Category: <span>ARF</span>

63″ Art Scholl Chipmunk from Seagull Models

Landing Photo-Mike Duran

I wasn’t in RC during the time that the Goldberg version of this plane in this size was out. I bought and still have the park flyer version of the plane, so I was excited when Legend Hobbies announced Art Scholl’s Super Chipmunk in the 63″ size. I ordered on Jan 5 and got it in early May, as described on the pre-order form. Thanks to Legend Hobbies for the goodies with the order and for the solid communication throughout.

Above is the Goldberg park flyer version of the Art Scholl Chipmunk. I bought this a few years back. I replaced the old geared motor with a brushless and it flies great.

The instruction manual wasn’t great, but I think most anyone who orders this plane will know how to assemble it. It is very straight-forward. Pay attention to the tail wheel/rudder assembly. It’s the only thing that was a little different for me, and for warbird guys it’ll be familiar.

It went together well, required very little modification etc. So far I have used the split elevator pushrods as supplied, but since removing the flap servos (more on that later), I will likely add dual elevator servos.

Most of my flights are on a wide open, 800′ grass runway. I certainly don’t need flaps to land this plane on that runway. I have landed it on a shorter, paved runway with no flaps and no problem as well. Because of these things, I glued the flaps in place. If I don’t need them, there’s no use in carrying around those two servos and cables and pushrods etc. Five grams of epoxy and nobody will ever know the difference when viewing from above.

As with all planes this size, I went with MKS HV69 servos throughout. The radio runs on a 2s 1000mAh lipo. I can’t say enough about these servos on a plane this size. They weight nothing, have tons of power and center very well. Servo holes need to be adapted on most arfs, but this is easy enough.

I originally planned an eFlite Power 60 470kV for this plane. But when I got it and took a glld look at it, weighed it and estimated final weight, the eFlite motor wasn’t enough. It is an 1800 watt motor and I wanted raw power. I estimated the plane at 10.5lb early on.

I found a Dualsky 5060EA V3 400kV that was a 2200 watt motor and weighed 393g, against the 1800 watt eFlite motor at 380g. That was an efficient power/weight increase, +22% in power for +5% in weight. I ordered the motor at noon on a Monday, from Dualsky in China. It arrived that Thursday by noon for their basic shipping rate. I put a Castle Edge 100a ESC on it and run a 3 blade Master Airscrew 13-12. All up weight is right around 9 lb 12oz. See the Ecalc profile.

AUW is right around 4500g.

It flies well, tracks well, but you want to keep speed through turns. It’ll snap when you bank if you get too slow. I did that at altitude to test it. A club member mentioned that he had the CG version years ago and it had that tendency. This one does too. I won’t float through turns like my pattern planes do.

There is a bigger one coming at Legend Hobby. Hit them up. I enjoyed doing business with them.

Another 62″ AJ Acuity Pattern Plane

I just assembled my 4th Acuity. My first one was a 62″ that I bought when I started flying pattern. I soon bought a 2m Acuity and flew it and eventually sold my 62″ version. A few years later, after lightly crashing the original due to a faulty cheapo servo cable, I bought another 2m Acuity. They really are hard to beat, either version, for the money. I’ve had much more expensive planes, but the Acuity stands its ground when compared.

After deciding last year not to travel for pattern contests any longer, I scaled things down so I don’t have to have to accommodate 2m planes. So I sold my 2m planes and bought another 62″ Acuity.

This Acuity is far and away the best quality I’ve seen on one yet. The others were all fine, but this one was perfect. I haven’t purchased many ARF airframes that didn’t need at least something to make the setup measurements perfect. No need for blades, shims or sanding on this one.

The canopy attachment did require work to use without the supplied thumb screws. I added a small piece of light ply, some fiberglass cloth and some Epoxy and was able to create a nest for the spring loaded canopy latch attached to the fuse. I basically filled n the area between the rear screw for the Tcan and the rear edge of the canopy with glass cloth and epoxy, let it set then drilled it out and coated it with thick CA and accelerator. I sanded inside the hole and now it’s a hard area for the canopy latch to hold on to. In the past, I have just used the thumbscrews to hold on the canopy. I am determined on this one to use only the top latch. We’ll see…

I already had the AJ motor used for 5s on this plane. I bought it for a project that I have yet to complete, so I reappropriated it 😉 It is the AJ4025-14P 485kv. It appears to match perfectly with a Hacker A50 12s when compared on eCalc. The Hacker is rated at 480kv is the only difference. So this plane will run on 5s power. It will help with weight for sure.

My first 62″ Acuity was powered by 6s with a Hacker A50 16s, which is the 6s version. It had boatloads of power and was always a little nose heavy, even when I moved the rudder servo to the aft position. You might think that running the same plane on the same prop and getting more thrust on 5s than on 6s isn’t possible. Look at the two images below. They are eCalc profiles of this plane with the 5s motor and the 6s motor. You give up a little flight time, and maybe tax the motor just a little more on 5s, but overall, the 5s setup is more efficient. It generates about 10% more static thrust on 5s.

