FWIW I've just negotiated a deal with a guy to buy his nearly RTF Wind 110 S. It supposedly was the demo model flown at this year's SEFF and Joe Nall events. If all goes well, I should have it in about a week.
I'm looking very forward to getting it up in the air.

According the the guy I'm buying it from it flies really well on 9S. It has a Hacker A50-16L in the nose. I just happen to have some 4S and 5S 5000 packs so this will be a fun combination to try.

I take it the 9s is a typo. The A50-16L works best on 8s, otherwise you'd need a smaller prop which gets turned at a higher RPM; not really what you want.

9S is not a typo.... That's what he told me. He said "I know this is an 8S motor but......" I'm certain he knows what he talking about. He had 3 Sebart demo planes he was selling. FWIW, you don't have to swing a smaller prop just because you increased one cell. You just have to be sure you aren't over taxing your gear, as in pulling too many amps. I'll clarify things with him before I give it a try.

The A50-16L swings an 18x10 as about its max. The temperature of the engine is it's limit. If you go to 9s, you will have to lower the load to keep the temperature down. So you'll have to mount a smaller prop.

Tell you what... I'll give it a try with whatever prop he says and I'll report back my findings. My guess is that in the end, I will not like the outrunner at all and will switch it out for the C50 10XL that I have. I fly a 9 lb Yak with that motor on 8S with an APC 18x12 and it's wonderful. I imagine it will be great on this plane too. Still, I'm going to try the stock set up first before I go off making any changes. Who knows, maybe my flying preferences are simular to the designers.

Stock setup is the A50-16L on 8s

Anyways.. I'm curious what your results are. If you don't like it at 9s, then try it at 8s with the proper prop

How guys here manage to put 18x10 props on their Scorpions (250kv) on 10S and not blow them up, It's crazy amps as far I saw playing with motocalc.

pics of the opened cooling holes; it is best to draw the shape with a sharpie, then cut the line with a blade. the paint will chip but not chip past the line. rat tail files, and small wooden sticks with sandpaper CA'd to the ends for different shapes and good workability.

Go to Scorpions website and use their calculator. The numbers on their calc program are extremely close to the numbers I get with my meter, and with my data logger. Roughly 75A with the 18x10e on 10S.

75A on 10S is overkill and probably you're overheating your engine then. Say 37v * 75A = 2775 Watt absobed power. I can hardly imagine it also outputs 2775 Watts of engine power, considering I'm flying it with the A50 on 8s with about 2.1kW max, and that is sufficient. With 2.7 actual kW of drive power, it would be wildly overpowered.

Probably your prop is too heavy, causing the engine to heat up and not work efficiently.. which would also explane why the engines break down in flight.

I would either go to 8s to maintain prop size, or mount a smaller prop to get the power down.

One has to understand there's no such thing as a 'so-and-so-much-Watt' engine, or a 'so-and-so-much-cells' engine. The only thing that counts, is engine temperature. If your engine stays cold, you can mount a heavier prop, if it gets too hot, you should mount a smaller prop. You could run the Hacker A50 on 20s if you wanted to, but then you would probably have to mount a very small prop.

What happens if you mount a too heavy prop is not that you get more actual engine power. The consumed power will go up, but this wont translate into drive power but into heat. On any ordinary engine this will cause the magnets to demagnetise (most of the used magnets do that around 85 degrees celcius), which will also cause the current to go skyhigh.

However, scorpion is the only manufacturer that uses a different kind of magnets, which can withstand much higher temperatures, I believe even up to 200 degrees celcius.

So my theory is that some of you have too heavy props on your scorpion. Since the magnets can handle the temperature, the engine will work and it won't start using absurd amounts of power, however, most glues used in engines can't stand those temperatures so if you overdo it, the engine will still come apart.

75A on 10S is more than most 2m flyers use, so something is wrong. I suspect that with a one or two size smaller prop, your current will go down more than you'd expect, the engine will stay cooler and you'll still have roughly the same amount of propulsion.

