Heavy Lift?

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john_316

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Ok I like the idea of the new Heavy Delta IV with the 3 core boosters.<br /><br />But would the Delta IV or the Atlas 5 be like if it had either the Titan SRB's or STS SRBs attached to them as well or in lieu of the 2 core boosters?<br /><br />Would it provide more lifting capacity or would the addition be negligable? <br /><br />
 
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najab

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><i>But would the Delta IV or the Atlas 5 be like if it had either the Titan SRB's or STS SRBs attached to them as well or in lieu of the 2 core boosters?</i><p>Someone asked about Shuttle SRBs before the crash...I don't have the numbers here now, but at liftoff the stack would leap off the pad with an acceleration of about 5Gs, shoot up like a bat out of hell, accelerating all the way and break up when the Gs reached the point that the Atlas/Delta core simply crumbled. That's assuming that the SRBs didn't simply fly off leaving the core on the pad.<p>Titan SRM's I don't know about.</p></p>
 
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halman

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najaB,<br /><br />One is inclined to wonder just how much mass a Delta or Atlas core can carry without redesign. We can strap boosters on until the thing looks like the Texas A & M bonfire stack, but that does not mean that the vehicle can carry more mass. I think people should keep in mind that both of those launch vehicles were desinged primarily for satellite launches, which may be why the payload shrouds seem so big in comparision to the vehicle core. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>
 
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propforce

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<i> "..... but at liftoff the stack would leap off the pad with an acceleration of about 5Gs, shoot up like a bat out of hell, accelerating all the way and break up when the reached the point that the Atlas/Delta core simply crumbled. That's assuming that the SRBs didn't simply fly off leaving the core on the pad. ....."</i><br /><br />That's the conventional mistake most folks make. In reality, if this concept is to be taken seriously, engineers will look into beef up the core structures to handle the increased thrust and acceleration. You do this with every bit of upgrade irregardless. <br /><br />This concept also allow a different way to fly. For example, one can delay ingniting the core engine(s) until right before the SRB burn-out, thus making the core a 1.5 stage. This may significantly boost (pun-intended <img src="/images/icons/wink.gif" />) payload performance.<br /><br /><br /> <div class="Discussion_UserSignature"> </div>
 
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mikejz

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Why stop at strap-ons. Just cluster 5-6 Shuttle SRBs together as the first stage. You would get a first stage with the thrust of a Saturn V.
 
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elguapoguano

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I'm just happy the option is being looked at. I mean the more mass we can get into space the better. If we are really going to go back to the moon then on to mars, it's going to require a whole lotta mass on orbit. <div class="Discussion_UserSignature"> <font color="#ff0000"><u><em>Don't let your sig line incite a gay thread ;>)</em></u></font> </div>
 
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propforce

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That's what the maker of SRB (Allian Tech) would love to have you think.... solve every problems with SRBs !! <img src="/images/icons/laugh.gif" />. <br /><br />Clustering works upto an extent. After that, the control, aerodynamics drag, etc., become issues. If you want SRB, it might be better off just to have them make bigger diameter SRBs.<br /><br />The Shuttle's SRB is not a good choice for expendable launch vehicles. It has a "reusable" requirement that totally does not make sense at all. In today's world, making the SRB out of composite casing makes more sense. It's much lighter and less expensive. Both Atlas and Delta IV uses the graphite epoxy motor (GEM) casings for their SRBs. <div class="Discussion_UserSignature"> </div>
 
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propforce

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Ironically this is the exact problem NASA was trying to solve previously with the space launch initiative (SLI) program, before it was mercilessly killed to make room for the new space exploration initiative (SEI) by the Bush adminstration (I know... someone is going to comment <i>which Bush adminstration</i>!!).<br /><br />In the SLI, they looked at all kind of designs for heavy lift, including the booster will fly back by itself (aka - liquid flyback booster, LFBB) and SRB, etc. <div class="Discussion_UserSignature"> </div>
 
