RE: PRV 2 was Re: [PSUBS-MAILIST]

[ronleonard <ronleonard@shaw.ca>]

That's correct Ray, though we now also have a SportSub with a top hatch,
and as David suggested, it has a bottom hatch as well, though we don't
open it for diving. It is only there as an emergency escape hatch, or to
use as an exit during the dive. Instead we open valves so the sub can
remain at ambient pressure which is much easier to do than opening a
hatch.

As an aside, we have perfected auto-hover and auto-ascent rate control
and include it as standard equipment on our ResortSub and
SurveillanceSub. This system takes over whenever the pilot releases the
controls. It stops your ascent or descent, and holds you at your current
depth until you again take the controls. It also prevents you from
ascending or descending faster than 1 foot per second. There is also a
target depth mode where you can program your target depth and the sub
will ascend or descend to that depth and stop when it gets there... Very
cool. For example, you release the controls at 75 feet to check your
gauges. The sub will automatically stop at 75 feet and will hold there.
You decide to end your dive early, but want to stop at 10 feet to check
for surface traffic before surfacing, so you program a target depth of
10 feet. The sub will ascend, at less than 1 foot per second, until it
reaches 10 feet at which point it stops and holds 10 feet. In actual
fact it decelerates prior to reaching 10 feet so as not to overshoot. 

It makes piloting a SportSub a totally different experience... The
marvels of technology!

Ron 


-----Original Message-----
From: owner-personal_submersibles@psubs.org
[mailto:owner-personal_submersibles@psubs.org] On Behalf Of Ray Keefer
Sent: February 14, 2002 4:38 PM
To: personal_submersibles@psubs.org
Subject: Re: PRV 2 was Re: [PSUBS-MAILIST]


Hi Dave,

Most of the ambient dry and semi-dry subs that I know of have a bottom
entry. SportSub for instance is a semi-dry sub that you enter into from
underneath.

Regards,
Ray

> X-Sender: buchner@wcta.net (Unverified)
> Date: Thu, 14 Feb 2002 16:18:24 -0600
> To: personal_submersibles@psubs.org
> From: David Buchner <buchner@wcta.net>
> Subject: Re: PRV 2 was Re: [PSUBS-MAILIST]
> Content-Transfer-Encoding: 8bit
> X-MIME-Autoconverted: from quoted-printable to 8bit by whoweb.com id 
> RAA17003
> 
> At 17:06 +0100 2/12/02, Carsten Standfuß wrote:
> >Hmm - No Top-hatch.. only accessible
> >from the bottom hatch. You need diving
> >equipment or an small Offshore supply boat
> >with an A-Mast crane to get inside..
> >
> >A cheap one should be around 150.000 USD.
> >Maybe to assamble a top hatch is cheaper.
> 
> I've wondered about this. In ambient-pressure subs that are "bubbles,"

> do the
occupants usually have to swim in from the bottom? Or do you have to
seal a 
hatch in the bottom, enter through the top, seal the top hatch, and then
open 
the bottom one before diving? I mean, otherwise it'd just sink like a
regular 
boat with a hole in the bottom, right?
> 
> Or do they have big enough MBT's that they float even with an open top

> and
bottom hatch? Or aren't there enough boats like this for there to BE a
way it's 
"usually" done?
> --
> 
> 
> David
> buchner@wcta.net - MN, USA
> http://customer.wcta.net/buchner