[PSUBS-MAILIST] deep water tests - release mechanism

[AndrePevestorf@aol.com]

In einer eMail vom 12.04.2002 10:51:29 (MEZ) - Mitteleurop. Sommerze schreibt thijs-struijs@planet.nl:
> I agree on that. Are there any psubbers who actualy tested there sub in deep
> water? How was it done?

Hi,

The only diving test I had ever carry out was with "DIOGENES I" (a wet dragged minisub). 
It was designed as a unpowered dragged search sled with a hydrodynamic shape for higher speed. So we tested it of course while dragged. 

The advantage of this procedure is that you can change very quick your altitude with a single shift of the diving plans (wings). The sub itself has positive bouyancy, the diver in it has a jacket for extra bouyancy....

For small shallow water subs it could be a procedure to test manned subs. The surface supply boat is always there and you donŽt have to build in the sub engines. But what you need are diving planes. 

For "DIOGENES I" the final wings and the steering mechanism was not installed (I recall was not yet designed ..) so we attached a simple board with negative pitch angle under the hull. The idea was that there will be a balance between the surface boat speed, the downward force from the diving planes the drag of the sub and its positiv bouyancy.

The diver inside was able to influence the bouyancy by means of regulation his wetsuit and the surface boat was able to vary the dragging speed (has a good speedometer and a good old diesel engine ...)

Did it works well ? NO !!!

The subs centre of gravity wasnŽt deep enough due to his flat design. WeŽd better attached the Wings ON TOP of the hull !!! 
But so the poor man inside the "can" (wasnŽt me... was fortunately a high skilled navy diver how could handle the situations as well..) flighted on spiral after the other ... harbour bottom at 15 feet ...next station near the surface ... return to the bottom .... 
I guess he feeled like in a roller coaster indeed...and we on the surface dragged him with 2-3 kn straight ahead ...

I highly suggest some comunication gadget !!! 
(we planed to use a simple watertight push button in the sub and a alarm lamp on the supply boat but nothing was finished and the date with the supply boat could not be shifted ones more..)

Some pictures about "DIOGENES I" will coming soon in the picture gallery.....

For a static unmanned sink test dive I believe the most important gadget is the release mechanism. I`m not sure but I guess there are something about this topic in the PSUB archives....

The second important point is to keep a watch on any changes inside the boat. A water sensor might be usefull in the bilge and a pressure gauge or a pressure switch is a good choise too.

And last but not least one of the cheaper CCD cams with wide optics can give you a picture of the actual situation.

Another important question is the LAKE or the SEA !!! How far away is the next deep seafloor ??? And how to reach this spot? Is it really usefull to test the unmanned sub with full instalations??? (engines, switchboards, batterys...)



A.