Re: [PSUBS-MAILIST] Hookah Sub (First Try)

[DJACKSON99@aol.com]

In a message dated 10/7/02 7:50:05 PM US Mountain Standard Time, jeffpost@rawbw.com writes:


> 1) plexiglass not tempered glass for the view ports


I was thinking that plexiglass would tend to bend outward from the positive preasure in the top of the cabin.  Does it do well when its flat?   I'll see if I can find something about its bending strength.

> 2) I don't have enough info here, but if you want to descend to 33', how long 
> will it take your compresor to raise the volume of the cabin by 1 atm? Can it 
> give you the volume you need, fast enough? I'm sure other ambients use 
> bottled air which would compensate the cabin much faster. I'm curious to see 
> the results of your calculations.
>
> 3)How long will your supply lines be? If you want to be able to descend to 
> 60', you might need lines a couple hundred feet long. How does having supply 
> lines that long affect the volume of air supplied? 
>
> Here's the clincher: I have a feeling that if you simply tow the hooka, a 
> slight  tug on the lines might pull your hooka under! When you use the hooka 
> for diving, you obviously can't pull hard enough with you mouth to do this, 
> but your proposed sub has hundreds? of pounds of thrust, and is vastly more 
> massive than your hooka float.. I think this is the real spoiler with this 
> particular design.
>
> As an alternative, could you redesign your sub to put more of the structure on 
> the surface? How about a small barge that tows you behind it? Maybe the 
> underwater portion could have minor attitude adjusters, but to really move 
> from place to place, the barge would provide the main thrust.
>
> JP