Great Planes Ultra Sport 46/EP ARF - RCGroups Review

Join us as reviewer Nikolei Zinsli flies this throwback ARF, the Great Planes Ultra Sport 46!

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Great Planes Ultra Sport 46/EP ARF RCGroups.com Review

Product:Great Planes Ultra Sport 46/EP ARF
Wingspan:55"
Length:49.5"
Weight:5.5-6.5lb
Recommended Power:.46-.55 cu 2-stroke, .70 cu 4-stroke or 480KV/75A ESC/6S 3600mAh Electric setup
Price:$199.99
Available from:GreatPlanes.com
PDF Manual:Click Here

Anyone in the hobby for any length of time will surely know of the Ultra Sport. Having earned a reputation for one of the best flying sport models around, the Ultra Sport has become a staple for new pilots that have mastered their trainer and are looking for something more aerobatic. The symmetrical airfoil will perform any sport aerobatic maneuver and then slow down for a smooth landing. Having been in kit form in at least 3 sizes since the 90's, Great Planes has finally released an ARF version complete with retracts! The new ARF of this classic airframe includes mechanical retracts, a large hatch for battery and on-board gear access and can easily be built for glow or electric power. Ok enough already, let's dig in and check it out!

In the Box

The Ultra Sport ARF came in a full-color attractive box that when opened, revealed all of the parts nicely secured to each other and the box.

The construction of the plane looked to be well done and about what you'd expect to see if looking at a kit-built Ultra Sport. I actually compared my kit-built Ultra Sport wing to the ARF wing, and they were nearly identical.

While inspecting the covering, I noted some patches of what appeared to be CA residue on various areas of the covering. This concerned me at first, but a quick wipe with some Acetone cleared it up easily. There were some notable wrinkles & bubbles (likely due to temperature change during shipping), but we'll tackle those once assembly starts.

The cowl was of a nice thickness, and painted well. The other accessories looked to be pretty standard compared to other ARF kits of similar size. Several wood parts are provided that will allow setup of nitro or electric power.

I'll be powering this with an OS 46 AX I had available, and some standard Futaba servos, a retract servo and a Tactic Rx with 6v NiMh pack.

Assembly

First off, the manual is very well done with pictures accompanying most of the steps. Before getting into it, I spent some time going over the whole plane with my heat gun and iron. I managed to get out most of the wrinkles, but I couldn't do much about the bubbles. Not a huge deal, only really visible up close. I also took this opportunity to ensure the CA hinges were all secure, as they all come pre-glued.

Wings

The manual starts us off with the wings, which seems as good of a place as any. The servos, control horns and rods were installed without difficulty. I chose to use a Z-bend on the servo arm side of all the control rod connections for this plane as opposed to the L-bend nylon Faslinks provided. Either will work fine. With the servos in, I epoxied the spar halves together and the alignment pins into the wing halves. With the spar cured, I mixed a large batch of epoxy and joined the wing halves together. A clamp or two in the hole on the top center of the wing will help make sure they are tight together until it cures.

The retracts required you to remove some grub screws in order to rotate the spring coil to be in the right direction. Didn't take too much time, but could be easily missed if rushing the build. Once the retracts were setup, axles installed and control rods attached, I installed them into the wing and connected them to the servo. After installing, I noticed a note in the manual that I had missed, indicating that if using a glow engine (as I am), to coat the inside of the wheels wells with thinned epoxy. Some ABS wheel wells would have given a nicer finished look here. I did end up removing the retracts to coat the inner area with thinned epoxy, which didn't take long. Had I thought about it before, a quick coat of black paint before sealing with epoxy would've looked nice.

I plugged the retract servo into my receiver for a quick test before declaring the wing complete. Initial tests worked the right way, but they did not retract all the way up into the wing. I adjusted the travel endpoints to XX (up) & YY (down) which worked perfectly (your numbers may vary).

Fuselage

With the wing mounted to the fuselage, I checked alignment and squareness of the horizontal stab before gluing. No modifications were needed and both the vertical and horizontal stabs were glued in and left to cure. Then the rudder & elevator servos, control horns and rods were installed and setup without issue.

I'll be powering this Ultra Sport with an OS .46 AX. I've been doing a lot of electrics lately, and miss the smell of nitro in the morning! With the power system established, I decided to mount the engine on its side, as opposed to the 45-degree option. This will allow the muffler exhaust to go mostly under the wing, instead of right on top. I may add a exhaust deflector later to help keep cleanup to a minimum. Now that we have the power option and mounting decided, I was able to drill the pre-marked locations for the motor mount, install the blind nuts and place the engine on the mount to check for proper distance from the firewall.

