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Old Oct 02, 2012, 09:25 AM
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Now I have finally tested the climb.
First climb, into a 10mph wind, it took 10 seconds to climb to 100m and be 150m up wind.
The second climb was from 10 to 90m (straight up - but into the wind) and that took 6 seconds.
Then it rained again.
The plane flew for 15mins from these 2 launches. It is all powered from the same battery.............. The recharge took 309mAh - a portion must have been used by the radio.
I am very happy with that - - 2 x 15 min flights = 600mAh ............. You can take that out of a 850-3S.

Or, as it takes 10 seconds to change. 1 pack in the plane, one in your pocket and one on charge.
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Old Oct 14, 2012, 08:46 PM
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LI, New York, USA
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I am going to join the thread. I just purchased George's (Saltyone) Supra Fuselage, so I am going to hang around and learn before I try to fly it.

Up until now I have been flying a Radian in ALES contests. Time to step it up I guess.
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Old Oct 25, 2012, 12:20 AM
Tragic case
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Sydney Australia
Joined Feb 2002
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Just to add that I am trying three different motors a Kontronik 480 + 5:1 (excellent power a bit on the heavy side), a Kontronik 400 + 5:1 and a Reisenauer gearbox on slightly hot Scorpion motor.

I've yet to test the latter two. I plan to try and keep the props relatively small. Its clearly less efficient but I don't care about efficiency any more and the small props provide a cleaner front end once you turn the power off.

I'll post some results eventually when its all installed. Have to build a new maxa first. I had a transmitter failure (a regulator blew up in the tx and it instantly died completely) causing a complete loss of model. The good news is I have the new fin so can put the servos in the tail fairly easily.

Had I known of the new 6.7 box that would have been tempting. However must say the Kontronik service has been excellent with quick delivery of the motor. Also I'm a big fan of the Kontronik ESC and the 55 amp model is a good fit.

This thread is about motors but I can't agree that the Maxa is only a light wind model. It has a low wing loading and a slightly thicker foil than the Supra but I flew it in strong winds in competition and was able to penetrate (slowly). Its excellent handling is a big help in that regard.
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Old Oct 25, 2012, 02:57 AM
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David, I said the Maxa is superb for light weather work, and it is. I have a 4M Ava @ 6oz/sq ft and the Maxa @ 7.4 oz. I have still not confirmed which is the best in totally flat air - but, as soon as you can feel any air movements (indicating lift) the Maxa is better.
If I did it over again, the servos would not be in the tail and it would now be lighter.
Yes, the Maxa can be made to handle more wind, but how efficiently ?
The Pike Perfection was a miscalculation - I had figured it would come out about 2kg and the way it is, you have to use what will go in and it ended lighter.
As the wind builds, the Perfection (for me) just feels better to fly.
I still fly a Graphite D-box @ 9oz but the Electra @ 9.5 oz starts to get better in a blow.

In my field, it gets a bit bumpy as the wind rises (trees and things) and the greater speed and higher wing loading make landing better / smoother.

As this is a Supra thread, I would say buy 2 - one being the lightest they make and the other the heaviest. Build the lightest as light as possible and the heaviest - heavy.
For flat calm, the only task is to climb to 200m and hang there as long as possible. For windy days you want to be able to climb to wherever in the sky looks best, and if you got it wrong, glide efficiently to the other place.

All I am saying is that I will set my Maxa for light air, the Perfection to move round and I still really need a heavy model. BUT - I want the weight in motor, battery and lots of carbon - Not all of us do perfect landings in bumpy air so I want survivability.

I don't think a big prop matters too much on the Maxa, but whatever the "fast" plane is, it will matter far more - RFM prop & cranked hub will be on the list.

Anthony.
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Old Oct 25, 2012, 06:08 AM
VHO
glider misguider
Armidale NSW Australia
Joined Feb 2007
564 Posts
Just to add to the mix of motor / gearbox combinations.

I use 2 motor / gearbox combinations in e-Supra-ish toys (home built std Supra wing and a wing with 3.6m span and a slightly thicker section based on the AG40 series I made up about 3 years ago - flying weight on both <1900g).

