Doc Austin

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E Flite's Mini Ultra Stick was the industry darling of 2006 and 2007, and for good reason...a lot of good reasons, really. Hangar 9's Ultra Stick family has been around for awhile and they are popular, durable, well sorted, proven, terrific flying airplanes. With the incredible surge of electric aircraft sales, it was only natural that the Ultra Stick would show up in the park flier market.

For us, this is the perfect aircraft. It is an extremely well built ARF, meaning less work and more fun for me. With it's symmetrical airfoil, constant chord, constant thickness wing platform, it is extremely aerobatic and supremely forgiving. With the motor hung out in the breeze on the front of the plane, maintenance is very easy. You can easily get to everything on the airplane that will ever require service, but since it is vibration free electric powered, there isn't much to do but take the wing off about every month or so and make sure all the screws are tight. Well, that and we wipe ours off every so often just because we feel guilty for having so much fun with so little work. I also don't worry much when I'm flying mine because even if I vaporize it in a nasty crash, with $89.95, and three hours work I'm back in the air with a shiny new one.

The Mini Ultra Stick is truly the most carefree R/C aircraft I have ever owned.

You can get the Mini Ultra Stick from most hobby shops and mail order joints for $89.95, and I think that's an ultimate steal. It comes fully finished with very little to do, and the hardware package is comprehensively complete. If you have a radio and power system, $89.95 gets you every single thing you need to complete the project. Everything.

Of course, as modelers we can never leave good enough alone, and we all add our personal little touches and improvements here and there. Since you can download the manual, and since there have been countless construction articles on this plane, there is little point in doing another. What I'm going to do is show you what we have done that is different, the things we have done to make the plane better for us.


Remember, though, that you will now officially be a hot rodder, so you might be on your own if you snap a wing or blow something up. We haven't had any problems at all like this, but this is one intense aircraft.

The thing is also going to be a fire breathing dragon. If you aren't used to fast, agile airplanes, this is going to be a quantum leap forward and you'll want to fly carefully and use a little restraint until you get used to it.


Yeah, the title is a little misleading, and there are no secrets.

There is only one secret.

It might look like black magic to some of the new guys, but it all boils down to preparation and execution. You take the standard stuff off the shelf, screw it together right, and then go fly the living crap out of it.

I know. I know that sounds so simple that it just can't work, but it does. Besides, the E Flite stuff is so well thought out that you just take it out of the box and start abusing it. Most sport pilots can just use the E Flite set-up, go fly, and have wild success. You don't want to out think yourselves on this. What comes out of the box is more than good enough for most people.

In fact, if you just want a nice sport plane, buy the Mini Ultra Stick PNP, use my control throw set-up, and go fly it. It's a very nice plane, but not everyone is willing to settle for just nice.


However, you can almost always get something more out of a product if you know where to look. E Flite made this plane for the sport flier, not the wild man. In some ways the plane is over engineered so that it will hold up in the hands of those a little less proficient, but this just leaves us more room to really hammer on it.


I'm sure Quique could make a Mini Ultra Stick do a really nice 3D dance, but we ain't all Quiques, and the Mini Ultra Stick isn't really that kind of plane. It's a sport plane, though admittedly what we are building here is an insane sport plane. This is going to play a big part in the plane's set-up.

We are going to fly it fast and we are going to fly it slow, so we need a set-up that will work for both. Sure, you can use dual rates and such, but what I try to do with my setup is take all the variables out of it except for the two sticks on the transmitter. I don't want to have to worry about switches, mixing, flaps, or expo or anything. I just concentrate on flying the plane and doing that as best I can, rather than being distracted by a bunch of bells as whistles. Oh, bells and whistles are fine, but not when you are hanging it out right on the deck and needing to concentrate on keeping the airplane out of the ground.

However, I do run a slightly slower low rate for my ailerons to keep the roll rate under control at high speed, though I usually just leave it on high so I don't confuse myself. I set the elevator at 100% on high and low rate because nothing is worse than pulling out of a sharp dive with little altitude and realizing that you are on low elevator rates.

The first thing to do is to get the CG right on. With most semi and fully symmetrical airfoils, We've found that 31-33% of the chord back is usually really good. With enough control surface movement you can usually get a flat spin out of most planes with this balance, but with the CG any further back the plane loses some stability in the pitch mode. You can go a little further forward and the plane will be more stable, but remember that we want the thing to dance for us. We have to give up a little stability for that, but we also don't want to go too far back and make it evil. I've found that the best place to balance the Mini Ultra Stick is right on the trailing edge of the main spar, but I admit that I like my planes just a smidge tail heavy. I arrived at this by moving the battery back and forth until I hit the spot I liked. Eventually I added 1/8oz of lead to the tail by running a screw through it and into the tail skid, but more on that modification a little later on.

I didn't measure anything and I didn't use a lot of science. When the plane felt good I stopped moving the CG back. I would say for starters that you could balance the plane on the spar and work backward as your confidence in the plane grows. I still play with the CG from time to time, but I generally come right back to the same spot because it works so well.

