INTRODUCTION

Here is a new easy 3D quadcopter, the Eachine E20. This model allows to fly inverted by a simple clic. Easy 3D means you don’t need to invert control commands when the quad is upside down. Let’s have a quick tour of this E20.

BOX CONTENT

+ 1 x Eachine E20 (with a 1S 400mAh LiPo with micro-LOSI)
+ 1 x Transmitter (using 4xAAA batteries not included)
+ 1 x USB charging cable
+ 4 x Spare props (2 CW, 2 CCW)
+ 1 x Instruction manual (English)

OVERVIEW

The general design of the E20 is a kind of spider where prop guard can be seen as huge feet/landing gear. The first contact with the machine shows a recycled plastic relative hard and IMHO not enough flexible to absorbe hard crashes.

-Front view

Naturally, the E20 have props targetting the ground pushing the air but furtunatly, they are well protected by these large prop guards.

The weakest point IMHO is the jonction between the upper and lower canopy part. If crash hard perpendiculary, this zone will break especially with this regid plastic.

-Side view

-Rear view

Out of the box, there is a small door locking the battery compartement but after a simple manipulation, in general the door will pop out by itself. In practice, the battery fit well all the available room, so the doors is in practice pretty useless.

-Upper view

-Bottom view

Some strong LEDs, red for front and blue in rear.

-Weight

Less than 52g, pretty good when we know that some 8.5mmx20mm coreless motors are installed.

Props

The “core” of the 3D model: Some 60mm prop offering symetrical thrust capacity. With such props, no miracle, you can’t be as efficient as one direction prop. In practice, we can expect less thrust efficiency. As you can see when installed, the main motor shaft is relatively longer 2-3mm of free gap.

60mm props with 1mm shaft diameter

Motors

Classic 8.5mmx20mm coreless motors…. they are strong versus the total weight.

LiPo

A 400mAh 1S LiPo with micro-LOSI

Disassembling

On the upper PCB, a set of MOSFET, twice more since we need to fly inverted. A JF X40 reference is written… probably the real designer of the E20. Motors are directly soldered on PCB pads.

The RFchip is located front, probably a XN297. Unfortunatly, I was not able to bind any existing radio protocols.

Transmitter

A gamepad style transmitter. No LCD or shoulder button, only two tiny buttons. In practice, the left one is used to change to flip mode: between 360 & 180 degrees flips. The right button is to reset to default flip mode, here 180 degrees. In fact to invert the quad or to do a 360 flip,, you have to click the right control and after 1s, the quadcopter will flip of 180 degrees by itself (inverting sens of rotation of motors) or by 360 degrees. Two speed modes are available via the throttle trim buttons. In beginner mode, the pitch & roll rates are already touchy. In expert mode, the yaw rate become very fast, IMHO too fast to fly precisely in fast forward.

Not mentioned in the instruction manual, but it’s possible to calibrate accelero by pressing the left stic in lower right while the right stic pressed on the left. There is also an hidden headless mode but it can be applied only at take-off: press the left stick in lower left while the right stick in right direction.

No sign here but probably an XN297 (or a XN297L) in SOP16 packaging (see datasheet here: https://drive.google.com/file/d/0B3AKcbg1PFrnbHRXMzUzUUFmUFk/view?usp=sharing)

FIRST USAGE

The E20 is sporty even from beginner mode. In expert mode, the yaw rate is definitively too fast especially after a fast forward or a rapid uturn, the E20 becomes instalble a bit, loose some altitude. It’s even more true when fly inverted. The expert mode in fast forward mouvement need to be ultra precise with the ruddler command. The 3D mode is ultra easy … in fact, it’s like auto-flip… you will play with a dozen of time but since commands are not inverted, it will become fast boring. LEDs are well visible and flight duration pretty good, around 7min. THe control range offer a good 30-40m out of the box (of course can extented via antenna mod).
As expected a bit, after few crashes, the front right guard broke a bit in the weak point …. I also noticed that one side flight is less powerfull than the other one. You can loose 2-3m of altitude easily.

CONCLUSIONS

Well, I am not so impressed by the Eachine E20. It’s not a bad machine, but Easy 3D becomes very fast boring since no real flying skill Learning challenge behind: just press a button and voilà. The E20 is touchy in expert mode and the yaw rate requires to fly the E20 very precizly. I really appreciate its night flight capacity and relelatively good radio range but I feel the durability of the canopy is limited dur to this recycled pastic.

UNBOXING

PROS

+ Easy 3D
+ Nice design
+ Night fliyer
+ Hidden headless mode
+ 7min of flight duration

CONS

– Poor instruction manual
– No real interest of the easy 3D
– Too fast yaw rate in expert mode
– Underpowered/unstable when the E20 is nverted
– Recycled plastic/fragile prop guard
– YaP (Yet another Protocol)

RCgroups thread: http://www.rcgroups.com/forums/showthread.php?t=2645321

This quadcopter have been courtesy provided by Banggood in order to make a fair and not biased review. I would like to thank them for this attitude.
You can find it actually for 25USD at http://www.banggood.com/Eachine-E20-3D-Mini-Spider-Inverted-Flight-2_4G-4CH-6-Axis-LED-RC-Quadcopter-RTF-p-1034932.html