VX1: 154.5 mph World Speed Record Quad

By Phanny P on May 10, 2017

2 649  13 

This is the first of the VX series of frame projects. More info: https://downanddirtydrones.com/portfolio/
A lot of engineering, physics, calculations, trials, concepts, crashes, time, etc. went into developing this frame: https://downanddirtydrones.com/drone-physics/

Contrary to how this build looks, it is not at all awkward to fly. In fact, this is now my favorite frame to fly (now that I put the camera angle at 40°)!

EDIT: I have changed the speeds below. I selected "Imperial" in the Betaflight OSD options. After using this setting for the first time, logic led me to believe that the OSD wasn't showing mph (since it would have been WAY too high). The next possibility was ft/s since it was supposed to be imperial. However, I am 95% sure (and the blackbox log pretty much verifies this) that the OSD is still showing km/h... NOT happy since this has made me look like a fool, but I want to keep it honest...

Just broke the speed record and hit an average of 244.5 kmh (152 mph) with a 5s! However, score board goes by max ground speed which was 154.5 mph


Note 1: OSD speed is in kmh. A list of the speeds recorded, direction, and time in the video:

212 kmh (131.7mph) West to East 0:31
230 kmh (142.9mph) East to West 0:47
240 kmh (149.1mph) West to East 1:06
248 kmh (154.1mph) East to West 1:21
241 kmh (149.8mph) West to East 1:34
HOWEVER - GOING FOR AS MUCH AS I CAN GET: Blackbox/gps log says 69.06 m/s which is 154.5 MPH
Blackbox Log File: https://drive.google.com/file/d/0Bw5AmHq7h72NQU1tamt5VkljUzA/view?usp=sharing
GPS Log File: https://drive.google.com/file/d/0Bw5AmHq7h72NaEdxRnRTa21lOEU/view?usp=sharing

To rule out any wind (which was calm), I took the highest reading from each direction and averaged them to get 152 mph.

Note 2: Flight took place around 8pm on May 26, 2017 and winds were 5mph max: https://www.wunderground.com/history/airport/KPTK/2017/5/26/DailyHistory.html?req_city=New+Hudson&req_state=MI&req_statename=Michigan&reqdb.zip=48165&reqdb.magic=1&reqdb.wmo=99999

Note 3: Very poor OSD reception/quality. The Eachine DVR records a black screen if there is any interference.

Note 4: After much research, I have found out that GPS is the most accurate way to determine speed. A summary of my findings: https://downanddirtydrones.com/gps-vs-radar-gun/

Note 5: Flight ended in a small crash - I thought I had turned on angle mode, removed my googles, pulled back on the stick to land it and realized too late I was still in acro.


Part List


Down and Dirty Drones (2 builds)
See Site

Flight Controller

BetaflightF3 Flight Controller (3 builds)


4 x Super RacerBee 30A BLHELI_S (Now Dshot Ready!) (2 builds)


4 x Cobra Motor Black CP2207 2450kv (2 builds)


RK5051 Triprop Smoke (Set of 4) (3 builds)

FPV Camera

Crazepony 700TVL Wide Angle FPV Camera 700TVL 3.6mm Lens NTSC for QAV250 (3 builds)

FPV Transmitter

AKK X1 40CH 25mW/200mW/600mW Switchable FPV Transmitter with Push Button and Digital Display (7 builds)


Anbee FPV 5.8Ghz Circular Polarized Clover Leaf Antenna High Gain Aerial Set w/RP-SMA Plug (4 builds)


Lemon Rx DSMX Compatible Diversity Satellite (DSM2 backward compatible but must use DSMX compatible primary receiver) LM0037 (10 builds)


SMC Extreme 1400mah 4S Racing Battery - True Spec Extreme (11 builds)

Misc Parts

Tarot Dia 10MM 3K Carbon Fiber Tube Boom 280MM TL68B22 For FY680 Quadcopter Hexacopter Multi Rotor (3 builds)

Misc Parts

MIDWEST PRODUCTS 5742... CARBON FIBER STRIP,.057x.177 ( (2 builds)

Misc Parts


Misc Parts

Micro uBlox M8N GPS GLONASS W/ (18x18mm) (3 builds)

Misc Parts

MagiDeal Pack of 4 Carbon Fiber Tube 8*6mm 330mm DIY Vanished Surface Tail Tube (3 builds)

Misc Parts

Braided Carbon Fiber Round Tubing ~ 1.75" ID x 24" (2 builds)
See Site
Show stores (9)


Sign in to comment.
showintellpro   15 days ago  

Yeah.. This is an interesting design.
I'm curious.. You said this was not designed for speed, but it ended up that way, what was the original intent?
Based on the motor set up, I'd imagine it could max out speed without increasing camera tilt and each motor should be at best efficiency (not compensating for craft angle/weight distribution).

Phanny P   15 days ago 

I have a bad way of wording things sometimes... It was meant to be fast, but I had the camera (accidentally) set more for a speed run type quad. It is hardly flyable the way the camera was which made it exclusive to flying it as a speed run quad only (I was probably hitting 80-90mph to maintain altitude by the time I pitched low enough to see the ground). I did fix the angle and might fly it tomorrow. And, yes you are right - camera angle won't have any effect on speed.
Main intent is to see the flight characteristics compared to the VXS (https://rotorbuilds.com/build/4104) design which has the arms angled and gives a more efficient cross section at tamer speeds.
Lots of ideas - never enough time to get them across as clear as I like. I appreciate the questions so I can get a chance to clear up my ideas/intent!

metropolis   19 days ago  

Niiiiiiice job man! :D

Phanny P   19 days ago 

Thanks! Too bad the same couldn't be said about the video - gotta change out the prodvr. Any static and it records a black/blue screen. Also going to add a diversity rx to my ev800 this weekend :)

Are you sure you want to unfollow this person?
Are you sure you want to delete this?
Click "Unsubscribe" to stop receiving notices pertaining to this post.
Click "Subscribe" to resume notices pertaining to this post.