Goblin Mash - Ups: 5 Different Versions and Plans Including A-10 and Foam Wonder Mash-Ups

**Goblin Mash-Ups Build Plans - Click Here**

Build Plans for:
A-1065 / Goblin Mash-Up
A-1075 / Goblin Mash-Up
Foam Wonder / Goblin Mash-Up
Goblin with a Tail AKA Kobold
Goblin 140% (Will be updated shortly)


Recommended Parts:

Electronics Overview Video - How I wire twin-engine planes.
Note: Thanks to all of the designers of the original plans / 3d designs. These plans are my rough attempt at modifying some plans and sharing them. All of these builds will require some improvising and modifications but should be easy for any scratch builder. I just want to share my take on these builds and share some of the fun I had with the community. I will update this thread with any additions/changes to the plans. If you build any of these, please post in the FT forums or Facebook Flite Test Fans page! Please let me know if you have any suggestions or find any issues with the plans and I'll fix them if I can.

A-1065- @ 65% and the Goblin @ 100%
Wing Span: 40 inches
CG: on the leading edge of the spar
Flight Video


This version flew awesome. The linked video is a flight I got in on a windy day over a lake (one of the flights ended with the A10 taking a dip in the lake lol). This version used two 1507 quad motors spinning 4-inch props and 30 amp escs. You could also use the 2207 motors I listed in the recommended parts above. It flew on a 1300mah 4s, 1800 mah 4s, and 2200 3s. The build is pretty straightforward if you have scratch-built a plane before.

Build Tips:
  • Spars -When building the wing I did not use the entire spar section from the plans. The spars didn’t scale down very well. To spar the wing I used 2 of the sections starred in the photo below. This same technique was used for all sections of the wings. If I built it again I would add a carbon arrow or dowel rod in the main wing to add some additional support, but it flew fine without it. I used 3d printed motor mounts, but a good substitute would be the power pod and nacelles from the FT Superbee. The motors were mounted about 4 inches away from the fuselage, or right at the end of the main wing.
  • On plans for the 65% version, I did not use the cutouts in the fuselage for the wing. I built the fuselage without the wing cutouts, then hand-cut the bottom of the fuselage to fit the wing.
  • To add some strength to the horizontal stabilizer I used a popsicle stick to connect the two sides.
  • The “Jet Engines are toilet paper rolls with foam board wrapped around them…
  • The cockpit is from the FT Mustang. I had to cut it down to get it to fit.
  • Spar Pic - I only used the starred section. I cut two of these out for each section of the wing. The wings held up fine in flight, but I’d recommend adding a carbon spar or wooden dowel in the main wing.

A10-75 @ 75% and the Goblin @ 115%.
Wing Span - 46 Inches
CG- Leading edge of the main spar
Flight Video


This build is the exact same as the 65% version just a little bit larger. Here are a couple of pics of how I mounted the motors, PDB, and servos. This wasn’t pretty, but I was just making things up as I went. I added all of the electronics after the plane was built. If built again might route the motor and servo wires inside the wing. I also didn’t like the motor mount I used on this version. I’d definitely use these Motor Mounts when building again.


Foam Wonder / Goblin Mash-Up
Goblin Scaled to 115%
GC - Marked on Plans - Stock goblin location
Flight Video


FT Goblin (scaled up to 115%) and Sponz's new Foam Wonder as a Twin-Engine plane. This thing flies amazing (and by amazing, I mean nearly identical to the actual Foam Wonder, which flies awesome as well)! This and the Foam Wonder are some of the most locked-in Flite Test planes I have flown (and I have built most of them). Both are great for park flying, fpv, or just some line-of-sight cruising. This version cruises around just like the Goblin but has substantially more control and maneuverability than the goblin without the tail section. The version shown in these pictures is my first prototype, so some things may be updated in the build plans.

Build tips:
  • The fuselage builds just like the normal goblin but this is just longer. I built the entire fuselage, then slide it over the completed wing and glued it on. This is scaled up to 115% so the A and B folds are a little bit larger than they are supposed to be, but I didn’t notice this affecting the build at all.
  • To build the wings you need to bevel cut the leading edge of the upper and lower sections, then join them together with tape along the whole leading edge. The spars have a cut-out for the servo if you want to mount the servo like it is done on the stock goblin. I chose to mount the servos on the underside of the wing as shown in the pics. You will need servo wire extenders if you go this route.
  • The lower wing section may be a little long in the plans. Cut the lower wing section so the elevator moves.
  • To increase the strength of the vertical stabilizers, I doubled them up and bevel-cut the leading edge



The motors were mounted to the Motor Mounts and glued roughly 4-5 inches away from the fuselage. I wanted to make sure to get clearance for 6-inch props.
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