Vimana89
Legendary member
Some of you are already familiar with this design. I built basically the first version of it (before having a name) for the Build-Ruary challenge with a three step(KFM 3 I believe?) air foil on an F pack radial motor, and while it showed nice handling, was underpowered and horrendously inefficient on battery duration. I built the second version(which became the standard successful one) a couple months back as part of the quarantine build-off, using a 2 step KFM1 style air foil and "old" B pack motor, and it's been my go-to all-around 4ch flyer ever since.
I recently built a micro sub-250g version on a radial A pack, and while I'm still tweaking props and CG a bit, it flies really nice for its size and gives a full 4ch flying experience in a small package, while showing that the design scales well. I figured I'd give the design its own thread and share my design and build process, as well as my experiences flying both the original and micro versions so far.
So what is the Hawk Moth all about? Well, It's a really simple 4ch tractor-prop design with a highly swept wing similar to that of an English Electric Lightning using a KFM1 style air foil (in my case I used a simplified version with no fold/just glued). The fuselage is just a basic B fold "noob tube", and although there is a full fuselage, rudder, and small horizontal tail surface above the VS/rudder, it's effectively a tailless (or at least semi-tailless) design in that the tail section does not extend past the wing tips, and elevons (rather than ailerons) on the wings are utilized.
The inspiration came from a plane on Outerzone called the "Blitz", which itself is basically a shortened, semi-tailless version of a Lightning with a tractor prop. I simplified this design further for easy foam board construction, and changed up the rudder section a bit, but the concept is basically the same.
Building is a no-brainer, and flying is easy, although I would definitely not say first plane/trainer level easy. The handling qualities are somewhat like I'd expect a swept-wing cold war jet to behave, crossed with a hint of flying wing (although the high sweep gives it a bit more "pendulum stability" than your average wing, and the position of the rudder makes it a lot more effective). It yanks and banks well just with the elevons, but also really responds great to rudder, which gives it a ton of maneuverability.
Both axial and barrel rolls are super clean and crisp, and the plane banks extremely smooth(and can hold a really steep bank almost like a knife edge very gracefully). Wingover turns are great, and it can loop decent too, but with loops on mid size or larger versions some altitude and technique are required because it loops wide and carries a lot of downward momentum. This plane has no nasty stall characteristics, and any stalls will be gentle.
This is definitely no dedicated slow flyer, but generally handles well at lower speeds, especially with the right setup. Higher speed handling is good too, and it could be very fast if set up for speed. The design is flexible and well-rounded for a lot of situations and a great all around flyer. The micro version is a little more touchy/squirrely, has a faster roll rate, and loops a bit better.
I recently built a micro sub-250g version on a radial A pack, and while I'm still tweaking props and CG a bit, it flies really nice for its size and gives a full 4ch flying experience in a small package, while showing that the design scales well. I figured I'd give the design its own thread and share my design and build process, as well as my experiences flying both the original and micro versions so far.
So what is the Hawk Moth all about? Well, It's a really simple 4ch tractor-prop design with a highly swept wing similar to that of an English Electric Lightning using a KFM1 style air foil (in my case I used a simplified version with no fold/just glued). The fuselage is just a basic B fold "noob tube", and although there is a full fuselage, rudder, and small horizontal tail surface above the VS/rudder, it's effectively a tailless (or at least semi-tailless) design in that the tail section does not extend past the wing tips, and elevons (rather than ailerons) on the wings are utilized.
The inspiration came from a plane on Outerzone called the "Blitz", which itself is basically a shortened, semi-tailless version of a Lightning with a tractor prop. I simplified this design further for easy foam board construction, and changed up the rudder section a bit, but the concept is basically the same.
Building is a no-brainer, and flying is easy, although I would definitely not say first plane/trainer level easy. The handling qualities are somewhat like I'd expect a swept-wing cold war jet to behave, crossed with a hint of flying wing (although the high sweep gives it a bit more "pendulum stability" than your average wing, and the position of the rudder makes it a lot more effective). It yanks and banks well just with the elevons, but also really responds great to rudder, which gives it a ton of maneuverability.
Both axial and barrel rolls are super clean and crisp, and the plane banks extremely smooth(and can hold a really steep bank almost like a knife edge very gracefully). Wingover turns are great, and it can loop decent too, but with loops on mid size or larger versions some altitude and technique are required because it loops wide and carries a lot of downward momentum. This plane has no nasty stall characteristics, and any stalls will be gentle.
This is definitely no dedicated slow flyer, but generally handles well at lower speeds, especially with the right setup. Higher speed handling is good too, and it could be very fast if set up for speed. The design is flexible and well-rounded for a lot of situations and a great all around flyer. The micro version is a little more touchy/squirrely, has a faster roll rate, and loops a bit better.
Last edited: