The complete radio control model airplane FAQ.
Magic 3D Fun Fly Model Airplane Review, powered with a Thunder Tiger .36 Pro engine
By Cliff Griffin
Jump down to the First Impression...
Jump down to maiden flight write-up...
The bottom line:
This is a great plane, with the typical little annoying ARF "features"--although it's the best looking and best building ARF that I've ever seen. I love the low wing loading, high rates aren't quite high enough, but it mellows out enough with low rates that you could use it as a second plane.
I've been working on assembling the
kit. It's one of the most complete ARF's that I've put together. I think part of
that is due to its simplicity--no wheel pants, no cowl, no fluff...it's even got
a factory one-piece wing, so you don't even have to join that! Unfortunately, it
uses rubber-bands to hold on the wings.
I'm dying to see how it balances! I've got a TT .36 Pro that I've been wanting to fly, but I also just picked up a Magnum .61 FS...the TT is right at 11.3 ounces, and the four stroke--get this--is only 4.2 oz heavier! You don't have to guess which will be stronger! I just want to see where it will balance, though, so I can pick the engine. I guess if I have my choice, it'd be the Magnum, since it's brand new. The thing has practically enough prop clearance to put a 1.20 on it. (Uh oh...I hope I didn't just give somebody a BAD idea. This plane is so light that it doesn't NEED that kind of power! I know my .61 will be way overkill...)
The front wing rubber-band dowel interferes with the stock fuel tank position. The instructions are minimal--NOT for an inexperienced builder. They also have a pic here and there that's either a duplicate, mis-marked, or just plain missing.
The covering job is about the nicest I've seen on an ARF. They used some cheap monokote look-alike. One thing they missed, though...on one aileron, the seams don't come together. There's a hairline of balsa exposed the full length of the aileron.
Kit contents total 30.6, for everything except the decals. I removed each item from the bag, with the exception of the hardware.
Add 5 servos, 1.5oz ea, a typical 17oz .46 engine, prop, Rx, battery, and a little fuel tubing and some adhesive, and you double the weight with another 31.5oz. That adds up to 3lbs 14oz. I'd be interested to know how they got theirs down to 3.0 lbs, which is the specification. I suppose if you use lighter servos, you can cut 2.5oz, and a TT .36 will bring it down to 3lb 6oz...but they recommend metal geared servos, so that's not even really recommended... My final, ready to fly weight was 3 1/4lbs with micro servos, the ultra-light engine, and an ultra light NiMH battery pack.
Then I put
it on the CG Machine, and weighed the tail, without the engine...
I think you may have to add tail weight even with a very light engine. I haven't added my engine yet, but I put it on my CG machine, and put a scale under the tail wire. With my small 1.5oz battery under the tank, the scale read 4oz. I entered that into my Excel calculation, and at 26" out from the CG, my calculations show you need about 12oz on the nose, between the engine, mount and prop. If that is correct then you'll need tail weight even with the smallest of engines. Moving the battery back and the servos back just a touch made it much closer.
Construction looks decent, as good as most good ARF's. It's not sticky-back covering, but some shrink-on kind. You can't see any construction in the wings, because it's one piece and fully covered when it arrives. The finish work under the covering is smoother than any other ARF that I've seen, though--the covering is very smooth.
I still haven't decided which engine to use...my Magnum 4-stroke is begging to be run, and it will be the easiest to install because of the muffler. The TT .36 want to be run, but it's not screaming as loudly, and the muffler routing isn't as favorable. There's only a 4oz difference between them, anyway.
The tank positioning is also kind of a pain--they put the engine thrust line very high up on the firewall, so that elevates the carb. The tank is supposed to fit in a convenient hole, but the rubber band dowel gets in the way. I may have to cut & fill the hole. I'll let you know after I look at it some more tonight or tomorrow.
Maiden Flight Impressions...
I made my maiden flight on my Magic 3D today. (Well, ok, Roger did, but I flew it after that.) It was a lot of fun. It came in at 3 1/4lbs dry, using a TT .36 Pro (w/alum. spinner nut, no spinner, 10x4 wooden prop), a tiny 1.5oz AAA 720mAh NiMH battery pack, 2 std servos on the ailerons, a micro HS-81 on the throttle (and I must say, these kind of suck for throttle--if there is any minute amount of micro-drag on the throttle rod at all, it doesn't center the same coming up or down--the servo is very weak near center, which allows for a great big dead-band), and two Multiplex Micro MC/V2's 1oz digital metal gear servos for the tail. Oh, yeah--I replaced .8oz of metal pushrods with helium filled Kevlar thread for the pull-pulls on the tail. The spec's call for 3.0 to 3.5 lbs. I was right in the middle of that--but I using the lightest engine recommended, and lighter servos than was recommended, (they suggest "strong, metal gear servos") and I had eliminated 3/4oz of metal on the pushrods. I could remove an ounce by replacing the aileron servos with micros, but other than that, without major modification, this plane is impossible to bring in at 3.0 lbs using the recommended equipment. You could shorten the firewall--so it doesn't need lead on the tail, replace the heavy tail spring with a lighter wire, use a lighter servo mounting plate, even smaller battery, and even then...I doubt it would come in at 3.0lbs.
