Mujin Wakusei Survive - 1x35 - Although We Don't Have Enough Materials- Followmy.tv

With Shingo designing and Porte giving technical advice while recuperating from his injuries, the children start to build their ship with Pague's help, using the largely intact hull of the Orion for the main body, and searching the forest and ruins for parts and components. However, a disagreement caused by lack of parts is starting to open a rift between Shingo and Porte. Since the gravity control unit they found wouldn't be powerful enough to produce both lift and propulsion for their ship, Shingo comes up with the idea of using sail power for propulsion, but Porte rejects it outright, not willing to ignore centuries of tradition in spaceship construction.