new launch vehicle

[tap_sa]

<font color="yellow">"Am I right in getting about $12 per pound?"</font><br /><br />pound of propellant costs 5c/lb * 0.75 + 25c/lb * 0.25 = 10c/lb. LOX/RP-1 vehicle with 1% payload fraction has about 95% of it's lift-off weight as propellant. So one pound costs 95lb * 10c/lb = $9.5 in propellant.<br /><br />As you can see it's dirt cheap so designing exotic scramjet and huge terrestial ramps to save it a little doesn't make much sense.<br /><br />I'd add to skywalker01's list<br /><br />13) airlaunch.<br /><br />High-altitude launch simplifies engines nicely.

 

[larper]

Look at my "Fast vs Slow" list. Normally, I would say that airlaunch is just another "Fast" system. You have the added complexity of the airborne platform.<br /><br />However, I see one possible exception to this: Rutan. His airlaunch system is "Slow". But, then his spacecraft becomes a "Fast" system.<br /><br />Anyway, I would still classify an airlaunch-to-orbit system as fast, since the orbiter itself still goes fast in the atmosphere, and any re-entry system would return fast as well.<br /><br />So, today we are stuck with "fast" systems. So, make them safe, reliable, and simple. Bulletproof. Like you said, don't add complexity to save $10 in fuel. <div class="Discussion_UserSignature"> <p><strong><font color="#ff0000">Vote </font><font color="#3366ff">Libertarian</font></strong></p> </div>

 

[no_way]

<blockquote><font class="small">In reply to:</font><hr /><p>You have to get over the assumption that reusability implies cost savings<p><hr /></p></p></blockquote><br />Im well over it, but it is significantly more probable to achieve high flight rates in near future with reuseable vehicle, than someone building a high production rate expendable vehicle manufacturing line.<br /><br />and without high flight rate you cant have high reliability nor low cost, no how.<br />I guess i dont need to remind you that you cant have 99.9% reliable vehicle without thousand launches.<br /><br />There's also the fact that with expendables, you are throwing away engines and tankage which ups the basic material cost considerably. For pure reuseable, its theorethically possible to approach fuel costs ( i.e. the before calculated $10 a pound to orbit ) but for expendables you have to factor in continuous production line running costs, material costs etc.

 

[larper]

I agree with most of what you said. But I think we have to start looking at things another way.<br /><br />You said the key to low cost is high flight rates. That is probably a real good assumption. You then say that reusability means high flight rates, because you don't see a high rate production line. This is where I SLIGHTLY disagree. <br /><br />Would you classify automobiles as expendable? Probably not. But, there are hundreds of auto building plants that are in constant production. This is because the automobile is not INFINITELY reusable.<br /><br />So, I say, make a vehicle that is expendable. By expendable, I mean you are willing to throw it away, not that you actually throw it away. Get the production assembly line up and running. Now, improve the vehicle over time. Make it more reusable. Maybe you can go from 1 flight per vehicle to 2 flights. GREAT! Then, maybe 5. AWESOME. Pretty soon, you have a very reusable vehicle that is based on reliable technology. And, you have a high rate production line that can support multiple launches, multiple customers, etc. And what type of system MIGHT be the best design to achieve such a path? Why, DC-X!!!!<br /><br />The first DC-X's might be completely non-reused. But, as the engineers look over the systems after their flights, they might start to see where they can make some slight improvements to achieve reusability. This might have happened with Apollo if that program had continued. The capsules were in pretty good shape, possible reuseable after referbishment. There were plans to make some of the stages reusable as well. Given time, the Apollo system might have become reusable and cheap at the same time. <div class="Discussion_UserSignature"> <p><strong><font color="#ff0000">Vote </font><font color="#3366ff">Libertarian</font></strong></p> </div>

 

[skywalker01]

I think you are looking at this a little too black and white and in the process throwing out all the shades of gray.<br />I think we can do better than all chemical rockets with a payload fraction of 1 to 2 percent and do it for much less than we pay today.<br />

 

[skywalker01]

1) ground accelerator launched rockets, <br />2) ground accelerator launched ramjet/rockets, <br />3) ground accelerator launched ramjet/scramjet/rockets, <br />4) RBCC, <br />5) ground accelerator launched RBCC, <br />6) ducted rocket, <br />7) ground accelerator launched ducted rocket, <br />8) TRCC, <br />9) subsonic or supersonic air launched rocket,<br />10) subsonic or supersonic air launched ramjet/rocket,<br />11) subsonic or supersonic air launched ramjet/scramjet/rocket,<br />12) 1 thru 11 in combination with an Earth Orbiting Elevator, <br />13) 1 thru 11 as reusable first stage LVs with expendable upper stages, <br />14) laser launch, <br />15) big dumb booster, <br /><br />any more?