The combinations are Mega 16/20/2 with Kontronic KPG25 5.2:1 and a 16/25/2 with KPG25 4.2:1 gearbox. I use 17x9 - 17X11 props and Jeti 70A switched BEC controllers with TP 1300 3s 65c batteries.

Happy with the performance in F5J format. Can climb to 200m in 20secs if need be, but clearly better not too.

YMMV

Hutton
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Old Oct 25, 2012, 08:32 AM
Flying = Falling (Slowly)
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Tulsa, OK
Joined May 2004
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Quote:
Originally Posted by davidleitch View Post
Just to add that I am trying three different motors a Kontronik 480 + 5:1 (excellent power a bit on the heavy side), a Kontronik 400 + 5:1 and a Reisenauer gearbox on slightly hot Scorpion motor.

I've yet to test the latter two. I plan to try and keep the props relatively small. Its clearly less efficient but I don't care about efficiency any more and the small props provide a cleaner front end once you turn the power off.

I'll post some results eventually when its all installed. Have to build a new maxa first. I had a transmitter failure (a regulator blew up in the tx and it instantly died completely) causing a complete loss of model. The good news is I have the new fin so can put the servos in the tail fairly easily.

Had I known of the new 6.7 box that would have been tempting. However must say the Kontronik service has been excellent with quick delivery of the motor. Also I'm a big fan of the Kontronik ESC and the 55 amp model is a good fit.

This thread is about motors but I can't agree that the Maxa is only a light wind model. It has a low wing loading and a slightly thicker foil than the Supra but I flew it in strong winds in competition and was able to penetrate (slowly). Its excellent handling is a big help in that regard.
Sorry to hear about your Maxa. I am still enjoying mine immensely. I am preparing to build up another one to set straight the things I did not like about my original set up.

I'm going with a Neu 1107 and his new 6.7 gearbox with a Thunderpower 4S 850 battery pack and a separate 2S LiFe for the radio. I'm going with two MKS 6100's in the tail. While I appreciate the reasons for NOT having the servos in the tail, I got tired of having to fiddle to get the 1300 3S pack shoved back into the fuselage. The new setup will weigh the same +/- an ounce or so, but the flight pack will be immediately accessible under the canopy. The plane will have the oomph to launch into a 15-20 mph wind WITH BALLAST and still maintain its light weight for light air conditions.

As to the Maxa's heavy air capabilities, I think that the key is ballast. I just came back from a TD comp in Dallas where the wind blew 15-20 mph (actually the comp was eventually called due to higher winds). Large, light Aspires (carrying ballast) were hard to beat. And during the last windy round that was flown, one of the guys was flying a 4m Maxa with about 20 oz. of ballast in strong, gusty (25 mph) conditions. He was able to launch high, max in difficult air and land on the spot in complete control.

Happy Landings,

Don
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Old Oct 25, 2012, 09:48 AM
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Quote:
Originally Posted by dharban View Post
Sorry to hear about your Maxa. I am still enjoying mine immensely. I am preparing to build up another one to set straight the things I did not like about my original set up.

I'm going with a Neu 1107 and his new 6.7 gearbox with a Thunderpower 4S 850 battery pack and a separate 2S LiFe for the radio. I'm going with two MKS 6100's in the tail.

As to the Maxa's heavy air capabilities, I think that the key is ballast. I just came back from a TD comp in Dallas where the wind blew 15-20 mph (actually the comp was eventually called due to higher winds). Large, light Aspires (carrying ballast) were hard to beat. And during the last windy round that was flown, one of the guys was flying a 4m Maxa with about 20 oz. of ballast in strong, gusty (25 mph) conditions. He was able to launch high, max in difficult air and land on the spot in complete control.

Happy Landings,

Don
Don, I am (as I said earlier) using the same motor / box but the next hotter wind and a 850-3S - and same servos in tail.
The battery is right there under the hatch - far better.

