Eachine Racer 250

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Racer 250 is a UAV developed by the Chinese company Eachine.
Eachine Racer 250

Features

Item name: Racer 250
Main wing length: 140mm
Size: 220x233x50
Weight: 400g (without battery)
ANTENNA: RP-SMA Male RHCP
Headlight LED: white 3W
Camera: 1000TVL, support for HD night, camera angle is adjustable
Brushless motor: 2204 2300KV
Brushless ESC: Simonk 12A
Flight controller: CC3D
Lipo battery: 11.1V 1500mAh 25C 3S
Transmitter: 600mw 5.8G 32CH built in OSD
Receiver: integrated 6 channel (not included)
Remote control: 2.4G 6 channel (not included)
Flight time: 10-14 mins
Working temperature: -10°C to +40°C

Package Included

  • V3 Almost-Ready To-Fly Quadcopter
    • 1 x Eachine Racer 250 FPV Drone
    • 1 x CC3D Flight controller with Flexi port and Main port
    • 4 x Simonk 12A ESC
    • 2 x CW 2204 2300KV motor
    • 2 x CCW 2204 2300KV motor
    • 2 x black CW propeller
    • 2 x black CCW propeller
    • 2 x white CW propeller
    • 2 x white CCW propeller
    • 1 x mushroom antenna
    • 1 x B3AC balance charger
    • 1 x 11.1V 1500mAh 25C 3S battery
    • 1 x tail light LED colorized
    • 2 x headlight LED white 3W
    • 1 x 1000TVL camera
    • 1 x 600MW 5.8G 32CH transmitter built in OSD
    • 1 x remote control strap


  • V4 - Ready To Fly FPV Quadcopter kit
    • 1 x Eachine Racer 250 FPV Drone
    • 1 x Eachine I6 2.4G Transmitter
    • 1 x Eachine I6 2.4G Receiver
    • 1 x 7 inch 5.8G 32CH monitor
    • 1 x monitor holder
    • 1 x CC3D Flight controller with Flexi port and Main port
    • 4 x Simonk 12A ESC
    • 2 x CW 2204 2300KV motor
    • 2 x CCW 2204 2300KV motor
    • 2 x black DTI 5030 CW propeller
    • 2 x black DTI 5030 CCW propeller
    • 2 x white DTI 5030 CW propeller
    • 2 x white DTI 5030 CCW propeller
    • 1 x mushroom antenna
    • 1 x rubber whip antenna
    • 1 x B3AC balance charger
    • 2 x 11.1V 1500mAh 25C 3S battery
    • 1 x Velcro battery strap
    • 4 x AA NiMH batteries
    • 1 x tail light LED colorized
    • 2 x headlight LED white 3W
    • 1 x 1000TVL camera
    • 1 x 600MW 5.8G 32CH transmitter built in OSD
    • 1 x remote control strap
    • 1 x prop nut wrench
    • 3 x hex wrenches

Versions

Version 1 
CC3D Board without explicit support for 4S batteries - with wide LED bar
Version 2 
CC3D Board with added Flexi port and support for 4S batteries - with wide LED bar
Version 3 
CC3D Board with added Flexi port and support for 4S batteries and ability to change color of rear (8cm) LED light bar
Version 4 
CC3D Board with added Flexi port and support for 4S batteries and ability to change color of rear (8cm) LED light bar and surface mounted ESC capacitors
Version 5 
As per version 4, but now ships without center battery tray plate. Latest version (Aug 2016) has capacitors at the esc in the heatshrink and not on the board anymore.

Getting Started

[1]

  1. Connect your receiver according to the #PWM Receiver Connections section below. Or prepare your receiver according to the #PPM Receiver Connections section below.
  2. Charge the lipo battery.
  3. Download OpenPilot GCS to your computer.
  4. Connect your flight controller to your computer via mini usb cable (not included).
  5. Have your transmitter, lipo, and quad handy.
  6. Complete the vehicle setup wizard to calibrate your escs and configure the flight controller (DO NOT HAVE YOUR PROPS INSTALLED FOR THIS!!!)
  7. Click input on the left (transmitter icon). Setup your binding procedure and flight modes.
  8. Put on props (front left and rear right motors use CW (clockwise) propellers; front right and rear left motors use CCW (counter clockwise) propellers).
  9. Setup completed and ready for flight.
Eachine Racer 250 Manual

