<html xmlns="http://www.w3.org/1999/xhtml" xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office"><head><!--[if gte mso 9]><xml><o:OfficeDocumentSettings><o:AllowPNG/><o:PixelsPerInch>96</o:PixelsPerInch></o:OfficeDocumentSettings></xml><![endif]--></head><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:16px"><div id="yui_3_16_0_ym19_1_1502885575346_3092"><br></div><div id="yui_3_16_0_ym19_1_1502885575346_3092"><span id="yui_3_16_0_ym19_1_1502885575346_3495">Here's a 2008 video documenting UC3's first dive.</span></div><div id="yui_3_16_0_ym19_1_1502885575346_3092" dir="ltr"><span id="yui_3_16_0_ym19_1_1502885575346_3299"><a href="https://www.youtube.com/watch?v=85apuqUzWCo" id="yui_3_16_0_ym19_1_1502885575346_3298" class="enhancr2_1826ea0a-eafe-236e-c225-80732297b9c9 edited-link-editor">https://www.youtube.com/watch?v=85apuqUzWCotled</a><br></span></div><div id="yui_3_16_0_ym19_1_1502885575346_3092" dir="ltr"><br></div><div id="yui_3_16_0_ym19_1_1502885575346_3092" dir="ltr">1:06 - Vessel submerges at high angle, aft first.</div><div id="yui_3_16_0_ym19_1_1502885575346_3092" dir="ltr">2:19 - Madsen operating the ballast tank valve</div><div id="yui_3_16_0_ym19_1_1502885575346_3092" dir="ltr">2:56 - Madsen orders everybody to the fore of the vessel in an attempt to level it.  The ballast tank valve lever is clearly visible here.  He also makes a curious statement..."no more about that little leak, ok?"</div><div id="yui_3_16_0_ym19_1_1502885575346_3092" dir="ltr"><br></div><div id="yui_3_16_0_ym19_1_1502885575346_3092" dir="ltr"><br></div><div id="yui_3_16_0_ym19_1_1502885575346_3092" dir="ltr">Interestingly, a video from 2009 shows the vessel is still submerging at a steep aft first attitude.  Start at 7:23</div><div id="yui_3_16_0_ym19_1_1502885575346_3092" dir="ltr"><a href="https://www.youtube.com/watch?v=zm_TRbZMzs8" id="yui_3_16_0_ym19_1_1502885575346_7895">https://www.youtube.com/watch?v=zm_TRbZMzs8</a><br></div><div id="yui_3_16_0_ym19_1_1502885575346_3092" dir="ltr"><br></div><div id="yui_3_16_0_ym19_1_1502885575346_3092" dir="ltr">This video from 2009 shows the vessel surfacing in a relatively horizontal attitude.  Start at 4:50</div><div id="yui_3_16_0_ym19_1_1502885575346_3092" dir="ltr"><a href="https://www.youtube.com/watch?v=JZX6BHMAf4w" class="enhancr2_b5dd4c3f-7645-1f0a-a318-cc6d5daa742b" id="yui_3_16_0_ym19_1_1502885575346_9838" style="background-color: rgb(255, 255, 255);">https://www.youtube.com/watch?v=JZX6BHMAf4w</a></div><div id="yui_3_16_0_ym19_1_1502885575346_9950"><br></div><div id="yui_3_16_0_ym19_1_1502885575346_9950"><br></div><div id="enhancr2_b5dd4c3f-7645-1f0a-a318-cc6d5daa742b" class="yahoo-link-enhancr-card  ymail-preserve-class ymail-preserve-style" style="max-width:400px;font-family:'Helvetica Neue', Helvetica, Arial, sans-serif;" contenteditable="false" data-url="https://www.youtube.com/watch?v=JZX6BHMAf4w" data-type="yenhancr" data-category="video" data-embed-url="https://www.youtube.com/embed/JZX6BHMAf4w?feature=oembed&autoplay=1&showinfo=0&modestbranding=1&enablejsapi=1" data-size="medium" dir="ltr"> <a href="https://www.youtube.com/watch?v=JZX6BHMAf4w" style="text-decoration:none !important; color: #000 !important;" class="yahoo-enhancr-cardlink" target="_blank" rel="noreferrer" id="yui_3_16_0_ym19_1_1502885575346_9967"> <table class="card-wrapper yahoo-ignore-table" cellpadding="0" cellspacing="0" border="0" style="max-width:400px;" id="yui_3_16_0_ym19_1_1502885575346_9966"> <tbody id="yui_3_16_0_ym19_1_1502885575346_9965"><tr id="yui_3_16_0_ym19_1_1502885575346_9964"> <td width="400" id="yui_3_16_0_ym19_1_1502885575346_9963"> <table class="card yahoo-ignore-table" cellpadding="0" cellspacing="0" border="0" width="100%" style="max-width:400px;" id="yui_3_16_0_ym19_1_1502885575346_9962"> <tbody id="yui_3_16_0_ym19_1_1502885575346_9961"><tr id="yui_3_16_0_ym19_1_1502885575346_9960"> <td class="card-primary-image-cell" style="background:#000 url('https://s.yimg.com/vv//api/res/1.2/8bbxJKCqTHPdUddY51BmQw--/YXBwaWQ9bWFpbDtmaT1maWxsO2g9MjAwO3c9NDAw/https://i.ytimg.com/vi/JZX6BHMAf4w/hqdefault.jpg.cf.jpg') no-repeat center center;background-size:cover;height:200px;position:relative;" background="https://s.yimg.com/vv//api/res/1.2/8bbxJKCqTHPdUddY51BmQw--/YXBwaWQ9bWFpbDtmaT1maWxsO2g9MjAwO3c9NDAw/https://i.ytimg.com/vi/JZX6BHMAf4w/hqdefault.jpg.cf.jpg" bgcolor="#000000" valign="top" id="yui_3_16_0_ym19_1_1502885575346_9959"> <!--[if gte mso 9]><v:rect fill="true" stroke="false" style="width:400px;height:218px;position:absolute;top:0;left:0;"><v:fill type="frame" color="#000000" src="https://s.yimg.com/vv//api/res/1.2/8bbxJKCqTHPdUddY51BmQw--/YXBwaWQ9bWFpbDtmaT1maWxsO2g9MjAwO3c9NDAw/https://i.ytimg.com/vi/JZX6BHMAf4w/hqdefault.jpg.cf.jpg"/></v:rect><![endif]--> <table class="yahoo-ignore-table" cellpadding="0" cellspacing="0" border="0" valign="top" style="width:100%;" id="yui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UC 3 
One hull sub with a bow ballastwater tank and a stern ballastwatertank. 
One ballast butterfly vale on top of each tank - tanks on the bottom open to the sea. 
Mechanical linkage from the valves to a troughhull to inside the sub to a mechanical hand lever. 
The position of this hand lever shows the position of the butterfly valve. 
Pretty simple and easy. No backup system - if you turn the two hand lever - the boat dive. 