At this point, since we want the plane to flat spin, the best solution is to keep adding throw until it does. You don't want much more that that because it will make the plane hard to control at high speed. After 2 years of tinkering with these planes, we have arrived at this:

Elevator
low rate: 1/2"
high rate: 1/2"

Ailerons
Low Rate: 1/4"
High Rate: 3/8"

Rudder
Low Rate: 2", but maybe go 1" until you are familiar with the plane
High Rate: 2"

What's funny is that this is the first time I have ever measured the throws. I always counted the holes on the servo arms and control horns that the push rods were set at. I always set my end point controls to 100%, though I have to add a little sometimes to get enough rudder.

This is just a starting point because you may have a different preference than I. We like the planes a little edgy, and the high rate set up puts it right there, but not so much that it's a handful. With this setup the plane flies almost the same on low rate as it does on high. You have good control at low speed, and at full speed it is still not to twitchy.

As far as exponential, we don't run any. This doesn't mean that expo is bad. It just means that, again, we like the planes a little edgy, and expo takes that away. We are flying expo on other planes and it's fine, but for these we run them linear, and that forces us to stay on top of them. My team is a bunch of old guys that learned and flew for years without expo, so we are just stubborn and don't want to change our ways. If you are running expo and like it, by all means keep running it. I recently set up a Mini Ultra Stick with 30% expo (-30% if you are lying Futaba) for a newly soloed student, and it was fine. The expo didn't effect anything except to make it smoother to fly.


The best thing about electrics is their brute, gut wrenching torque. Yeah, it's nice that they are quiet, and it's especially nice that they are clean, but it's the torque that makes them special and it's the torque makes them fly so well. Torque, if you have enough of it, allows you to get yourself into the most impossible of positions, and then power your way out. There have been many times that I have stalled the Mini Ultra Stick in a totally unrecoverable attitude, then hammered the power and blasted my way out.

Of course, then again, I have the insane E Flite 480 motor at my disposal.


Using an APC 12/6E or an APC 11/7E, the 480 pulls about 30-31 amps. The Thunder Power 3S 15C 2100 mah Li-po pack is rated at 31 amps continuous. In the broiling Florida summer the batteries tend to run a little hot if you fly plane hard (which we do), so this is pushing it. So far we have gotten away with it, but the batteries won't live forever given this kind of abuse.

We have of late switched over to the new Thunder Power 3S 2080 mah 20C Extreme series batteries that have a much higher discharge rate. Temperatures are significantly reduced and power throughout the entire run is about the same right up until the battery dumps. The old batteries tended to taper off a bit after a few minutes in the air, but the extreme series batteries have that edge almost all the way through the flight. These batteries were a really good investment, and with our set-up I don't think we are taxing them very much, so they should last a lot longer than what we've been running.

To harness all that power we are using the E Flite 40 amp ESC (speed controller). The best thing about an E Flite 40 is that you simply plug the thing in and it works. No fussing or messing around with programming. You just use it. This is especially nice for someone (like me) who doesn't implicitly understand how electrics works. At 40 amps, the ESC is much heavier duty than either the battery or motor, so this is a good safety margin, especially since the radio relies on the ESC for power. I don't care if the motor blows up as long as the radio doesn't go out and causes me to crash in the pits or something equally dangerous. However, this has never happened, or even come close.

Which brings us to.....


With these items we get absurd levels of performance and dead solid perfect reliability. I've got one 480 and 40 amp ESC combo that just logged it's 400th flight and it runs like the day it was new. These units have never received even a second worth of a break. I have tortured them from the word go, and it seems they are ready for another 400 flights.

I've never seen a 480 blow up. I've only seen one 40 amp ESC give up on a friend's plane, but it was brand new and that sort of stuff happens occasionally. Horizon swapped it right out with no questions asked. As much as I like E Flite, they aren't perfect all the time, so it's especially nice that they back their products so well.

Part of the reliability is attributable to the products being so good, but part of it is that they are now so under taxed in their new application. With this much power on tap, most pilots won't fly around with the throttle pegged, so the motor, battery and ESC sort of loaf along, much like you wouldn't need to use much of a 327 Chevy's power to push a Volkswagen around, but it's sure nice to have when you need it.


When the 480 motor came out, E Flite didn't have a plane in production that was made for it, so to some it (like me) was obvious that the motor was aimed at the hot rodders. We've been hanging huge motors on stick airplanes for 40 years now, so putting the big 480 on the Mini Ultra Stick didn't seem so outrageous at the time. Like happens any time you hack on a plane, some things don't fit quite right, and that's the case with the 480. However, it doesn't take much work to rectify that.

I have previously chronicled this process on another thread here, so we don't need to go through it all again. In the interest of conciseness, here's the link:

There is a wide myriad of equipment that you can use on the Mini Ultra Stick, but the industry standard servo for this size plane is the Hi-Tech HS55. They are cheap and astonishingly reliable, especially considering their micro size. For what we are doing, they are just about perfect. The HS55 fits the servo openings perfectly and they work perfectly.

We have recently had a minor rethink on this. With all the stress we are putting on all the equipment, the HS55 is beginning to get marginal. We haven't wasted a servo yet, but with the upcoming 4 cell tests we know that one day it's coming. The HS65 servo has a bunch more torque and carbonite gears, so for future Minis we will be using those instead. There is nothing wrong with the HS55 servo at all, but remember that we are building an insane airplane. If you plan on abusing this airplane as much as you can get away with, it only makes sense to use servos with as much torque and as strong of a gear set as you can wedge in there. I'll build up another one soon with HS65s and report on our progress.