My 6s Acuity was 3600g all up. This 5s version is 3060.

EDIT:
Before even flying this plane, I was looking for a motor for another plane and came across a Scorpion SII 4025 440Kv motor. This motor weighs less than the AJ motor I planned to use and gives this Acuity all the power it would ever need. So I installed the Scorpion motor. It bolted right up to the pre-drilled holes on the plane. It added 1.8mm to the gap between my spinner backplate and cowl, but I had it fit very closely before, so I’m not going to re-drill my mounting holes on the cowl. I’m good with a 2mm or less gap. I have included an eCalc profile below for the plane with this motor. It has tone of power and hardly taxes the motor at all. I might have just found a new favorite motor.

SECOND EDIT:

The Scorpion motor mentioned above is a total bad ass of a motor, but it is just too much for this plane. I would never use the top half of the throttle range, so I took it off and will use it on the new upcoming project, a Super Chipmunk in the Art Scholl scheme. I went back to the AJ 4025-14P on 5s for the Acuity. It gives me all the power I need and we lose almost 5 ounces going from 6s to 5s.

After a few flights, this 62″ Acuity flies beautifully. These planes really do offer great value.

I used MKS HV69 servos for all surfaces on this plane. These are great servos for a plane this size. They center very well and perform very well when running on straight 2s lipo power. I use a 1000mAh 2s Lipo for the radio and can fly all day without needing a charge on the system battery.

The HV69 requires a little bit of changes in the servo bays. I add a small piece of 1/8″ ply to extend the area where the servo is screwed down. I make lite ply covers and fit the HV69 in them. It requires just a little work, but gives you lightweight, powerful, fast servos that don’t require a voltage regulator. The servos are very stable because the lite ply cover holds them in place when screwed down.

I haven’t flown this plane yet. I plan to in about a week.

CK Aero Allure Pattern Plane

OK, so there for a while, I might have gone pattern plane crazy. A friend had this Allure ready to fly and wanted to sell it. So I drove down to Houston and bought it. This was a great flying airplane. It flew better than the Alchemy I built in my opinion.

I flew this plane for a year or two and ended up selling it and moving on. I guess my attention span is kinda short with things like this, but I feel like I need to try all of the different planes.

These CK Aero planes are the real deal. They are pricey, but there are deals to be found on them either used or at the end of the year, like when I bought the Alchemy builder’s kit.

Bryan Hebert and I worked together back in the early 80’s. We both flew RC back then as well. I have known him for a long time and can say that he is a straight up guy and a good person to do business with.

CKAero Alchemy Pattern Plane

At the end of the year, Bryan Hebert at CK Aero had one Alchemy builder’s kit left. This is the plane with a prebuilt and painted fiberglass fuselage with foam wing and stab cores.

This was my first balsa over foam sheeting job in a long time, but it came out really great. I originally fitted the plane with a Hacker Q80, but ended up putting a Plettenberg Advance in it and it performed much better.

The plane flew very well. I ended up selling it to a friend because I had two other pattern planes and didn’t have room for them all.

Acuity 62″ Pattern Plane – AJ Aircraft

So after about a year back in RC, I got bit by the pattern bug. I looked around and contacted some friends to see what I might have been able to buy used from someone, but didn’t really find exactly what I wanted.

On the recommendation of a friend, I looked at AJ Aircraft’s Acuity. It comes in a 2 meter version as well as a 62″ version. For many reasons, mostly because this will be my first season to fly pattern, I went with the 62″ version. Also, I already had the 6s 5000 mah batteries that I needed to run this plane as it would be set up.

I set this plane up with a Hacker A50-16s. I used a Castle Creations Edge 100 amp esc, which is too much, but again, what I had and perfectly suitable for that setup, so on it went.

I propped it with a XOAR 16-10e wooden prop for now. The 16-10 seems to pull it just fine. It is not fast and I do use WOT in an upline, but it has plenty of power and great flight times. After 7 minutes of pattern flight, I still have about 20-25% of my battery left.

I moved to this plane from my Kaos. It is much different than the Kaos. After flying this plane for a while, the Kaos feels like it weighs 3x as much, even though it doesn’t. AUW on the Kaos, with the 6s/5000 is 7lb 14.6 oz. AUW on the Acuity 62″ with the same battery is 6lb 15.4 oz, so it’s really only about a pound lighter. The Acuity is so much more maneuverable and so much more agile… it’s a joy to fly. Learning to fly the pattern with the Acuity in a crosswind is more tricky as it is more susceptible to deviation from crosswinds. It “weathervanes” more than the Kaos did. A wise person told me that learning to fly pattern is all about learning to use the rudder, and that is correct in my experience.

WEIGHT BREAKDOWN

Fuselage (rtf no batt): 3 lb. 14.4 oz.

Canopy and thumb screws: 5.6 oz.

Right Wing: 8.3 oz.

Left Wing: 8.4 oz.

Wing Tube: 1.2 oz.