Some of the supplied wood pieces will be needed to make the fuel tank tray and throttle servo tray mount. The pieces went together just fine and before I knew it, the throttle servo was mounted and connected to the carb on the engine! The control rod required a slight bend because I drilled the firewall for the pushrod tube at the pre-defined spot which was a little low for this particular engine. No big deal, but before drilling the hole for your pushrod, take a look at your engine to determine the best location. Finally, I used a block of foam under the fuel tank and strapped it in tight with the supplied velcro before pulling the lines through the firewall and connecting them to the needle valve and muffler.

Last but not least, cutting the cowl to fit! The steps outlined in the manual have you cut the cowl before it is mounted. I used the template as a starting spot to which I opened the hole inside of my guide line and slowly worked out with constant checking against the engine. If you keep the muffler and glow plug off, you should be able to slide the cowl over the engine while it's mounted. You may have to unscrew & remove the needle valve also depending on where yours is. You also shouldn't have to cut your cowl lengthwise as noted to fit the cowl on with the engine mounted. I drilled 2 small holes inline with the muffler bolts so I can easily remove the muffler if I need to remove the cowl. You'll notice in my final picture that the hole is a little big around the carb...this is because the cowl ended up needing to be angled more from where it was when tracing the template.

With everything finally in their place, I mounted the wings and set it on the balance stand. The manual recommends the CG at 2-7/8" - 3-1/2", and mine came out right at 3". On the scale, I'm looking at 5.5 lb AUW.

Completed Ultra Sport ARF

Flying

Takeoff & Landing

A little rudder was used to keep it tracking straight as it gained speed, but the Ultra Sport was off the runway in no time at all. It needed some aileron and elevator trim, but we had it flying straight within the first lap. Takeoff power was perfect with the OS .46 on the nose and once in the air with the gear up, the top-end speed was nice and quick.

With a flip of the gear switch and a pass to ensure they were down and locked, the Ultra Sport was slowed down and setup on final for the runway. Before landing, we took it up a few mistakes high and did a stall test. It slowed down very nicely and with full up elevator held in, the stall was pretty tame for a sport plane; the right wing dipped a bit, but there was no tendency to snap out. With this knowledge, landings proved to be perfectly predictable and easy. The Ultra Sport glides well, so greasing the landing was fun and not difficult. I can see lots of touch n goes in my future with this plane!

Aerobatics

This little plane is a lot of fun! My test pilot and I put it through all of your typical sport aerobatics and the Ultra Sport did very well. Snaps, point rolls, loops, cuban eights and whatever else you can think of are easily accomplished. Alex even did a set of rollers and rolling circles and was impressed by its performance. Spins were also fun, but don't expect it to flatten out much, there simply isn't enough elevator for a flat spin.

With lower rates set, slow rolls and low inverted passes kept us smiling until the timer beeped suggesting we land soon.

Flight Review Video

Great Planes Ultra Sport ARF - RCGroups Review (9 min 29 sec)

Flight Photo Gallery

Summary

The Great Planes Ultra Sport ARF will take you back to good times with this classic airframe that has held its own for decades, without the time investment of the traditional kit. Assembly from box to runway was very quick thanks to the well illustrated manual. Sure, the covering was a little rough and some wheel wells would have been nice, but those minor things kind of go away once you get in the air and realize how fun and relaxing this sport plane is. It shows no bad tendencies in the air, has plenty of ability to do all kinds of sport aerobatics, and lands with ease. I could easily recommend the Ultra Sport as a second or third plane for a pilot that has mastered their trainer.

Hits

  • Return of a classic airframe without the build time
  • Attractive covering scheme
  • Easy build for nitro or electric power
  • Mechanical retracts included
  • Thorough manual with pictures
  • Standard equipment needed means low overall investment for you

Misses

  • Covering wrinkles on stabs, micro bubbles under trim pieces (YMMV)
  • No wheel wells provided, shows internal wing structure on bottom
  • Strange cowl cutting & mounting step ordering for nitro option

*Thanks to Great Planes for supplying the Ultra Sport for review, and to my pilot Alex Fredrickson for piloting it for photo & video coverage!