I have no doubt the maxa will handle the wind with 20oz added.
BUT - with 20oz to add, 2-3oz more motor, 2-3oz more battery and the rest in carbon / glass would suit me better. I have a different landing style, here we call it rubbish.
There is a lot of very expensive (light) carbon in the Maxa (and Supras) and why not just have a stronger / cheaper structure that does not get broken as easily ?
There is no need to go mad, but 20oz is not a lot to add, so room for lead would also be good...... But to start with, something that earns its way.

If you are now on your second - Do you really want 2 of the same ?
The hard spread 3.5M with more motor and battery ?
How long before Vladimir does a heavier glass version ? (well look at the supra)

Anthony.
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Old Oct 25, 2012, 10:38 AM
"...certainty is absurd."
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Joined Jan 2007
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At the other end of the price spectrum, I am going to try the HobbyKing outrunner in the e-Supra I am building:

http://www.hobbyking.com/hobbyking/s...dProduct=14734

I have had good success with an NTM (HK) 3548 900KV motor in a 2100g glider, but the motor is a bit heavier than I want. The 3540 600KV motor is a bit lighter (146g), and the lower KV should allow a bigger prop. And for $17.59 it is about 1/15 the cost of most of the options discussed here.

While the bigger props gearbox set-ups allow might be nice, prop efficiency does not always get better at the lower rpm required. Low Re effects on the small blades at low rpm can hurt the prop efficiency. These tests by Selig et al at UIUC, while limited in rpm range and prop types, show there is definitely an rpm you don't want to go below for most props - fortunately it looks like 3000rpm+ is OK for many props.

http://www.ae.illinois.edu/m-selig/props/propDB.html

Kevin
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Old Oct 25, 2012, 10:38 AM
Flying = Falling (Slowly)
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Tulsa, OK
Joined May 2004
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Quote:
Originally Posted by esloted View Post
Don, I am (as I said earlier) using the same motor / box but the next hotter wind and a 850-3S - and same servos in tail.
The battery is right there under the hatch - far better.

I have no doubt the maxa will handle the wind with 20oz added.
BUT - with 20oz to add, 2-3oz more motor, 2-3oz more battery and the rest in carbon / glass would suit me better. I have a different landing style, here we call it rubbish.
There is a lot of very expensive (light) carbon in the Maxa (and Supras) and why not just have a stronger / cheaper structure that does not get broken as easily ?
There is no need to go mad, but 20oz is not a lot to add, so room for lead would also be good...... But to start with, something that earns its way.

If you are now on your second - Do you really want 2 of the same ?
The hard spread 3.5M with more motor and battery ?
How long before Vladimir does a heavier glass version ? (well look at the supra)

Anthony.
Attachment 5256972
My objective in going to the Maxa was to get an electric that more or less weighed the same as the TD equivalent of some very competitive TD plane. The Maxa has done that for me within an ounce or two. It appears that the trend in TD planes is to large (4M) and light (Maxa, Aspire, Explorer) and, it seems, that just as I get an electric that more or less matches its TD equivalent in weight that the TD planes are trending lighter still.

I am not, by any means, a world class pilot. I just want a plane that is fun to fly and will perform well in fair weather. I will tolerate flying in crap weather only up to a point, and then, like the honey badger, I just don't care. I am not inclined to buy a plane to use in conditions that I do not enjoy flying in. That is for younger guys who still have something to prove. The Maxa with ballast flies quite well when ballasted for wind. And it lands quite well. I am not particularly skilled at landing, but the current electric landing tasks are pretty easily accomplished with the Maxa -- which lands more easily than any other plane I have owned.

As to two nearly identical planes, I am prone to stick with one design and learn how to fly it as opposed to further complicating the learning process by changing planes. Two planes give me a back-up in case I need it. Although in this case, I will likely sell the older Maxa.

Happy Landings,

Don
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Old Nov 05, 2012, 04:11 PM
Tragic case
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Sydney Australia
Joined Feb 2002
5,875 Posts
So I found both the Kontronic 480 and the Skorpion 2221/8 with Reisenauer 5:1 to pull an initial 500 watts with a 15x8 prop on a TP 1300 3S pack. The Skorpion is maybe 30-40 watts less and given the lower mass will be a bit less efficient.