One minor inconvenience is that you can't buy the Hi-Tech servo mounting screws separately. If you lose one you can't get another. It didn't take long for this to become a major annoyance, and now I use Dubro Allen head screws for everything on the airplane. The E Flite Allen driver fits them perfectly, so it's very convent to have one tool that works on every screw the airplane.


Aside from mounting the receiver with sticky sided Velcro, and routing the antenna out the back, all that's left of the radio installation is hooking up the push rods. For these I use the E Flite push rod EZ keepers that come with the plane. At first, the nitro guy in me didn't trust these dinky looking things, but over time I have learned they are stout enough to do the job and they are easy to adjust. Again, E Flite makes a Phillips head screwdriver that fits these screws perfectly, and it seems this is the only one that will. It's some sort of weird Japanese metric Phillips, but the E Flite driver grips it really good.

This is my personal plane set up with the Futaba 2.4 system. Your antennae routing will differ depending on the radio you choose, but with a 2.4's smaller antennae, it becomes a snap to run one wire straight back between the rudder servo and the inside of the fuselage side, and another straight out the other side into the airflow. Since this was my first 2.4, I didn't want to make it too fancy until I figured out how to make it work. After this project I will find a way to get the loose antennae back inside the plane, and I'll post the pictures here.


Using the standard Hi-Tech HS55 servo arms, I connect the elevator push rod to the third hole from the inside. This is just right for turning the plane hard at slow speed, but not so much that it's flighty at high speed. For the ailerons I use the second hole out at the servo (again with the standard HS55 servo arm), but that's a little too much for me. Moving it in a hole makes it too slow, so I have adapted my flying style to accommodate this, and I have the low rate dialed back just a bit (70%) if I really need to do something precise like a slow roll or consecutive rolls.

For the rudder, I use an E flite extended arm, and I go out a full four holes on that one to get the huge rudder movement needed to make this stable airplane do unstable things like snap roll and flat spin. This much control is also really useful for getting the plane to stall turn without actually stalling it.

Sometimes the pushrod will bind up a bit or not center properly because the pushrod will not line up with the servo as well. It wasn't designed to be that far out, so this is where your end point controls will help you out.

On all the control horns on the whole plane, I put the push rod in the middle hole. Running the push rod in the inner hole reduces mechanical stiffness to the control surface, and this can result in flutter. Over the years I have just gotten used to putting it in the middle and I'm too stubborn to change.

The aileron setup is so simple that there really isn't much to say about it, but here's what it looks like;


And, the inside of the plane:


A few things on the photo above are worth pointing out here:

(A): Mechanical Setup for rudder: Four holes out on an E Flite extended servo arm. You might want a little more or less, but this is what I use.

(B): Mechanical setup for elevator: Three holes out on an E Flite extended servo arm. Again, your preference might be different, but I find this suits my flying style just right.

(C): This is simply a zip tie I use to keep all the wires secure and out of the way under the battery tray. It keeps them from getting caught up in the servos and out of the critical cooling airflow.

(D): This is a strip of velcro I lay on the battery tray to keep the battery from sliding back and forth. You will still need a strap to hold the battery secure to the tray, but this extra piece just gives a little extra security.

(E): Putting the speed controller under the battery keeps it right in front of the lower cooling vent in the firewall, and thus, also right in the cooling airflow. It also keeps a lot of the wiring out of the cooling air that goes over the battery and it tidies up the battery compartment enough to make changing out the battery an easy task.

One thing to remember about stiky sided velcro, however, is that it really doesn't like to stick to bare wood. To get a really good bond, run some CA glue over the area it's going to attach to and let it soak in. Or smear a thin coat of epoxy over it. It's too fast and easy to just run some CA over the area, so that's what we do. You don't need to use a whole bottle.....just enough to seal the wood.

Now, make sure you let the CA dry first. If you put the velcro down while the CA isn't set, first, you will probably make a big mess, and second, the stuff will be glued on there forever and you'll rip the plane apart trying to remove it. Just soak the area with CA and go work on the wing or something until it dries.


Once the firewall is in and the motor is mounted, it's time to hook up the ESC. I have found the easiest way to do this is to slide the ESC under the battery tray in the front compartment. This keeps it out of the way of the battery and the connecting wires and makes it easier to get the battery in, out and hooked up or disconnected. After the ESC is in, I reach down with some large tweezers and plug the motor into the ESC.

I like to place a piece of sticky back velcro on the battery tray itself, and another to the battery. Remember to smear a little glue on the area so the sticky glue on the back adheres to the wood.


Worth pointing out on the above photo are;

(A): Another view of the speed controller located under the battery tray.

(B): With the ESC tucked away, sometimes the wiring to the battery might be a little short and difficult to plug in. I've added a few inches to that wire to give me a little slack to work with.

(C): The receiver is held in place with a piece of velcro. Nothing complicated here.

When using the supplied strap over the battery to retain it, the battery isn't going to go anywhere. It can't slide back, it can't slide forward, and it can't pop off the battery tray. You would probably have to fly the plane into a brick wall to dislodge the battery like this, but then you would have bigger problems than worrying about the battery coming loose.

