<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> If that's true, then I should immediatly throw out my 2 lb life preserver that wraps around my upper torso, and allows my 200 lb body, to remain afloat. I believe 2/200 comes out to 1%. <br /> Posted by kyle_baron</DIV></p><p>Not applicable. The human body is mostly water and can float without any assistance in the first place. The life preserver just insures that the head and nose is out of the water. The SRB is much more dense and would require more assistance. We can shoot down your ideas all day long when you keep ignoring the laws of nature. Learn something about the basic physics involved, this has nothing to do with rocket science. There are many websites on launch vehicles. </p><p> </p><p>Also the non tank volumes of Ares I, interstage, spacecraft adapter, forward adapter, etc are not sealed and would take on water. Also, there is no need for them to be air tight and are have vents to allow air to escape during ascent. </p>
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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>And that's all I wanted to show, at this time. Thank you. By avoiding ignition with the nozzle obstructed, do you mean a secondary explosion? And how is that avoided? <br />Posted by kyle_baron</DIV></p><p>The explosion is not what I would call secondary. You avoid it by not igniting under water,<br /></p> <div class="Discussion_UserSignature"> </div>
<p>It is possible to launch rockets from a submerged launch platform. But it is not possible to launch an SRB submerged. You need a rocket which was designed specifically for that mission. It's a waste of effort to redesign SRB to do it; you'd be much better off starting from scratch.</p><p>The Volna rocket has had some commercial success in satellite launches, firing from Russian Navy submarines in the Barents Sea. There have been failures, though I suspect this is not because of any fundamental problems with the concept but rather with the modifications made to make it serve a new, non-lethal mission. A related concept, though it is not submerged, is the Sea Launch platform, which launches Zenit 3SL rockets from a converted mobile oil drilling platform, generally from points on the equator out in the Pacific Ocean. It does feature a flame deflector, and that deflector suffered considerable damage when a Zenit rocket fell into it and exploded not too long ago. (The damage was repairable, and Sea Launch has had a successful return to flight since then.) </p><p>Actually, Sea Launch is much closer to the intent of the Sea Dragon concept than the Volna is. The real point of Sea Dragon was not to launch submerged but to allow them to launch from any latitude they might choose without the exorbitant expense of building a new launch complex. Sea Dragon was an interesting concept, but the rockets involved were gargantuan. Ultimately, it died of the same thing as Saturn V: no whopping huge payloads to justify it, and no development funds, as NASA's budget was being scaled back in the face of mounting Vietnam War spending and declining public interest in manned spaceflight once the American flag had been planted on the Moon. I mean, they even cancelled Saturn V. They weren't going to fund Truax to finish the Sea Dragon concept, not in that political environment. 
</p> <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em> -- The Tenth Doctor, "Blink"</font></p> </div>
</p> <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em> -- The Tenth Doctor, "Blink"</font></p> </div><p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Not applicable. The human body is mostly water and can float without any assistance in the first place.</DIV></p><p> </p><p>Only if your moving your arms and legs. Have you ever been in the water? And I think it's an excellent analogy. The upper torso, with the ballast of air in the lungs = the 2nd stage (with the foam insulation + the large quantity of very light LH2). The legs (with little or no ballast) = the SRB.</p><p> </p><p> Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> Also the non tank volumes of Ares I, interstage, spacecraft adapter, forward adapter, etc are not sealed and would take on water. Also, there is no need for them to be air tight and are have vents to allow air to escape during ascent. <br />Posted by Cygnus_2112</DIV></p><p> </p><p>I won't question your authority here, except to say that changes could be made, to seal those sections, which could then act as ballast. I suppose the reason the vents are there, is a pressure build up at higher altitudes.<br /></p> <div class="Discussion_UserSignature"> <p><font size="4"><strong></strong></font></p> </div>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>It is possible to launch rockets from a submerged launch platform. But it is not possible to launch an SRB submerged. You need a rocket which was designed specifically for that mission. <br />Posted by CalliArcale</DIV></p><p> </p><p>Correct, in it's current state. However, the Sea Bee was a modified Aerobee solid rocket:</p><p> </p><p>http://en.wikipedia.org/wiki/Aerobee_%28rocket%29</p><p> </p><p>The rocket was two stage with a solid-fuel boost and a nitric acid/aniline sustainer.<br /></p> <div class="Discussion_UserSignature"> <p><font size="4"><strong></strong></font></p> </div>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> Correct, in it's current state. However, the Sea Bee was a modified Aerobee solid rocket: http://en.wikipedia.org/wiki/Aerobee_%28rocket%29The rocket was two stage with a solid-fuel boost and a nitric acid/aniline sustainer. <br /> Posted by kyle_baron</DIV></p><p> </p><p>No, the Seebee was only the liquid upperstage of the Aerobeee </p>
