FallingWithStyle

Looking for a precision aerobatic plane in the 10-12oz neighborhood (before battery). It has to maintain ZERO surface warp under pattern aerobatics speeds, so depron and other foam material is probably unacceptable unless you know otherwise firsthand. Oh, it'd be nice if it can do some 3d like harriers too. And strong enough to handle snaps, spins, and blenders.

Only one I've found so far is Stevensaero G300. Looks like what I want, but its over a year old and I see little forum activity on it so I'm somewhat skeptical. Anyone have this one?

Any other options out there?

Thanks
Clark

aflipz

My Feedback: (10)

I'm looking for the same thing... Light on it's wings, stiff, fast and 3d. So far i have never seen this in a park sized planes.

foam is very light. My gws formosa (1) comes in under 15oz all up with landing gear. It's pretty stiff too, but it won't 3d at all.

I had a u can do 3d ep from great planes. It was very very light on it's wings, stiff as spongebob squarepants, 3d's allmost too easily but won't pattern even if it's life depends on it.

So far i'd say the u can do was the most fun plane i have had, it's so stress free, and in a way it's like flying a very aerobatic kite. It will take a million repairs and fly good as new, light stiffenning techniques improve it's flight characteristics in larger aerobatic maneuvers. But it's sluggish in the air, so much so that i lost it in 20mph winds when suddenly stronger gusts carried my plane helplessly out of range in the city, wot into the wind, but flying backwards it went. I will try one of their yak55 flight flex next but i'm not expecting any speed, just a ton of fun in small spaces. Someday maybe we'll find the perfect all around plane but for now, i'll be modding my formosa to see if i can make it obey like i want it to. If not it gets recycled... and back to the hobby shop.

Someone?

FallingWithStyle

I don't want to be unrealistic. 3D is helped by fat wide wings, so anything that can fly faster precision is going to comprimise that. But anything with a t/w near 1.5 has some potential for 3d...

So tell me more about the Formosa. You say its plenty stiff? How strong is the stock power plant?

Clark

aflipz

My Feedback: (10)

never tried the stock power plant.

Bear with me on the technical stuff, i'm a novice flyer. Have had only 3 planes and tried a couple of others on trainer and have started flying somewhere in june of this year, but i have had massive stick time in that period.

My formosa only has about 1 hour of flying on it, it flies straight as an arrow if you want it to, i built it light so it glides; this plane is available as a slope glider according to the manual. In level flight i can go on and on forever without throttle. It has a tendancy to tip stall when too much elevator is applied, maybe not as bad as a warbird but it's something to look out for compared to a 3d plane. It handles wind pretty well, I have harrier'd it and even hung it off the prop BUT the ailerons stop about 2-2.5 inches from the fuselage on each side, that section of wing is fixed therefore all the thrust from the prop goes right by without providing the "vectored thrust" that you would get from a large full control surface. Result; when you are hanging on prop you can push the ailerons in either direction all day and it won't do squat. So you can only keep it vertical using the somewhat limited rudder and elevator and are powerless to roll one side or another unless you climb fast. Also, when doing harriers the airspeed is very low, and since airspeed is the only thing that allows aileron effect then harriers have a ultra low roll rate.

The good; with a good brushless setup it will go pretty fast, mine was weak but it still climbed vertically from a hover, at the time it was 16oz, tp2100mah, electrifly rimfire 1000kv outrunner, 9x3.8 prop phoenix 10 esc. I should have used a 25 amp esc and a slightly more agressive prop, it was too close to the limit of the esc. I was having more fun with the u can do 3d than my formosa because of the ailerons so i took all the flight gear out and mounted them back into the other plane. Since then i haven't flown it but i have been busy... I cut out the fixed part of the aileron and epoxy'd it to the moving part to increase surface and more importantly to have a part of it in the thrust. I replaced the 1000kv motor with a bp21 outrunner and a 8X4 apc prop, have a cc25 esc and will use tp pro lite 1320's 11.1 to power up. Should be under 15 oz. No idea how the aileron mod will perform, i should know within a week or so. It could kill the plane or it could breathe life into it, it was a chance i was willing to take.


the formosa II is out now. It has full aileron, similar shape as mine, and the rudder and elevater are bigger plus have that part that extends all the way to the leading edge of the stab and elevator, to unload the servos and increase surface. Now this must be interesting because the formosa is a good plane, this 2nd gen has been in the works for a long time so it has to be worth their effort, plus the formosa 1 is still selling like hotcakes.