Hezik, I saw somewhere, that you got 8000 rpm out of hacker on 18x10 on 8S, how is that possible, if KV is 270x 30= 8100, in motorcalc- to spin that prop to those rpm you have to use 10s and 2,5 kw.. or that was in flight data?
I'm just sitting and calculating, and collecting as much data as possible for 8s motors because I will definitely swap turnigy to something better in a while.

How do you think, will a scorpion 4035-330 would be good on 18x10 type of load? 250 seems too underpowered at 1300+ watts on 18x10. I'm just curious of all options, because i would like to be able to fly F11 in all conditions without bothering about power or braking capacity.
Or I think too much ?

That was in-flight data.. I don't own any scorpion engine, so I can't tell you how it will perform. All I can do is theorise when I hear data and see people having problems. What I do know about Scorpion, is that their engines seem overspecced compared to competitors. Also I have seen an heared several people having the same problem; being components falling off the engine in flight, in particular, the magnet-spacing ring. If I put those two together, I get the impression that those engines are stressed too hard and therefor fail.

If that's true or not.. in my view it is likely at the least, but it's a theory, not fact.

As far as I have seen, the Turnigy is one of the best engines you can buy for the WindS 110, as in, it's the best match. Only downside to any turnigy item, is that their quality control lacks in respect to other manufacturers, and there's a reasonably big chance you'll get a fluke (again: compared to other manufacturers).

If I had unlimited budget and was told to buy the best engine I could think off, I would probably buy the C50 inrunner that Sebart specifies as the competition setup.

In reality I would never do that, since I don't want any kind of gearbox on my engine.

Thanks for your response Hezik, I neither would like a gearbox, since I fly really much, and I will have to send gearbox to USA or somewhere else, to get parts replaced every 50? flights, as we here have no Hacker service centers, so I'm mostly on outrunners. I am in fear of turnigy, that even after regluing magnets and tightening all that is necessary- it can always fail because of something else, that's why I already start looking for new engine and collecting funds for it, as I will use turnigy for 2 competitions, that I have in beginning of august.
So basically there are three options for this bird
Turnigy 5065-270
Scorpion 40xx /250/330
Hacker A50-16L
Or there are more options?

garcfield thanks for the photos!</p>


</p>

What hezik wrote, the only thing that really matters is the motor temperature. One thing that also should not be forgotten is that all lab measurements are done at  25C degrees, so if you fly at  35C degrees and you are already on the limit with your prop that should be taken into consideration.</p>

Have you tried 9S yourself or are you just making a guess based on what you have flown? My plans are to try 8S first and see how it flies. My next plan is to try the sellers recommendation of 9S and whatever prop he says he used. If I'm still not happy then I'm going to pull the outrunner and mount my C50. I used the C50 in a Dream 110 on 8S with an APC 18x12 and it was fantastic!

Hi guys............just an update.

I finally found my Wind S110 in the jungle. It was up a tree about 30 feet high but I managed to shake it out . As I suspected the airframe is totalled but I do have all the electronics with the exception of the ESC. There was a wide debris field and the left side of the forward fuselage was missing and I suspect it was thrown into another tree and hung up. After two hours of intensive searching for it it could not find it. My buddy couldn't make it so my wife came out to help.......what a trooper!! She was a great help as she stood at the edge of the field as I went into the bush and I would yell and she would say if I was right or left of the line. It's impossible to stay on the line while travelling through the dense underbrush. Turns out I was dead on with the line I took but the wreck was further in the bush than I thought. The motor looks fine but until I get another ESC I will not know for sure. All the rest of it looks good electronics wise and I even have the flight pack battery which I will test out shortly. I had fully charged it before the days flying and this was the 7th flight of the day when it went in. i was putting 35-40 mAh back in the battery for each flight so it should have only been about 300 mAh out of an 800mAh pack. All I know is the radio just went completely dead.

There is some good news. I will be ordering a new one tomorrow and hopefully be able to pick it up in Blaine, Washington in about a week. I will fly my Vanquish in Intermediate next weekend at Chilliwack, BC and hopefully be able to take enough tools to build my Wind on the road in the back of my travel trailer in time for a contest in Edmonton, Alberta the following weekend.

