rc Jack the rabbit..
motor:
http://aircraft-world.com/prod_datas...cer/bl4-15.htm

Take a guess ?

I have the speed dopplered many times, straight and level..

You will be surpriced how "off" it could be..
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Old Oct 08, 2012, 06:32 PM
You down with EPP?
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I'm ordering a Swist. I would love to be flying it by Thanksgiving.....
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Old Oct 08, 2012, 06:42 PM
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I'm ordering a Swist. I would love to be flying it by Thanksgiving.....
Sure hope you have some 2700mah 65C 5 cells to fit in there no problem Or 2250 6S 2X4 ....and do not worry,the Swist airframe is just as fast as the Viper,if not faster with the newer wing design and minus the big old T-Tail up in the air .
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