Setting Failsafe

Set failsafe in Flight Controller

Openpilot GCS failsafe setup https://www.youtube.com/watch?v=wHyeY3TSTuo
Cleanflight failsafe setup https://www.youtube.com/watch?v=dikr9oDzQqc

Set failsafe on receivers with failsafe built in

See also Lemon Rx set #Failsafe
See also on OrangeRX R616XN Review [2] https://www.youtube.com/watch?v=UUzjYCzqsxQ

Video Transmitter

Important! - Always make sure your VTx antenna is attached before powering up your Eachine Racer 250. Running it without the antenna can result in VTx failure.

The OSD built into the VTx displays the current pack voltage, elapsed time, and transmitting channel. There is a power LED between the red button switch and the metal screening box on the VTx (see photo below[3]). If this LED is not illuminated and the VTx is very hot to touch it is likely that it has failed

A short press of the red button on the top of the VTx will move the OSD down slightly each time. A long press will change the channel.

Use the table below to find the corresponding frequency to the displayed channel. Make sure to set your VRx to the exact one. Example: channel "a4" displayed in the OSD would correspond to 5805 GHz.

VTx Frequencies

[4]

1 2 3 4 5 6 7 8
A 5865 5845 5825 5805 5785 5764 5745 5725
B 5733 5752 5771 5790 5809 5828 5847 5866
C 5705 5685 5665 5645 5885 5905 5925 5945
D 5740 5760 5780 5800 5820 5840 5860 5880

Parts & Accessories

Suggested list of parts and accessories

Replacement Parts

KingKong 5040 Propellers BANGGOOD or kingKong 5040 Replacement Propellers HOBBYKING
Gemfan 5040 Glass Fibre Nylon Propellers BANGGOOD
DTI 5030 Propellers (same as original) [1]
HMF Q250 Frame Arms BANGGOOD or HMF Q250 Frame Arms ALIEXPRESS
Eachine Racer 250 Drone Spare Part BG2204 2300KV Brushless Motor CW/CCW BANGGOOD
Eachine Racer 250 Drone Spare Part Simonk 12A ESC 2-3S BANGGOOD
Eachine Racer 250 Drone Spare Part M2.5*8 M3*8 M2.5*5 Screw Set BANGGOOD
470uf 25v Capacitor 105c High Temp, Radial Leads AMAZON and ESC Direct solder Picture 1Picture 2
470uF 25v SMD Capacitor 105c High Temp, 10pk (more factory-like replacement) AMAZON

Accessories

AOMWAY 5.8Ghz RP-SMA-Male Antenna for the Video Transmitter and Video Receiver BANGGOOD [5]
Aomway 5.8GHz FPV 4 Leaf Clover AV Transmission RHCP Antenna 1 Pair for the Video Transmitter and Video Receiver BANGGOOD
B6AC Charger BANGGOOD or Turnigy Reaktor Charger HOBBYKING
Prop Balancer BANGGOOD
Lipo Safety Charge Bag BANGGOOD
Eachine 5.8Ghz Video Receiver BANGGOOD or FR632 With Diversity Video Receiver SURVEILZONE
OrangeRx R616XN DSM2/DSMX Compatible 6CH CPPM Nano Receiver with Failsafe HOBBYKING
Quanum DIY FPV Goggle V2 w/5 inch LCD Monitor (Kit) HOBBYKING
Eachine EV800 5 Inches 800x480 FPV Goggles 5.8G 40CH Raceband Auto-Searching Build In Battery BANGGOOD
FPV Goggles or Display
Action Camera
Batteries to power up VRx

Receiver

PWM Receiver Connections

[6] The wires coming from the FC to Rx are:

RBW channel 1 and power
Blue channel 2
1st yellow channel 3
Turquoise are light blue-green channel 4
2nd yellow channel 5
Black channel 6
Ch 5. Flight Mode
Ch6. Accessory

PWM wiring for Spektrum RX:

Data = Blank
Thro = Black/red/White cable(pins 1,2&3 on CC3D connector)
Aile = Blue Cable (pin 4 on CC3d)
Evel = Yellow (pin 5 on CC3D)
Rudd = Green (pin 6 on CC3D)
Gear = Yellow (pin 7 on CC3D)
Aux1 = Black (pin 8 on CC3D)

Connecting remote lights to Spektrum receiver

[7] How do you get the lights working on your transmitter while using pwm on a 6ch receiver???