<p>OK, I was reading the posts here and have come up with a theory of my own. Why can't we avoind the whole water problem and mimic the bouyancy part on dry land? Wouldn't it erase alot of the issues? </p><p> I was thinking if you had some gigantic springs, like 10 stories high or so, and scrunched them down all the way, and then brought in the rocket and set it on top of them, or maybe first set the rocket on top of them to help push them down. Then you could push on the top of the rocket and keep pushing until the springs get into some sort of locked position that we created. Henceforth, when we are ready to launch, we simply press a button releasing the springs which would catapult the rocket into the air, then we would be able to fire up the boosters while we were going up and take off. It'd save us alot of fuel I'd think. I was actually looking at a toy and wondering why we wouldn't be able to use this concept on rockets.</p><p> And if that would be plausible, then what if we could get even bigger springs that would be able to spring the rocket right into space? I'm thinking this probably wouldn't work because the initial g-force would probably be massive. What do you guys think? It would cost us nothing for power. We could just keep winding up the springs and popping the rockets into space non-stop.</p> <div class="Discussion_UserSignature"> <p><em><font color="#0000ff">______________</font></em></p><p><em><font color="#0000ff">Caution, I may not know what I'm talking about.</font></em></p> </div>
<p>Just an observation:</p><p>Water has a drag effect. Besides having to use specially constructed launch cannisters, you'd also have to streamline them and even with that, you're still going to lose much, much more energy spent on counteracting the drag effect of water than you would fighting it while airborne. Bouyancy isn't going to get you anything appreciable as you're max rate of ascent is going to be pretty crappy due to drag no matter how "needlike" you make it. It will not exponentially increase in appreciable amounts simply due to depth of release. There are ways to combat drag in such situations but they are very expensive and would be a complete waste in these situations because they're designed for powered submerged vehicles. I don't see any advantages using an underwater system that couldn't be attained cheaper and more efficiently on the surface. </p> <div class="Discussion_UserSignature"> <font size="1">I put on my robe and wizard hat...</font> </div>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>OK, I was reading the posts here and have come up with a theory of my own. Why can't we avoind the whole water problem and mimic the bouyancy part on dry land? Wouldn't it erase alot of the issues? I was thinking if you had some gigantic springs, like 10 stories high or so, and scrunched them down all the way, and then brought in the rocket and set it on top of them, or maybe first set the rocket on top of them to help push them down. Then you could push on the top of the rocket and keep pushing until the springs get into some sort of locked position that we created. Henceforth, when we are ready to launch, we simply press a button releasing the springs which would catapult the rocket into the air, then we would be able to fire up the boosters while we were going up and take off. It'd save us alot of fuel I'd think. I was actually looking at a toy and wondering why we wouldn't be able to use this concept on rockets. And if that would be plausible, then what if we could get even bigger springs that would be able to spring the rocket right into space? I'm thinking this probably wouldn't work because the initial g-force would probably be massive. What do you guys think? It would cost us nothing for power. We could just keep winding up the springs and popping the rockets into space non-stop. <br />Posted by trumptor</DIV></p><p>That would be the equivalent of an impulsive burn in rocketry -- an ideal case in which you burn all of the propellant instantaneously and then coast. It has the advantage of eliminating what are called gravitatinal losses (losses from having to lift propellant during a burn of finite duration). It has the disadvantage of incurring much higher aerodynamic losses since you hit maximum velocity at launch in the densest part of the atmosphere.