Last edited by Matt Gunn; Apr 24, 2017 at 10:46 AM..
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Apr 24, 2017, 12:29 PM
AMA 537620
ChillPhatCat's Avatar
Great Review, thanks for sharing. The US 40 was available as an ARF for a while, this is basically the same plane... wing looks like it may be mounted slightly lower or the fuselage is not quite as tall, as there used to be a full belly pan... an interesting change that has to be intentional. What a fantastic flyer though, never heard from a pilot that disliked flying one. Wish I still had my kit built 40!
Apr 24, 2017, 02:03 PM
If it's R/C, I LIKE IT!
Nikolei Zinsli's Avatar
Yep it's not the first ARF, but AFAIK this is the first with an electric option and first to come with retracts.
Latest blog entry: 93" AJ Laser 230z
Apr 24, 2017, 07:41 PM
Kit Manufacturer
coreman's Avatar
Can the wing be built with fixed gear? No way the plane will survive long on my rough home field and being a closed landfill, we can't really smooth it
Latest blog entry: BluFO review by Jim T Graham
Apr 24, 2017, 09:17 PM
If it's R/C, I LIKE IT!
Nikolei Zinsli's Avatar
Hey coreman! The gear are actually pretty robust, but you could craft some ply blocks to attach to the retract rails. Would take some planning but shouldn't be too difficult!
Latest blog entry: 93" AJ Laser 230z
Apr 24, 2017, 10:57 PM
Kit Manufacturer
coreman's Avatar
Quote:
Originally Posted by Nikolei Zinsli
Hey coreman! The gear are actually pretty robust, but you could craft some ply blocks to attach to the retract rails. Would take some planning but shouldn't be too difficult!
I loved my UltraSports I just don't have the time to build the kits I own. The two pictured are no more. Well, the US40 needs a wing panel. The US60 disappeared into a swamp 4 years ago. The US60 originally had retracts but they kept bending so much that I had to build a fixed gear wing.
Latest blog entry: BluFO review by Jim T Graham
Apr 25, 2017, 01:37 PM
Registered User

Thanks for the excellent review.


I'm just in the process of assembling mine. My covering seems ok.
I am using a Hitec retract servo and I found that the 16mm throw mentioned in the manual is too much and should probably be about 12mm with a 180 degree throw retract servo. I have realised since that if I had used 32mm with the servo arm at an angle I could have achieved the same thing: dumb.
I've painted the wheel wells black, but the tatty edges bother me a bit, I'll have to try and tidy them up.
I splashed out on an OS Max 55ax and I'm very excited about this model.

Do you think it would benefit from programming in flaperons ?
Apr 25, 2017, 02:54 PM
Kit Manufacturer
coreman's Avatar
Quote:
Originally Posted by Richard Haynes
I'm just in the process of assembling mine. My covering seems ok.
I am using a Hitec retract servo and I found that the 16mm throw mentioned in the manual is too much and should probably be about 12mm with a 180 degree throw retract servo. I have realised since that if I had used 32mm with the servo arm at an angle I could have achieved the same thing: dumb.
I've painted the wheel wells black, but the tatty edges bother me a bit, I'll have to try and tidy them up.
I splashed out on an OS Max 55ax and I'm very excited about this model.

Do you think it would benefit from programming in flaperons ?
I had flaperons/spoilerons on mine and they didn't hurt but the benefit was minimal. They are very clean planes and you really need to get them nose high to bleed off the speed because they will glide forever. it took me an entire day to figure out the best way to land mine and that was a full day of going up and shooting landings. having a little headwind will help immensely (that said, mine were kit built not ARFs but that shouldn't effect things at all)
Latest blog entry: BluFO review by Jim T Graham
Apr 26, 2017, 10:43 AM
If it's R/C, I LIKE IT!
Nikolei Zinsli's Avatar
Glad to hear your covering was ok. Mine was mainly wrinkly on the stabilizers, along with tiny bubbles under the trim areas. Figured it was a YMMV issue.

I agree about the 'tatty edges' in the wheel wells, but for this price there isn't much room to complain for such a good flying plane. These kind of things a superficial and can always be improved with a little time and elbow grease.
Latest blog entry: 93" AJ Laser 230z
Apr 28, 2017, 02:18 AM
rip
ripacheco's Avatar
How is the performance on electric version?
Apr 29, 2017, 11:29 AM
Registered User
jpurcha's Avatar
I liked the review and the video. I have the 60 kit at home on a shelf. I sold the 40 a couple of years ago mainly because I have a Tower Kaos, Super Kaos 40 built and an Utter Chaos 40 in a box. These are all suppose to fly very much the same. Have you flown any one of these for a compare the flight characteristics.

Saw the kit in the local hobby shop, nice that it comes with retracts.

Jim
Apr 30, 2017, 04:43 PM
Registered User
cmmicroheli's Avatar
This is a perfect match for a Jett 56lx!
May 01, 2017, 07:34 AM
AMA member since 1974
FlyBigElectric's Avatar
I have the electric setup with a 480kv motor, 14x7 prop and 6s 5000mah battery. It has excellent power with this setup and it a really fun plane to fly.
Last edited by FlyBigElectric; May 01, 2017 at 03:14 PM.
May 01, 2017, 09:09 AM
rip
ripacheco's Avatar
Quote:
Originally Posted by FlyBigElectric
I have the electric setup with a 480kv motor, 14x7 prop and 6s battery. It has excellent power with this setup and it a really fun plane to fly.
6S 5000 mAh battery?
May 01, 2017, 10:01 AM
AMA member since 1974
FlyBigElectric's Avatar
Quote:
Originally Posted by ripacheco
6S 5000 mAh battery?
yes


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