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Saturday, September 8, 2012

MXS Flight Test __ 64 Inches Of Awesome

 Having had Extras, Edges and Yaks in a multitude of sizes, one constant I have noticed it that as you go bigger the planes become smoother to fly, more precise, and they feel more solid and sure footed. Having until now  flown an MXS EXP only in a 48" span, I could only guess this would hold true of the 60" MXS, but this time it was surprising just how much more smooth, precise, solid and sure footed it is.
Right now my MXS has a lucky 13 flights on it. Four of those were the first day out when my eyes were giving me a lot of trouble, so it is hard to count those. The rest were yesterday and with each pack I would run through the plane my confidence would swell. I thought I knew what to expect from the MXS, but it has already far surpassed that.
This is by far the best flying plane I have ever owned. I will have to fly it back to back with the 60" Extra to get a clearer picture, but I think for my style of flying the big MXS rocks.
The difference Is in The Tips.
Again, this is another case where a review gets a little weird.  The MXS comes with beautifully made racing wingtips. They are really works of art, and they do make a substantial difference in how the airplane files. As such, this report will center on flying the plane with the tips installed, and the next report will be on flying the MXS without them.
The beautifully made racing wing tips offered their share of surprises. A fiberglas version of these come with the 48" MXS, but I didn't find those to affect the flight characteristics all that much. As such, I did not expect the bigger ones to do much either, but I could not have been more wrong.  On the 60" MXS, removing the tips turned it into a completely different airplane.
OK, color me surprised. I figured they were cute little cosmetic pieces, but they are really very functional. The wingtips dampen the roll rate, slow down snap rolls, tumbles, pop tops, and the plane is more reluctant to go into a knife edge (KE) spin. In this configuration, the 60" MXS was actually tamer than I was expecting it to be. It is more like a big, easy, floaty 3D trainer.
You can see in our first two videos how incredibly locked in the plane is, and how docile and predicatable it is.  For the first few flights this was a good thing because I really didn't need to wreck it. Being so stable allowed me to push it really hard without the fear it was going to get away from me, but the price is the MXS signature wildness has also been dampened a bit, though even like this, it is still a damm nice airplane and still very capable.
I did make one flight using the SFGs and no wing tips, and like this the 60" MXS was much more like it's smaller sibling.  The roll rate probably increased about 40%.... it was startling, though not uncomfortable. It was just a surprise that it made that much difference.  I could get a full two to two and a half turns on a pop top, snaps were more violent and crisp, and KE spins were much easier,  requiring less attention to entry and form. It just goes in real easy without a lot of fuss, and locks right in effortlessly, whereas with the wingtips in place it requires a lot more finesse.
OK, I don't want this to sound like it is a bad thing, because quite the opposite, it's not. The wingtips actually serve a very useful purpose, and that is taming the MXS down to the point that almost any intermediate sport pilot would find it easy to handle.  If you want a tamer MXS, put the tips on. If you want to go ballistic and fly a wild MXS, take them off.
Removing the tips makes the MXS into a much more aggressive performer, and I think that is eventually the way I will prefer to fly it. For now, though, I had already flown it with the tips so much that I figured this would be the best way to shoot the video, and next time out I can get used to it without the tips for a few flights and shoot some more. I think the differences will be very interesting. 



In general the big MXS is much like the small one, but in this configuration is is so smooth and forgiving that you could almost use it as a 3D trainer. It is surprisingly easy like this, even with the big throws I am running. The one thing that kept happening over and over was my being surprised at how gentle the plane is to fly.
But it's still pretty agile. As you can see in the videos, pitch authority is nearly as strong as on the little one. The one thing I would have liked more of on the 60" Extra EXP was pitch authority, and on the MXS it seems just about right to me. It will stand up real nice in a wall, and pop to nearly dead flat in a parachute. As you can see in the video, it also does a real nice elevator manuever, but you can also see it moving forward a bit too, so I am still probably a bit nose heavy.
Dialing It In
Once I can move the CG back maybe another 1/8" to 1/4", I think the agility will really come in and those elevator maneuvers will fall straight down. I'm still getting it dialed in, but I am also moving slowly and cautiously because this is a brand new design that I have no previous experience with.
So far the plane has responded exactly like I was expecting with every adjustment. That's the mark of a good design.... it responds predictably to sound engineering and set up work. It's the crappy designs that bite you when you go the wrong way on set up. A good plane will give you signs where you are going wrong, but won't freak and and spin into the ground if you miss the set up a little.
With this being such a comparatively large and expensive plane, plus the fact I love it so much, I am trying not to get too confident with it too quickly. The problem is that the plane is so good that this is becoming impossible and I am starting to think that with the 60" MXS I am invincible.