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eldensmith

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propforce writes:<br /><br /><i>The Shuttle's SRB is not a good choice for expendable launch vehicles. It has a "reusable" requirement that totally does not make sense at all. In today's world, making the SRB out of composite casing makes more sense. It's much lighter and less expensive. Both Atlas and Delta IV uses the graphite epoxy motor (GEM) casings for their SRBs. </i><br /><br />The current RSRM (4 segment) structure weights 192,000 pounds with an 85/15 ratio of fuel to dry mass. If ATK Thiokol went 100% expendable, and used composites and plastics and changed that ratio to 90/10 that would add at least 64,000 pounds to the 2nd stage with a significant fraction of that added to net LEO payload.<br /><br />A 5 segment plastic RSRM plus RL-10 cluster might well lift over 50,000 pounds to LEO for about $50 million per shot. $1000 per pound. $40M for the RSRM and $10M for 3 RL-10s with a 2nd stage LH2/LOX tanks worked in there somewhere.<br /><br />Now, separate crew and cargo and fly astronauts on a smallish Falcon V for rendevouz in LEO. Send CEV up crew-less and send astronauuts up later in Falcon V or even Soyuz.<br /><br />Three astronauts; a descent module; AND a 50,000 pound spaceship in LEO for an all up cost of $100 million. Laucnh 2 of these Thiokol thingees and have a 100,000 pound re-useable CEV that never returns to Earth, using Falcon V or Soyuz or Kliper for crew transfer. <br /><br />A single Delta IVH will cost much more. <br />
 
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najab

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><i>In reality, if this concept is to be taken seriously, engineers will look into beef up the core structures to handle the increased thrust and acceleration.</i><p>That goes without saying, and I was only being 80% serious with the description. However, the Shuttle SRBs at ignition provide over 3 million pounds of thrust, a fully loaded Delta-4 is a bit over 500,000 pounds. 7 million pounds of thrust lifting 500,000 pounds of mass <b>would</b> be fun to watch (from a safe distance). <img src="/images/icons/laugh.gif" /><p>><i>For example, one can delay ingniting the core engine(s) until right before the SRB burn-out, thus making the core a 1.5 stage. This may significantly boost (pun-intended ) payload performance.</i><p>Hey, it worked (most of the time) for Titan, don't see why it shouldn't work for Delta/Atlas!</p></p></p>
 
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propforce

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You're right. If you strap the RSRM class booster with over 3 million pounds thrust, you're looking a whole new class of vehicle !! <img src="/images/icons/laugh.gif" /><br /><br />For heavy lift with a payload of 100 MT (220,000 lbm), one can use the Russian RD-170, two for liquid strap-on plus one at the core as boosters, can get you over 4.8 million pound thrust at lift-off. That and a powerful 2nd stage engine in the the SSME class will get you the heavy-lift capability. <img src="/images/icons/cool.gif" /> <br /><br />If replace the RD-170 with RSRM or ASRM class SRBs, one will need to increase the propellant tank for either the core (making it a 1.5 stage), or the 2nd stage, to make-up the lower Isp. <div class="Discussion_UserSignature"> </div>
 
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propforce

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Elden,<br /><br />3 RL10s for $10 million? Where can you buy them that cheap??? <img src="/images/icons/smile.gif" /><br /><br />What is the Isp you're assuming for the plastic RSRM? Same as the existing? <div class="Discussion_UserSignature"> </div>
 
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eldensmith

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<i>3 RL10s for $10 million? Where can you buy them that cheap???</i> <br /><br />$2.5M to $3M each is the number I have heard bandied about for a basic RL-10. Robert Zubrin threw out $3M at the SpaceVision conference. <br /><br />google came up dry.<br /> <br /><i>What is the Isp you're assuming for the plastic RSRM? Same as the existing? </i><br /><br />Why not? Keep the fuel formula and fuel design identical to existing, skip re-useability and substitute composites to the maximum extent possible.<br />
 
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propforce

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Elden,<br /><br />What I meant was, why not use the old ASRM Isp instead of the Shuttle RSRM? The ASRM gets a vacuum Isp of 286 sec, compared to 267 sec on the RSRM. The design came with a 12% dry mass fraction, better than the existing 15% on RSRM.<br /><br />ATK was in the phase I competition of the EELV contract, but they were not selected for the phase II. I'd suspect they proposed the architecture you've just described. <br /><br />What amount of mass do you have in mind for your proposed 2nd stage ? Mass fraction? <div class="Discussion_UserSignature"> </div>
 
