DISCLAIMER

The purpose of this guide is to educate those interested in manned submersibles and the elements required to build one for experimental and / or personal use. It is for educational purposes only! This guide does not constitute advice, it is not definitive and it can be modified and / or deleted at any time without notice. While manned submersibles have an excellent safety record to that of other modes of transportation, their operation and maintenance requires specialized knowledge. Like any experimental vehicle, the operation of a manned submersible can expose the operator to unexpected situations which may cause bodily harm and / or death!  It is the sole responsibility of each individual to understand the principles of operation of a manned submersible and to discern when it is safe to operate or not to operate the vehicle through a combination of education and experience.

BACKGROUND

Throughout history, man has had a fascination with the underwater world. Four Hundred years before the birth of Christ, Aristotele wrote about a specialized diving aparatus used by  divers to collect sponges at depths of up to 100 ft.  They were basically inverted boxes wighed downd with heavy stones which kept an air buble close to the diver. The diver would leave the bubble to collect sponges and instead of going to the surface, he would return to the air bubble to breathe from the  fresh air in the reservoir at the working depth and therefore make his collection efforts more expedient.

In the 1600's King James I contracted a Dutchman to build a submersible craft which was operated by 12 rowers. This vessel was said to have a special device which would purify the air allowing the vessel to remain underwater for several hours at a depth of approximately 15 feet in the Thames River. These are just two of many examples of the earliest attempts by man to explore the undersea world.

Today, the underwater technology has advanced to the point that virtually anyone with time, money and motivation can build his own submersible craft. However, relatively few people have really had the desire to do so. For years Manned Submersibles have been pretty much the domain of the military, governments, research institutions and a few private individuals. Why is it that the airplane acquired such a huge popularity with the general population and the submarine did not? The answer lies in the technical difficulties of designing and building manned submersibles.

Manned submersibles require more technical expertise than an aircraft to design and build. Since  you are entering a world in which human life can not be sustained by natural means, the  technologies used to sustain life in the cabin of a  manned submersible are identical to that used to keep astronauts alive in space. In order to sustain life in a sealed envorionment, a clear understanding of the  gases involved and how to control them is required. The user must understand how to precisely control the Oxygen levels required to sustain life and how to remove the poisonous levels of  Carbon Dioxide generated by the human metabolism,  and to keep the pressure inside the cabin as close to atmospheric pressure as practical.

Another hurdle for the proliferation of submersibles in the private sector is that the vessel's hull and systems outside the hull are exposed to very large static pressures as it ventures deeper into the sea. This pressure increases at a rate of approximately 14.7 PSI for every 33 fsw or 0.4455 PSI per fsw (foot of sea water).  This means that the metals selected for the hull must be strong, ductile, and designed for the maximum depth intended for the vessel (with a safety factor of at least 2:1 built-in).  This in turn will make the submersible extremely heavy compared to a typical experimental aircraft.

With today's advancements in technology, it possible for virtually anyone design and build his own experimental submersible. For the most part, experimental submersibles are small, basic in design, relatively inexpensive and safe to operate. In this series of guides I will attempt to explain in as simple terms as possible, the technologies required to design and build your own manned submersible.