This means there's one less thing to worry about when I should be concentrating on my flying instead. This is why we put so much effort into preparation.....and this is important: Concentrate on the flying the airplane instead of fretting that it's going to come apart.


While the insane E Flite 480 upgrade is far and away the biggest improvement we will make to the plane, there are other little touches that improve performance, reliability and serviceability.


Admittedly, the biggest downfall of the Mini Ultra Stick is it's tail skid and resulting wretched ground handling. On grass it's not so bad, but on a hard surface all taxing is going to do is frustrate you, but at least you will get to practice your ground loops.

Some guys have attached their own tail wheels, but I'm waiting for E Flite to design something that works as well as the rest of the plane. I don't see why they couldn't put a tail wheel on it that's similar to what they have done on the Ultra Stick 25E or the Mini Pulse, except the plane is already in production and they sell every one they can crank out anyway. They don't need to do it because we will buy the plane either way, but I think they would also sell every add-on unit they could make.

So, while I'm not real crazy about the tail skid, I have to find a way to live with it for now. The biggest structural weakness of the tail skid is that it's mounting studs stick into the bottom of the horizontal stabilizer and they are only about 1/4" deep. After a bit of rough use it can come loose, or even fall off altogether. While it isn't a catastrophic deal, this sort of thing makes me crazy, especially since it is so easy to fix. Once I get the horizontal stabilizer lined up and tightened down, I simply drill a hole right through the middle of the tail skid, through the stab, and into the plywood on the bottom of the fuselage. Then I put a Dubro self-tapping allen head screw in it.


A nice benefit of having this screw on the outside of the plane and so close to the rear is that it makes a nice and unobtrusive place to hang a 1/4oz or so of lead to balance the plane out. These planes amazingly come out very similar to each other in balance, so most of the ones I have set up balance at my preferred spot with either 1/8 or 1/4 oz of mag wheel weight.


I simply drill a hole in the lead, run the screw through it, and then put it back in. This secures the lead really well and it's on the outside where you can change it in a few seconds. It's also so far enough back on the airplane that it takes very little unwanted added weight to move the CG. I also like the fact that I don't have to cut a big hole in the plane.


I like to use an old trick from the nitro days on the landing gear. Instead of using the supplied steel allen bolts to hold the dural landing gear on, I replace them with 440 nylon bolts. In a bad landing the nylon bolts will shear off instead of ripping the landing gear blocks out.

At the end of this clip, you can see how the gear will just pop off when I make a bad landing. The plane bounced on me, and since I had stalled it so deep, it just crashed down on one wheel, wrenched the gear sideways, and snapped the bolts. It wasn't a big accident, but without the nylon bolts it probably would have pulled the bottom out of the plane.


If the Mini Ultra Stick has an Achilles' heel it's the landing gear block. Lots of guys make a bad landing and rip the thing right out. It can be fixed easy enough, but why go through all of that and have a patched up plane when you can replace a couple of 15 cent bolts and the problem disappears?

About one time in every hundred the gear will come back and wipe out the stab, but remember that a replacement stab is about $15 and a replacement fuselage is about $40. This doesn't even take into account how much work it is to set up a fuselage, and how little work it takes to just bolt a new stab on.

If you tend to make rough landings (or do lots of touch and goes) the bolts will eventually fatigue and snap off on their own, even without a bad landing. They are easy enough to replace, and I do that about every 50 flights because that seems to be close to their lifespan.


This modification works exceptionally well. You won't knock the gear off on anything less than a bad landing, but we have driven the planes straight into the ground at full throttle and have not pulled the landing gear block out. In fact, since we started using the nylon bolts, I have not seen a block come out at all.

Personally, I like the Dave Brown 2" diameter grooved sponge tires because they are a more dense than the originals, and this reduces bouncing if you hit a landing less than perfect.


They are firm, but they also absorb a little shock too. Actually, they seem like just the right compromise between firmness and chushyness. They are wide enough that they won't get stuck in anything less than tall grass or really deep dirt, and they also down go flat from the weight of the plane sitting on them while in the pits.


As noted before, we fly in Florida, which is a beautiful place for about 9 months out of the year, but in the summer the heat is absolutely brutal. It isn't unusual to see us out in 92-95 degree heat hammering on our Mini Ultra Sticks. Since we aren't smart enough to throttle back a bit when conditions dictate a Little restraint, our batteries tend to run a little hotter than we like. I don't think they get so hot that we damage them, but the cooler you keep a Li-po, the better it's going to perform and the longer lifespan it will have.

The Mini Ultra Stick has enough holes in the firewall for sufficient cooling under sane conditions, but the Florida wild men need a little more. We could open up the firewall a little, but that would weaken it. There also isn't another good area to cut an intake hole without sacrificing some strength, so the only place we could look at is the battery hatch.

A scoop would work really nice, except the drag could possibly pull the hatch off in flight. After a bit of tinkering we settled on a NACA duct. These produce good airflow with very little drag penalty. Since the hatch angles slightly upward at the rear, this also adds a little bit of ram effect, but not enough to rip the hatch off.