According to many, and my own experience molded foam aircraft are just as stiff as balsa models but lighter and when broken they glue right back together. The main disadvantage is that the choice of models is limited, and models that come out tend to hold their ground forever before being replaced. Must have something to do with the fact that it's so time and $ intensive to design, prototype, test a model then make the molds for production that once it's done they have to sell huge volume to make up for the expenses. So while balsa and wood planes go from paper to production much less time and with simple tools we keep seeing new generation lighter more "in vogue" covered planes like new 3d models keep popping up from a lot of small companies, sometimes home businesses. Flat foam is even more widespread, those can be made out of deperon by kindergarten classes and it seems like everybody and his uncle has a flat plane company.

I am enthusiastic about the future of molded foam planes. they will get better and better and i feel it's the dawn of a new era of superior all around performance and light weight.


p.s. i just got an email from "air support" at ultrafly rc. concerning their extra 300s aerobat. I asked why their foam model was so pig heavy at 22oz, He said "all i can tell you is it's flying weight is between 7.5 to 9.0 ounces" Wich sounds way off... Their video does look very interesting. Still 9.0 oz auw seems unreallistic, he must mean 7.5 to 9.0 oz/sq foot wing loading. 7.5 is not bad at all. And it's absolutely stunning to look at.

http://www.modelflight.com.au/ultraf..._extra_300.htm



p.s. yes a fatter wing will slow a plane down, plain aerodynamics. But there must be a way to slim it down, retain the wing area increasing speed while keeping low speed flight possible (at higher alpha)

twinturbostang

So here are two that seem to fit the parameters...

Ultrafly Extra 300S:
http://www.ultraflymodel.com/airplanes/ufla1060.html

EFM Sabre:
http://www.3dhobbyshop.com/detail.aspx?ID=451&src=hsi


Decisions, decisions... BTW, the weight on the Extra does seem a bit suspicious. Same wing span and length. Both made of foam (although different types I think). Sabre has more wing area too (275 vs. 218 sq. in.). That could be a plus for the Sabre though.

aflipz

My Feedback: (10)

totally a plus for the sabre. the extra's numbers are all off and it's wings are thicker. I'll let the forum give the truth in time... Looks better but that's about it, i'm putting my money on the sabre.

a word of warning, the saber does appear to have airfoil wings but they are razor sharp... (why else would they bother molding depron) It should be a real handfull going from a estarter. Then again, these can be repaired, and if youre not flying outside your abilities you aren't learning anything, right? And i'm sure you want to be a better pilot as much as i do.

Commence project Sabre!

twinturbostang

So which would you recommend for me then?

I went back and re-read some info in the U Can Do thread, and it sounds like the Extra may not work. Check out post # 253 by TManiaci here: http://www.rcuniverse.com/forum/m_26...11/key_/tm.htm
The high weight had me concerned a bit. Was looking for something around 15 ounce-ish. I guess that was first indication that this may be a big too big for a "park" flyer.

BobbyGee

My Feedback: (3)

Clark,

Have you taken a look at the Mountain Models Flashback? Good pattern plane, don't know about the 3D.

There's a review of it by Martin Hunter here:

http://www.smoothair.ca/content/view/70/43/

Hope this helps.

Cheers!!!