1. Assuming you have all 6 wires plugged in from the board connector to the receiver - unplug black wire #6 from your receiver (far right wire on board plug).

2. Take it out of the board plug by prying up on the small plastic tab and pull the wire out of the connector.

3. Plug the yellow line (5th from the left on the control board plug) into your aux channel on your receiver.

4. Take the small black and white plug that came with your quad and connect it to your board next to the on/off switch and plug it into your gear channel on your receiver.

5. Turn off the lights!!! Very important here, the switch must be off for the radio to control the lights.

6. With all the wires now connected and the black #6 wire removed from the control board plug...connect your quad to computer.

7. Turn on your transmitter and then plug in your lipo battery into the quad.

8. Click on transmitter set up wizard. Calibrate both sticks and the gyro switch for flight modes. Important - skip the other switches!

9. Don't forget to reset your arming settings as the wizard automatically turns arming permanently off for safety reasons.

10. Test your gear switch. It should cycle the lights now.

PPM Receiver Connections

The Eachine Racer 250 flight controller has the ability to accept a PPM signal from a receiver. 3 wires are used. When using a PPM receiver and Cleanflight/Betaflight use the servo plug with three wires pins 1,2,3 (black,red, white) that comes from the FC straight to your RX pins.

Modify Flight Controller Cable for PPM (not for use with Cleanflight/Betaflight)

Use a pin or exacto knife to lift the plastic tabs on the white connector and black connectors, and then remove the wires.

SBUS with the X4RSB Receiver on OpenPilot

[8] The X4RSB comes in two configurations, and the only difference is the firmware loaded into it.

The original X4RSB configuration supported SBUS on the 4th connection which gave channels 1 - 16 on SBUS, along with channels 1,2, and 3 on the first 3 PWM channels.

Later a CPPM firmware was introduced an many vendors now sell the receiver with this firmware loaded. With the CPPM firmware if channels 2 and 3 are connected together when binding, the configuration will be channels 1 - 8 on CPPM (PPM) on channel 1 pins. Channels 1 - 16 on the SBUS pins on channel 4, and channel 9 on the channel 2 PWM pins and channel 10 on the channel 3 PWM pins. NOTE: If channels 2 and 3 are not jumpered when binding, the receiver will work the same as the original firmware.

Connection to the CC3D flight controller:
With the V3+ board, the cable in the photo gallery below was included.

This cable connects into the MAIN port of the CC3D board. The black, red, and yellow wires connect to the SBUS port of the X4RSB receiver with the black being ground, red being 5V, and yellow being the signal wire connection to RX on the FC. Tuck blue wire out of the way, or remove it from the connector.

Open Pilot:

Now that the X4RSB receiver is wired to the FC, the next step is to tell Open Pilot to enable SBUS. See the photo of the Hardware config page from Open Pilot and view the main connector to SBUS. Lastly, go to the RC inputs page and tell Open Pilot the inputs are from SBUS. See the photo, this is from user wild.bill's set up. Individual users' configuration of the actual channels may be different, but they are still SBUS. In addition, there is flight mode setup info, and ARMing using a switch images in the gallery below.

SBUS on Futaba R7008sb with LibrePilot

Receiver supports sbus and sbus2. Successful setup using sbus.

Check the mode the receiver is working in - red flashes on the receiver when powered on. Out of the box it was set to mode 4 which didn't work. - Set to Mode 2 (of 4) which provided channel 1-8,

Modify one of the supplied cables (black,red,green/purple,yellow). - Remove the green cable. - Plug cable into 'main port' on CC3D. - On the R7008sb, insert into channel 8, black bottom, red middle, yellow top.


Transmitter

Deviated Devo 7e and 10 PPM Setup Guide

Do NOT connect the propellers to the quadcopter throughout this process.