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eldensmith

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Why RSRM rather than the terminated ASRM booster? Doesn't that open old historical wounds about Florida and Utah and President Reagan? <img src="/images/icons/wink.gif" /><br /><br />Rather than get into that I merely extrapolate from what is available, today.<br /> <br />Retain the existing RSRM configurations as much as possible to reduce development costs, simply swap in composites keeping as much of the proven characteristics as possible. After the Challenger upgrades, performance has been flawless.<br /><br />And RL-10s? How basic can you get? I am woried about $$ per pound to LEO not engineering elegance or maximizing overall efficiency.<br />
 
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john_316

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<br />So why not use the Shuttle SRB's with a "new" or improved Core Booster that can lift 50k lbs to LEO and or GEO/GTO?<br /><br />I imagine that it can be man-rated without any problems. I sincerely think there can be simplicity here.<br /><br />I know they probably did the studies already for this concept. So why does it have to cost more than the shuttle?<br /><br />So they can use the EELV's for cargo and use the new HLV for CEV and other aplications that the EELV can't perform.<br /><br />Just a simple gesture at expanding the human presence into the solar system... <br /><br />
 
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halman

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propforce,<br /><br />How do the state-of-the-art solid rocket motors compare to state-of-the-art liquid fueled motors in terms of ISP, dry mass fraction, and other measuring sticks? Isn't it possible to scale up a liquid fueled booster a lot easier than a solid fueled? How close do kersene and lox motors come to hydrogen and lox? Would a first stage using solids and a second stage using liquids work? How about vice-versa? <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>
 
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eldensmith

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<i>propforce, <br /><br />How do the state-of-the-art solid rocket motors compare to state-of-the-art liquid fueled motors in terms of ISP, dry mass fraction, and other measuring sticks? Isn't it possible to scale up a liquid fueled booster a lot easier than a solid fueled? How close do kersene and lox motors come to hydrogen and lox? Would a first stage using solids and a second stage using liquids work? How about vice-versa? </i><br /><br />Not addressed to me, but I will give my answer.<br /><br />The ability to "scale up" is irrelevant until we have a robust presence out there. Thiokol SRBs are in production, have a 99.5% + success rate, and are subject to commodity pricing, meaning we know EXACTLY how much a 5 segment SRB will cost.<br /><br />Using composites rather than aluminum for dry mass will be an incremental improvement rather than a clean sheet fresh start because the solid fuel shapes can remain essentially unchanged.<br /><br />A 5 segment Thiokol SRB plus a 3 RL-10 upper stage should cost $50 million (give or take) and lift 50,000 pounds (give or take) for about $1000 per pound. With minimal upfront design costs. <br /><br />Besides, two 5 segment SRBs with a big tank and a cluster of RS-68s and we are scaled about as big as we can possibly use for the foreseeable future.<br /><br />= = =<br /><br />No need to man-rate the SRB + RL-10 idea. Just buy Klipers. ;-) <br /><br />= = =<br /><br />As a non-technical observer, it seems to me that the Russians and Ukrainians have us licked on efficient low cost medium lift. Compare the cost to per pound to LEO for Delta and Atlas with Proton and Zenit (not be mention Soyuz-2) and how can we compete except for government funded projects?<br /><br />But going big, really big? Ironically, the US can build much bigger rockets than those guys, if we choose to. A big shuttle derived will dwarf even Energia.<br /><br />Why continue a race - - US EELV versus Zenit/Proton - - when we are clearly so far behind?
 