BobbyG

PS - we hope we're about 2 weeks away from starting flying at our new club field. Have you been following progress on the club's website?

twinturbostang

I'm going to contradict myself now... This sure looks like a great park flyer to me:

http://www.ultraflymodel.com/movies/...00-1-large.mpg
http://www.ultraflymodel.com/movies/...00-2-large.mpg

Looks like a good review here also:

http://www.rcgroups.com/links/index....72&skey=e2662c

I'm thinking about going with the Extra afterall, and see what happens. Maybe we can get our planes built and then compare notes. I'm going to need help on a motor/battery/prop combo though. Any suggestions? I saw some people using the Dymond motor combos and at ~$50 for some of them (like the Cool S 4200), they looked like great deals: http://www.rc-dymond.com/order_motor_brushless.htm

aflipz

My Feedback: (10)

go for an outrunner, delete the gearbox. Keeping the number of moving parts to a minimum is the secret to reliability. 4200kv is a good hot motor, but you can get same or better performance with a lower kv direct drive outrunners without the gearbox headeache. The thing is a outrunner is pretty much meant for a very specific use, usually with 2-3 ideal choices of cell count and prop combinations per motor. While geared brushless are way more flexible because they can use different gear ratios to spin larger or smaller props at various rpm's according to the needs of a model in particular. Ex; gear 3:1 for a very small fast spinning prop for a pylon racer, then take the same motor, put it in a 8:1 gearbox and use a giant 3d slowfly prop that gives high thrust with low rpm... For such a big difference you'd need to use 2 very different outrunners. But believe me it's well worth it never to mess with gearboxes. Inrunner brushless motors are more efficient by themselves, but once you gear them it more than offsets the average extra 10% efficiency that they had in the first place due to gearbox drag.

T-man seemed to find it's wing loading very high i remember discussing that with him, but i never asked what his setup was, did he have nicads or lipo's brushless, brushed 400, cobalt motor? who knows... 2 identical planes with different setups will fly like 2 entirely different models. The one in ultrafly's video sure doesn't fly like a 22oz pig... and i don't think the landings will be hot at all seeing how it slows down to do those inverted low and slow passes.

still i'm going to the lighter dual purpose plane, i'll definitely post here when i have data to share. I'm going to go to ridiculous lengths to make is as light as possible, as far as cutting all excess servo wires, de-casing rx etc...

check out the scorpio loop 3d by hobby lobby, very very light, but again looks slow due to the thick airfoil.

edit; on rc dymond, for a 10-15oz plane i'd go with the maxi 16 and a 25A esc. I'm not sure what the exact result would be but i have a feeling it would be overkill on something in the 15oz range. especially with a 3 cell lipo and 10x4.7 prop For the record i'll use something much smaller in the saber, to keep weight down and flights long.

twinturbostang

Well, I went with the Ultrafly Extra. I ended up getting the one that came with the A/30/29 motor and gearbox. From the review linked above, it sounded like it was a good combo for it. So I'll see how it does. I may try a couple different packs on it also, to see what kind of weight/flight time compromise I'm dealing with. Probably will use a 3S 1320 (or 1500) and a 2000. In the future, I may go with an outrunner. But for now, while I'm still learning all this stuff, I think it's better if I have more combinations to choose from (eg: gear ratios and prop combos). Just need to pick up a battery and ESC now, and I'm good to go.

Question: I forgot to order servos with the plane and other stuff. Is the Futaba S3108 a good servo to use for this application? 7.6 grams and 17 oz-in of torque. I can get them at a reduced price in quantity from Tower...
http://www2.towerhobbies.com/cgi-bin...?&I=LXFKZ9&P=0

aflipz

My Feedback: (10)

3108 should be fine

twinturbostang

Thanks. Just need to decide on esc and battery now. Was thinking of going with the Cool Running 25A: http://www.coolesc.com/prod_a25.php?CC=4317692caa80f
And the Dymond 3S 1500 or 3S 2100 lipos:
http://www.rc-dymond.com/order_batteries_lipol.htm
Any suggestion on which battery would be better? Obviously it's going to be a weight vs. flight time trade-off.

