Firefox Mig-31 Twin 70mm EDF

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This build is for a Firefox Mig-31. The fictional plane that Clint Eastwood stole from the Russians in the 80’s move Firefox, and flew by thinking in Russian through the brain interface hemet! I have always been a big fan of the movie and this was my chance to fly this futuristic fighter! (without having to learn Russian)

Please read the entire guide before deciding to build, so you know what’s involved and how it goes together.

I would love to see another one besides mine at FF 2023!

Here is some info on the Mig-31 designation:

https://theaviationist.com/2017/12/01/the-story-of-the-mig-31-firefox-all-you-need-to-know-about-the-most-awesome-fictional-advanced-high-speed-interceptor-ever/amp/

Specifications:

Wingspan: 1210mm (~48”)

Length: 1445mm (~57”)

Powerplant: twin 70mm EDF

CG: 57mm (2.25”) back from angle in wing edge.

Weight of model, no electronics: 25 ounces.

Electronics:

4 channel receiver minimum

3 servos. qty2-17G for ailerons, qty1-9g for canard elevator.

Battery 6S 4000mah

EDF: qty2-70mm

Supplies:

Hot glue gun and glue

5 minute epoxy

10 sheets of 20x30 Dollar Tree Foam Board or FT Foam board.

1/8” (3mm) ply and a way to cut shapes out of it.

qty1 20x30 poster board (black) for thrust tubes.

Plans:

PDFs - https://drive.google.com/drive/folders/1PM1uxAzRssRJw4OudWtIGWnlUv7641mU

Assembly Manual  - https://drive.google.com/file/d/1c71Voeo8P3PgYu3WB_VP6lBrF-9M-9yP/view?usp=drivesdk

Assembly pics - https://drive.google.com/drive/folders/1g_hii2xQpyiefxPV9fDozstFtdEqgA8i?usp=sharing

Radio Setup

Setup radio making the ailerons on the wing act as elevons, like a flying wing. 

WARNING: For the front stabilizer, I mixed it into elevator channel so that very minimal movement happens, I seriously limited the throw. It moves up or down maybe 5-6mm each deflection. it takes very little movement in the front stabilizer to affect pitch. It should be setup as an assistant to the elevons, which provide plenty of pitch control.

Flying characteristics: 

Tracks straight and true, the delta wing makes it a slight rolly at slower speeds, and I added 40% expo to the elevons. But bring it in straight and it lands smooth and slow. Don’t try to bank hard at slow speeds, or you may stall.

video Maiden:

https://youtube.com/shorts/e9oTM0xGdM4?feature=share