Both motors have a Kontronik 55 amp esc. I made the decision to use the BEC on the esc rather than a separate battery pack. So far performance has been flawless. The logger shows the receiver battery voltage to be rock steady 5.6 volts on both controllers in static tests. Outside of wear and tear on the battery and esc connectors, the main risk is over propping and over heating the esc at which point it will shut down.

The Kontronik setup weighs about 100 grams more than the Skorpion about half the extra weight is in the gear box. The Kontronik setup could easily handle a bigger prop.

Both motors and gearboxes have performed very well in the extremely limited testing so far completed.

The Kontronik pulls up an 1850 gram Egida quite easily, climb rate about 70 degrees
The Skorpion pulls up the Maxa which is maybe 80 grams heavier (20% more wing area) quite well. I need to put a logger in to check the climb rates. Too busy trimming so far.

With the servos in the tail and the light motor, the battery has to be all the way forward in the new maxa to get even an aft CG. After adding the ballast tube there is no more room for the logger in the Maxa than when one of the servos was mounted forward and the other midships. The model flys well as it is but I am still tempted to put the bigger motor in and move the battery back under the ballast tube.

Both the Egida and Maxa fly well in Sydney spring conditions but then so would a boat anchor. They are both fun to fly and it becomes a matter of preference.It will require hours with both of them to fully appreciate the strengths and limitations. I will say that the Maxa handles fantastically well for a 4m plane.
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Old Nov 05, 2012, 04:36 PM
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David, we are in "e-Supra motor choice."
(Pop back to your Maxa thread ? )
I would love to know about C of G and why is it heavier tham mine - Larger tail ?

Also what is Egida like, and more.

Anthony.
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Old Nov 15, 2012, 09:11 AM
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Quote:
Originally Posted by dharban View Post
My objective in going to the Maxa was to get an electric that more or less weighed the same as the TD equivalent of some very competitive TD plane. The Maxa has done that for me within an ounce or two. It appears that the trend in TD planes is to large (4M) and light (Maxa, Aspire, Explorer) and, it seems, that just as I get an electric that more or less matches its TD equivalent in weight that the TD planes are trending lighter still.

I am not, by any means, a world class pilot. I just want a plane that is fun to fly and will perform well in fair weather. I will tolerate flying in crap weather only up to a point, and then, like the honey badger, I just don't care. I am not inclined to buy a plane to use in conditions that I do not enjoy flying in. That is for younger guys who still have something to prove. The Maxa with ballast flies quite well when ballasted for wind. And it lands quite well. I am not particularly skilled at landing, but the current electric landing tasks are pretty easily accomplished with the Maxa -- which lands more easily than any other plane I have owned.

As to two nearly identical planes, I am prone to stick with one design and learn how to fly it as opposed to further complicating the learning process by changing planes. Two planes give me a back-up in case I need it. Although in this case, I will likely sell the older Maxa.

Happy Landings,

Don
Don as I have said, I have a different view of plane usage.
Before the Maxa I bought an Ava - which became obsolete when I had flown the Maxa.
The Ava was set up to fly in light wind conditions. But NOT flat calm.

It was either sell the Ava or find a good use for it - so it is now my dedicated flat air plane.
A smaller motor to get to height in 30 secs, the smallest battery that will do 2 rounds and carefully set up for no wind early morning flights.
At well under 6oz/ sq ft it is far lighter than the 7.4oz/sq ft of the Maxa.

After 2 months (not that many flights) it is finally flying how I wanted.
http://www.rcgroups.com/forums/showa...0&d=1352991030

The above air was almost flat calm, with a slight hint of breeze against my back.
The 2 peaks after 10mins was where I put the brakes on because I was going into low cloud / poor visibility. The whole of the last portion was where I added down trim to make it back to the field. You cannot believe how slow it was flying in normal trim.
This flight was only possible because it was so light / suited to the conditions. If you look at the vario reading, in the rising parts it was only doing 0.2 - 0.3m/sec.
Whilst flying I could not really see that it was going up, more that (as time passed) it was not coming down.

This is not what I was actually talking about - - 1 light and 1 heavy model.
This is more a reason to have 3 - 1 ultra light, 1 general and one heavier wind.
So, I am just trying to point out that a dedicated plane for specific conditions (in my opinion) is far better than 1 and add ballast to suit.
Hence the motor / battery / esc choice should be worked out for the conditions the plane will be used for.