Testing The Torque 4016/500 Mk II

Abridged, corrected and finally, finished.

We've been flying the 60" Extra EXP powered by the Torque 4016/500 and a APC 15/7E propeller with really good results. Power was astounding and the only other thing I would have liked was a little more prop for better vectored thrust (and control) when doing 3D maneuvers. Recently we had the chance to test the new, improved Torque 4016/500 Mk II on a Zoar 16/8 propeller. Early results are extremely encouraging and I really like this motor.

Since this article was originally published, the motor has gone into production. The motor in my Extra EXP was one of the prototype models that I was sent for destruction testing. The testing failed and the motor didn't, and it is still happily chugging away in that plane. I have since acquired a production 4016/500 Mk II that I am flying in my Extreme Flight 64" MXS and I am quite pleased with that one too.

Opening the box ...
you can see it's still a Torque. The new motor has the same beautiful, shiny anodized finish as all the other Torque motors, with the satin black middle band. Turning the motor over by hand, it feels extremely smooth. You don't even need to fly this thing to know it's a top quality piece, just like all the other Torque motors.

All the needed hardware is there including two types of prop adapters and X mount. One hardware baggie has all the necessary mounting bolts and the shaft collar, and the other has matching female bullet connectors and the appropriate sized heat shrink tubing.

Pretty much everything you need to install the motor is here except for the airplane itself, and of course, the speed controller. Also included is Extreme Flight's excellent warranty and customer service.

Right away you will probably notice the shape of the motor is slightly different. The front of the motor can now has sculptured air vents and internal ducting to pull air into the motor and direct it out the back. You can only get so good of a look at it without taking the motor apart, and it is even more difficult to photograph, but there appear to be little turbine like vanes just inside the air intakes. Hyperion used to have something similar to this, but it was an external, bolt on unit that made the front of the motor really long. From what I can see, this 4016/500 Mk II is only 6mm longer than the 4016/500.
Below is a little closer shot of the motor and it's new cooling slots. As you can see, the motor still mounts right up to the existing bolt holes in the EXP firewall, so that much hasn't changed. What is different is that the new cooling duct work added 6mm to the length of the motor. You may or may not have to remount the cowling on your existing EXP, depending on how critical you are of your spinner gap, but for the first day I just flew it with the slightly larger gap, and I was the only one who noticed it. Later I plugged the holes in the wood mounting tabs with toothpicks and CA, re drilled and now it's perfect.

As always, my planes use Airboss Elite ESCs. For the 60" planes the unit of choice is the Airboss 80. Like with every Airboss ESC, all you have to do is plug it in and forget about it. All Airboss ESCs now come with a Deans plug pre-installed, so you don't even have to solder that on Anymore.

Like the smaller 45 amp Airboss, the Airboss 80 now runs the servos on 6 volts, which gives them greater speed and torque, and as we are now finding out, longer life. The Airboss' on board BEC is 4 amp, and will handle from 2 to 6 cells.

With this being a 6s project, I am happy enough because I don't have to run a separate BEC and it's associated rat's nest of extra wiring and extra solder joints that can fail. I hate complex things and Airboss keeps it simple.

The low voltage cut off is auto detect and the 4016/500 Mk II runs best with everything set at default. Again, this means that you just plug it in, and don't worry about soldering, extra wiring or programming ..... you simply fly it.

To me it makes sense to run Torque Motors and Airboss ESCs in the EXP series planes because they were designed to all work together as in integrated package. You just bolt on the motor, plug in the ESC, use the recommended prop and go fly it. You always get super smooth, cool running with outrageous power, and dead solid perfect reliability.

Remember that I am flying Thunder Power 6s 3850 65C Pro Power series packs, so I will probably be pulling a few more amps than those of you who are using 30 or 45C packs. As always, check your own amp draw. I have seen a 5 amp swing just by changing to an identical propeller, so don't always believe what other people are getting for amp draw on their set ups.

