At the beginning, I bought the Lego Technic 42020 (pictures below). It’s a small medical helicopter, with blue and white color. But I was disappointed by look and functions: rear hold can be opened but you can put nothing in the helicopter, front wheels are moving freely. Globally, the structure of the helicopter is strange and complex.
So, I decided to build my own twin-rotors helicopter, with 4 landing wheels like the Boeing CH-47 Chinook 🙂
On this small helicopter, there are synchronized rotors which can be moved via the rear axle, front wheels steers for taxiways (from a small lever on the roof), and rear hold can be opened. Some lights are present, one on the front, two on the side, and two at the back. Initially, I would like to add various bricks or other parts on the side of the helicopter, but the style wasn’t good at all. So I decided to let it “open”, with 2 yellow plates on the side: one on the bottom, which is contiguous to light and curved slope, one on the top to give more width around the motors.
Rear landing gears are more spaced than front ones, to ensure better stability when the helicopter lands. Also, it wasn’t possible to have a bigger spacing for front landing gears due to steering. I would like to add a hook under the cabin but unfortunately, it was not possible, or helicopter frame has to be different with more parts but never mind.
In conclusion, this small helicopter is fun, easy to build, very small turning radius… And approved by my nephews 🙂