  1. Modify Flight Controller cable for PPM cable
  2. Download Dropax media:Model8.ini.txt (remove .txt file extension) for the Devo Eachine Racer 250 and model icon media:Racer250.bmp[9]
  3. Copy the the model.ini to the Devo transmitter by connecting the transmitter to the computer via mini USB cable
  4. Disconnect the USB cable
  5. With the transmitter, load the Eachine Racer 250 model.ini by selecting to Model Menu, Model setup, Load, Eachine Racer 250
    caption
  6. Within "Model Setup" scroll down to "PPM in" and select "Channel"
  7. Download and open Openpilot
  8. Connect a mini USB from your computer to the CC3D flight controller (a warning will display saying "Firmware Version Mismatch" which is okay)
  9. In Openpilot GCS, run Vehicle Setup Wizard and upgrade firmware
  10. Follow the on screen instructions
    1. At the Binding step during Vehicle Setup Wizard
    2. Prepare the receiver to bind. See #LemonRx Example
    3. With the transmitter, select Model Menu, Model setup
    4. Scroll down to select the protocol i.e. DSMX/DSM2
    5. Select Bind
    6. Confirm with your receiver that the lights on the receiver flash accordingly
  11. In Openpilot GCS, select the bottom Configuration tab
  12. Select Input
  13. Select from the top Arming Settings tab
  14. Decide on choosing an "Arm airframe using throttle off and:"
  15. Disconnect
  16. Confirm transmitter is able to send signal to the receiver by attaching battery
  17. Select appropriate flying area, connect propellers, battery, and go fly
Lemon Rx PPM Receiver Binding
Eachine Racer LemonRx PPM.jpeg

Binding Setup[10]

  1. Plug bind plug to the receiver.
  2. Provide power to the unit.
  3. Enable bind mode in transmitter and ensure distance separation of 2 meters from receiver.
  4. Upon successful binding and if FailSafe do not wish to be set, remove bind plug upon binding.

Setting Failsafe

Step 1: Start by binding the receiver to the transmitter in the normal way.
Step 2: Proceed as follows to set failsafe (see video: https://www.youtube.com/watch?v=FyW1v12dv_k)
  1. Ensure that transmitter and receiver are turned on.
  2. Insert bind plug into the receiver (Note: to set failsafe, bind plug is applied only when the receiver is turned on).
  3. Set transmitter controls to the desired failsafe positions.
  4. Press the side pushbutton to memorize failsafe settings.
  5. Observe that the green light at the end of the receiver turns on to indicate failsafe is set. (Repeat step 4 will cause the LED to turn off which means failsafe is disabled).
  6. Remove bind plug.
  7. Disconnect the power for at least 2 seconds and then reconnect the power again.
  8. Test failsafe by turning off the transmitter without propellers connected.
OrangeRx R616XN PPM Receiver Binding
See also on OrangeRX R616XN Review https://www.youtube.com/watch?v=UUzjYCzqsxQ
FlySky i6 (Eachine i6) Set Tx Failsafe

Hold bottom trip buttons inward while turning on the transmitter. Then, long press the OK button to get into the menu. From here, navigate to MENU>RX SETUP>FAILSAFE. Set Channels 3, 5 and 6 to -%100 (if you keep getting 98-99% for values, hold the throttle stick down while pressing OK). After settings have been changes, long press on the CANCEL button to save. See Video for more assistance.

OpenPilot

OP is the default FC software which comes pre-loaded on the EC250.

PIDS

PIDS are highly dependent on flight setup, which includes props, battery size, externally mounted camera, etc. and also when new firmware versions are released. With each component change, the values in gyro filters and/or other features will be needed to tune again. The user postings of PIDS is to provide an approximate value covering a specific flight setup, so that pilots can tune further from there.

Users can try these Open Pilot PID's for an initial starting point, which will need tuning to dial in. These are designed for use with a 1500 mAH Lipo mounted on the lower plate. Note: these are not tuned for use with Gopro or other camera.:

These PIDS were derived from the Brandon Hill video found here:
https://www.youtube.com/watch?v=u2-dq2_SxvA

Roll: Kp 0.0034 Ki 0.0119 Kd 0.000046

Pitch: Kp 0.00454 Ki 0.01589 Kd 0.000061

Yaw: Kp 0.00794 Ki 0.01509 Kd 0.000067

BetaFlight

Firmware Installation

Flashing through Openpilot

BetaFlight is a GCS based on the CleanFlight platform but is being developed by Boris B as a separate thread of software.

