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</o:shapelayout></xml><![endif]--></head><body lang=EN-CA link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Just to add a complication to the project, you will need to have the vent accessible by someone on the outside too, in case the sub has surfaced but the operator is incapacitated.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Tim<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri",sans-serif'> Personal_Submersibles [mailto:personal_submersibles-bounces@psubs.org] <b>On Behalf Of </b>Alan via Personal_Submersibles<br><b>Sent:</b> Saturday, December 30, 2017 12:51 PM<br><b>To:</b> Personal Submersibles General Discussion <personal_submersibles@psubs.org><br><b>Subject:</b> Re: [PSUBS-MAILIST] Hatch Closure Mechanism<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Thanks Hank,<o:p></o:p></p></div><div id=AppleMailSignature><p class=MsoNormal>will have to think on this one. I want to let a novice dive my sub, so<o:p></o:p></p></div><div id=AppleMailSignature><p class=MsoNormal>the system needs to be bullet proof.<o:p></o:p></p></div><div id=AppleMailSignature><p class=MsoNormal>If I have some sort of lock mechanism I would need to be able to bypass<o:p></o:p></p></div><div id=AppleMailSignature><p class=MsoNormal>it if I needed to escape at depth. The pressure at depth would be apposing <o:p></o:p></p></div><div id=AppleMailSignature><p class=MsoNormal>the manual operation of the overpressure valve. You could flood the sub first<o:p></o:p></p></div><div id=AppleMailSignature><p class=MsoNormal>but normally the hatch is un-dogged prior to the hull equalizing.<o:p></o:p></p></div><div id=AppleMailSignature><p class=MsoNormal>Cheers Alan<o:p></o:p></p></div><div id=AppleMailSignature><p class=MsoNormal><o:p> </o:p></p></div><div id=AppleMailSignature><p class=MsoNormal><br><br>Sent from my iPad<o:p></o:p></p></div><div><p class=MsoNormal style='margin-bottom:12.0pt'><br>On 31/12/2017, at 1:49 AM, hank pronk via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<o:p></o:p></p></div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif'>Alan,<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif'>You could have a lock that prevents the hatch mechanism from opening that is activated by turning the hatch vent. I always vent before I one the hatch anyways.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif'>Hank<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif'><o:p> </o:p></span></p></div><div id="yahoo_quoted_4704983245"><div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'>On Friday, December 29, 2017, 11:09:03 PM MST, Alan via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote: <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'><o:p> </o:p></span></p></div><div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'>Just doing some evening reading of the GL rules & noticed this rule about hatches....<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'>"the closing mechanism is to be designed in such a way that opening of<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'>the hatch is only possible after pressure equalisation" <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'>I am wondering what options there are for achieving this.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'>Has anyone had experience of the hatch opening with explosive force due<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'>to internal over-pressure not being equalised.<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'>Alan <o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'>Sent from my iPad<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'><o:p> </o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'>_______________________________________________<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'>Personal_Submersibles mailing list<o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'><a href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><o:p></o:p></span></p></div><div><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Helvetica",sans-serif;color:#26282A'><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><o:p></o:p></span></p></div></div></div></div></div></div></blockquote><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal>_______________________________________________<br>Personal_Submersibles mailing list<br><a href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><o:p></o:p></p></div></blockquote></div></body></html>