3S Cobra GT M3

By HK-AERIAL VTOL on Jun 18, 2019

9  170  0

This is not a nice build. It’s been patched up a couple times from my “learning phase”. The reason I am sharing this quad is that it's a good flier and noobs should see the things that we learned on. This configuration flies like it is literally on rails and (despite my preference) it has been rebuilt following an aerial test of the distance limits of the XM+ (I got “RX LOSS”. It sucked!). The rebuild saw the purchase of my second HGLRC stack, the F428. I reused 3 of the Cobra 1407 4100KV’s and the XM+. I have 2 GT-2018 5” monsters and so I figured this might be a good frame (in all honesty… meh). All that being said… the thing blasts. It can’t take that great of a hit, but I guess any reliable signal and power feed to Cobra’s is going to result in a mindblowing flight. This quad does just that. From impossibly low and fast inverted-S turns to full-speed all pitch turns (hold down…. You know… while your cocked 90 degrees). Of course, Venom provides the necessary power as they deliver the best experience IMO. HQ V1s for 3"... no need to explain.
A build like this is great for a noob. Not only is the final product very flyable on stock PIDs (uhhh… not 4.0, use 3.5.7 FTW), but it retains the handling of a 2” with the speed of a full powered 50A+ 5” monster. It's power to weight ratio is as high as it gets and that is more forgiving to me (I would rather have the power to turn to avoid something if I had to). I fly this guy every day no matter what. I do not think it can die. The VTX + huge cap sled is an altered thingi courtesy of this guy “Dookie” at work. He did it the right way with the zip tie hole going between the two cavitities. If you want it message me. It works killer with the shape of the frame, and yes… in my last crash… I tore off the SMA. No big deal. I had to replace most of it anyway.

p.s. While I was typing this up I ran across this: https://rotorbuilds.com/build/13959 . I'm pretty sure I just followed that cat's lead (I built my Diatone's about that long ago). I've used RB a lot for finding quad parts, but I don't feel I should post without propping out the folks that inspired me to build.


Part List


Diatone 2018 GT-M3 143mm Stretch X FPV Racing Frame Kit RC Drone 3mm Arm (5 builds)

Flight Controller

HGLRC 20x20mm Micro F4 Flight Controller AIO Betaflight OSD 5V BEC for XJB F425 F428 Series Flytower RC Drone (16 builds)


HGLRC 20x20mm 28A BLheli_S BB2 2-4S 4 In 1 ESC Support Dshot600 for XJB F428 F328 Series Flytower (8 builds)


4 PCS Cobra CP 1407 4100KV 2-4S Champion Series Brushless Motor Golden for RC Drone FPV Racing (2 builds)


HQ Prop 3x4x3 V1S Tri-Blade 3" Prop 4 Pack - Choose Your Color (32 builds)

FPV Camera

FXT T81 Venus 800TVL NTSC/PAL 16:9 4:3 switchable cmos camera with voltage reading 4.3g

FPV Transmitter

Eachine TX526 5.8G 40CH 25MW/200MW/600MW Switchable AV Wireless FPV Transmitter RP-SMA Female (123 builds)


Realacc RHCP Super mini UXII Stubby 5.8GHz 1.6dBi FPV Antenna For TX RX Fatshark Goggles RC Drone (42 builds)


FrSky XM+ SBUS 2.4GHz Mini ReceiverDefault Title (1368 builds)


Venom 75C 3S 850mAh 11.1V Drone Racing LiPo with Universal 2.0 Plug (3 builds)


FrSky Taranis Q X7 2.4GHz 16CH Transmitter (White) (205 builds)


Fat Shark Dominator V3 FPV Goggles (56 builds)

HD Camera

GoPro Session (60 builds)

Soldering Iron

YIHUA 908+ 220V 60W Electric Iron Soldering Station Welding Rework with Soldering Stand + Cleaning Ball + 5 Tips
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