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Old Nov 05, 2012, 05:04 PM
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Yello,

I agree that "depending" on how my first post is read, it could look like I was telling 1W-40 or 16/40/1 guys to prop up 5.25X6.25

I will add a word or two to help ensure it can not be read that way.


Thank you,

Gryphon
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Old Nov 06, 2012, 12:45 AM
310mph Kolibri T25 Swist
henke's Avatar
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Quote:
Originally Posted by Mreyello View Post
Dont you think its worth to think about improvement options beyond just adding batterys and amps?

Yello
As beyond as it gets now days. And it runs hotter then the HET too




I use the formula P=F*V

lets say my Swist goes 290mph level with 7,3lb of thrust.

33N*133m/s=4400watts needed at 100% eff. I assume a setup like this runs about 2/3 eff which makes it 4400/0.67= 6600watts input to challenge my speed.

Looking at the F3S planes they seem to need powerlevels around there to reach 300mph.

If it's 100% correct I do not know but it's a good rule of thumb I think.
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Old Nov 06, 2012, 12:55 AM
310mph Kolibri T25 Swist
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Originally Posted by sebbe View Post
and what rpm/pitchspeed is needed to get to 235mph ?
50krpm on a 4.75" prop makes of only 100m/s which is only 223mph.

use the frequency of the video to determine the rpm during flight

Use SPL to snag the frequency ( https://play.google.com/store/apps/d...SPLMeter&hl=sv )
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Old Nov 06, 2012, 04:01 AM
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Quote:
Originally Posted by henke View Post

33N*133m/s=4400watts needed at 100% eff. I assume a setup like this runs about 2/3 eff which makes it 4400/0.67= 6600watts input to challenge my speed.
As long as most of the guys around here watch big wide fuses as an advantage,or 1100g F5d as light or watch servocover-kennels and batlleship linkages as sexy and big ugly air intake ducts(in low presure areas) as effective i have to confirm your calculation

Yello
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Old Nov 06, 2012, 05:19 AM
Crashing into the sky!
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hehehehe
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Old Nov 06, 2012, 05:51 AM
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I think that everybody is underestimating the drag penalties on fast planes. More specifically, how much speed fat fuselages, servo covers, and other things are taking away. I believe it is significant.

I am going to attempt to match the speed krproton got from his viper Using the identical(not same though) power system in my jolt. I've been able to look at a viper and the frontal area difference is significant - I would estimate the jolt is perhaps 50% more. I am guessing this will result in at least 10mph less speed and perhaps as much as 20mph less.

Quote:
Originally Posted by Mreyello View Post
As long as most of the guys around here watch big wide fuses as an advantage,or 1100g F5d as light or watch servocover-kennels and batlleship linkages as sexy and big ugly air intake ducts(in low presure areas) as effective i have to confirm your calculation

Yello
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Old Nov 06, 2012, 07:25 AM
310mph Kolibri T25 Swist
henke's Avatar
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Quote:
Originally Posted by Mreyello View Post
As long as most of the guys around here watch big wide fuses as an advantage,or 1100g F5d as light or watch servocover-kennels and batlleship linkages as sexy and big ugly air intake ducts(in low presure areas) as effective i have to confirm your calculation

Yello
Easy beeing cocky, remember my plane is the fastest by like 130kph with no flutter... Right or wrong engineerd
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Old Nov 06, 2012, 07:55 AM
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Nothing wrong with your engeneering, it obviously works.
You added let me say 30% drag and added 200% trust.
But as thrust may be limited for most of us ,dont you think its worth also to think about reducing drag?

Yello
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Old Nov 06, 2012, 08:10 AM
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For what its worth I got some speeds that I was proud of with my viper. Was at a big flyin and finally got some good readings on the radar gun with my 5S setup. I hit 235mph as my final number. I can honestly say that this is probably the most that I can get out of my setup I have. It was crazy fast and much faster on 5S. Figured I would post that up since we were talking about planes going above the 230mph mark. And this was NOT a straight line pull. I go full power, 45 it, half roll, make the biggest half circle I can to bleed off as little speed as I can and then fly flat and level for about 200 yards before passing by the radar gun that is right next to me.
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Old Nov 06, 2012, 08:26 AM
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Big lipos need space and weigh alot.
How else do you go fast ?

Quote:
Originally Posted by Mreyello View Post
As long as most of the guys around here watch big wide fuses as an advantage,or 1100g F5d as light or watch servocover-kennels and batlleship linkages as sexy and big ugly air intake ducts(in low presure areas) as effective i have to confirm your calculation

Yello
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Old Nov 06, 2012, 08:55 AM
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The 52 sec run i mentioned in post 1549 was scored with 5S 1550mah.

Yello
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Old Nov 06, 2012, 09:44 AM
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Henke,
Are your blades on the engine slightly scratched or damaged? The picture looks like the leading edges are not normal about 1/3 the way in from the outside????
Maybe you ingested a bug into the engine.
Erik
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Old Nov 06, 2012, 11:59 AM
Drinks Day Old Expired Milk
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WOW ! This thread turned into a mess ! .......Now i will go back to LAUGHING MY OFF ABOUT SHORT 28mm MOTORS PULLING SOME OF THESE CLAIMED SPEEDS.....Also,lets keep in mind,this is the Swist thread.
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Old Nov 06, 2012, 12:35 PM
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Quote:
Originally Posted by VooDoo Child View Post
WOW ! This thread turned into a mess ! .......Now i will go back to LAUGHING MY OFF ABOUT SHORT 28mm MOTORS PULLING SOME OF THESE CLAIMED SPEEDS.....Also,lets keep in mind,this is the Swist thread.
I would like to know exactly why you dont think these planes are able to reach these speeds with the 1115/1Y.
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Old Nov 06, 2012, 01:03 PM
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Guys, lets keep it real, as otherwise this will be my father is stronger then yours playground soon..

The Swist with the 1w-40 motor and 4.7apc prop did have a really clean doppler at +230mph, no doubt, there was no wind to advantage the speed, BUT the speed was out of a dive.. this pass I can for sure say is real speed as both the speedgun and doppler are precise.. how fast is it without dive ? well maybee 220? 225? who knows..

Smoothflying, remember, when you did a measure with speedgun with 4s, if I remember right, the speedgun showed much more then my doppler, Right ?

It would be fair to let me analyze and doppler that video of when you are flying 5s..

also keep in mind, the Swist 5s typhoon motor is a 3300kv, thats pretty hot on 5s..

Doug, YEAH, its a battlefield, and playground also for big kids
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