[PSUBS-MAILIST] New Dutchman

After my first mail to the list a week ago I recieved som questions from Michael Holt and Carsten Standfuss. Well, 20 years ago I started building a 1atm. GRP submersible. As I wrote you this project was cancelled.

At this moment I am in the design fase of another GRP 1 atm. sub with a maximum divingdepth of 100 mtr.. I followed your discussions on GRP as a constructionmaterial and I agree that steel is a far more secure material. I missed one argument. As we are HOMEBUILDERS we have to cope with our own abillities. For me a steel submersible would mean letting it build by someone else but with wood (molds) and GRP I can do a lot. I have al lot of friends working as yachtbuilders. They will be there to advise and help me.

Although it is possible to make almost any shape in GRP I chose a sphere as a pressurehull. This is by far the strongest and safest shape. Arond the viewports and hatch there wil be steel reinforcement rings. It has an ID of 1150 mm. Hullthickness is 50 mm. There are 2 small main ballast tanks (MBT's) in front and aft off the pressurehull. There is no conningtower but a free flooding sail on top of the sphere. This sail can be opened and closed with a valve. Once surfaced the valve is closed and the sail will contribute to the bouillancy of the sub. On top of the sail there will be a small tv camera on a pan and tilt mechanism. The VBT will be placed inside the pressurehull. I think it will be a "soft" tank, vented to the interior of the sub. It wil be emptied with a pump. I think the advantage of this construction is that it is panic-proof (easy to operate). Another advantage is that these tanks can have almost any shape as long as you keep the center of gravity in mind. For example one can use the armrests as VBT.