As you can see in the photo, we plugged the forward lightening hole in the hatch (which actually strengthens the hatch) and cut a nice triangle out for the vent.


Then, We built up some sides for the piece I just cut out. We didn't use a lot of science here. We just eyeballed it and cut one side. after trial fitting to make sure we had what we wanted, we simply cut out another piece just like it, and glued it together, and painted it with black dope.


Once the dope dried, it was a simple matter to just glue it on the bottom. Shazam! High Tech aeromolecular management system!

We have tried to cover the finished hatch and vent work with ultracote before, and it's too much work, so now we cover the hatch first, paint the vent work with black dope, and then glue it on the bottom.


Also visible in the photo (but with photoshopped outline in black) is a clear plastic wicker we glued on to direct a little more air into the vent. Our adviser on this was Gary Wheeler, who is the inventor of the vortex generator, and a world renowned aerodynamics genius. He suggested that the wicker was a little on the crude side, but a small one would greatly increase the ram effect with a small drag penalty. Since the duct itself wasn't perfect, a lot of air was spilling over the top instead of being pulled in by the low pressure effect that a properly shaped NACA duct would generate. The wicker isn't very big, but it recaptures much of the air that's spilling over the top, and it sort of jams it in there. At first the ductwork gave us a modest amount of cooling, but with the wicker we got the results we were looking for in the beginning, so thanks, Gary!

It's not a perfectly shaped NACA duct because we aren't engineers or master builders. Our duct is rather crude compared to the way NACA ducts are used on real aircraft or race cars, but it works....just not quite as efficiently. In the future we may build a perfect one and then make a mould so we can vacu-form them, but that's too much work and what we have does the job.

Again, there was no need to out think or over engineer here ourselves. This is a simple, effective solution. The batteries don't come out of the plane with ice sickles hanging off them, but they do run noticeably cooler than before.


I have previous chronicled this process on this thread another thread, and here it's laid out a with a little more detail.


Pay tribute to our brothers and sisters who are far from home protecting us from harm.


Of course, I'm guessing that the Mini Pulse tail wheel assembly weighs about 1/8 to 1/4 of an oz. A Mark II version of the Mini Ultra Stick set up with 480 motor and steerable tail wheel would probably balance just about right. They've sold enough first generation Mini Ultra Sticks, so it's time for a new one, preferable in a cool new color scheme. They don't need to put much thought into this either because the Ultra Stick 25E scheme is already worked out and it looks terrific. They could graft that one on fairly easily, but it would need a few American flags on it to get the killer effect.

If E Flite made a Mark II version with optional firewall drilled for 480 motor, a steerable tail wheel, and in a new color scheme, I would buy three of them right off the bat.


Which is exactly what we have created here..........a raging little monster of an airplane. However, it is still just an airplane, so you fly it like one. Everything is the same as before, except now you have so much brutal reserve power on tap that you can turn it into an extraordinary advantage. The extra power is what takes the Mini Ultra Stick from nice sport plane to insane sport plane.


We are going to concentrate pretty heavily on talking about power, because that's the biggest improvement we have made. Not only that, but we have absurdly raised the power to weight ratio of the Mini Ultra Stick to the point that it is almost a completely different airplane.

Once I get my students to where they can fly a rectangle in both directions, I teach them stalls with particular empathizes on using the power to get going again. I teach them that when you are landing or flying around at anything close to a stall that the power is their most important control. On the buddy cord I will keep my throttle at full, so if I have to take it the plane will instantly go to full throttle. This technique has saved a whole bunch of planes. Without belaboring the point too much, the power is your best friend, even if you have too much. Once you learn to deal with it and aren't afraid of it, you won't ever have a more useful tool.

The first thing you will learn to do is hammer the throttle when you get into trouble. We routinely stall the plane very, very deep, and low to the ground..........and then club the stick forward and blast away. This shows up most in snapping maneuvers where the plane will come to almost a complete stop. At this point it isn't flying, so you had better do something. Putting the nose down to get flying speed doesn't work very well when you don't have any altitude to play with, so all that's left is unleashing that good old American brute force we hung off the nose. It's not an easy thing to do because early in basic training we learned that any time you get into trouble to slow the plane down so you can deal with it. At least that's what a lot of us were taught, but that won't help you when you are already stalled.

You just gotta get over it and learn to use the power to fight your way out of it. Sometimes this will backfire and you will plant the thing wide open, and with grand spectacle, into the ground, but at least you won't have to worry about rebuilding it.


The only time this has happened to me was when I was already way too deep into an unrecoverable position, so it really didn't hurt anything other than to make the inevitable crash worse.

Much, much, much more often than not, though, the power will pull the plane out. I think it's better to pour the coals to it and drive it into the ground trying to save it than it is to throttle back and try to minimize damage. If you have enough power, never give up on the plane until it stops bouncing. I don't think it's such a bad deal to have the power stick one in every so often if it saves 1,000 other planes.

You can use the power to keep the speed, and thus, control on your side. With heavier nitro planes you have to watch your speed and never get behind the power curve, meaning you can never go so slow that power won't get you flying again before you fall out of the air. With an electric's absurd power-to-weight ratio, and instant gut-wrenching torque,there really is no getting behind the power curve because it no longer exists.