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john_316

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Ok now hers my questions for Heavy Lift concerning CEV...<br /><br /><br />I am using Delta as a reference not to exclude Atlas-5...<br /><br />The Delta-4 Heavy can lift 13,130 kg (28,950 lb) to GTO.<br /><br />But a 5-6 man crew CEV is going to weight what? Any ideas?<br /><br />The Apollo CM and CSM weight in at 30,329 kg (66,864 lb) combined.<br /><br /><br />Okay so will our new CEV also have a Crew Service Module? Or will the Crew Module and Sevice Modules be combined into one unit?<br /><br />Because If I look correctly at this the Apollo was also 3.9 m in the fairing size and the D4Hvy can take a 5m fairing. <br /><br />But niether the Atlas or Delta can take 66,000 lbs to GTO and most of all, most of us are talking about 50,000 lb to GTO in a modified configuration.<br /><br /><br />I am sorry even with our current technology I can't see building a 5-6 man CEV under 25,000 lb and most of all to have characteristics of the original Apollo CSM for under 60,000 lbs. Not for 5-6 man crews. Especially if they are to be translunar vehicles as well. They all would have to be different vehicles or a new CSM would have to be built for such a journey and just a CM to be built for station and LEO operations.<br /><br />So in my opinion we have to have a heavy lift vehicle much like Saturn. So in this reference I think Shuttle-C/Z and possibly Magnum lifters are the necessity and conclusions for near term heavy lift for moon/maria missions. <br /><br />Where is there an alternative? <br /><br />A CEV for under 30,000 lb that can do the same work as the original Apollo CSM/CM and with a crew of 5-6? Not likely.....<br /><br />
 
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najab

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One idea that has been bandied around is to put the CEV on top of a five-segment SRB. The second stage would be a SSME-derived expendable engine.<p>The numbers that were floating around said it should be able to deliver a ~60,000lb payload to LEO.</p>
 
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mrmorris

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<font color="yellow">"The Apollo CM and CSM weight in at 30,329 kg (66,864 lb) combined. <br />...<br />I am sorry even with our current technology I can't see building a 5-6 man CEV under 25,000 lb and most of all to have characteristics of the original Apollo CSM for under 60,000 lbs. Not for 5-6 man crews."</font><br /><br />I've spent a <b>great</b> deal of time researching the original Gemini spacecraft in the past several weeks and working out what the possibilities would be for a modern craft built along the same lines. The weight reductions from modern electronics, power systems, etc. are huge. I have not spent the time to take a similar look at a modern Apollo CM (nor do I intend to), but based on what I learned from Gemini -- I firmly believe that your 60,000 pound figure is high. 25,000 pounds might be stretching probability for a 5-6 person crew with a craft of those capabilities, but I certainly wouldn't rule it out without doing some actual research.
 
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mattblack

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Gemini had no pressurised docking capability, so anything based on that fact alone would be useless. Scaling it up and changing the forward nose to a hatch/docking probe assembly would so alter it, it would be a totally different ship. You'd might as well keep the Apollo shape and configuration. I also did some checking and found that the Apollo CSM as used on the second Skylab flight was 30,506 pounds. <br /><br />The reason it was so much lighter than the Apollo 17 CSM (nearly 67,000 pounds) was because for earth orbital flights they deleted two of the CSM's four propellant tank loads, because it didn't need all that prop as it wasn't decelerating into lunar orbit, then burning out of it again.<br /><br />On that criteria alone, a new CEV could easily be launched on a Delta 4 or Atlas 5. A fully fuelled CEV for lunar and beyond would have to be launched on a Shuttle-derived booster or a 5-corestage Atlas or Delta.<br /><br />That's why I'm a fan of the Boeing concept for CEV.<br /><br /> http://www.projectconstellation.us/articles/concept-gallery/sec_stage_album.php?albid=NA==<br /><br />Besides, with Lockheed-Martin winning the Joint Strike Fighter contract, I'm really rooting for the Boeing/Northrop Grumman alliance!!<br /> <div class="Discussion_UserSignature"> <p> </p><p>One Percent of Federal Funding For Space: America <strong><em><u>CAN</u></em></strong> Afford it!!  LEO is a <strong><em>Prison</em></strong> -- It's time for a <em><strong>JAILBREAK</strong></em>!!</p> </div>
 
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najab

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><i>Gemini had no pressurised docking capability, so anything based on that fact alone would be useless.</i><p>Have you taken a look at the "Gemini: We can rebuild it..." thread in the SS&T forum? On paper, at least, it's not useless.</p>
 
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