Jeff Boyd 2

Hi Huison . .

Are there any results posted for this competition? Do you know if Patrawit Sookdee flew?

Cheers, JB

mariorevi

I fly the table P-11 and F-11. I use 4000 mha 10s 20C, no 8s. Reading the watts I do not have yet. I fly 10 minutes and consumption are for the 2500-2700 mha axi mha spends very little. You can use battery 4400 mha flightmax and 10s of your plane weighed only 100 grams more, all plane 4700 grams with 4400 mha 10s. I have batteries of many types and have weighed all.
Today I will make more photos and put them here ok?

Mario Reviriego

mariorevi

Huison2005 I recommend that you use the axi 5324/25, consumption is low and the potential is huge. I can get my wind up the sky and I have it clipped to 75Amps. Flighmax 4400 10s 20c are going very well but if you get a very light plane can put 4000mha quietly with the axi.

Recapitulation:

with 4000 mha flighmax - 4550 grams approximately
with 4400 mha flighmax.- 100 grams more.

Prop: PT model 20x13´´ or axi 20x13´´

huison2005

mariorevi ， thank you very much for the info ..... that 's really save me alot time to find info for this plane !!

I think i will go for the 44oomah flightmax 20c .... but than still , i need to wait for the PRO to arrive n weight check !

Motor will be Axi , same with your setup . . . .

Jeff , yes Patrik was there to flying with us , Malaysia team have 3 flyers . i am one of them .... guess what i am flying with the
WindS110 ... I think you should come n join the KING-CUP , we have had NICE dinner at Patrik restorant[sm=tongue_smile.gif][sm=tongue_smile.gif] Serve with THAI food ... yummi-yummi !!

Jeff Boyd 2

Mario . . thanks, I couldn't quite make out the number of balance wires in the pics. I would have been VERY surprised if you were running 4000 / 8S. That's even BETTER news for my weight expectations .

Huison . . If I knew you were going, I would have asked you to say hello to Pat for me . . we are old friends. He has invited me to the Kings Cup before . . one day I will get over there.

Cheers, JB

Velco

Hi Mario,

first of all congratulations, she is a beauty!

As I suspected the "problem" Wind 110 has with accelerating in downlines is repeated here.

I plan the same motor, can you please post some pictures about mounting, or was it just a straight bolt on?

Huison2005... plenty of info about 5325/24 here from the tester (Juan Rombaut) http://www.modelbouwforum.nl/forums/...5325-24-a.html , it seems to be more than enough.

The guy with counter rotating props was probably Michael Ramel, his web site is under construction unfortunately but there is a contact if someone might be interested http://www.f3a-e-factor.de/

mariorevi

Velco here in Spain it is night now. Tomorrow I will do good photos and put them here.

tommy s

My Feedback: (55)

Does anyone know if the production version of this airplane has a swept
wing or straight trailing edge wing ? I've seen pictures of it both ways.

tommy s

Jeff Boyd 2

Hi Tommy . . it has a straight TE.

The only swept wing version I have seen was Slivestri's flown at the WC's . .

Not sure if it's available as an option . . maybe for V2 ?

JB

cchariandy

Wing sweep is measured at the 1/4 chord not TE...that wing is swept.

Colin.

Velco

Looking at the photos it looks like that fuse is very thin around the central area with almost flat vertical lines. It reminds me very much of some Fliton designs like Element 30 and Inspire 60, 90 series where the fuse it self has some kind of profile for nice and controlled KE. My Element 30 feels more stable in KE than Angel 50. Hmm...

Jeff, please if you can, put some photos of both Wind 110 and S Pro fuse from the front. Would be nice to compare.

One more thing which came to my mind is that going lower kV, hence Axi 5330/24 or Hacker C50 15XL together with 22x12 (WE) would definitively help reducing speed in downlines. Ground clearance should not be the problem.

David Leitch

There's also the Miss Wind biplane with contra rotating props according to the Sebart website. Has anyone any experience of that one?

Velco

David, that baby is made by Oxai http://www.oxai-rc.com/main/detail.aspx?ID=51 At Sebart site the price was 3.500Euro (If I remember correctly). So far I have not found anywhere on the net anything about that bird.

Velco

luk3

Hi all,

Could you explain a bit your assesment? Just because of the lower KV or really because a bigger propeller? What about the brake programming on the Jeti Spin in order to reduce downline speed?