Or, if that is too much to digest, just remember one thing: Hammer it and go.


This extra grunt is also very useful for pulling the plane through maneuvers. For example, I will pull the throttle back just before a snap roll, and right as she goes in I will peg the stick. The torque will actually pull the airplane tighter into the snap, and she will tumble much more violently because she won't be slowing down from the drag. This also keeps the plane from coming out of it too slow to make an instant recovery, so you can snap roll the plane at a ridiculously low altitude and have total control of it when it comes out. You can actually accelerate out of a snap roll.


For some reason I haven't figured out yet, the Mini likes an outside snap better than it does an inside. If you hit it just right, the plane will nose straight up, dance a turn or two on it's prop, l and then stall turn and come right back to you. I think there are one or two of those on the video, and while I've made other planes do it, none have done it as consistently and predicable as the Mini Ultra Stick, Ultra Stick 25E and the Pulse and Mini Pulse XT46.

You can do 1 1/2 outside snap rolls very low to the ground and then flare it out and land it. The airplane is so stable and predictable that we will try just about anything. I've done several of those, and even surprised myself once or twice that I actually got away with it. There isn't one on the video because it was windy that day and I wasn't all that anxious to vaporize a plane in front of millions on the internet. It's bad enough when my buddies at the field see me waste a plane and remind me about it every day for a month. I'm guessing the lifespan of internet needling over a crash is probably longer than my own.

But, don't do this unless you want to see if the plane blows up. We did this when no one was around because we didn't know what was going to happen. Unbelievably, the plane survived it, but again, don't try this at home:

We haven't gotten a Mini to inverted flat spin yet because we have been so happy with the rest of it's performance that we didn't want to change anything, but it will spin like a top upright. Again, everything is in the set-up, and if you've got enough rudder and a rearward CG, it will drop into a flat spin quite easily. Simply stall the plane into a spin, and once it gets going, center the ailerons. It will flatten out quite nicely like that, but if you let her go around a couple of turns and then slam in full down, she will really start whipping around. Eventually you will learn to use up and down elevator, and cross aileron control to either speed up or slow down the spin.


To get out of the flat spin, just release the controls, and she will turn a couple of times and come out. Then you just hit the power and start flying again. If you get her buried really deep you may have to use reverse rudder to get her to stop turning, but we have never actually gotten a Mini or a 25E stuck in a flat spin where it took more than a few turns to get out. The plane will flat spin nice and come out easily, but give yourself some room the first few times you try it.


With the CG set at near optimum the Mini does a really nice, tight stall turn, but it demands a slightly different technique than most planes. You have to slow the plane to just about nothing or it will fly right through the maneuver, and then it isn't really a stall turn. By the time you are going that slow the rudder isn't very effective, so it needs a little blast of power to get air going over it and get it working again. Lots of planes are like this, but few of them will turn around and drop back down right through their own turbulence like a Mini Ultra Stick. With as much rudder movement as I am running in my set-up, the plane will try to roll in the direction the rudder is turned, so a little cross aileron control keeps the wings level. It's not particularly hard to do, but it does take a little practice. When you get it right, however, you can do stall turns stupidly low to the ground because the plane is so predictable in it's behavior. And again, if it goes wrong, you know what to do, right?

One thing to be careful of with all this rudder movement and power is to be careful at low speed/low altitude. Once I was stall turning the plane really low, and I almost stalled it completely. I simply gave it a big blast of power to yank the tail around, but it was too much, and with all that rudder movement the plane dropped right into a flat spin all by herself. Well, actually, I made the plane do it, but it wasn't on purpose. Again, with no time to think about what to do, I pegged the go stick, she straightened out, and we flew away. Saved by brute force.....yet again.


The Mini Ultra Stick only goes about 80mph (my estimate) with the 480 motor compared to a healthy 40 sized nitro plane at near 100. The Mini is so much smaller that it looks faster anyway, but the startling difference is that in a drag race the Mini dusts the nitro plane off like Corvette against a Yugo. When I jump back and forth between my Mini Ultra stick and Pulse XT nitro, the biggest difference is in the acceleration. Sure, the big nitro job is faster, but that speed differential is nowhere near as dramatic as the edge the Mini holds accelerating out of a stall or other slow speed maneuver. With the nitro plane you have to lead the plane with the power, and maintain your momentum (airspeed), because you have to wait for the engine to spool up and get into the power band. The electric Mini, however, is always in the power band, and I swear it will accelerate from 0-80 in about a second.

Acceleration? We have measured the take off roll of a 480 powered Mini Ultra Stick on pavement ......18 inches.


One concern with adding a larger motor and batteries is what happens to the wing loading. Honestly, I have never weighed the 480 Mini Ultra Stick because it doesn't matter. The plane performs well with the extra weight. It still slows down really nice and doesn't exhibit any sort of bad slow speed tendencies.

I've flown a few Mini Ultra Stick PNPs with the 450 motor and lighter 1320mah battery, and they don't seen to fly any lighter than the heavier 480, while seeming anemic in the power department. If anything, the extra few ounces come in really handy on those 15mph wind days because it helps the plane penetrate better and the wind won't toss it around as much. Actually, we will still be flying our Minis long after some of the nitro guys have packed up because of the wind. We have flown in 25mph gusts, and while it wasn't much fun, it can be done.