 

[skywalker01]

Regarding flight rates:<br /><br />How about we limit ourselves to the current launch market or the launch market for the next 10 to 15 years in order to keep this as real world as possible?

 

[propforce]

<blockquote><font class="small">In reply to:</font><hr /><p>There's also the fact that with expendables, you are throwing away engines and tankage which ups the basic material cost considerably. For pure reuseable, its theorethically possible to approach fuel costs ( i.e. the before calculated $10 a pound to orbit ) but for expendables you have to factor in continuous production line running costs, material costs etc. <p><hr /></p></p></blockquote><br /><br />HA !!! <img src="/images/icons/laugh.gif" /> Is that why the Shuttle is still continuing to cost way more than the EELVs, giving a comparable payload capability? <br /><br />SDLV will not cost less than existing EELV neither. Griffin's decision is a "job" decision, not based on cost, technical or launch reliability. <div class="Discussion_UserSignature"> </div>

 

[larper]

<blockquote><font class="small">In reply to:</font><hr /><p>How about we limit ourselves to the current launch market<p><hr /></p></p></blockquote><br />You mean like Burt Rutan did? <div class="Discussion_UserSignature"> <p><strong><font color="#ff0000">Vote </font><font color="#3366ff">Libertarian</font></strong></p> </div>

 

[propforce]

<blockquote><font class="small">In reply to:</font><hr /><p><br />1) ground accelerator launched rockets, <br />2) ground accelerator launched ramjet/rockets, <br />3) ground accelerator launched ramjet/scramjet/rockets, <br />4) RBCC, <br />5) ground accelerator launched RBCC, <br />6) ducted rocket, <br />7) ground accelerator launched ducted rocket, <br />8) TRCC, <br />9) subsonic or supersonic air launched rocket, <br />10) subsonic or supersonic air launched ramjet/rocket, <br />11) subsonic or supersonic air launched ramjet/scramjet/rocket, <br />12) 1 thru 11 in combination with an Earth Orbiting Elevator, <br />13) 1 thru 11 as reusable first stage LVs with expendable upper stages, <br />14) laser launch, <br />15) big dumb booster, <br /><br />any more? <p><hr /></p></p></blockquote><br /><br />If you think expendable rockets are expensive, just try to spend the money to develop one of those above !! <img src="/images/icons/laugh.gif" /> <div class="Discussion_UserSignature"> </div>

 

[larper]

The reason I like SDLV for payload launches is because there is no EELV existing or on the books that can come close to SDLV for mass or volume to orbit.<br /><br />The more mass/volume you can put up in one shot, the more integration you can do here on the ground, and that instantly lowers cost. <div class="Discussion_UserSignature"> <p><strong><font color="#ff0000">Vote </font><font color="#3366ff">Libertarian</font></strong></p> </div>

 

[skywalker01]

Just thought of another one<br /><br />1) ground accelerator launched rockets, <br />2) ground accelerator launched ramjet/rockets, <br />3) ground accelerator launched ramjet/scramjet/rockets, <br />4) RBCC, <br />5) ground accelerator launched RBCC, <br />6) ducted rocket, <br />7) ground accelerator launched ducted rocket, <br />8) TRCC, <br />9) subsonic or supersonic air launched rocket, <br />10) subsonic or supersonic air launched ramjet/rocket, <br />11) subsonic or supersonic air launched ramjet/scramjet/rocket, <br />12) high altitude balloon launched rocket,<br />13) high altitude balloon accelerator launched rocket,<br />14) 1 thru 13 in combination with an Earth Orbiting Elevator, <br />15) 1 thru 13 as reusable first stage LVs with expendable upper stages, <br />16) laser launch, <br />17) big dumb booster, <br /><br /><br />any more? <br /><br />

 

[skywalker01]

Rutan isn't going to orbit.

