Algorithm notation. The Helicopter Cube turns around its edges, so its notation names edges rather than faces. An edge move is named by the two faces that meet at that edge: UF UR UB UL FR FL BR BL DF DR DB DL. Each move flips that edge 180 degrees, so no 2 or prime is needed, and the letter order does not matter (FU equals UF). Brackets repeat or invert a group: (UF UR)x3 or (UF UR)3 and (UF UR)'. Jumbling moves, where a layer stops half way, are not modelled. The second input loads an algorithm into the player under the puzzle, played on the puzzle as it stands (set up a scramble with the first input): step through it with the buttons, press play, or click a move to jump there.

Helicopter Cube simulator: solved on the left, scrambled on the right

Online Helicopter Cube Simulator

Free Helicopter Cube simulator in 3D: flip the twelve edges, scramble, time your solves and step through algorithms right in your browser. No download needed.

Helicopter Cube Simulator: Practise the Edge-Turning Cube

The Helicopter Cube is a twisty puzzle that looks like an ordinary cube, but it never turns a face. Every move is a 180-degree flip around one of the twelve edges, which swaps two corners and two pairs of the small triangular centres. Adam G. Cowan came up with the idea in 2005 and built the first one in 2006 with 3D printing. The puzzle shows 8 corners and 24 centres, four on each face; the edge pieces it turns around stay hidden inside.

Solved Helicopter Cube with four triangular centres on each face
The diagonal cuts split every face into four triangular centres with a corner piece at each tip.

This Helicopter Cube simulator lets you try the puzzle before you buy one, learn a method without the fear of losing a solve, or warm up between sessions with your real cube.

How to use the simulator

  • Turning: drag a sticker toward an edge and the wedge on that edge flips. Drag the empty background to orbit the cube and check the faces you cannot see.
  • Keyboard: the QWER, ASDF and ZXCV rows flip one edge per key, from Q for UF to V for DL.
  • Scramble, Undo and Reset: Scramble mixes the cube with an animated random sequence, Undo takes back your last move and Reset returns to the solved cube.
  • Timer: Scramble sets the timer to zero but does not start it, so you can inspect the cube first. Press Start or the Space bar to begin, and again to stop.
  • Algorithms: type a sequence in edge notation and press Apply, or load it into the player under the cube and step through it move by move. The demo algorithms under the notation notes are a quick way to see what short sequences do.
  • Sharing: the link and embed boxes turn your scramble and algorithm into a URL or an iframe for your own page.

A solving approach

Most people solve the Helicopter Cube face by face, roughly as the Ruwix Helicopter Cube solution guide explains:

  1. Build the four centres of one face, much like the cross on a 3x3x3.
  2. Add the four corners around that face.
  3. Fill in the remaining centres by pairing them up and flipping each pair into place, one side at a time.
  4. Permute and then orient the last corners with short algorithms.

The part that surprises newcomers is how the centres move. With 180-degree flips the 24 centres fall into four separate groups of six, and a centre can only ever visit the six spots of its own group, one on each face. If a centre will not go where you want it, that spot belongs to another group: look for the matching colour from the right group instead of forcing it. Because each flip is its own inverse, a sequence is undone simply by playing its moves in reverse order, which makes it easy to experiment in the simulator and back out of anything.

Is the Helicopter Cube harder than a Rubik's Cube?

It is different rather than simply harder. There are fewer piece types, but the moves feel unfamiliar and the centres wander between faces in a way 3x3x3 Rubik's Cube solvers do not expect. Most people find the first solve slow and later solves much quicker once the centre groups make sense.

Does the simulator do jumbling moves?

No. A physical Helicopter Cube can be turned part way so that it changes shape, which is called jumbling. The simulator plays the standard 180-degree flips only, which is all you need to scramble and solve it.

Physical Helicopter Cube jumbled out of its cube shape
A jumbled Helicopter Cube: partial turns let pieces swap into odd positions and the puzzle loses its cube shape.

How is it different from the Curvy Copter?

The Curvy Copter, designed by Tom van der Zanden, uses curved cuts, so its twelve edge pieces become visible and have to be oriented too. You can try it in the Curvy Copter simulator.