aflipz

My Feedback: (10)

If i were you i'd go for the thunder power 1320 pro lite batteries. the dymond stuff is made in china, low discharge and just plain heavy compared to the amps they can provide. For example, a tp1320 pl will give you 17a continuous, 27a bursts, weigh 85 grams. This is more available amps and a lot less weight at a very small penalty on capacity. I really think it's worth it. To get even close to that kind of performance you have to bump up to a 2000mah with the cheap stuff. So while the 1320 can serve a purpose in even smaller planes than your extra in the future, it will be more than enough in your extra, look for static wot amp draw under 17 amps and it's all good. Also, if i were to need a bigger, stronger pack i'd rather parallel 2 3s 1320 packs than use a 2000. Explanation; if you use 2 1320 packs in parallel that comes in at about 170 grams, gives 34 amps cont, 54 amps bursts and 2640mah. while a cheap 2000mah will most likely have problems giving you 20 amps continuous while weighing under an ounce less than the 2s1p

Another thing worth spending a few extra dollars on is the esc. People have had good experiences with the dymond stuff, but i'm sure if you cut one open and put it next to a castle creations you'll see a major difference in quality. Not to mention the enhanced programming features of the cc and it's usb programability and sofware updates; a solid investment. Believe me, i lost a plane to a faulty esc of shady origins (electrifly bl-8) the phoenix series is a "buy it once" provided you choose the right one for your application.

servos; 3108 will do just dandy, i prefer hs55's, no idea why, maybe because they are clear blue, or the fact that they are 2-3$ cheaper at my lhs...

twinturbostang

Correct me if I'm wrong, but I think the 1320 is good for 10-12C, which means 13 to 15.8 continuous.

Dymond has a 12C 1350 3S for $40. It weighs 97 grams which is not too much more than the TP. But yeah, I don't know what the quality is. The TP is at least $10 more but I guess that's not too terribly bad.

The ESC I was looking at was not from Dymond, but Cool Running, which I believe is a quality speed control, and is made in the USA... http://www.coolesc.com/ It is programmable too, and I much prefer being able to program right from the esc, instead of having to buy the usb cable and software also and connecting it to my computer. These can be programmed on the fly at the field.

Servos are on the way, as is the plane, motor, receiver, etc.

aflipz

My Feedback: (10)

You are wrong so i will correct you! The thunder power pro lite specs as per packaging and website are: 13c cont /20C bursts (17 amps continuous, 27 amps burst) everybody assumes 10c... That's the beauty of these packs; their small size and weight combined with their "big pack" power.

Programming with the transmitter is the "deffault" way of programming the castle creations, the usb mostly makes it fast and easy to make changes, and it can also be used to flash the firmware version of most cc esc's for future improvements; what's not to like? it doesn't prevent you from field programming, in fact it has a quick reference guide to carry in your flight box to help with manual programming changes at the field. It has 7 different programmable features accessible without usb. I think more are available or more precision is offered when programmed with the usb... Still 7 features is enough for me and the usb is definitely not a necessity.

1)cutoff voltage (auto, 4v 5v 6v 9v 12v)
2)current limiting (1 through 5, from sensitive to off)
3)brake type/on off (5 settings)
4)throttle type (4 settings, governer modes)
5)electronic timing advance (3 levels)
6)cutoff type (hard or soft)
7)soft start (3 settings, soft to fast)

best of all; Made in the U.S.A. (Ok, so i am Canadian, so what!) (ok, so i just noticed the cool runnings is also made in usa)

but there is one thing i prefer above all on the cc25, it has auto lipo AND fixed programming. Auto lipo checks voltage when a pack is connected and the esc sets lvc accodringly (in the case of the cool runnings this is adjustable from 2.4v/cell to 3.0v per cell but allways automatic cell detect) If you take a 50% discharged pack it's voltage will be detected as 2 cell and cutoff will be from 4.8 to 6v = a dead 3 cell pack. In other words, you can only rely on the auto lipo lvc when you connect a fresh pack, if you come in for landing with power left and want to go back up a few minutes later your lvc will be set too low, when you need it most. the cc allows you to set a fixed lvc point (i.e. 9v for 3 cells) and you can continue interrupted flying with a battery in any state of charge without worrying about cell damage.

twinturbostang

Ok, ya got me there. Sounds like the TP packs are maybe the best out there then. So who has the best deal on them? I recall seeing a few adds here on RCU for various places, but can't remember which one had a good deal. I remember seeing a 1320 under $50 and I think it was free shipping also.

