Balsa Product's Sukhoi SU-27 Flanker by Walkera

[Ejet42]

Balsa Product's Sukhoi SU-27 Flanker by Walkera Does anyone have any experience with this particular foam model? It is a sharp looking twin ducted unit that comes with 2 speed 400s; pretty decent wingspan (~42"). Balsa Products (www.balsapr.com (http://www.balsapr.com/)) seems to be a really good company - but I can't find anything about the quality of this kit nor its airworthiness. I purchased a "toy" SU-27 from one of the E-bay companies, a twin electric pusher, and it was absolutely worthless! The nose broke off on the first flight attempt. I know that Ultrafly has a speed 400 pusher prop entry complete with video of it flying (24" span) that looks pretty good. The 42" and twin ducted fan novelty is really appealing, though. Does anyone have any info on the Walkera entry? I would really appreciate hearing about it, or even better, finding a video...

[afineman]

Here you Go

http://www.rcgroups.com/forums/showthread.php?t=443769

I hope you enjoy :D


OOHH I think this is my first post


Brent

[Ejet42]

afineman (Brent),
Thanks so much for the url. That is exactly the info that I needed - I'll probably go with the Walkera Brushless 3200 Kv motors initially. The video doesn't look real fast, and I'm not sure if this plane has enough umpfff to do a loop with speed 400 brushed.

I plan to use 11.1v LiPo batteries. With one motor pulling 22A, is there an enexpensive 50A Brushless ESC with an adjustable voltage cutoff, or do I need to go to Castle Creations and pay the big bucks? Definitely want to protect that $$$ battery.

Thanks again for the reply.
H2 http://www.wattflyer.com/forums/images/icons/icon10.gif

[ParkJetsFlyer]

You will need to use 2 ESC's with brushless motors. You can try the new Castle Creations Thunderbird 18 A controllers. Dynamo Electrics sells them http://www.dynamoelectrics.com/detail.aspx?ID=945

[afineman]

ejet42

With the brushless mod I did, not only does it draw LOTS of power, but most of that draw was a waste.

Do a water breakin of the brushed motors and try them, because the plane flys SLOW the brushed motors may do fine.

Most of the flight time was spent on 1/3 power, so I would assume brushed motors will work just as well.

Also by going brushed you will only need 1 ESC (ParkJetsFlyer is correct, you would need 1 ESC per brushless motor), but the batteries Walkera sells to run these brushed motors are 9.6 volts SSOO a 2 cell may be to little and a 3 cell may be too much, but only testing would give you the final answer.

Best of LUCK

Brent

[Ejet42]

ParkJetsFlyer,
Thanks so much for the reply - I was certainly headed down the wrong path, because I was going to get one 55A (or so) brushless ESC and parallel both motors. Why can't you do that? Does the electronics "sense" the motor speed somehow and adjust the 3 phase output accordingly. I absolutely take your word for it and thank you for helping keep me out of trouble (I certainly get into enough and can use the help), but I am curious.

Afineman,
You continue to be helpful - do you think that the absence of "power" appreciation for the plane is because of the internal ducting, whereby the inlet air is too restricted by the long, narrow intake channels? I haven't seen it yet, but according to the pictures in the "online hop-up manual" (or whatever they call it), appears to be somewhat narrow and long. I am rethinking the Brushless route - after all, the 400s are supplied with the kit. I was also thinking of "retiming" them as I do have the tool. In your experience, does this plane have enough power to do a decent loop from level flight (even at full power)?

Thanks so much to both of you for your responses. I look forward to any additional info or opinions you wish to share.

H2 :cool:

[afineman]

ejet42

Because of my set up I have MUCH more thrust than I need, and I am working on converting that thrust to speed.

It is for that reason I suggested you fly it stock. We don't know ( if so no one has posted) how to increase the speed. So take this time to JUST fly the plane.

I have done many mods over the week, all these mods will be tested this weekend, and will be reported on.

Hope it helps


Brent

[Ejet42]

Thanks, Brent,
I am torn between the Ultrafly SU and the Walkera. There is a video of the Ultrafly in that thread toward the end - I can't get it to open tonight, but last night it seems that it did - or at least I found one somewhere that did. Man, what a screamer! It has a flying stab elevator and using a 6x4 direct drive pusher on a Mega 16-15-4, does 80! Actually the high speed is a little daunting for me - I'm leaning toward the Walkera because of your exprience and thread. Keep the thread unrolling - you're a good writer and documentor.

Tks again,
H2

[ParkJetsFlyer]

ParkJetsFlyer,
Thanks so much for the reply - I was certainly headed down the wrong path, because I was going to get one 55A (or so) brushless ESC and parallel both motors. Why can't you do that? Does the electronics "sense" the motor speed somehow and adjust the 3 phase output accordingly. I absolutely take your word for it and thank you for helping keep me out of trouble (I certainly get into enough and can use the help), but I am curious.

Generally you cannot run 2 brushless motors on one ESC, however some people have done it in the past. The standard rule is that you need 1 ESC per brushless motor though. I don't know all the technical stuff, but the main trouble you have using a One ESC. 2 motor combo, is that one motor may start and one my not, or one motor may run in reverse.

Using two ESC's you need a Y-connector to connect the throttle wires to the Receiver, but you use only 1 of the BEC power wires to power the receiver and servo's, using 2 wires sends double the current, and will probably burn up the receiver.

Hope that helps

[Ejet42]

Thanks, Tom! I appreciate all of the good info. By the way, that is a really cool logo you have for ParkJetsFlyer.

Henry H. (H2)

[ParkJetsFlyer]

Thanks !!!

[easytiger]

Has anybody flown the Walkera Stealth?

[Ejet42]

I wasn't aware there was one - where did you see it?

[easytiger]

I saw it on the walkera website...there is a guy called awd hobbies(?) who imported a few of them...looks nice...

[afineman]

Evening

I was able to upload the movie to Putfile ( finally )

here it is http://media.putfile.com/12-10-0589

I made some modifications that were suggested to me ( cover all the cheater holes, get ESC out of the input duct, and reduce the output to 2 1/8th inch).

Well the radar caught it at 48 Mph and the video ( via sound ) caught 49 Mph ( on the 2nd to last fly by) and I was only at 3/4th power, so it was a big improvement.

Next time up will bring a variety of exit cones ( 1 7/8 to 2 1/4) and will try to record the results.

Enjoy


Brent

[Ejet42]

Brent,
Thanks for the persistence - it looks like you are honing this to a fine edge. The SU looks stable and appears to have plenty of power, if not the absolute speed you want. I think you mentioned that you had two 2200 mAh 3S LiPos powering the fans with brushless motors - how much flight time do you get with normal throttle management? The question stands, but I just scanned the "other" string and didn't spot it. I think I saw that you do have the Balsapr 3200kV brushless motors (didn't I?).