![Plane Hammer Step 11](https://www.origami.org/wp-content/uploads/2023/10/12-plane-hammer_0011.jpg)
Step 11: Fold the inner triangle over to the right side
![Plane Hammer Step 12](https://www.origami.org/wp-content/uploads/2023/10/12-plane-hammer_0012.jpg)
Step 12: Fold the top of the plane down to meet the bottom and press down the crease
![Plane Hammer Step 13](https://www.origami.org/wp-content/uploads/2023/10/12-plane-hammer_0013.jpg)
Step 13: Fold the outer top corners inwards and diagonally down to meet the centre ‘cross’ of the previously made crease marks (indicated in red)
![Plane Hammer Step 14](https://www.origami.org/wp-content/uploads/2023/10/12-plane-hammer_0014.jpg)
Step 14: Your plane should now look like this
![Plane Hammer Step 15](https://www.origami.org/wp-content/uploads/2023/10/12-plane-hammer_0015.jpg)
Step 15: Open up the paper
![Plane Hammer Step 16](https://www.origami.org/wp-content/uploads/2023/10/12-plane-hammer_0016.jpg)
Step 16: Fold the inner section upwards, creating the crease line indicated in red
![Plane Hammer Step 17](https://www.origami.org/wp-content/uploads/2023/10/12-plane-hammer_0017.jpg)
Step 17: Your plane should now look like this
![Plane Hammer Step 18](https://www.origami.org/wp-content/uploads/2023/10/12-plane-hammer_0018.jpg)
Step 18: Fold the outer ‘wings’ in half, folding them in to meet the diagonal crease lines
![Plane Hammer Step 19](https://www.origami.org/wp-content/uploads/2023/10/12-plane-hammer_0019.jpg)
Step 19: Fold the outer ‘wings’ over towards the centre once more
![Plane Hammer Step 20](https://www.origami.org/wp-content/uploads/2023/10/12-plane-hammer_0020.jpg)
Step 20: Fold the top of the plane downwards, creating the crease line shown in red