|Wingspan:||2.0 m (79")|
|Wing Area:||30.6 dm2 (477 sq. in.)|
|Weight:||40 Oz AUW W/LiPo Battery|
|Wing Loading:||11 oz/sq. ft. W/LiPo Battery|
|Wing Servos:||Hitec HS-5125MG|
|Tail Servos:||Hitec HS55|
|Transmitter:||Multiplex Royal Evo 12|
|Receiver:||Multiplex RX-9 Synthesized DS IPD|
|Battery:||Max Amps IB1400 OR 3S1P 4000 Lipo|
|Bench Testing:||Aircraft World's Emeter Data Logger|
|In Flight:||EagleTree Systems USB Flight Data Recorder|
|Model Available From:||Icare RC|
As the Pacific Northwest rains started to recede, my thoughts turned to summer and a new project. I wanted a plane that was versatile as far as locations to fly, could thermal well, but could be used in competitions too! These considerations led me to the SUV of sailplanes, the LMR. LMR stands for Limited Motor Run format for competition sailplanes. In this format, pilots are given several parameters to fly against while still being allowed to run a motor if needed to complete the task. As I started my research, I discovered that some people are now using outrunner style motors in LMR planes. This intrigued me as I have loved the outrunner motors I’ve used, but had never thought of them for this application. One reason for this might be the fact that most sailplanes are too skinny in the nose to accommodate an outrunner motor comfortably.
As luck would have it, I happened upon what I feel could be the perfect combination. The new Magellan-E from Icare is a new generation sailplane based on the awesome Carbon D light plan form, but with a wider open nose suitable for an outrunner motor. The other element is that Hyperion came out with the new Z3025-06 motor targeted directly at the LMR application. I had never used any Hyperion products, but had seen some good feedback from people on RC Groups. Conversations with Hyperion (via email) made me feel very comfortable with the company. So I started working out what I wanted and ordered away!
When the new Magellan-E arrived from Icare, I wasn’t disappointed. It was nicely packed and no shipping damage. I could tell that a lot of engineering design effort had gone into keeping this plane light yet strong.
The new fuselage design is interesting. The body is made from a black and yellow tweed of carbon fiber and Kevlar that makes the plane stand out and look a little like a flying yellow jacket. Although this pattern looks sharp for the fuselage, I think straight carbon fiber or a solid color would set the canopy off even better. (That’s just a personal preference of course!) The nose of the Magellan-E is widened quite a bit making room for a nice-sized outrunner motor power plant, like my new Hyperion Z3025-06.
Fuselage = 120 grams
The two-piece wing is light and strong, but not overbuilt, using D tube construction and balsa rib bays in the center. The wings are very similar to the original Omega. Some of the covering on ribs and outside edges needed a little extra tacking down with an iron on low heat. The center joiner is made of steel which surprised me, but it is strong and doesn’t add too much weight. I have yet to feel the need to replace it with a Carbon Fiber rod. Someday I might “get around to it.”
This plane is a true ARF! Once I had a plan and all the components, I called my friend Devon over for a “build night.” This plane can be built by two guys in just six hours! (Not including radio programming my ROYAL evo 12, which didn’t really take very long.) We worked hard and we had good tools at our disposal. However, my shop is small and my friend hasn’t built many sailplanes before, but having another set of hands there was a lot of help. No doubt someone could do it faster, but I expect that 12-16 man-hours is a reasonable average time to build this plane.
From the start I thought flaps would be a nice addition; and after I got my plane, new versions of the wings have come out with a flaps option. This will be a welcome improvement for competitions. A nice feature of the wing construction is the wire tube already installed to guide the servo wire to the servo pocket. Because both the wing and the guide tube are semi-transparent, the builder can see the servo wire make its way through the tube as the wire is installed. Please note that this tube is not big enough for the servo connector to pass through, so the servo plug must be soldered on after the extensions are run out to the servo bay.
The wing is very thin, a mere 18mm’s, so I chose to use HITEC HS 5125 MG slim digital wing servos. They worked perfectly! I used a clevis on the servo arm and 4-40 all thread control rod with ball links on the control horn side. This makes a very positive, slop-free connection, a method I often use for my competition type planes.
