Usually models for shipbuilding are downscaled. They are display and presentation models and have a special relevance in wind channel and towing tank experiments. On one hand they have to be accurate in size. On the other hand diverse shapes are often needed for wind channel and towing tank experiments. Therefore the requirements regarding a good price/performance ratio are high.
Original sized models are especially used for mock-ups to test the technically feasibility or to present detailed solutions towards the owner representatives.