</p><p>But most importantly it applies enormous acceleration loads. If you actually tried in practice to do what you suggest it would be like shooting the payload out of a cannon with sufficient velocity to reach orbit. Virtually nothing, certainly not humans, would survive. You can forget about satellites also. </p> <div class="Discussion_UserSignature"> </div>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>That would be the equivalent of an impulsive burn in rocketry -- an ideal case in which you burn all of the propellant instantaneously and then coast. It has the advantage of eliminating what are called gravitatinal losses (losses from having to life propellant during a burn of finite duration). It has the disadvantage of incurring much higher aerodynamic losses since you hit maximum velocity at launch in the densest part of the atmosphere.But most importantly it applies enormous acceleration loads. If you actually tried in practice to do what you suggest it would be like shooting the payload out of a cannon with sufficient velocity to reach orbit. Virtually nothing, certainly not humans, would survive. You can forget about satellites also. <br />Posted by DrRocket</DIV></p><p>It would be excatly like Project Babylon: http://en.wikipedia.org/wiki/Project_Babylon</p><p>A gigant cannon to shoot satellites up to orbit. And of course it failed... If we are talking alternative launch consepts I'd prefer some sort of maglev train as a first stage: http://en.wikipedia.org/wiki/Launch_loop</p><p>But now we are slipping from the original topic of the water launch...<br /></p> <div class="Discussion_UserSignature"> </div>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> 2. Mods allowing submergence would make it heavier. <br />Posted by Cygnus_2112</DIV></p><p> </p><p>Ok, you've convinced me that it isn't practical at this time, for Ares I. Do I hear champagne corks popping? And I thought I heard a couple of party poppers going off. <img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-tongue-out.gif" border="0" alt="Tongue out" title="Tongue out" /></p><p> </p><p>I would like to change the focus to Ares V, because of it's weight, (11metric tons overweight) and noise issues. Can Ares V launch from underwater (with modifications) similar to what was proposed with Sea Dragon?</p> <div class="Discussion_UserSignature"> <p><font size="4"><strong></strong></font></p> </div>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> Ok, you've convinced me that it isn't practical at this time, for Ares I. Do I hear champagne corks popping? And I thought I heard a couple of party poppers going off. I would like to change the focus to Ares V, because of it's weight, (11metric tons overweight) and noise issues. Can Ares V launch from underwater (with modifications) similar to what was proposed with Sea Dragon? <br /> Posted by kyle_baron</DIV></p><p>No, because it use solid rocket booster and there still is no advantage. Sea Dragon was to be a empty liquid fueled vehicle, so big that it was to be handled like ship. The water didn't give Sea Dragon a performance advantage, it was for ease of handling. </p><p>Also the LSAM would not take too lightly to the sea environment. </p>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>No, because it use solid rocket booster and there still is no advantage. Sea Dragon was to be a empty liquid fueled vehicle, so big that it was to be handled like ship. The water didn't give Sea Dragon a performance advantage, it was for ease of handling. Also the LSAM would not take too lightly to the sea environment. <br />Posted by Cygnus_2112</DIV></p><p><font size="1">The sea based launch for the Saturn V was a concept looked at during it's early stages of development. I thing the subject was touched upon in 'Chariots for Apollo'. It was even proposed to have the VAB accessed by canals, and then float the entire assembly out to sea to the launch area. A few problems such as tides, salt water corrosion, steering the launch barges in the lightest of winds, put a very quick end to any sea launch proposals for such a massive rocket. With the rocket and umbillical tower presenting a sail area to the wind as great as that of a windjammer, the crawler concept took first place honours.</font></p><p><font size="1">Gaz</font></p><p><br /><br /> </p> <div class="Discussion_UserSignature"> </div>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>The sea based launch for the Saturn V was a concept looked at during it's early stages of development. I thing the subject was touched upon in 'Chariots for Apollo'. It was even proposed to have the VAB accessed by canals, and then float the entire assembly out to sea to the launch area. A few problems such as tides, salt water corrosion, steering the launch barges in the lightest of winds, put a very quick end to any sea launch proposals for such a massive rocket. With the rocket and umbillical tower presenting a sail area to the wind as great as that of a windjammer, the crawler concept took first place honours.Gaz <br />Posted by freya</DIV></p><p>There is quite a difference between launching at sea and launching under the sea. For some systems there may be advantages to being able to launch from a floating platform that can be positioned at an advantageous location.</p><p>There is no performance advantage from launching from beneath the sea. It doesn't matter what the propulsion system is, liquid, solid, nuclear, ... The reason that submarines launch SLBMs from under water has to do with protection of the boat and has nothing to do with improved performance of the missile. And those missiles do not ignite while submerged. And with solids, in which pressure increases burn rate and hence mass flow rate, ignition while submerged will be catastrophic unless the grain is specifically tailored to prevent that occurrence -- and performance would be decreased by any such tailoring. If such were not the case, SLBMs would ignite under water, as they are very much driven by performance -- the greater the range of an SLBM the more water is available in which to hide the submarine. </p> <div class="Discussion_UserSignature"> </div>