Well, the price. The Cool Running 25A goes for $50, versus $65 for the CC.

Not sure I understand. Wouldn't a 3S at 50% be somewhere around 9-10Volts? I've seen voltage curves for various packs, but I can't remember what they taper off at. I don't see how that could be mistaken for a 7.4V 2S.

aflipz

My Feedback: (10)

You seem to understand the principle. the lvc checks initial voltage and if it falls within a certain range it is assumed to be a given cell count, the range isn't that broad and a partially discharged cell can easily be mistaken for a pack one cell lower than it really is. Most manufacturers of such products warn of this possibility.

the cc's switching rate is higher on the cc 11khz vs 8khz you also save 6 grams and get a surge current of 40 amps with the cc vs 35 amps with the cool running, but that's just trivial...

And this sells it alone; it makes original pac man like sounds when you power it up and enter programming mode! Sweeeet lol

on a serious note... I ordered the sabre today. 20.50usd shipping to canada, ouch (internationnal express post) ems, should be here next week though. I'll start a new thread on it, if no one does it first.

i will at first fly with my bp21 motor but i want something sub 30 gram to shed an extra ounce, also i want to spin a bigger prop slowly to 3d, not a high reving small prop. My bp21 will turn it into a rocket but it won't be as easy to hover with this setup.

twinturbostang

I did some searching, and found some interesting information. Go here and you can see a voltage curve of a lipo during discharge: http://www.modelflight.com.au/dualsky_xpower.htm
Looks like the ones tested maintained at least 3.1V until the pack was close to discharged. For a 3S, that would put the voltage at about 9.3V. An automatic detect circuit should still detect that as a 3S I would think. Also, see below a Kokam discharge graph I found in another section of RCU.

But in any case, I plan on contacting Cool Running to ask them questions about this also. You've raised a good point, and I want to be sure their circuitry will correctly detect the cell count on a partially charged pack.

Brian

aflipz

My Feedback: (10)

it shouldn't differ too much from this;

http://www.aurorra.co.uk/reference/AVC1AIR.pdf

twinturbostang

That appears to mix the lipos in with NiCD/NiMH's when auto detecting though. In that case, I think you're right. You may have a problem, because now you have many different (but small "band" ) voltage ranges to check for. But the Cool Running has a selectable switch (via Tx programming), that selects either Lipo OR NiCD/NiMH. So that probably improves things quite a bit. I sent them an e-mail though. We'll see what kind of response I get from them. I'm interested to hear what they say about their auto detect.

aflipz

My Feedback: (10)

Cool, you could start a thread under electronics with your findings, others may want to know. Are you any closer to getting your extra 300?

twinturbostang

I'll try to do that once I get a response from Cool Running.

Extra has shipped out from Tower's NV warehouse. I won't get it until friday of next week though, since it's going UPS ground (NV to MD). And will take me a week to build at least I'm sure due to other stuff that always takes up my free time. Oh well. I need more practice with the e-starter anyways.

twinturbostang

Well, I got my Extra 300S. Here's the build thread on it: http://www.rcuniverse.com/forum/m_3346729/tm.htm

FallingWithStyle

Finally read up on the Sabre. That looks like a real contender and is designed to take my AXI 2208/34 and TP 1320's. I currently have a flat depron plane and I'm disappointed with its flexing. I wonder if "molded" depron is better in that regard...

Clark