CG Notes: It is slightly NOSE heavy with this combination, and I put the servos as far back as they'd go, and the battery and Rx back as far as it would go without significant mods, too. (I had to fill in the front of the fuselage's servo cutout holes so the micro's would bolt in.) If you are going to assemble this plane, note that the TT .36 Pro only weighs about 11.3oz, with the muffler--this is 4.2oz lighter than a Magnum .61 4stroke, and 5-6oz lighter than most .46's. If you plan to use a larger engine, plan to put lead on the tail. The engine had "enough" power with the Flop Flight 10x4 popsicle stick prop--I look forward to trying it with an APC. You could point it up and then accelerate, but you had to be going slow in the first place to do that.
The plane was fun, and would fly at a walking pace. It was so easy to fly that I'd say it would even work as a SECOND PLANE! (In such a case, just make sure to keep the rates down, and the speed down, with a low pitched prop.) I need to add some lead to the tail. If you got the throttle setting right, and the right attitude, it would torque roll on its own. Even on high rates, once it started to tip over, even the club's hovering maniac would lose it, and it would quickly drop off one way or the other. He made a comment about the throttle. saying it would suddenly come up on you--after thinking about it, I'd bet that it is due to the backlash in the HS-81. I ran it out of fuel once, at about 30' or so elevation while coming up for a hover--when it died, I just pointed it straight down to get some speed, and pulled the elevator at about 8', and made a nice landing in the weeds--albeit I practically rolled it right into the fence.
Without even using flaperons, you can blip the throttle and elevator for some 4' loops. The plane is amazingly docile, even on high rates. Sure, if you hit the throttle wide open and get some speed up, it can get a little wild...but since I forgot to seal the hinge-lines, I tried to keep the speed to a minimum.
This plane has such a light wing loading that I'm sure it would be very well suited for electric conversion, or even as a float plane. It's got about 725 sq" on the wing--more than most big sticks and trainers, yet it weighs 2-3 lbs less. I'd definitely put on a larger engine if I were to do the float thing. I mostly fly my 80" MW Extra, along with some buddies who have 105" Edge's. For toting them around by hand, we usually just lift the rudder and tow it. The Magic has such long landing gear that--just for effect--the first time I brought it from the car to the pit, I towed it by the rudder. It sure got some chuckles. The gear is so long that you could easily swing a 16" prop, and only worry about strikes on hard landings--this may be fun for somebody with one of those .60 RCV jobs that have a 2:1 gear-down on the output. Then again, you may not be able to land it with that setup--mine practically floated forever even with the 10x4 idling.
The instruction manual sucks, and isn't for newbies. I'd recommend getting assistance if you haven't put together several planes. The pictures were mislabeled, one page had the same pic in it twice with two different Pic #'s, and some pics were just missing. The plane wasn't difficult, at least--especially with the one piece wing. The majority of the work was installing the engine, servos and linkage.
The TT .36 Pro is a great engine. I bought it used over a year ago, but hadn't gotten around to mounting it yet. It had LOTS of compression, but with the glow plug removed, it turned very freely. I primed it, glowed it, and it fired on the first flip--using a Bic as a chicken stick (hey, I just had to see, before I grabbed the starter motor...). Unfortunately, the head was slightly loose and leaking a tiny bit, and when I pulled it off (to see if the gasket was there), it looked like it had been leaking for a while on the previous owner. An allen wrench proved that he'd used the wrong size on the head bolts, so a couple were rounded out slightly. Throttle response was good and smooth, although not a fast & instant acceleration. It probably needs to be leaned on the bottom end just a touch; it would load up just a bit if I let it idle too long. A smaller prop wouldn't hurt that much, either. After all, I was turning a 10" prop with a little .36. I didn't think about taching it. We did try a 10x5 on the maiden flight, but Roger said it flew better with the 10x4. There's plenty of speed with either, but the 4-pitch had better vertical power. Like I said earlier, I look forward to trying it with an APC! Down-line breaking was great. Once again, I'm sold on the premise: "lighter flies better!"
The worst part of the plane is that STINKIN' GLOW FUEL SLIME EVERYWHERE!!!! I LOVE MY GASSERS!!! Too bad there aren't any tiny gas burners that can run with good power/weight ratios. I was disappointed when I found out that it has a SEMI-Symmetrical wing, too--this kind of a plane should have a fully symmetrical wing! That, and rubber bands hold the wings on. Inverted flight took quite a bit of down elevator. Sure, some of that may have to do with the CG, but I'd bet not all of it. Also, the fuel tank will NOT install if you follow the instructions. The hole in the firewall was too high, which caused the fuel tank to hit the front rubber-band dowel. I had a similar sized tank that had the stopper a little higher, and used it with success.