Note: I am now flying this plane with the battery moved all the way back against the wing tube.

I've been flying the 65C Pro Power packs for about a year and a half, and I have been very pleased with their performance. They give me big, consistant power for the whole battery run, and the reliability and long life are superb. I'm getting about 250 flights out of my 4s 2700 65C packs and I run them super hard in the Florida heat. Almost anyone else should be able to get 300 flights out of them.
With this in mind it made sense to use 65C Pro Powers on this project too. I went with 3850 mah, though I could have gotten away with 3300 just fine. The plane is still so light and floaty that you can't even feel the extra weight, but the extra capacity is really nice.
Overall, I could not be more pleased with the performance. In particular, the speed and the sound are especially gratifying.

These two are made for each other because the Extra EXP (as well as the MXS) loves to go fast and the 4016/500 Mk II loves to be run hard. You will see a lot of high speed passes in the videos, simply because the Extra and MXS are so good at it, and this motor is so damm fast. I routinely found myself running out of room on my slow rolls and having to climb out to miss the trees to the left of the field and the hill to the right. This was never a problem with my 48" EXPs, though those are really quick too. The Extra and MXS with the 4016/500 Mk II really move out and chew up the sky.

You can also see how much confidence I have in the motor and ESC's throttle response. Much like bigger planes fly smoother, I think the bigger motors also have a smoother throttle response, but that's just my observation. By comparision, the smaller motors seem to me to have a more spikey response, whereas the bigger motor seems easier to modulate, and easier to make smaller power adjustments with the throttle. You will hear a lot less throttle change in my hovers and harriers because the power system is so tractable and gives me such fine control over the power delivered.
I have run it super hard for 25 flights, looking for any weakness, and it's just not there. It's got buttery smooth, cool running, blistering speed, stump pulling grunt, and it seems indestructable, all hallmarks of the Torque brand.
The Sound
The first thing I noticed when flying was the sound. Of course, I have often commented on how sweet and smooth the Torques always sound, and while this one is indeed smooth and sweet, it has it's own very distinct and very, very different sound.
The new 4016/500 Mk II doesn't really sound like an electric airplane. It sounds more like a turbine. The motor doesn't scream. It goes whooooooosh! It's a very different sound and I fell in love with it right away.

This is some left over footage I posted with no additional sound, just so you can hear what this little gem sounds like.


The motor itself is very quiet, so I think at high speed it is the sound of the air being pulled through the motor that creates that whoosh. Yeah, that's for real. Crank up the videos and listen. This baby goes whooooooosh!
At slower speeds and during harrier, hover and such, when you work the throttle this motor still growls and let's you know the power is there, just like any other like a Torque. The difference is when you get the hammer down, drop the nose to build some speed and rip across the field in a slow or point roll.

The first day out we ran the motor on an Xoar 16/8E prop. I was ready to stop testing props and keep flying at that point because the performance well exceeded my expectations, but we also need to try some wood props and we'll get to that soon.

I found performance with the 16/8 was startling, and the motor ran reasonably cool. After a particularly hard flight  we checked the motor temp on the runway (before it had a chance to cool down) and we were getting only 128 degrees. This was on an 85 degree day, so clearly the new cooling vanes inside the motor are doing their job well.
At the end of the third day, with my timer set at 5:30, was flying the plane really hard, and coming down with usually 22.70 or so in the pack. This leaves a really good safety margin and the packs will live a lot longer if you don't run them down so low.


The 4015/500 Mk II is a big improvement all the way around. We had one of the very first units and were told to run it hard and try to blow it up. As you can see in the videos, we did run it really hard. There are several sections where I am doing repetitive full throttle slow and point rolls for up to 45 seconds duration, and the motor pulled hard the whole time. I was a little loathe to hammer the batteries that hard, but when you use top quality stuff like Extreme Flight and Thunder Power, you don't really expect to have any problems, and we didn't.

Considering how well as this motor has ran, especially in view of it's reliability, we will be moving up our plans to build a 60" Edge. I missed out on the first run of those because I ordered too late, and I have been kicking myself ever since. When they come back in stock, I am not missing out again.

Results were better than anticipated.
Paul Tibbets, Pilot of The Enola Gay