<p> I would like to change the focus to Ares V, because of it's weight, (11metric tons overweight) and noise issues. Can Ares V launch from underwater (with modifications) similar to what was proposed with Sea Dragon? <br /> Posted by kyle_baron[/QUOTE]</p><p><font size="2">I can see some problems keeping the SRB's attached to the core. All that water resistance would pose some truely nightmarish engineering issues to keep the combination in one piece.</font></p> <div class="Discussion_UserSignature"> </div>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> I would like to change the focus to Ares V, because of it's weight, (11metric tons overweight) and noise issues. Can Ares V launch from underwater (with modifications) similar to what was proposed with Sea Dragon? Posted by kyle_baron</DIV>I can see some problems keeping the SRB's attached to the core. All that water resistance would pose some truely nightmarish engineering issues to keep the combination in one piece. <br />Posted by MarkStanaway</DIV></p><p>yeah. The SRBs will probably become detached when they blow up.<br /></p> <div class="Discussion_UserSignature"> </div>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>No, because it use solid rocket booster and there still is no advantage. Sea Dragon was to be a empty liquid fueled vehicle, so big that it was to be handled like ship. The water didn't give Sea Dragon a performance advantage, it was for ease of handling.</DIV></p><p> </p><p>Understood. I'm not looking for an advantage, like in Ares I. I'm looking to see if a water based launch (with it's inefficiencies) would over come a land based launch, for the problems of weight and noise.</p><p> </p><p> Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> Also the LSAM would not take too lightly to the sea environment. <br />Posted by Cygnus_2112</DIV></p><p> </p><p>I was hoping that would be above the water line, otherwise, the rocket would be completly submerged.<br /></p> <div class="Discussion_UserSignature"> <p><font size="4"><strong></strong></font></p> </div>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>yeah. The SRBs will probably become detached when they blow up. <br />Posted by DrRocket</DIV></p><p> </p><p>Why would the SRB's on Ares V have to ignite along with the core? couldn't it be delayed until it's out of the water?<br /></p> <div class="Discussion_UserSignature"> <p><font size="4"><strong></strong></font></p> </div>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> I can see some problems keeping the SRB's attached to the core. All that water resistance would pose some truely nightmarish engineering issues to keep the combination in one piece. <br />Posted by MarkStanaway</DIV></p><p> </p><p>A cap over the nose cone of the SRB, and attached to the core, should do it. That might even create some ballast, under the cap.</p> <div class="Discussion_UserSignature"> <p><font size="4"><strong></strong></font></p> </div>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> With the rocket and umbillical tower presenting a sail area to the wind as great as that of a windjammer, the crawler concept took first place honours.Gaz <br />Posted by freya</DIV></p><p> </p><p>What do you mean by umbillical tower?<br /></p> <div class="Discussion_UserSignature"> <p><font size="4"><strong></strong></font></p> </div>
Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> Why would the SRB's on Ares V have to ignite along with the core? couldn't it be delayed until it's out of the water? <br /> Posted by kyle_baron</DIV>I think one of the pros said that the SRBs can't be carried up by the rest of the structure. That was in the air, so if I understand correctly, in water the strain would be that much greater.<br /> <div class="Discussion_UserSignature"> </div>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> Why would the SRB's on Ares V have to ignite along with the core? couldn't it be delayed until it's out of the water? <br /> Posted by kyle_baron</DIV></p><p>With the initial thrust being supplied by the core the situation would be worse because the SRB's would be pure drag on the combination and would probably be ripped off and left on the seabed.</p> <div class="Discussion_UserSignature"> </div>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> Why would the SRB's on Ares V have to ignite along with the core? couldn't it be delayed until it's out of the water? <br /> Posted by kyle_baron</DIV></p><p> </p><p>The core can't lift itself much less the unignited SRB's </p>
<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> What do you mean by umbillical tower? <br />Posted by kyle_baron</DIV></p><p> <font size="1">The 'Launch Umbilical Tower'. </font><br /></p> <div class="Discussion_UserSignature"> </div>
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