Kind regards

Velco

The straight forward answer would be because of a bigger propeller with reduced pitch.

Well, now I will try to explain a bit more. Probably I will write things almost everyone here already knows but from time to time telling a thing or two more doesn't hurt . I remember when I started with electro, not that long ago, I did not have a clue what everyone was talking about. It still makes me happy converting a "glow" guy into an "electro" guy and I believe that it is just the fear of the unknown that keeps more people moving to this, IMHO, far superior form of power. What an irony, I my self am a mechanical engineer !

So, kV or rpm/Volt: More Volts=more rpm on the prop. The thrust is generated by a rotating prop, more rpm = more thrust. Or, you put a bigger prop turning more slowly for the same thrust. But also bigger prop = more drag.

So as practically in the F3A the only constant are Volts, roughly 37V under load to be more precise, and as you need roughly 2,5-3kW to fly a 5 kg plane around with the authority therefore something in the range of 70-80 Amps is needed. That is already a high value as we do not use this power in very short burst but over a more prolonged number of seconds. I am saying this so that someone doesn't come to an idea to go down on 8S for a 5kg plane because then 100A would be needed, and that is really too much.

So, instead of having an outrunner with 235kV on 20x13 prop in order to have an adequate performance we can do the same thing with 190kV and 22x12 but with definitively better braking effect in down-lines as diameter has been increased and pitch reduced.

A programmable brake can further increase this effect, but it is always better to try solving the problem at its root.

And for the last thing, just after posting yesterday about lower kV idea I remembered seeing it somewhere already mentioned, and here it is on Hacker web site for C50 competition motors, http://www.hackermotor.com/images/Ca...%2036+37.pdf where Roland and Wolfgang Matt use C5014XL with 22x12 because "Best system for „Constant Speed“. Fits our flightstyle perfect". So, it is not my idea, but to me now it sounds very logical.

That would be my 5 cents.

Velco

luk3

Hi Back again,

that's much more than 5 cents to me, Velco.

I do however need some time to understand and tune up my ideas around the subject.

I'll be back soon, it is late here now

TIA

luk3

Hello,

I do understand now what you mean, Velco. A bigger diameter and less pitch propeller as a result of a lower KV motor in order to keep the same Amp range. Bigger diameter / less pitch propeller will surely help to slow down on downlines. I was not sure if you meant just lower KV as to provide less rpm on low throttle for any/same propeller.

That's when you still can choose what components to use, but once you have your motor already the choices are not the same. I agree on going first for root causes, but I question if the brake programming would be of much help in this case, from what i understand will give you some control on when and how to stop your propeller but not to keep it at a low rpm.

Thanks for your 10 cents.

GD

Velco

You are welcome,

I will try to further explain

1) The kV of the motor is completely irrelevant once the throttle is on 0.

2) A bigger diameter and reduced pitch will always cause more drag.

3) When the brake is set to off the the prop is spinning freely and is creating more drag than a prop which is not spinning at all. With a programmable brake we can choose in between off and 100% on, because a prop spinning at approximately 50% of what it could be if freely spinning is generating even more drag, interesting but true.

4) If you already have a motor then there is not much you can do except lovering your Volts. May be going to 9S. With this you will have to increase the Amps because we always need the same power, but, you will also be able to increase the size of your prop ...

5) Have fun experimenting ...

Velco

luk3

Yes Velco,

your are opening to me very interesting paths to go for experimenting.

I was thinking about "0.something" of throttle at lower KV but the different brake effects also open alternatives which I think they could only be validated after experimenting. Yes, I don't think a theoretical approach will provide enough and understable answers.

thanks again for another 10 cents.

huison2005

Jeff Boyd 2 , here are some pic at the THAI "KING-CUP" ...... Mr.Patrick is standing beside me "me " is at the middle one , tall guy ....

Velco

The only way to really comprehend the problem would be to equip the plane with an E logger together with an Airspeed expander ( a Pitot tube) and rpm sensor. Like this an actual speed in downlines can be measured together with the prop rpm and the influence between values fully understood. Also, like this one can tune different planes to behave equally, making practice on different planes easier.

luk3

Yep!

Thks

GD

mariorevi

Hey guys, here I leave a few photos ...

mariorevi

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wingster

My Feedback: (26)

Mario

Who makes the spinner?

John