227kmh!!! 5kg AUW Hybrid Stretch Wishbone

I made a new type of frame! It’s a hybrid stretch, with forward mass bias. Some of the concepts behind the design have been done in miniquads; I used to race with the battery slung forward from way back, as do a few very fast guys I know like Michael Douglas. There are two main reasons, firstly if you have experience looking at many blackbox logs of full forward flight it becomes apparent that the rear props are always working harder than the front. So by moving the mass forward, it balances out the loading between front and rear. I’ve found it’s quite a taboo topic with everyone having a very strong opinion and dismissing anything outside of their beliefs on it, however anyone who has objectively tried it and compared both their blackbox logs and their laptimes, using an A-B methodology, knows that creating this loading balance makes the quads just fly better; it tracks straighter in forward flight, makes dive gates easier, banks at a more efficient attitude and is just night and day in terms of lap times and control consistency.

Aside from testing this frame design at this big heavy size, one of the main points with this test was to determine the accuracy of the Brain GPS unit when used to measure top speed. Many people believe Betaflight GPS functionality in terms of speed in particular to be inaccurate. The only way to properly test this is using this methodology, as speed guns reportedly have accuracy issues as well; they can pick up the movement of an individual propeller blade!

The results from the fixed cam were amazing. The two fastest passes over the 10m length (in opposite directions) were exactly 23 frames in length (filmed at 120fps), both the exact same. This calculates out to be 187.8km/h, reviewing the DVR, at the same point on each run (the middle of the 10m length), the OSD was reading 185kmh. So if anything the Brain GPS is understating the top speed.

The highest speed recorded on the OSD was 227kmh on a south/west pass. The north/east pass peak was 207kmh, so that’s a top speed average of 217kmh for both directions.

Setup:

Concept frame
Turnigy NanoTech+ 6000mah 12S2P
APD F3[x] 120A
APD PDB500
Autek Alpha13 Prototype 14P
MAS 13x12x3
Radix FC
Brain GPS
Luminier VTX
XSR
Betaflight 3.5.7

[momp]

The sound and speed of that thing! WOW. That's scary 😁 Nicely done!

[TheTonstar]

Awesome mate I got a super stretch 5 flys good 👌

[josephsteventon]

Hey, cool videos. Love the size of these quads! I currelty fly a 7 inch but have been involved with larger projects up to 23's but havent ever foot the bill for them. I would like to build one but im wondering what the cost diferences are like? would you mind giving some info on prices? Thanks in advance =D

[shogunemperor]

New video!!!! That super stretch looks weird! Hahaha VERY interesting design! How does she fly?

[modocfpv]

nice! Those are BH T10? Which KV? Did you replace the wires?