6S FT Edge “Dancer” build log

[perhapsleiana]

I remember being on here back in the days when Grifflyer was active. Fun kid, I actually got to fly with him a few times. My flying style has definitely changed since then, and my most valuable experiences flying have been ones with unexpected failures- foremost a battery that slid back in a fuselage, making the plane unstable, but… very easy to hover.
Now that I’m in school as a fine arts major, I’ve moved to using this hobby primarily as an art form- feats of technological skill will happen with or without me but as an art medium, model aviation is mostly still in its “baroque period”- the idea of using it to express emotion is still rare.

Thats where this plane comes in. It’ll serve as a blank canvas for aerobatic dance, which so far I’ve only seen in the form of precise aerobatic routines set to music, mostly with indoor flight. It’s typically more of a show of precise skill than an artistic expression. This plane is meant to fly dramatically, and to take advantage of my specific skillset as a pilot.

I’m starting with a speed build kit, mainly because I only have so much time being a student and all. Im going 6S and aiming for an AUW of about 2.4-2.5 pounds, because much of the flying I plan to do will be hanging on the prop anyway. For now I’m using a power system centered around a 50A ESC, but I may upgrade later to 100A, since the motor should be able to handle a 10 second burst of that.

The key unique feature of this plane will be variable and hopefully independent wing sweep to effectively alter the CG in flight. It requires less force than moving the battery, because the wings simply weigh less and don’t experience much longitudinal load other than acceleration.

So far, I’ve gotten the main airframe and power system done but I still have landing gear and wing servos to do.


And the internal pivoting system (note the position of the pivot):

And with one wing removed, showing the spar system (so far):


I hope this build pans out. I still have to simulate it, but I won’t have time until Tuesday for that.

 

[FoamyDM]

Looks like an interesting and repeatable idea.. I can't wait to see it in action

 

[sk1234]

These are amazing

 

[perhapsleiana]

Looks like an interesting and repeatable idea.. I can't wait to see it in action

well, get your song requests in!
Edit: Slower songs work better with this build, given its size.

 

[perhapsleiana]

Did most of the sim work today. Still gotta test independent wing sweep and fully enter in the rail dimensions. (Sorry it’s not a real screenshot, I’m tired and I just wanted to log where my CG is set in the sim)

 

[perhapsleiana]

Finished the simulation step! I'll definitely have to keep an eye on knife edge performance and downsize the more vertical nose strakes- I do want this plane to track straight in yaw. I may raise the battery up to the top of the fuse or somehow put the sweep servos in the top of the canopy or add a dedicated receiver battery there in order to raise the CG up.
At some point I hope to start using X-Plane for this step, but the UI on the editor for X-Plane is even worse.

 

[perhapsleiana]

Using colored carton sealing tape (thinner tape with acrylic adhesive rather than rubber- stands up better to the elements). I’ll paint some later today hopefully.

The sweep mechanism was tough to get working smoothly, but it helped a lot to lubricate the sliding surfaces. Adding a thin plywood vertical strip spar also helped. Lastly, adding small rollers to the canopy hatch made it finally move smoothly.

 

[telnar1236]

"feats of technological skill will happen with or without me"
"The key unique feature of this plane will be variable and hopefully independent wing sweep to effectively alter the CG in flight"
Sounds like a pretty innovative technical idea to me
The plane looks great, and the idea of flying to music is a cool one. Can't wait to see how it flies

 

[perhapsleiana]

"feats of technological skill will happen with or without me"
"The key unique feature of this plane will be variable and hopefully independent wing sweep to effectively alter the CG in flight"
Sounds like a pretty innovative technical idea to me
The plane looks great, and the idea of flying to music is a cool one. Can't wait to see how it flies

Have a little faith in the hobby, cmon

 

[perhapsleiana]

Finally did the maiden flight last night! I was about to take off when I realized that a plane made for expressing emotion needs a name.
Her name is Taryn and she flew very well. Took a bit to trim out, and I think I'm going to use more expo.
The wing sweep worked really well. Sweeping wings forward both effectively moves the CG and reduces tip-stall tendency at the same time.
Honestly though, she may have been a touch underpowered, but that's fixable- I limited the throttle to 70% and I can just increase that limit.
As for handling... it really felt like dancing, and everything felt so... smooth? It could be because I used larger servos, but there's still something about the handling that's unique and amazing.

Got a little too excited and failed to recover from a spin before hitting the ground, but it wasn't too bad of a crash. I managed to land belly-first and only broke the landing gear and some other minor frame damage, but I already have all that repaired. I'll put in a higher C rating battery and make power limit adjustments another time.

She's... She has so much potential and I'm really excited.

 

[perhapsleiana]

It’s been a bit too windy to fly lately, so I’ve taken the time to do some detailing and power system adjustments.
An airplane for dancing has to have more humanity to it, and while you might think imperfections in the initial build would add to that, they really don’t. The philosophy of it is more or less “children are perfect, but adults have been injured and worn down.” Tracing the etymology of “adult” will actually lead you tho this same concept. Emotionally expressive performance art is typically more focused on negative emotions, and I knew a perfect airplane would struggle to express that, so I had to make it look more injured.

I swapped out the receiver for a flysky ia6B, and I’ll be adding some telemetry- battery voltage and motor temperature first. Having motor temperature alarms will help me be able to overdrive the power system without burning anything up- this power system will draw 1000W or so, and sustaining that will cause it to overheat, but in this case that doesn’t mean I can’t give it full throttle for a few seconds.

Lubricating the sliding parts of the wing joints has been a challenge, but I’ve found that the anti-chafe moisturizer I use works really, really well for this.

 

[perhapsleiana]

Got Taryn up in the air with the new paint today- she looks magnificent in the sunset. I fitted her with voltage and motor temperature telemetry, and audible alarms for overheat… which came in handy when the motor half-seized in flight. It looks like a few of the magnets slid back and were grinding on the base of the motor, enough to get the temperature of the base up to 100 Celsius. I got a new, better motor ordered, but I think I’ll still try and fix this one.

Also worth noting I had an aileron linkage pop off (Clevis wasn’t secured enough I guess) during one of her flights today, and the asymmetrical wing sweep actually came in handy. Sweeping the wing with the free-floating aileron forward really helped smooth out handling after the mechanical failure.

Most of the flying today was practicing point rolls though. Just getting used to how she handles. On one landing I did manage to pull off a true spot landing- wings swept forward, near-vertical approach, nose high attitude of 60 degrees up or so.

She’s… she’s really made to dance. The engineering I put to to her is engineering and very much technical, but at the end of the day, she’s a work of art more than anything else.

 

[perhapsleiana]

After another 8-10 flights or so, here's a (cut and edited) video of an attempt at actually dancing- the video I got wasn't great, and most of it was out of focus, because the guy who recorded it didn't do a good job.

 

[perhapsleiana]

The build is mostly done at this point, but there's one big problem in the design, and honestly it's a flaw in the design philosophy of the FT Edge itself. As a 4S (400-500W) build, the airframe is on the heavy side, which is why I went 6S 1000W in the first place. Problem is, the strength of the airframe is more uniform throughout than it should be, and in my build I've had to reinforce the motor mount, and I've gone through multiple iterations of landing gear designs. Next up is heavier aluminum landing gear with some kind of trailing link struts.

 

[perhapsleiana]

Gave up on trailing link struts. Built the landing gear, and it does work, but the additional failure points don’t seem worth it- also alignment would be a huge pain.
My actual problem was using landing gear that was more suited for a plane weighing about half as much.