To all who offered sympathy and support and especially Mike C I would like to thank very, very much. This really is a great forum and the people involved are second to none imho.

Thanks again

Murray Johnson

These are other options:

Neu 1900 series (direct-drive inrunner, no gear box)
Hyperion 4035 series, or 4025 series (heavy)

The C50 setup will work very well, but I think you'll be happy with the A50-16L on 8s.

To answer your question; I have not flown it on 9s. However, it's not a guess either. I have been flying the WindS 110 for about 1 year and 3~4 months now, and have made roughly 1050 flights with it in that period, trying different props. Last contest I came in third in the top class here in the Netherlands.

The 18x12 prop is too big a load for the A50-16L in warm weather conditions, even 18x10 is on the heavy side then. With an outside temperature of 25 degrees celcius, your engine will be about 65~70 degrees celcius when you land, measured on the outside. The magnets start to demagnetise at about 85 degrees celcius, so it's all pretty close to the limit of the engine.

With 1 cell more, it will try to run 270 RPM more, thus the load will even be heavier. It's a simple fact that if you have the maximum propsize for an engine at a certain number of cells, that you will have to chose a smaller prop when adding cells.

Anyways, whichever option you chose, I'm sure it'll fly and you'll have lots of fun with it. It's a fine airplane and both setups should have sufficient power. The C50 setup would probably be the best choice.

Sorry to hear the loss. It is even bad that it happened before competition.

For the 800mah flight pack, the worse case is 35mah * 6 = 210 mah putting back. Depending on how many have been drawn during the 6 flights, putting 35-40mah back per flight may not be sufficient. I use 1100mah pack on my Venus II and do a full charge after every 4-5 flights.

Receiver, switch or regulator (if any) could also be the cause.

I understand, you have a lot of experience with this particular plane and power system setup. I'm not as concerned about down line breaking as you seem to be, so maybe a 17x10 on 9S will suit my fancy. I have all sorts of props in this particular range, so I can experiment.

If the motor has a Kv of 270 and I increase one Lipo cell it will not try to spin the prop a mere 270 rpm quicker. That would happen if I increased the voltage one volt. In this case Lipos are approximately 3.7 volts per cell meaning it will try to spin it nearly 1000 rpm quicker. That could be a killer for the motor. I don't know. What I do know is that I've been able to push my Hacker gear fairly hard without suffering any damage. Of course, there is always the first time. [X(]

MJ,
You may want to replace the batt, switch, extensions and reg at a minimum.
At least you have all the settings and knowledge for the plane. I bet you get it together in less than 10 hrs!
Good luck with your back to back contests. Hope to see you in Hollister.

Every 70 flights it is about half an hour of work that is done by yourself. No big deal.
http://morten.laugesen.nu/HackerC50.pdf

Everbody has a different 'taste' so by all means experiment, what I find perfect might not suit your style

It's not just the downline breaking, it's also the amount of 'pull' the engine has without developing too much speed in straight lines.

Offcourse you are correct in this, I took too little time to think about it

Woow, thanks, I thought, that planetary gears must be completely changed to new ones every 50-70 flights. Thanks for info!
How long do gears last in these motors, if you recheck, and grease them in let's say 50 flights? A lifetime?
I must start to make choices, and order an engine on beginning of august.

Hi Guys...........just an update on my Wind crash.

The plot thickens. I just looked at my flight pack and it was showing 71% capacity and 3.97 &amp; 3.96 V on the cells. I charged it to my usual 95% and I only put in 175 ma. I then cycled it just to make sure and it is normal. There are now two possibilities for the complete radio link loss. The malfunction occured right after my snap on the 45 degree downline and after the recovery it was completely dead and very precisely coninued on the 45 line right into the bush. One of the possibilities would be a flight pack battery disconnect from the system. The other would be a complete loss of data link to the receiver (blackout?). I always run my JR9303 with the antennea vertically. Would this cause a loss of signal?? Should I be running with the antennea at 45 degrees instead?? This is my first problem with 2.4 ghz that I have come up against and has me baffled and POed. I thoroughly tested all the radio equipement and all is normal. I am going to use another receiver in my new one so hopefully I will not have the same problem. Any