I suggest using a control horn that mounts through the aileron and has a base plate on the backside that the screws attach to. There is a reason for my recommending this approach. What happened to me, for reasons I can’t determine, is that the control horn, mounted by embedding it into the aileron, failed during a final landing approach. The control horn pulled out of the fiberglass and foam aileron thus leaving me with only one aileron working and the elevator for control. I was in a banking turn that I could not pull out of. The limited control resulted in a major crash.
Next the aileron, I suggest using the simple aileron tape technique. This has worked well for me and seems easy to apply with two people working together. The servo cover is tall and has plenty of room to accommodate the servo and servo arm. Simply use three screws to mount them after lining up with the servo control arm. The wing attaches to the plane via a small metal pin in the front that inserts into a hole in the fuselage, then a single plastic screw in the wing behind the center spar bolts into the fuselage. There is a small channel molded into the center of the wing to allow the servo wires to exit down and out to the receiver. The result of the “D” wing design with carbon fiber and high density foam is a stiff, lightweight wing that performs excellently.
We can now examine the tail section. This plane comes as a V-tail, and one of the few challenges of building this plane is making the elevator control linkage. I made a yoke from one straight piece of 2-56 all-thread, then another with a large Z-bend piece attached to it. The two pieces were then put in a vice and wrapped with carbon fiber tow then CA glue applied. I used a plastic clevis on the servo side and ball and cap links on the control horn side. The ball and cap connections prevent binding from small changes in the control horn rotation as the pitch is changed during control action.
Among the coolest pieces of hardware that come with this plane are the elevator control horns. They are custom fiberglass control horns that can be CA’d straight to the elevator surfaces. They work nicely with the elevator and provide consistent control surface movement. To add some strength to the elevator, I made a little piece of 1/64” plywood and light glass and sandwiched it to the bottom of the V-tail. Although this construction adds some weight, it adds considerable strength to an area I felt was a little weak.
For the elevator servo I chose the HS-55, a proven and strong light-weight servo. Even after several flights this servo has served me well. Because the servo is mounted just under the V-tail, it will require a long extension wire. Due to this length, it is susceptible to RF problems so we have to make sure to have either plenty of twist to the servo extension or one of those RF filters for insurance. Also, it is important to have positive servo extension plug connections. There are several ways of doing this. I use plenty of black electrical tape. There are probably better methods and off-the-self solutions that will work as well.
In the future, I may consider figuring out a way to make the V-Tail control surfaces work independently for both rudder and elevator control from the V-tail. This would not be too difficult for an experienced builder to do.
What a quick, easy build! This is truly an ARF compared to most sailplanes. The results are well worth the effort, what a beautiful plane!
Electrical systems are very flexible and electric motors will try their best to work with whatever you throw at them. How to set up the power system efficiently is challenging for anyone. How to do it in the lightest possible setup using 7-10 round cells for possible competition applications is even harder. I started with my nice LMR Hyperion Z3025-06 and requested a 14 X 9 and 14 X 9.5 prop from Hyperion when I ordered it, as well as their 80 amp speed controller and their cool Emeter to analyze the system once I got it assembled.
The next things to consider were the batteries. For these I contacted the good folks at MaxAmps.com and we decided that the IB1400’s would deliver the best power for their weight and size. We also decided that for regular sport flying it would be KILLER to have 3S 4000mah Lipos so you could fly almost all day on one charge! These Lipos have a high burst rating of 64 amps that can deliver some serious power. It all sounded like the right combinations to do the job. My electrical instincts felt very comfortable with this setup.
Then came test flights using the 8 cell IB1400's, my Emeter readings gave the first signs that things were not going quite as well as expected. I ignored this at first because the plane, being so light, did launch and fly nicely. But soon I could tell it just wasn’t peaked. The Emeter showed that at static current draw was under expectations. I talked to some RC Groupers and they too seemed to think there was a problem. I had cycled the batteries 10 times but that didn’t help. So I talked to Maxamps.com about the batteries and they came up with some answers. It was the way I was charging my batteries. I was charging them at ½ C to 1C max which is what I’m accustomed to using for Nimh batteries. They suggested I charge these batteries at 3amps! So I did…Man, did that make a difference! You can see this on the data logged by the Emeter on my test stand.