Yes, with the lighter 450 power package you can putter around a little slower than you can with the heavier 480 set-up, but which one do you think is easier to get out of a stall or other bad situation? As my flying buddy, Rich, says, "There's no replacement for displacement."


I wish I could be the fly on the wall at E Flite when the president reads this and sees I'm calling his product a "beater," but it's true. The plane is so durable that it can get completely ragged out and look like it's ready for the trash can long before it's actually worn out.

For beat ability, I've never seen anything that can touch the Mini Ultra Stick for every day service and fly ability. It is clean and quiet, and requires embarrassingly little maintenance. You charge it up, throw it in the back seat of the car, fly the crap out of it, charge it up.......repeat as necessary. You can take it out day after day after day and almost never even have to take the wing off of it. Charging batteries is about the only maintenance I ever do.

Again, and worth repeating, is that the Mini Ultra Stick is truly the most carefree R/C aircraft I have ever owned.........ever, and that goes back longer than this old guy cares to admit. Because of this, I will always have at least one primary Mini Ultra Stick, a ready-to-fly backup Mini, and a kit in the closet.

Of course, setting one set up with all the right tweeks takes a little more work, but in the end it is more than worth it because the performance and enjoyment, goes right off the scale.

And, I know Joe would be proud, as I will forever be of him.

Denjones

OH MY GOD. Thanks so much. After seeing your videos, I want my setup just as you have yours. Thanks so much for the valuable lessons learned and the time you spent putting this presentation together.

Bad_Daddy

This IS a really great post! Thanks Doc!
It should be turned into a sticky or a blog or something so it doesn't get lost with all the other great info on this Forum.

cwrr5

My Feedback: (32)

Nicely done! [sm=thumbs_up.gif]

Andrew86

Perfectly executed! I can't wait to read 'The Secrets of the Mini Pulse XT' when you guys finish it, very informative and a few fantastic tips, I wouldn't be surprised if MUS sales surge after this write-up.

netdudeuk

Here's some more interesting info. It will fly ok with a £7.99 BP-21 / 2408-21T bell motor. Not fast but with the usual 8x4 GWS HD the climb rate was pretty good. It's all I had to hand and it it flew very well. More interesting is that I cracked my LE (too easily) and thought that I may as well see if it would fly with the wing from an old Firebird Commander - about 40" and 2/3 of the stock chord. Four rubbber bands looped round the landing gear and it was in the air within a couple or three metres ! I didn't like the rudder only configuration but it did fly ok and the glide in for landing was very smooth and I did two perfect landings before deciding I'd not risk it again with that wing

kryptonite

Wow, excellent article, Doc! I'm always impressed with your detailed reviews and this one is no exception - great job! Like you, I'm a great fan of the MUS and heartily agree that the Park 480 is a terrific match for it. Your write on the cooling mod cannot be more timely.
Just this past weekend - it hit 90F in NJ and I was flying my 480 powered MUS as usual - which is always a welcome diversion from my other noisy glow birds. There was little or no wind - so I increased the throws and was practicing hovering with the light little stick. The plane is so light that even with a 11x7 APC-E, it hovers easily with only half throttle. About 6 minutes in, the motor cut out - which was strange as I know I won't hit LVC until at least 15 minutes. As with all dead-sticks with the MUS, gliding it in was really easy. On the ground, the motor came back and I realized that it was a thermal cutoff - a first time for me.

The E-Flite 40A V2 ESC was so hot that the black PVC covering over the FETs has completely melted off! It works fine when cool, so I'm going to continue to use it -sans covering. I had mounted it on the side of the bulkhead next to the battery. Apparently, this position does not provide adequate cooling. I was thinking of mounting it in the exterior of the plane on the underside of the bulkhead. Now your article on the air scoop has me wondering if I should do it your way - it certainly looks more clean. You mounted your ESC just under the battery tray - don't you think that the battery obstructs quite a bit of airflow over the ESC?

Doc Austin

Man, I'de be afraid to use that thing again. If it overheated the BEC, that could end up failing and then you'de have a real mess.

The biggest cooling hole on the airplane is at the bottom of the firewall, so that's where we put the ESC. Once the air goes over the esc, it has no choice than to go up through the slots and past the battery. In this positiojn we have never had an ESC problem. I put 200 flights on one like that, and then another 200 in the Mini Pulse. Right nowm, that ESC has about 10 flights in my new Mini Pulse. It will probably run forever.

I've seen people do that, but if you crash the airplane on it's belly you could damage the ESC. Not only that, if you knock the gear off on pavement, the ESC is going to go sliding down the asphault with the plane on top of it. That, and i don't like the way it looks.


I am rather obsessive about keeping tghings tidy.

No. The bottom hole on the firewall jams the air under the battery tray and right back over the ESC.

kryptonite

I think you're right, Doc. Those FETs might be damaged already by the heat. The BEC was fine though - I was able to land my plane.

This is my second E-Flite 40A ESC, the first one died on the maiden - also a sudden loss of power, but the BEC was ok, thankfully, and I can still land the plane. My LHS promptly replaced it.

