Yes sir, as I told Rick in my little dissertation there, the idea may prove impractical at that size for that very reason. I am sure I can build a hull and systems but I can't make the gas laws do what I want.
I am still playing with ballast and control issues
Joe
From: Myles Hall <myles.h@sasktel.net>
Reply-To: personal_submersibles@psubs.org
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] Re: Preliminary calculations, please check me
Date: Sun, 30 Oct 2005 12:45:44 -0600
Joe,It appears to me that if you are considering an ambient design that also has large ballast capacity, you are going to have to carry a ton of on board compressed air. That seems to be the issue with ambient designs.Myles.----- Original Message -----From: Joseph PerkelSent: Sunday, October 30, 2005 11:50 AMSubject: [PSUBS-MAILIST] Re: Preliminary calculations, please check me************************************************************************ ************************************************************************ ************************************************************************ The personal submersibles mailing list complies with the US Federal CAN-SPAM Act of 2003. Your email address appears in our database because either you, or someone you know, requested you receive messages from our organization. If you want to be removed from this mailing list simply click on the link below or send a blank email message to: removeme-personal_submersibles@psubs.org Removal of your email address from this mailing list occurs by an automated process and should be complete within five minutes of our server receiving your request. PSUBS.ORG PO Box 311 Weare, NH 03281 603-529-1100 ************************************************************************ ************************************************************************ ************************************************************************Myles,
I am sitting here trying to make sense of some numbers but you may be interested in this as you are interested in the same basic dimensions I am.
According to the NAVPERS manual a Gato class fleet boat had a surface displacement of 1,750 tons and submerged 2,228 tons at neutral trim. The MBT were 16% of trim at 359 tons, not counting fuel tanks which were always full of either D.O. or seawater. There is a difference of some 28% between surface displacement and neutral.
I do not yet know how this scales down but I am trying to figure out some basics here, like tank size and air requirements. I see widely varying numbers in different submersibles.
If I have to double the cabin air to maintain a dry ambient boat @ 33', I may have to rethink an open bottom design.
I am finding lots of stability considerations as well.
Joe
From: Myles Hall <myles.h@sasktel.net>
Reply-To: personal_submersibles@psubs.org
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] Re: Preliminary calculations, please check me
Date: Sun, 30 Oct 2005 11:11:19 -0600
Joe,I'm sure it's all dependant on what you want the sub to do. For me, I want something with decent surface running so that I can drive the thing to the dive location. With this in mind, I am looking for quite a bit of ballast bouyancy to get as much of the boat out of the water as I can to reduce the drag. I am looking to have my dive planes up high on the hull so that they clear the water as well when in surface trim.However, I figure if you just want enough ballast to get you sufficient free board, you could get away with considerably less than 40%.Myles.----- Original Message -----From: Joseph PerkelSent: Sunday, October 30, 2005 6:38 AMSubject: [PSUBS-MAILIST] Re: Preliminary calculations, please check me************************************************************************ ************************************************************************ ************************************************************************ The personal submersibles mailing list complies with the US Federal CAN-SPAM Act of 2003. Your email address appears in our database because either you, or someone you know, requested you receive messages from our organization. If you want to be removed from this mailing list simply click on the link below or send a blank email message to: removeme-personal_submersibles@psubs.org Removal of your email address from this mailing list occurs by an automated process and should be complete within five minutes of our server receiving your request. PSUBS.ORG PO Box 311 Weare, NH 03281 603-529-1100 ************************************************************************ ************************************************************************ ************************************************************************Thanks Paul and Myles,
30 to 45% is quite a bit, I am still working the numbers to see if this is doable.
Joe
From: Paul Kreemer <paulkreemer@gmail.com>
Reply-To: personal_submersibles@psubs.org
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] Preliminary calculations, please check me
Date: Sat, 29 Oct 2005 18:50:07 -0700
Yes, using 63 lb/cf of seawater gives about 16cf needed to weigh 1000lb.
I think a WWII style boat which was more on the surface than submerged would have 30% or more reserve buoyancy. Like Myles says.
On 10/29/05, Myles Hall <myles.h@sasktel.net> wrote:Joe,My design calls for about 45%. Iwant to get that thing out of the water when surface running. Also, I figure a guy needs all the bouyancy he can get when launching the thing so that you don't need 6' of water. I'm going for the "better to have too much than not enough" concept. Hopefully I'm not overlooking something.Myles.