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</o:shapelayout></xml><![endif]--></head><body lang=EN-CA link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>Hank,<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><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>The aircraft compass may be the answer. The difficulty is that the steel hull is deflecting the natural magnetic lines of the earth. Steel ships get over this to a certain extent by degaussing the ship. This is likely not an option. I read somewhere that WWII subs could not us a magnetic compass at all, but rather used a directional gyro. The cheaper aircraft direction gyro's are vacuum powered, but there are electrical powered dg's available. You would not need a flight certified one. EBay has a few but most don't say whether they are vacuum or electric.<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><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D;mso-fareast-language:EN-US'>What do the others with the K-subs use? What does Phil install in the larger passenger (Aquarius) subs?<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><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 0cm 0cm 0cm'><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>hank pronk via Personal_Submersibles<br><b>Sent:</b> July-31-15 3:18 AM<br><b>To:</b> Personal Submersibles General Discussion <personal_submersibles@psubs.org><br><b>Subject:</b> [PSUBS-MAILIST] compass<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div id="yui_3_16_0_1_1438337398118_3173"><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:"Helvetica",sans-serif;color:black'>Tim,<o:p></o:p></span></p></div><div id="yui_3_16_0_1_1438337398118_3173"><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:"Helvetica",sans-serif;color:black'>I am all ears about the aircraft compass, any suggestions? I don't get why it is not working, I can rotate the compass body and the ball inside stays fixed on the direction. When I travel on the bottom at 270 degrees, I deviate and correct and I expect to loosely track but maintain my direction. When I surface I am facing the opposite direction. Hmmm I wonder if the sub is rotating during the assent, that would make sense. I will have to watch the compass while I am surfacing, maybe the sub develops a spin.<o:p></o:p></span></p></div><div id="yui_3_16_0_1_1438337398118_3173"><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:"Helvetica",sans-serif;color:black'>Hank<o:p></o:p></span></p></div></div></div></body></html>