OTW Designs produces model submarines for the serious modeller. We do our very best to be as accurate and detailed as possible. Our models are museum quality, and designed fully in-house. The designs have been thoroughly tested for in excess of six years, and found to satisfy the requirements of the most exacting model makers.

Many independent opinions hold that these are probably the best submarine models available anywhere today.

The Type 7 model, in particular, has received accolades from America and Germany, amongst others, and has been described as “probably the best crafted (model submarine) kit available anywhere in the world”.

Every single model on this site has been constructed from start to finish by Bob Dimmack and his partner Steve Warner, who have conducted all the research, design, and development.

Although the models will make superb static display items, they are primarily intended for use on, in, and under the water. All models can take the OTW Designs dive system. This system – sized to suit the model in question – works by true submarine action. To submerge, water is pumped into ballast tanks, compressing the air trapped inside them. The density of the submarine is thus increased, and this allows submergence. To surface, water is pumped out of the ballast tanks, allowing the trapped air to expand. This reduces the density of the submarine and causes it to surface.

Despite popular belief to the contrary, only relatively small changes in density are required – or desired! If the density is slightly less than that of water, the sub will surface (float); if it is slightly greater than water, it will submerge (sink).

Other OTW Design modules are recommended to maximize the performance of your model. The trim system (auto leveler) controls the rear dive planes to keep it level underwater – unless of course the operator wants to dive or to surface the model. And the emergency blow system can surface your model in the unlikely event of a problem.

With the electronic drive package, battery status is continually monitored, so that in normal use your model will surface with enough power left to return to you before the battery becomes exhausted.