Gensace 6s/5000mah Lipo: 1 lb. 9.5 oz.

Total AUW RTF: 6 lb. 15.4 oz.

The CG is supposed to be about a half inch behind the wing tube. With my 6s/5000 all the way forward, mine balanced perfectly. This is great because when I move the CG back later on as I set it up for snap rolls and other maneuvers that perform better with a CG further back, I simple will move my battery back on the tray. There is a good 3-4″ to do this. I’m not sure if this was incorporated into the design, but it worked out perfectly at least on my model.

I set my plane up very simply with a Spectrum AR610 receiver and Hitec Digital Mighty Mini servos for elevator and ailerons and a full size high torque Hitec digital rudder servo. I am not running a separate receiver battery.

Overall, I love this airplane. For about $450 delivered, I found it to be a great value for an entry level pattern plane. It will no doubt carry me much further than the Sportsman class as well.

It was packed brilliantly in a large box with lots of compartments and using lots of tape… instead of styrofoam. It had foam where needed, but it is very smartly packed in a non-wasteful (and easy to dispose of) way. Assembly is very simple and straightforward using the PDF building plans available on AJ’s web site.

Below is an eCalc report on the setup of my Acuity 62″.

eCalc result for Acuity 62″ setup with Hacker A50-16s on 6s/5000mah lipo with 16-10 prop

EDIT 5/31/18

I’m a little over 100 flights in and loving this plane. I haven’t pushed it aerobatically. I’m sticking to perfecting the Sportsmans pattern with it. It’s competitive against the litany of 2 meter planes that i have faced in competition as long as my thumbs are cooperative.

I’ll soon be ordering the 2m version and moving the 62” to backup status.

Tower Hobbies Kaos 60 ARF – Electric Power

The Kaos is a classic style for sport/pattern flyers. It’s stable, aerobatic and the long moment really makes this a predictable and smooth flying plane.

I have never bought an ARF and assembled it. I bought my Tucano used but not flown, so the Kaos was my first complete ARF experience.

There are at least three of these that I know of in my club. I wanted to make mine different and the modeler in me told me that if I didn’t have a substantial time investment in the build that I wouldn’t enjoy it as much. For those reasons, I decided to remove the covering on the ARF and make this plane my own.

I went with metallic finish Monokote for the job. Removing the old covering was very easy. The first step in the assembly process for this plane is to heat up and make sure the factory covering is all stuck well. They don’t get too detailed making sure everything is stuck well from the factory. For this reason, the old covering came off very easily with my heat gun.

I fitted this plane with the Rimfire 80 from Tower Hobbies. It’s a lower RPM motor than the 60. At a 500 Kv rating, it will swing a larger prop at a lower RPM. I installed a Castle Creations 100 amp ESC to go with it and fitted it with a 15-8 prop and powered it all with a 6s 5000mah lipo. It has about 2″ clearance with the larger diameter prop.

It flies very well. It is quiet and has lots of reserve power. Flying weight is 7 lb 14.6 oz. and it took 4 oz in the nose to get the CG to the 4.5″ location I wanted.

The Bolt-on Tail

The plans for this plane tell you not to glue the tail together, but to use the bolt to bolt it down. It all fits together very well, but this goes against everything I have ever learned about RC aircraft. I called Tower Hobbies and spoke to their support people. What I got was that they have not had problems with the bolt-on setup, but if it were his own personal plane, the guy I spoke with would glue the tail together. That was enough for me to mix a batch of epoxy and do just that.

Phoenix Models Tucano GP/EP ARF

I rescued this airplane from hanging from the ceiling in my local hobby shop on consignment. It is an ARF (Almost-Ready-to-Fly) model. It had the electric motor and the speed control and all of the radio equipment installed.

This airplane is made to accept retractable landing gear. Today’s modeler can get all kinds of landing gear that don’t require any outside servo. They just plug right in to the radio and mount onto the plane and you’re off and running with retracts. The problem is, you hear people complain about them a LOT. You see them fail a LOT. Tower Hobbies had these retracts that are made just for this airplane. They require servos to do the work, but I find them a lot more reliable and durable than the cheaper servoless models. Plus they are kinda old school, so I went with them.

The guy who put it together mounted an Elite Power 52 Brushless motor on it. This motor is rated at 590 K/V and will take a 6S battery. With the extra weight of the two retract servos, I opted for 6S power. I propped it with an APC 12-10. It has a Castle Creations Lite 100 ESC that seems to work just fine. It has a consistent beep every few seconds to let you know that it is armed. The instructions say you can remove that beep if you use Castle’s programming interface for the ESC. Problem is, this works only on Windows computers and I haven’t had a Windows computer in my house since the early 2000s. So I live with the beep.

With the Power 52 motor and the 6S 45C 5000mah battery, I get crazy fast flight for about 5 minutes. The plane sets up and lands better than anything I have. It is smooth and very, very stable on landings.

I added 3.5 oz to the tail to get it to balance.

Overall, I really like this airplane. It’s very aerobatic and has lots of reserve power. I get lots of comments on it.