<html><head></head><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px"><div id="yui_3_16_0_ym19_1_1465942482515_3098"><span>Alan,</span></div><div dir="ltr" id="yui_3_16_0_ym19_1_1465942482515_3097">I am not getting that feeling. I know what you mean, my little yellow sub had that problem. i still think it has to do with the small air line going to witch ever tank has the least resistance of the two</div><div dir="ltr" id="yui_3_16_0_ym19_1_1465942482515_3097">. But you could be right?</div><div dir="ltr" id="yui_3_16_0_ym19_1_1465942482515_3097">Hank</div> <div class="qtdSeparateBR"><br><br></div><div class="yahoo_quoted" style="display: block;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 12px;"> <div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;"> <div dir="ltr"><font size="2" face="Arial"> On Tuesday, June 14, 2016 4:05 PM, Alan James via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<br></font></div> <br><br> <div class="y_msg_container"><div id="yiv4515741213"><div><div style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"><div><span>Hank,</span></div><div dir="ltr" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2820"><span id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2819">am wondering if the instability has anything to do with the change</span></div><div dir="ltr" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2822"><span id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2821">in metacentric height.</span></div><div dir="ltr" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2830"><span id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2836"><a rel="nofollow" shape="rect" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2835" target="_blank" href="http://maritime.org/doc/fleetsub/chap5.htm">http://maritime.org/doc/fleetsub/chap5.htm</a></span></div><div id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2921"> It is possible to design a ballast system where you are stable on</div><div dir="ltr" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2920">the surface & stable under the water, but during the transitions the</div><div dir="ltr" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2919">center of buoyancy goes below the center of gravity & leaves the sub</div><div dir="ltr" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2918">vulnerable to flipping upside down.</div><div dir="ltr" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2970"> It could be that at this point of transition if the center of buoyancy &</div><div dir="ltr" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_3010">center of gravity come close, then any slight weight imbalance from one</div><div dir="ltr">side to the other of the centerline of the sub is magnified. </div><div dir="ltr">You could always use your vertical thrusters to help control things in</div><div dir="ltr" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_3091">the mean time.</div><div dir="ltr" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_3092">Cheers Alan<br clear="none"></div><div id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2870"><br clear="none"></div><div dir="ltr" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2823"><span></span><br clear="none"></div><div class="yiv4515741213qtdSeparateBR" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2731"><br clear="none"><br clear="none"></div><div class="yiv4515741213yahoo_quoted" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2741" style="display:block;"> <div id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2740" style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"> <div id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2739" style="font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px;"> <div class="yiv4515741213yqt4502021904" id="yiv4515741213yqt19175"><div dir="ltr" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2738"> <font id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2737" face="Arial" size="2"> </font><hr id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2736" size="1"> <b><span style="font-weight:bold;">From:</span></b> hank pronk via Personal_Submersibles <personal_submersibles@psubs.org><br clear="none"> <b><span style="font-weight:bold;">To:</span></b> Personal Submersibles General Discussion <personal_submersibles@psubs.org> <br clear="none"> <b id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_3094"><span id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_3093" style="font-weight:bold;">Sent:</span></b> Wednesday, June 15, 2016 8:20 AM<br clear="none"> <b><span style="font-weight:bold;">Subject:</span></b> [PSUBS-MAILIST] Dive report<br clear="none"> </div> <div class="yiv4515741213y_msg_container" id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2803"><br clear="none"><div id="yiv4515741213"><div id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2802"><div id="yiv4515741213yui_3_16_0_ym19_1_1465940179022_2801" style="color:rgb(0, 0, 0);font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:12px;background-color:rgb(255, 255, 255);"><div id="yiv4515741213yui_3_16_0_ym19_1_1465934153015_2634">First time ever ( I think) that I was able to dive on the first test trip. I had to pull the sub out of the water onto the ramp to remove my new weight from the front. Then add 4 big rocks from shore in the back end, and off I went. The Perry thrusters work okay but one is making noise in reverse, it is the one that has the original spring seal. I will put the new cartridge seal in it now. Amazingly they only draw 14 amps at full speed and that is for both, maybe my amp meter is wrong. The sub is very slow to react to coarse correction, when travelling strait ahead I can stop one motor and it keeps going strait for a long way, I have to reverse one motor while underway to turn. I should have mounted them in the back on an angle, I did testing last year and the worked well. Having them strait is less responsive. When I launch the sub it sits nice and level and higher as expected, the sub is very stable. BUTTTT when I start to dive the sub lists bad to one side, once I am submerged it is fine and I can cruise around like always. When I surface the sub has a bad list again???? I have to get out and shift my weight to the high side and wait for the sub to level out. Once level it stays level and is stable again. Weird!!! I have a common vent for both front and common vent for both rear tanks. I think the air is taking the path of least resistance to one side and when I surface the one side is high and the air spills out the bottom instead of filling the low side tanks. I am not sure how to fix this easily, any ideas are welcome. Worst case, I can add air lines to each side, yuk! there has to be a simple fix.</div><div id="yiv4515741213yui_3_16_0_ym19_1_1465934153015_2634">I guess lengthening the pipes under the tanks would help, the air would have to go deeper forcing it to the opposite side.</div><div id="yiv4515741213yui_3_16_0_ym19_1_1465934153015_2634">I met some nice people and had a nice visit. My trailer handles the weight okay but my truck feels it. Might have to get a kick ASS truck like Tim has with a nice rattling diesel. All and all a good first dive.</div><div id="yiv4515741213yui_3_16_0_ym19_1_1465934153015_2634">Hank</div></div></div></div><br clear="none">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org" target="_blank" href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a rel="nofollow" shape="rect" target="_blank" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"><br clear="none"><br clear="none"></div></div> </div> </div> </div></div></div></div><br><div class="yqt4502021904" id="yqt46631">_______________________________________________<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><br><br></div> </div> </div> </div></div></body></html>