 

[tap_sa]

t/Space is and many people think t/Space = Rutan <img src="/images/icons/wink.gif" />

 

[skywalker01]

<< If you think expendable rockets are expensive, just try to spend the money to develop one of those above !!>><br /><br />a) Take the wing off a Pegasus and launch it from a high altitude balloon at 100,000 ft.<br />The payload will go up and you trade the cost of the balloon for the cost of flying the carrier aircraft.<br /><br />b) there was a study a few years back that suggested air launching the upper three stages of a pegasus from the back of an SR-71. Payload was 900 lbs to orbit. It eliminated the cost of the pegasus first stage and had a SR-71 cost to Mach 3 of $200,000.<br /><br />Those are two examples that come to mind. I am sure there are more.<br /><br />I wonder what adding a duct would do to the performance and cost of an SRB and how that would influence the design of an SRB launched CEV?

 

[skywalker01]

<<t/Space is and many people think t/Space = Rutan >><br /><br />When do you expect them to start flying at what size payloads and how many flights per year over the next 15 years and add that to the current market model.<br /><br />By the way, the last time I looked at space launch market data the global total was running around 1.8 million lbs/yr to LEO. Has that changed?

 

[propforce]

<blockquote><font class="small">In reply to:</font><hr /><p>a) Take the wing off a Pegasus and launch it from a high altitude balloon at 100,000 ft. <br />The payload will go up and you trade the cost of the balloon for the cost of flying the carrier aircraft. <p><hr /></p></p></blockquote><br /><br />You don't gain that much with just altitude alone, a common misconception folks make, you need the kinetic energy, e.g., velocity, to match the orbital velocity (Mach 25) in order to go to and STAY in orbit. Otherwise, you'll drop back down as a rock just like the Spaceship One.<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p>b) there was a study a few years back that suggested air launching the upper three stages of a pegasus from the back of an SR-71. Payload was 900 lbs to orbit. It eliminated the cost of the pegasus first stage and had a SR-71 cost to Mach 3 of $200,000. <br /><p><hr /></p></p></blockquote><br /><br />1) SR-71 is very expensive to operate, more so than a L1011 + the cost of Pegasus 1st stage.<br /><br />2) Airlaunch in general is more expensive than a ground launch. You're going the wrong direction for cheaper access to space.<br /><br />3) 900 fricking lbm??? !!! ??? Whaddahell can ya do with a measley 900 lbm in orbit other than contribute to the space junk problem ??? <br /><br />Okay I am just kidding on this one. You can probably send 2 volunteer passengers for space tourism and charge them $10M each <img src="/images/icons/wink.gif" /><br /><br />Charge them another $10M each if they wish to come back to earth.<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p>I wonder what adding a duct would do to the performance and cost of an SRB and how that would influence the design of an SRB launched CEV? <p><hr /></p></p></blockquote><br /><br />Are you adding a duct in front or at the back of SRB? It maybe kinda pretty looking, seeing flame coming out at the <b>inlet</b> of duct. Hmmm... forward thrust - reverse thrust = zero net thrust. A standing rocket? <div class="Discussion_UserSignature"> </div>

 

[tap_sa]

If current market model doesn't change there's no room for any newbies. If newbies display 1/2 - 1/3 launch prices, that might change the picture. I'd expect some of the new players to create new markets, such as space hotel, fuel-depot, <i>dry dock</i> (LEO 0g shirt-sleeve environment to build/repair sats/spacecrafts) etc.

 

[skywalker01]

