E-flite Eratix 3D FF

Mild or wild pilots wanted

By Ron Hull | [email protected] Photos by Ron Hull

As seen in the Summer 2023 issue of Park Pilot.

I was more excited than I probably should have been when I saw that E-flite was coming out with the Eratix 3D FF (Flat Foamy) airplane. I took a lot of flak from some of my friends for wanting this airplane as much as I did. After all, at first glance, it’s just a couple of  flat pieces of foam with the electronics and battery hanging off the side—but this airplane is much more than that when you take a closer look.

The Eratix has quickly become one of Ron’s favorite airplanes. It’s a capable aircraft that easily fits in most trunks without disassembly.

One of the biggest reasons I was drawn to the E-flite Eratix 3D FF is that it is a fairly inexpensive way to help me learn to fly 3D and other maneuvers that I’m  not yet proficient at flying. I’m a fairly competent pilot, but my goal for this year is to push myself to fly more often and to fly out of my comfort zone.

This airplane fits the bill on both of those points. For a flat foamy model, I think this is a good-looking airplane. Having something that is this easy to fly, this fun  to fly, and that fits in my trunk makes it an airplane that gets flown a lot. I’ve flown it more so far this year than any other airplane I own.

What’s in the Box?

If you already fly with a Spektrum transmitter, you can get the BNF (Bind-N-Fly) version of the Eratix, which comes with the airframe, a Spektrum Avian 15- amp brushless Smart ESC, a 2405-1200 Kv Spektrum Avian brushless outrunner motor, Spektrum A347 submicro digital servos, and a Spektrum AR630 receiver. Also included is all of the hardware needed to put it together, and all of the electronics are installed from the factory.

Spektrum’s BNF airplanes are some of the quickest to set up and get flying on the market. If you don’t fly with a Spektrum transmitter, or if you want to use a  different radio system, the PNP (Plug-N-Play) version comes with everything listed above except for the receiver, leaving the radio choice up to you.

Assembly:

By the time I finally made the trek to northern Illinois to go to my favorite hobby shop, Dynamic Balsa (or as we affectionately call it, “Brian’s Place”), I had missed the first shipment of BNF Eratix airplanes. Luckily, Brian still had the PNP version in stock and a separate receiver that I could  install myself.

The receivers that come with BNF airplanes have model-specific programming loaded onto them from the factory for the airplane they are installed in. If you  have your own compatible Spektrum receiver, you can head over to Spektrum’s website to download the program files and load them onto your receiver using the appropriate programming cable. This is what I had to do since the BNF Eratix was out of stock and I’m impatient.

The few extra steps I had to take to install the receiver didn’t add much complexity to the assembly. The airplane is well thought out and designed to go  together quickly and easily, and assembly was a breeze. I was impressed with the way the airplane bolted and snapped together, even though it’s flat foam.

The fuselage comes fully assembled out of the box, with the vertical stabilizer installed and the pushrod attached to the rudder. All of the control surfaces come hinged from the factory, and all of the control horns are installed. The horizontal stabilizer slides through the fuselage and is held in place by a couple of  screws. The carbon-fiber landing gear legs slide into a slot in the fuselage and lock into place with a satisfactory click so that you know they’re fully seated.

Wing-tip bumpers help protect the most vulnerable part of the airplane, and carbon-fiber reinforcements help strengthen the airframe.

The two wing halves slide over a square carbon-fiber spar, and they get screwed to the fuselage. Wing struts are installed with a screw on the fuselage and a  clevis on the wing. The side-force generators need to be installed so that the colors line up with the design on the wing. It took me a minute to figure that out, but because they just push on, it was easy to fix my mistake! The pushrods get installed on the horizontal stabilizer and each aileron.

The last thing to do is put the propeller on. The Eratix comes with a propeller saver, so the propeller is held on with an O-ring. This helps to lessen airframe damage if you have a propeller strike. Overall, assembly of this airplane was quick, easy, and only took about 10 minutes.

Setup:

After the Eratix was assembled, I spent some time setting the airplane up the way I wanted it and making sure everything was correct, especially since the  receiver didn’t come pre-programmed with the airplane. I fly with a Spektrum iX12 radio, so I was also able to download the transmitter setup file and a picture or the display. After I bound it, I checked that the control surfaces moved the right way, that the surface deflection was set to what was called for in the manual, and checked the exponential settings.

I used a three-position switch to change between SAFE mode, which limits pitch and bank, and AS3X mode, a gyro that works like shocks on your car to  smooth out the flight. I programmed the right knob to change the AS3X gains so that I could fiddle with it during flight. I also set up high and low rates on a  switch.

The last thing I did was program throttle reverse on the momentary button. I can’t really think of a reason for this airplane to need throttle reverse, other than  the fact that it can since it comes with an Avian ESC, but I wanted to try it out! It doesn’t back up very well in the grass, so this is a feature I might turn off on  this airplane.

