Micro Motor Community

Burt's (Helio) Spring Adventures at Kittyhawk -- Build Journal


It’s been a long time since I posted here, but that’s because it’s been a long time since I built out something end-to-end. Besides getting a little more time flying vs building, I did get distracted by @NotFastEnuf’s Boss frames for a few, though I haven’t been able to keep up with his rocket-fast firmware work (damn!)…

Anyhoo, for documentation purposes, here’s a build journal of Tristan Semmel’s Akos frame project. In case you didn’t hear of Tristan, he designed this last year at the age of 16, and took the frame through a cool design/mfgr process. Check it: http://www.kittyhawkfpv.com/#/kittyhawk-1/

This is mostly inspired by his spirit of adventure, so I call it the Kittyhawk, cuz Wright Brothers, and I’m stickin’ to that story.

This is built from various parts (instead of any component kits), and is powered by a Helio Spring, which will absolutely be using Butterflight and I’m looking forward to checking that all out. Besides playing with this frame, I tried Racewires for the first time (the larger 40mm x 8mm ones), and this is also going to be me trying out Lumenier motors for the first time; traded them for two Tattu R-Line batts that were gifted to me.

After a lot of back-and-forth, I decided to put the Racewires in front of (reversed) prop strikes to the frame – easier to replace a sliver of PCB than the frame; I’ll be mounting them to the frame with (old!) VHB that I hope will hold. I haven’t decided on my cam solution yet, leaning towards a RunCam Swift Micro with TX200 VTX, but I believe the Helio has some decent OSD/cam support that is new to me. I also wired up the S.Port lead from the XSR, but I’ve never used that before either, we’ll see if I really do use it.

After a decent build session tonight, I figured I’d share where I’m at so far.

  • Akos Frame
  • Helio Spring FC
  • Cicada 4in1 30A ESC
  • Lumenier 2204 2300KV motors
  • FrSky XSR Rx
  • Racewires (large)

We’re at about 208g so far.

Latest Pic:

Frame Kit Contents

Early steps

Wiring up the innards


A little more work completed… all that remains to is the camera, props, binding, and BuF config.

Finished wiring the motors to ESC via Racewire

Dry fit the top plate

Added arm stiffeners


Ooooh ive missed the Burt exclusive journals. Glad to see another one. That frame is so worthy of building up. Cant wait to hear of your review!

Uve inspired me to log my 5" LOS build; Burt style! With lots of detail, but not too many and easy on the eyes.


Great build and documentation! Was the racewire really necessary? The arms are vertical, so there was little chance that the props could cut them.


Racewire necessary? Eh, I got the motors used, and the wires were as you see in the photos, a bit short. I could have extended them, but figured I’d try the Racewires.

Thanks for the compliments, @MidnightQuads, @SkyNectar!


Ah, that makes sense.


All done now. Notes…

When flashing the Helio Spring FC, do NOT use what’s available in the Butterflight configurator… it’s incomplete. Use the firmware from https://www.heliorc.com/wiring/. What I experienced was my ESCs booting with only the first four rising tones, but they wouldn’t complete the sequence regardless of ESC protocol, reflashing, whatever… Using the correct firmware from that page did it, and configuration was simple, nothing more than Receiver and Modes, really.

Cheating with the camera, I did use the Runcam Swift Micro and matching TX200. Mounted using it’s own metal bracket. I am concerned about the dinky antenna placement… we’ll see how that behaves.

Lastly, inspired by the Immortal T antenna, I poked holes in a “forever tube”, and strung my XSR antenna up-and-down. It’s inconvenient for sitting on the ground, but I intend to fly this.

p.s. I did need to remap motors with the RESOURCE commands in CLI. Only one motor needed direction changed, though, lucky me!

All I need now are prop nuts… but here’s the “finished” product:


Nice build!

What’s the AUW?




A couple flight vids, nothing thrilling, just more documentation… although the crash was handled easily by the frame, no issues at all.

Helio Spring + Butterflight + Kittyhawk ftw!


How do airbrake arms feel like in turns? I imagine them feeling quite grippy


I didn’t feel that “airbrake” effect at all… but I don’t turn very hard as a practice, more cruising. It seemed nice an slippery cruising, though!


I think it’s an interesting concept especially for racing. From most reviews of frames that have similar arms, reviewers have always commented on how well they turn. It hasn’t taken off yet (excuse the pun) so maybe people don’t the benefits are worth it