<< You don't gain that much with just altitude alone, a common misconception folks make, you need the kinetic energy, e.g., velocity, to match the orbital velocity (Mach 25) in order to go to and STAY in orbit. Otherwise, you'll drop back down as a rock just like the Spaceship One. >><br /><br />The savings in delta-vee due to drag loss from not having to climb from 35,000 ft to 100,000 ft are at least 1500 ft/sec as well as the weight savings of not carrying the wing (approx. 700 lbs if memory serves), and the cost of the wing. Plus the average Isp is higher due to being out of the atmosphere.<br />Add them all up and it does make a difference.<br /><br /><<SR-71 is very expensive to operate, more so than a L1011 + the cost of Pegasus 1st stage. />><br /><br />According to the report (from NASA MSFC) the cost of using the SR-71 to carry the upper three stages of the pegasus with payload to Mach 3 was $200,000.<br />That is significantly less than the cost of the 1st stage and use of the L-1011 carrier aircraft.<br /><br />As to what purpose it would serve? How about resupply flights to the ISS as a backup to Progress and Shuttle?<br />In any case, it was only an example to disprove your eariler statement that seemed to imply that there was no point in trying anything on the list as it would cost too much to develop.<br /><br />I guess my biggest complaint with your posts is the closed minded attitude. An attitude that appears to have taken over the aerospace business as a whole and has a lot to do with the lack of progress that has been made over the last 20 plus years.<br /><br /><< Are you adding a duct in front or at the back of SRB? It maybe kinda pretty looking, seeing flame coming out at the inlet of duct. Hmmm... forward thrust - reverse thrust = zero net thrust. A standing rocket? />><br /><br />Cute.<br />Goes with the pattern of thought that there is no point of looking for improvement. Obviously with an attitude like that you never wi

 

[spacefire]

with available technology, the only cost effective option to deliver any kind of payload to LEO is an RBCC scramjet. <div class="Discussion_UserSignature"> <p>http://asteroid-invasion.blogspot.com</p><p>http://www.solvengineer.com/asteroid-invasion.html </p><p> </p> </div>

 

[skywalker01]

<< If current market model doesn't change there's no room for any newbies.>><br /><br />I disagree. If you wait for an increase in market size before designing a better lower cost launch system then you will be waiting a long time.<br /><br />How about designing a better lower cost launch system based on the current market size and letting the lower cost expand the market.<br />The history of aircraft transportation is full of aircraft that were too large for the markets of their time and failed as a result. The successful ones were sized for the existing market and did it for less than their competitors. When the market grew as a result of their decreased operating costs they increased the flight rate until someone came up with an even newer and more cost effective aircraft sized for this new market.<br />I have no doubt that this pattern will hold true for the launch business.

 

[skywalker01]

I saw a paper a few years back that compared a ground accelerator launched RBCC to an RBCC that took off on its own. It looked at them both as SSTOs and with expendable upper stages. Of the 4 options the ground launched RBCC with expendable upper stage had the lowest cost to develop and operate (it was the smallest vehicle and the ground accelerator was only to get the ramjet up to speed so that the rocket wasn't needed for the take-off roll).<br /><br />So yes I agree with you that RBCC looks very very promising but I don't think it is the only possible solution.<br /><br />By the way this web site shows a form of combined cycle propulsion both with an expendable upper stage and flying to the bottom of an Earth Orbiting Elevator that you might find interesting.<br />http://www.affordablespaceflight.com<br /><br />It could be that a ground accelerator launched RBCC with expendable upper stage designed with the future ability of docking with an EOE might be the best answer.<br /><br />Which reminds me, I remember there being two basic flight profiles that were considered for these types of vehicles. One was a high Q profile that had serious thermal problems, and the other was a low Q profile that avoided the thermal probelms but had a larger ramjet. If memory serves, the low Q profile looked to be the most doable based on current technology.<br /><br />If you have any links on RBCC LVs I would like to see them.

 

[skywalker01]

<< He was just responding to the post which made no sense. >><br /><br />What didn't make sense?<br />

 

[larper]

Putting a scoop onto an SRB, I believe. <div class="Discussion_UserSignature"> <p><strong><font color="#ff0000">Vote </font><font color="#3366ff">Libertarian</font></strong></p> </div>

 

[skywalker01]

Thank you both for responding.<br /><br /><< I wonder what adding a duct would do to the performance and cost of an SRB and how that would influence the design of an SRB launched CEV? />><br /><br />When I read that it clearly implies a ducted rocket, aka, ejector rocket.<br /><br />But I gather from both of your posts that it was not clear to you. <br /><br />For myself, it appeared that he had understood my post and that he was being patronizing and condesending in addition to close minded.<br /><br />But I also suspect that you gentlemen know each other from long association here and are a better judge of his communication style and intent than I am. If that is the case then I will defer to your judgement and I apologize to all of you for my poor communication, and to propforce for my misunderstanding of his intent, and my waspish words.<br /><br />Again, thank you both for responding.<br />