Eachine Racer 250 FPV ARF - Flashing to BetaFlight firmware by FyreSG

YouTube https://www.youtube.com/watch?v=6m0Fj5ct9vU

There are 6 main steps:[11]

  1. Download and install Chrome and CleanFlight Configurator.
  2. Download the firmware binary image.
  3. Run OP and do not connect your CC3D board to your computer.
  4. Select the firmware file and click the firmware update button, then connect the USB cable. It should flash the firmware to your board.
  5. Reconnect your board and run CleanFlight Configurator. If you don't have it, install Chrome and then the configurator.
  6. You need to set motor mix and check the RX channel assignments. Also choose the PIDC and PIDs that you like.

For your convenience the CLI commands for re-assigning the motor order is below, these can be cut/pasted into the CLI: The offset 0.930 has been calculated specifically for the Eachine racer 250.

Copy and paste the following:

mixer custom
mmix reset
mmix 0 1.0, 1.0, -0.930, -1.0
mmix 1 1.0, -1.0, -0.930, 1.0
mmix 2 1.0, -1.0, 0.930, -1.0
mmix 3 1.0, 1.0, 0.930, 1.0
save

To confirm that the changes were saved:

mmix

Also Note the following when moving from OP to CF.

If you have your CC3D setup for PPM on OpenPilot, continue using PIN 8 for signal. As of 5/24/16 Betaflight uses PIN 8 for signal. Previously, the signal from the receiver was moved from PIN 8 was to PIN 3.
CleanFlight GCS might not connect to the CC3D as easily as OP, you need to ensure the correct driver is loaded first.
When connecting the USB cable to the CC3D FC, CleanFlight needs power to be applied to the CC3d BEFORE the USB interface will work. There are two ways to achieve this
  1. Connect the battery to the FC first, then connect USB... after connection to GCS is made you can remove the battery,(remove props for safety).
  2. The second option is to place CF into "autoconnect" then slowly plug in the USB cable half way, until you see power LED's flashing on the FC but the PC has not "chimed" to show USB detected, this applied power only. Then wait for the FC to boot. After FC boot insert the USB cable fully to connect the USB signal control lines (the PC will chime to show connection)... this can be tricky but it works.

Flash through USB to serial adapter

Required:

USB to TTL Serial module Banggood
Sign up for an account and download the STM flash programmer http://www.st.com/content/st_com/en/products/development-tools/software-development-tools/stm32-software-development-tools/stm32-programmers/flasher-stm32.html

Video instruction https://www.youtube.com/watch?v=svkwzbgo0OI

PIDS

PIDS are highly dependent on flight setup, which includes props, battery size, externally mounted camera, etc. and also when new firmware versions are released. With each component change, the values in gyro filters and/or other features will be needed to tune again. The user postings of PIDS is to provide an approximate value covering a specific flight setup, so that pilots can tune further from there.

Users may try the following PIDS[12] (as of BetaFlight 2.1.6) for an initial starting point, which will need tuning to dial in.

       P    I      D
Roll   1.2  0.026  15
Pitch  1.2  0.026  15
Yaw    4.2  0.040  10

Receiver Channels

When installing BetaFlight/CleanFlight, and using a PWM receiver, the channels need to be reassigned. This can be done as a hardware mod (rewiring pins on the cable from the receiver to the flight controller board) or by changing some settings on the Eachine i6 transmitter.

Receiver wiring[13]

BetaFlight PWM Wiring.jpg

Remapping channels using mixes on the transmitter[14]

Get into the i6 menu by holding the horizontal subtrims inwards whilst turning the power on, then holding down ok. Go into 'functions setup' -> 'mix' (on the second page).

Setup Mix #1 like this:

Mix is On

Master Ch1

Slave Ch5

Pos. mix 100%

Neg. mix 100%

Offset +0%


Hold down cancel to save that configuration.

Next go into the menu Functions->Aux. channels. Change Channel 5='Source None' and Channel 6='Source SwC'. Hold down cancel again.

Try channel map of ETRA1234 in CleanFlight Configurator on the Receiver page. Check that all of the channels work as expected on the Receiver page. If they don't, change the order of the letters or numbers (eg ETAR1234) until they do.