When I put the power package into the test stand, I still wasn’t getting what I felt was max performance. The data also showed the batteries were sagging pretty hard thus losing voltage to the motor. This means fewer RPMs from the motor. I turned once again to the RCGroups threads and asked questions and showed my data logged test results. One person came up with an idea: maybe the plane is over propped as well? This was causing the motor to draw more current than the batteries could efficiently deliver. Now we expect some voltage sag, but if the voltage gets too low when the current is peaking, then you are losing energy to the motor. In this case, the problem is due to the batteries’ internal resistance. These batteries are super performers for their size, but they are not Sub C’s so here we must trade off weight for a little extra internal resistance. By propping down I was able to regain voltage and this translates into RPM’s from the motor. I actually gained thrust by propping down! That can be hard to accept but it is a measured fact!
Just like its predecessor, the Carbon D-Light, the Magellan is an excellent light lift thermal machine. I found her very predictable and silky smooth on the sticks. With the CG pushed back a little and the light weight Nihm 1400 batteries setup installed, she would indicate and work the smallest amount of thermal action.
You do not have a rudder available to coordinate your turns so spend some time dialing in your aileron differential. Also note that this setting will change a little depending on your “typical” thermal turning speed and bank angle. And if you switch back-in-forth from different weight batteries, you can expect that will have a little effect on it as well. The Magellan will become a joy to fly once your aileron differential is dialed in.
Using the MaxAmps.com 4000 Lipo batteries you do add some weight and that robs a little bit of the Magellans' light lift advantage. However, it’s so dang fun to watch this plane shoot up like a missile and you do gain altitude fast as we will see in the graphs below. Plus the added advantage that you get to rocket up time and time again with 4000 mah, that’s just awesome.
I have flown the Magellan on & off the slope. It can penetrate very well for a plane of it’s wing loading and can take some pretty hard flying. I have not pressed her into hard negative G’s and don’t suggest it, but have dove her down and pulled back on the sticks for some BIG loops and saw no signs of failure. So, if you have a reasonable landing site, you can slope the Magellan and have a little fun with it. But those wings will not take kindly to smacking into rocks, limbs, or other slope hazards at all.
As expected, Lipo's can greatly enhance your power performance but at a weight cost of 284 grams. However, some contest directors will not allow Lipo's in LMR events. As you can see from the data collected this plane is impressive with Lipo's powering her.
Here we look at the data with the 8 IB1400 Nimh's. I would choose these batteries if you are looking for a "light lift thermal day" competition LMR setup. This will give you a light weight edge over others using Sub-C's and capitalize on the plane's light airframe. This setup will allow you enough power (about 300 watts) to reach thermal heights quickly yet save weight to work light lift which this plane does so well.
I had some bad experiences with my pretty new plane. After just a few flights, the stock control horn pulled out of the aileron on landing approach. This caused, I felt at the time, a total right wing loss! When I looked at that mess of a wing on the ground, I could not see any way to put Humpty Dumpty together again. So I ordered a replacement wing from Icare. I asked them to rush the order as the annual Quiet Flyer Alpine Soaring Adventure was coming up soon and I wanted to show off my new plane. * Icare did everything possible to help me. In fact, they found some older wings in the inventory, and called to let me know we didn’t have to wait for the overseas shipment. The newer version has flaps as well as ailerons so I was hoping to get one of those, but it was just too slow in coming over the seas. I held out to the last moment then finally told them to send me one of the old stock ones.
The wing arrived and my friend Devin helped me get it ready for the trip. Well, as everyone knows, “Haste makes waste.” There we were at the lovely Hells Canyon rim anxious to maiden this excellent plane. So, without doing a glide test we waltzed up the rim, wiggled the control surfaces and “chucked it” into the canyon. It didn’t take long to realize that ailerons were reversed! STUPID!!! With all my years of flying how could I fall into that beginner mistake? I was out over that BIG drop-off, trying to maneuver with reversed control surfaces. It didn’t work for long! I screwed up on a turn and into the rocks she went. Once again, the wing was demolished. This time it was all my fault, for sure, and I was crushed.
