Re: [PSUBS-MAILIST] Impact Calculations..

["Captain Nemo" <vulcania@hawaii.rr.com>]

Alec,

I think you're idea is a good one.  I've gone that way too.  Now, we have
bubble windows on the NAUTILUS, covering thicker flat ports than we used
before.  The intent was mostly ornamental:  to match scale exterior
appearances; but it will have the second advantage of protecting the actual
windows, too.

And Carsten, what you said is so true!  Every time I took the NAUTILUS to
the Marina, the test-videos show somebody tapping on the glass.  One old guy
even tried to scratch the starboard viewport with his ring!

The funniest one was when we had it on display on its trailer in the parking
lot of a dive shop that was sponsoring a show of new SCUBA equipment.  I was
talking to a guy, when he interrupted and pointed behind me.  I turned
around and there was a young girl, maybe eight years old, hanging by her
arms and swinging from the ramming spur like it was a piece of gymnastic
equipment or something!

Just then, her Dad came and led her away.  I hope she enjoyed herself.  I
didn't mind.  There certainly was no danger of her hurting the sub.

Next, the dive shop owners brought out some girls wearing bikinis to pose
for photographs on the submarine.  I wasn't worried about them breaking or
scratching anything, but someone did express the opinion that they were "so
hot they might melt the plexiglass".    ;-)

On a more serious note about  Impact:  one thing we see on a lot of subs to
protect against impact damage are various forms of what might be called
"crash bars".  These make good sense.  In keeping with the Disney design, my
NAUTILUS MINISUB's inner pressure hull  is completely surrounded on all four
sides with heavy steel guards, and the ramming spur on the bow is solid
steel, securely welded.  They have proven their functional worth in zero
visibility water.

Pat







----- Original Message -----
From: "Carsten Standfuss" <MerlinSub@t-online.de>
To: <personal_submersibles@psubs.org>
Sent: Tuesday, July 02, 2002 6:56 AM
Subject: Re: [PSUBS-MAILIST] Impact Calculations..


> Alec Smyth schrieb:
> >
> > I haven't actually calculated that one (I don't know how), but I did
take
> > collisions into account somewhat in my design. My dome has a safety
factor
> > of six, which I arrived at per PVHO. But what I'm doing is enclosing
that in
> > a second thinner dome which will be free-flooding. Vance Bradley made a
good
> > suggestion to me once to make the flood holes smallish, so that in case
of
> > an impact the water would exit them slowly and the second dome would act
as
> > a shock absorber. Greg Cottrell also had a suggestion for it, although
it is
> > unrelated to the collision topic... he suggested adding a UV filter to
the
> > acrylic formulation on the second dome so as to protect the thick one
inside
> > from the sun.
> >
> > cheers,
> >
> > Alec
> >
> And the best is.. it prevents the main dome from scratch during standing
> onshore..
> All the kids testing the glas hardness, all the psuber which want to
> help to lift the
> boat on the trailer .. :-)  Carsten