Flights:

I went to our local flying field for the maiden flight. Even though E-flite recommends a 3S 600 mAh battery for the best performance, I already had a few of the  S 850 mAh Spektrum G2 Smart batteries on hand, so that’s what I used for my first flights of the Eratix.

I strapped one to the side of the airplane and plugged it in. I always check the CG (center of gravity) right before I take off on a maiden flight, and it balanced  well within the range of this battery. I decided to try a rolling takeoff since our field was cut nice and short. I turned the AS3X gains as low as they could go, ran  through a quick preflight check, and then taxied out on the runway.

The battery quickly fastens to the side of the fuselage for quick battery changes, and the propeller saver helps protect the airplane in the event of a propeller  strike.

I was surprised with how well it rolled through the grass because I’ve seen other small airplanes get their wheels caught and flip over at our field. I gave it  some throttle and it took off within about 20 feet. After I got some altitude, I started to raise the AS3X gains until they were set to where I wanted them. There  wasn’t a lot of wind, so the AS3X didn’t have to work too hard, but I could definitely tell a difference when it was switched on.

Hand launching is extremely easy with this airplane if your field has a less-than-ideal runway. The Eratix is a pleasure to fly, and the color scheme makes it easy to see in the air.

This is a pretty light airplane with a lot of flat surfaces, so you will notice the wind, but the AS3X does a really good job of smoothing out the flight.

I played around with SAFE mode. I put it in an upside-down spin, flipped it to SAFE, and it quickly reoriented itself. After a couple of laps, I switched it to high  rates to see what it could really do. The roll rate is phenomenal, high-alpha flight is simple, and there is plenty of rudder throw for knife-edge maneuvers.

The Eratix has plenty of control throws to go from mild to wild flight. High rates might be a little too advanced for a beginner pilot, but low rates tame this airplane a lot.

This is not a fast airplane, though. I was actually a little disappointed by its lack of top-end speed, but that is more than made up for by how well it flies. Landings are simple, but it’s easy to flip over after touching down in longer grass. After all, the wheels aren’t very big and there’s no wind blowing over the  levator from the motor.

The Eratix has plenty of power for hovering and unlimited vertical. The flowing lines and colors really caught Ron Hull’s attention.

I live in the country, and my biggest draw to this airplane was wanting something that I could use to practice flying. It’s really easy to throw a battery on it and  get some flights in during the week without having to worry about loading up the car to go to the field. It flies easy enough to where you don’t need a huge  area to fly in, so it’s wellsuited for schools or parks. If the grass isn’t cut short enough for a rolling takeoff, it’s really easy to underhand launch. It has plenty of  power.

Final Thoughts:

You can tell this airplane was well engineered to last for a long time. I have many flights on mine and there is no damage on it yet. There are carbon-fiber reinforcements throughout the airframe, and it even has plastic bumpers on the front corners of the wing halves to protect them from damage.

The Eratix is a fun airplane to fly, and it lets me try things that I wouldn’t be comfortable trying with an expensive airplane. Because it is flat foam, repairs are  generally quicker and easier than with a balsa model. I try not to use it, but having SAFE also adds to my peace of mind, knowing that if I lose orientation, the  push of a button will bring me back to level flight.

I’m not sure how long the foam wheel pants will last, but they’ve held on so far, even with some not-so-pretty landings in tall grass. If you’re looking for an  airplane that goes together quickly, is easy to fly, will help you learn new maneuvers, and won’t break the bank, the Eratix just might be for you!

SPECIFICATIONS: TYPE: Aerobatic, electric flflat foamy WINGSPAN: 34 inches LENGTH: 35.69 inches RADIO: Spektrum iX12 2.4 GHz transmitter; Spektrum AR630 receiver (included); four Spektrum A347 submicro digital servos (included) COMPONENTS NEEDED TO COMPLETE: Fourplus-channel DSM2/DSMX transmitter; 600 to 850 mAh 3S LiPo battery with IC2 or EC2 connector; charger MINIMAL FLYING AREA: Medium-size park POWER SYSTEM: 2405-1200 Kv Spektrum Avian brushless outrunner motor (included); 9 x 4.6 electric slow-flfly propeller (included); Spektrum Avian 15- amp brushless Smart ESC (included); 600 to 850 mAh 3S LiPo battery with IC2 or EC2 connector FLYINGWEIGHT: 13.1 ounces FLIGHT TIME: 5 to 8 minutes PRICE: $219.99 Smart BNF Basic; $199.99 Smart PNP

FEATURES: >> Easy to assemble >> Good size for transport; fifits in most trunks >> Wide flflight envelope, from mild to wild >> Capable of slow cruising, sport flflying, basic, and all-out 3D aerobatics >> Specially tuned brushless motor that’s factory installed and ready for use with popular 3S 600 to 850 mAh batteries