After the second day of pouting, my good buddy Devin said, “Come on, Frank, we can fix it; let’s just do IT!” With that, we worked late into the night to figure out ways to reassemble that sweet little wing. And you know what…WE DID IT! It flew the next day. And very well, I might add. The pictures offer proof.
Now for a little insight as to how we fixed that demolished wing. On the D Tube sections we used 3mm carbon fiber rods inserted into the foam and foam safe, CA’d them into place, added Carbon fiber tape on the spar side, then wrapped a very light fiberglass bandage around the whole break. We discovered that since the ribs were butt jointed to the back of the “D” tube, most of them had just popped off without much damage so they were simply CA’d back in their proper location. The sub spar was CA’d together and then carbon fiber strip used to back it as well. This gave us a strong repair without adding too much weight and didn’t look too bad after we were done. We recovered the wing with some yellow covering scraps we brought with us on the trip for just such a problem.
Once we got the plane fixed, we decided it was best to give her a test glide which was a success, thank goodness! Then it was out to the canyon. This plane flies GREAT, it’s lightweight and very responsive. Climbs were strong and near vertical.
The Magellan E will be an excellent LMR plane as well as a nice thermal sport flyer with all the climb outs you could want on the Lipos. The Hyperion Z3025-06, backed with 3S Lipos, provided climb-out that's staggering, giving dead vertical missile like climb-outs.
It would not be my first choice for slope conditions, as it is so lightweight and the wings would very easily be damaged by rocks and such found on most slopes. Also, without flaps, the plane does require a long approach path. I have my ROYAL evo radio programmed for spoilerons (both ailerons go up) to limit this issue.
With its easy field setup, superb performance, and flexibility, this plane is quickly becoming part of my “frequent flyer” club.
|Nov 28, 2006, 07:17 AM|
Sunshine Coast, Australia
Joined Sep 2004
in Australia the Z3025-06 is a popular motor for our 7 cell LMR comp, which is a no-Lipo event. The hot setup is 7xGp2200 cells on the Hyperion 80 amp ESC with a 15 x 10 prop. This draws 100 amps and the motor and ESC are fine as long as motor runs are limited to less than 10 sec, which gives more than ample height! For really insane launch heights use a 14 x 9.5 prop and up to 30 second runs.
A 7 x GP2200 pack should be a similar weight to your 8 x IB1400 pack so that should maintain the flying qualities you are enjoying.
|Nov 28, 2006, 04:40 PM|
that's one of the tough calls on this project, keeping the power up and the round cells light. Sub C's are heavy, but have such nice power punch! The IB's were lighter, but more internal resistance. With the planes over alll design focused on light weight, I choose lightness over raw power. On other LMR planes, I think you are right to go with the GP2200's. the Z3025-06 is a ROCKING motor, as the test graphs show
|Dec 26, 2006, 01:34 PM|
After a bit of a hiatus, I got my Magellan flying this weekend. I went for a lightweight set-up, using a Razor 2500 motor, Maxon 4.4:1 gearbox, 10-6 Cam folder with a Jerzy spinner, CC25 esc, TP2100 3S pack, JR241s on the ailerons and 2 HS-55s for the V-tail. AUW is just over 27oz.
I maidened it on a local slope in about 2mph winds with some weak thermal lift thrown in. Performance was quite good, with a fairly wide speed range and predictable handling. There wasn’t much thermal activity, but it seemed to signal lift pretty well, and was able to core some small thermals. Rolls were a little slow, loops were uneventful – though it does loose energy quickly, and stall turns were very nice. Even ran a modified F3F style course and was able to get it wrapped up pretty well (for a lightweight 2M thermal ship). With the motor on, it climbs out at about 45 degrees and gets to altitude “quick enough.”
A couple build notes:
|Dec 26, 2006, 10:51 PM|
USA, GA, Marietta
Joined Oct 2000
Just a note.
For AMA LMR competition, it's now 8.4 nominal volts. That's 2S or 7 round cells, and you get 45 sec of motor run.
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