Motor Mapping

[15]

Motor Mapping
Physical Position CleanFlight Eachine 250 KK2.1
Bottom Right 1 CW 2 CW 3 CW
Top Right 2 CCW 3 CCW 2 CCW
Bottom Left 3 CCW 1 CCW 4 CCW
Top Left 4 CW 4 CW 1 CW

Multicolor LEDs

The multi colored LEDs in the more recent versions, which are also sold separately on BANGGOOD, are standard WS2811S LEDs (also called NeoPixels) with an integrated stepdown converter for the power supply. They can be controlled using the NeoPixel library for Arduino, configured at 400khz. Even if these LEDs are 5V, the LED bar needs to be powered with more than 5V, due to the built-in stepdown converter (UBEC) allowing it to run directly on a lipo. Power it with at least 6-7V. Betaflight and cleanflight have integrated neopixel support, allowing to control the lights right from the flight controller.

Ws2811s led bar.jpg

Extras

3D Print an Eachine Racer 250 Mobius Mount by equaldo

Cleanflight Blackbox Beta - This is an interactive log viewer for flight logs recorded by Cleanflight's Blackbox feature. It allows logs to be browsed and exported as WebM video.

Aluminum Case HARBORFREIGHT

Eachine Racer 250 Handbag Backpack For Eachine Racer 250 Drone I6 Radio Transmitter Parts BANGGOOD

Setting up a X4RSB Receiver: [http://www.rcgroups.com/forums/showpost.php?p=33489355&postcount=4555}

Mods

There are two special versions of this tray designed to work with a revised FPV camera servo tilt (video) and a 36mm D4R-II receiver mount.

  • Mod to stock FPV cam plate for increased rear tilt
Eachine Racer 250 stock camera tilt mod.jpeg







Troubleshooting

Replacing Capacitors

[16]

BetaFlight Mini USB Port Connection Issues

In cases where the computer cannot see the CC3D flight controller over a mini USB connection. [17]

  1. Install the VCP_V1.4.0_Setup.exe (it will in fact extract some files into C:\Program Files (x86)\STMicroelectronics, check if it is the same folder)
  2. Plug the CC3D to your computer. With BF you always have to boot the board with external power before connecting USB and one has to reconnect USB if reboot was triggered by configurator.
  3. In your device manager, right click on the unknown device and update the driver
  4. Search for the good folder on your computer and install the driver
  5. Disconnect your CC3D from the USB. Plug your lipo, wait 10/15sec, plug the USB. You should normally see a virtual com port now.

Eachine Racer 250 Groups

http://www.rcgroups.com/forums/showthread.php?t=2461697
https://www.facebook.com/groups/eachineracer250fpv/


References

  1. From user TheMadCADer on the RCGroups forum: http://www.rcgroups.com/forums/showthread.php?t=2461697
  2. From Painless360 on YouTube: https://www.youtube.com/channel/UCp1vASX-fg959vRc1xowqpw
  3. Original photo provided by Alec Wood
  4. From Youtube video by Brandon Hill - https://www.youtube.com/watch?v=BLL29sQvrYg
  5. From user WreckingBall on the Rcgroups forum http://www.rcgroups.com/forums/showthread.php?t=2461697&page=141&highlight=5040#post33131504
  6. From user DarkAngel74 on the RCGroups forum: http://www.rcgroups.com/forums/showthread.php?t=2461697
  7. From user Buudy22 on the RCGroups forum: http://www.rcgroups.com/forums/showpost.php?p=33862826&postcount=7229
  8. From RC Groups forum wild.bill and users http://www.rcgroups.com/forums/showpost.php?p=33412196&postcount=4011
  9. http://www.rcgroups.com/forums/showpost.php?p=33286002 Dropax Devo model.ini and model icon uploaded with permission
  10. http://www.lemon-rx.com/shop/index.php?route=product/product&path=70&product_id=138
  11. From user FyreSG on the RCGroups forum: http://www.rcgroups.com/forums/showthread.php?t=2461697
  12. From RC Groups post by FyreSG: http://www.rcgroups.com/forums/showpost.php?p=33534028&postcount=4916
  13. From user lazyeyes on the RCGroups forum http://www.rcgroups.com/forums/showpost.php?p=32986840&postcount=1565
  14. From user gofergo on the RC Groups forum http://www.rcgroups.com/forums/showpost.php?p=33719297&postcount=6163
  15. http://wiki.siftah.com/Eachine_Racer_250_CleanFlight_Motor_Mapping
  16. Photos courtesy of Ethan B
  17. From user Atranoob on the RCGroups forum: http://www.rcgroups.com/forums/showthread.php?t=2461697&highlight=version+flexi&page=207