I'll try that position next. Funny thing is that when I had it mounted on the side - I have had over a hundred flights - never a problem. It was barely warm when I opened the hatch to replace the batteries. That last time the ESC was blistering hot. It might be that it developed a problem. I have good results with Castle Creations Phoenix ESCs. I think I'll replace it with one of those. The Phoenix has some nice programmable features like LVC voltages which the E-Flite lacks.

Very true - my present R/C fied is grass - but the MUS is so versatile that I might want to try flying off the hardened courts at certain recreational facilities - and a hard landing might rip off more than just the nylon-bolt supported landing gears :-(

windshadow

nice review. I have the 25e ultra stick . Something I did wich realy works on saving the nose on a front end crash was to add a piec of 1/8 ply over the existing piec I made it identical as far as the air holes and engine mount holes, I made it just large enough to go all the way to the ends of the frame and then glued it over the old one on, it transfers the force over the hole fuseloge on impack. I have only had one chash since then and it was a hard one, the crash was hard enough to break off the prop at both ends. I did a straight in nose dive while trying to land in the wind. the plane flipped over I tried to power out but just flipped over straight into the dirt. I put on a new prop and was back flying in about 10 min just thought this would help. take care bill.

dlcrashrc

Could you use an e-flite park 400 brushless in the mini stick if all u plan to do is fly and not do all these amazing 3-d manuvers I have complete drivline package 400 brush less , 36 amp esc and a 11.1 volt 2350 Mah LiPo ready to go and trying to get my hands on one of these little beautys funds wont allow for the recommended 450 outrunner so i wondered if a 400 outrunner would be ok if all im going to do is fly not stunt or trick fly. new to electric and i understand i might be underpoering the plane a little bit (or alot im not sure PLZ HELP). Funds Are the main thing holding me back and i already have this driveline package. Any suggestions would be greatly appreciated. I might not see it in forum so if you would plz send me an im to reply could really use the help i do not want to put her together this way and watch her fall from the sky, PLZ remmember just flying no tricks or stunts PLZ HELP?

A very confused and unsure
dlcrashrc

Xpress

My eyes just melted...........FROM THE SPECTACULAR EYE CANDY! LOL. Now I have to get one, but I was wondering what ESC you were using with the 480, since I didn't see any mention of it. And I'm still confused on what to get, the PNP, and upgrade the power system, or just buy the ARF, and put my own gear in it?

Fliprob17

To be 100% happy with the plane, and if you are already thinking about a bigger power system, go with the ARF kit. As for the ESC, a 35amp or 40amp should do the trick.

Doc Austin

To harness all that power we are using the E Flite 40 amp ESC (speed controller). The best thing about an E Flite 40 is that you simply plug the thing in and it works. No fussing or messing around with programming. You just use it. This is especially nice for someone (like me) who doesn't implicitly understand how electrics works. At 40 amps, the ESC is much heavier duty than either the battery or motor, so this is a good safety margin, especially since the radio relies on the ESC for power. I don't care if the motor blows up as long as the radio doesn't go out and causes me to crash in the pits or something equally dangerous. However, this has never happened, or even come close.

Xpress

Ok, I have a brand of ESC that I'll use for the 480, if I get the MUS. I've used X-tras 45 amp ESC before, and it stayed a bit warm, but the battery never got warm at all, and I was using it with a multiplex 480 geared motor.

sgf323

Doc, do your MUS's exhibit any roll when using the rudder?

Mine rolls quite a bit when I use rudder, especially in 2" high rates. I usually don't use the rudder much at all but sometimes when I want to do some flat turns I use rudder and manually feed in opposite aileron to keep an almost flat attitude which results in a nice smooth flat turn. Do you use any Rudder-to-Aileron mixing?

Doc Austin

Yes. So much of the rudder area is above the thrust line that it's goi9ng to roll couple. Just about any stick type model has really bad roll coupling because of this. In the 80s we built out own that had the stasb moved up and the rudder externded down to the bottom of the fuse, and they still coupled but it was much better.

No. We just fly around it. For what you're doing, it might be better to has less rudder movement.

We were going to modify the vertical and Horozontal stabilizers to eliminate as much roll coupling as we could, but we ran out of time.

sgf323

Thanks for explaining for the reason that the roll coupling exists. I tried a bit of mixing on a switch but didn't like it so removed it.

sgf323

I did 4 batteries today although more than 4 flights. I spent the first 3 batteries going up then landing while trying to get the mixes just right for knife edge flight using only the rudder.

After around a dozen flights I finally have it set to Knife Edge! I had to mix in some opposite aileron and a bit of down elevator. Now I can just roll on the side and knife edge perfectly straight.

I lose altitude relatively quickly when doing it though despite the fact that the nose is pointing upward a fair amount. I'm using a Park 450 and 10x8 prop, would a prop with less speed and more thrust give it a better chance of keeping altitude? I'm considering trying a 11 x 3.8 just to see what it would do.

jg4660

My Feedback: (1)

This is a very old post but about the best I’ve ever seen on any airplane. I just acquired a MUS and this info is fantastic. I wish I came across it before my maiden flight. I set the CG per the manual and it was all I could do to fly 2 circuits and get it back on the ground. The CG in the manual is VERY tail heavy. I’ll be back in the air following this info soon.