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<div dir="ltr" data-setdir="false">Alan, I know after laughing Gamma I always gave a boat of air to make sure all was open and good. I could not quantify the amount but know there is not much difference.</div><div dir="ltr" data-setdir="false">Hank</div><div><br></div>
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On Monday, May 18, 2020, 6:00:12 PM MDT, Alan via Personal_Submersibles <personal_submersibles@psubs.org> wrote:
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<div><div dir="ltr">Just did some experiments & answered my own question.<br clear="none">If you put an upturned glass in a container full of water & push it down till<br clear="none">it is just fully under the surface, the water enters the bottom of the glass to<br clear="none">a level that is 6% of the volume of the glass.<br clear="none">This is less than what I thought. You would only gain 6% more floatation by<br clear="none">going from a free flooding ballast to having a flood valve.<br clear="none">The pros of having a flood valve are the added floatation & added security that <br clear="none">your sub won't sink if the vent valve fails.<br clear="none">The cons are that you would need a much larger valve than the vent valve <br clear="none">& there would be more pressure in the ballast tank when blowing the ballast.<br clear="none">Alan<br clear="none"><br clear="none">> On 18/05/2020, at 7:45 AM, Alan via Personal_Submersibles <<a shape="rect" ymailto="mailto:personal_submersibles@psubs.org" href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<br clear="none">> <br clear="none">> Has anybody got an idea or guess as to how much water comes in to<br clear="none">> a free flooding ballast tank? Ie. would it fill up to 1/4 of the volume<br clear="none">> of the tank with water? And does this vary much after towing.<br clear="none">> Also if you know the volume of your ballast tank that would be helpful.<br clear="none">> Am considering inlet valves at the bottom of the tanks as I will be towing <br clear="none">> the sub a lot.<br clear="none">> Thanks Alan<br clear="none">> _______________________________________________<br clear="none">> Personal_Submersibles mailing list<br clear="none">> <a shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none">> <a shape="rect" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><div class="yqt6416860983" id="yqtfd39455"><br clear="none"><br clear="none"><br clear="none">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a shape="rect" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div></div></div>
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