Dual Prop Sport (original)

Free plans and 3D print files below!
FPV version

Fun little plane - quickly launches into the air, nimble, super fast and precise rolls, and the dual props makes taxiing a breeze when using differential thrust.   The 40" wings make it easy to throw in the back of the car or could easily be carried on a backpack.  The extra motor makes it a bit more complicated to build (more soldering, etc) but the added benefits makes it totally worthwhile.  If you've build other foam planes (TestFlight.com, RCPowers.com, etc), go for it.

Great for FPV!!

Bonus - detachable landing skiis and wheeled spring suspension landing gear add to the fun.

  • Small size: 40" wingspan, 30" length makes it easy to transport
  • 3d printed motor mounts: 
    • ESC cavity allows for great air flow with minimal wind resistance.
    • Propeller held in place with rubber bands, protecting motor mount to wing bond during any mishap.
    • Cooling vents to keep motors cool in summer (and just looks cool).
  • Dual motors allow steering while taxing (why walk over to your plane when you can have the plane come to you), as well as providing yaw control in-flight
  • Sporty, with fast and precise rolls
Battery: 1300-3000mAh, 3s
Motors: X2206 1500kv Sunnysky (18g)
ESC:  10-20A, 21mm max width, (12A velotech, 1A BEC)
Prop: Turnigy Slowfly Propeller 7x3.8 Black (CW & CCW), or similar
Servos: 3, 9g (elevator can use 6g servo)
Receiver -  6+ch (2 motors, 2 ailerons, 1 elevator, minimum)

Weight: 440g (~120g fuselage + 320g wing)
  +30g (FPV gear)
  +90g (suspension landing gear) or 70g (skiis)
  +190g (2200mAh)

3D models  (Thingiverse link)

  • Fuselage, two options - same design:
                      a) Sides individually cut out (RCPowers style)
                      b) Sides cut out with connecting 'flaps' (FlightTest style)

Assembly: A bit more complicated with the additional motor, just use battery Y-harness and use 2 receiver slots into the receiver for the two motors.  Much of the assembly is similar to that with the Twin Boom Pusher, as the wing chord is the same.  Likewise, I also recommend mounting the receiver in the wing for easier connection with the fuselage as shown in the Twin Boom Pusher video build instructions.  A rudder is optional, but I found it is not necessary with differential thrust.


Wheeled spring-suspension landing gear - entire setup under 90g
  - using 3" lightweight wheels
  - better tracking over rough grass fields and not-so-soft landings
  - larger wheels would work even better


Parts List
 - Foamboard (2 pcs dollar tree foam or similar, 20x30")
 - 5mm x 1M carbon fiber tube (recommended to stiffen wing)
 - 3mm x 1M carbon fiber tube (used in wing attachment mount, wheel suspension, etc)
 - typical foam place building supplies as needed (hot glue, epoxy, packing tape, hinge tape, etc)

Wheeled Spring Suspension:
 - Brass tubing (5/32, 1/8"), cut to length as needed
 - Springs, 2" L, .025" OD, .023" wire diameter (up to .025" should work, found in local hardware store)
 - fishing line (10#, or similar)

Build Effort:  Medium

- Added photos and stl file for wheeled spring-suspension landing gear

 - Version 2 completed, wing and fuselage drawings updated.
 - With the snow melting, rubber-band suspension wheeled landed gear tried out, needs work!

Fall 2019
 - Added spring suspension landing gear - works great!


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