Euronaut
One hull sub with a bow ballastwater tank and a stern ballastwatertank. 
One ballast ballvale on top of each tank - tanks on the bottom open to the sea. 
Mechanical linkage from the valves to a troughhull to inside the sub to a eletrical servo. 
Servo can be drop off in case of a electrical error and replace by a hand lever (a pipe)
Troughhull angel indicator gives you a green light if vale is closed, a red for open. 
Dashboard has four green and four red lights for the two ballast tanks valves and the 
two eletric remote controled hardtank valves. Servos only operates if you switch the converter on. 
You have to press the buttons for 15 Seconds before the ballvalves are fully open. 
This give you some time in case you can not read the labels proper and press maybe the wrong button.. 
In harbour or surface drive only mode the ball valves a sealed by metall plates -so even opening the valves will not flood the tank. These metall plates have small check screws - so you can test the vales function safe in harbour without to dive the boat. This test will be done any time before leave the harbour to ensure that both ballast valve are working. 

Problem with one hull sub with a bow ballastwater tank and a stern ballastwatertank are: 
If only one vale open and the other is still close the boat will half dive under an very heavy angle.
To prevent any mistake like that we only operate the valves only after a harbour check and only with closed hatches. 

Saftey procedure: 
What ever goes wrong with the system - first close the hatch and endsure the pressure hull tightness (seal the exhaust system).  

A submarine is only a submarine if the hatch is closed. 
In all other cases it is just a motorboat with a very low freeboard. 

vbr Carsten</pre> <div class="qtdSeparateBR" id="yui_3_16_0_ym19_1_1502885575346_3064"><br></div><div class="yahoo_quoted" id="yui_3_16_0_ym19_1_1502885575346_3071" style="display: block;"><div style="font-family: times new roman, new york, times, serif; font-size: 16px;" id="yui_3_16_0_ym19_1_1502885575346_3070"><div style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;" id="yui_3_16_0_ym19_1_1502885575346_3069"><div class="y_msg_container" id="yui_3_16_0_ym19_1_1502885575346_3074"><br><br></div>  </div> </div>  </div></div></body></html>