Anthony
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Old Nov 15, 2012, 07:30 PM
Flying = Falling (Slowly)
dharban's Avatar
Tulsa, OK
Joined May 2004
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Quote:
Originally Posted by esloted View Post

This is not what I was actually talking about - - 1 light and 1 heavy model.
This is more a reason to have 3 - 1 ultra light, 1 general and one heavier wind.
So, I am just trying to point out that a dedicated plane for specific conditions (in my opinion) is far better than 1 and add ballast to suit.
Hence the motor / battery / esc choice should be worked out for the conditions the plane will be used for.

Anthony
As to ultralight vs. light (AVA vs. Maxa) in perfect morning no lift conditions, I considered that with TD flying but eventually never pulled the AVA out of the bag in open class comps. I would observe that the same possibility existed three or four years ago when Supras were significantly more heavily loaded than the current Maxa/Aspire genre. And guess what -- I never saw one of the really good flyers ever pull out an AVA to seek an advantage in those conditions. I suppose that there are conditions where it might be advantageous. But all the years that I have been competing I have been consistently beaten by skilled pilots who were more concerned about learning to get everything there was to get out of the plane they were flying than trying to find much of an advantage in bringing a quiver of planes to the meet. Especially for ALES, a good pilot will not likely need an ultralight to compete in very light conditions. F5J might be different -- I don't know. We'll see.

At any rate, I do this for the fun of it, not the prize money. And 90 percent of my flying is not contest flying. Just fun flying and practice. And for me, it is more useful to concentrate on learning to fly one plane really well than feeding my ADHD with too many choices. I'll take my chances that the Maxa will be adequate for everything from zero lift to the normal good flying conditions that we enjoy here.

As to a heavy plane for strong winds, I will take my lumps with a ballasted Maxa and when flying becomes simply unpleasant, I will pour a toddy and let the real men prove their virility to the rest of the world (and fight for the handsome purses that our events usually include). We do occasionally get a breezes here in Oklahoma and Texas and, frankly, I have watched several TD Maxa's compete quite nicely. Anyway, I've got a real nice travel case for my plane when the wind exceeds the limit on my fun-meter.

My competition objective is to learn to set up and fly one plane as well as I can. And I will know that I am ready for the next step when, in mama-bear conditions (not too calm and not too windy), that I can reasonably expect to beat LJ and his friends. Until then, I am not really inclined to have three planes to fly in three distinct situations -- in ALL of which I can expect to be soundly defeated by LJ.

I have nothing against the "quiver of planes" concept. But it seems more appropriate for guys other than me who have have the ability to get everything there is out of a single plane. Trust me. I am not that guy.

Happy Landings,

Don
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Old Nov 16, 2012, 02:39 AM
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No, No, Don, please read again.
The Ava was originally built for "normal" conditions - I altered it for flat calm. Which is quite a change......... Had I not done this the Ava would have been sold or just never used.
I don't have 2 Maxas, so I simply used the Ava.

All I am talking about is that if you have 2 of the same plane then make full use of them - One light and one heavy.
You are flying the same plane In your case you have 2 Maxas - You are NOT flying 2 different planes, if they are both Maxas then they will both fly like Maxas.
However, it is NOT simply a matter of adding lead - I spent 2 months getting the Ava to fly well when lighter.
If you were set up for flat calm, how can you quickly add lead and fly the plane at its best in a breeze.
Anyway, it looks like we live 4000 miles apart and our views on the sport are similar............ You prefer one plane for all conditions and I prefer ones tried and tested for various conditions....................... Enjoy !
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Old Nov 17, 2012, 09:49 AM
WINS - Winch In Nose Sailplane
jaizon's Avatar
USA, NH
Joined Mar 2008
3,109 Posts
Gentlemen,

this thread was started as a "e-Supra motor choice for ALES" thread but has gone pretty far off course. I suggest that those interested the other valuable topics that have come up as of late - start a new thread. Thanks.

Preston (the thread starter)
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