TSTO

[scottb50]

I don't even have a basement so obviously I have no ramjets.<br /><br /><br /> <div class="Discussion_UserSignature"> </div>

 

[rocketman5000]

or rather than start two seperate efforts work together to produce a more unitified effort. There is plenty of work to go around for everyone.

 

[frodo1008]

Your start small ideas may very well be the only way to get a pure private effort of the ground. Although I do also hope that Virgin Galactic'e and Burt Rutan's efforts (as well as spacex) are also successful! And I wish you all the success in the world with it! Even though I support NASA's current designs myself, I really don't give a hoot how mankind eventually gets into space in a big way, I just want to see it done! So good luck and God's speed to you!<br /><br />It would really have been nice to have seen the shuttle built to some of the original designs! It was only klugged together the way it was because of funding limitatations imposed on NASA by a government bent on blasting holes in rice paddies in Southeast Asia! What worries me now is that we seem to be doing the same thing all over again, only this time in deserts in the Middle East. Will we NEVER learn!<br /><br />Most of the original designs involved a booster that then had the orbiter directly placed on its back, and rolled to the launch pad on its own landing gear. It was then placed into a vertical position (the Russians are very good at this relatively cheap and affective technique) and blasted off. The engines would have been all liquid engines (no Challeger accident) and the booster would have been a totally reueable fly back type of booster. Even the orbiters were to be large enough to not need an external tank! The initial payloads would have been less than the current shuttle, which was dictated by the militaries needs NOT those of NASA), but remember that even 10 people only weigh between 3,000 and 6,000 lbs, even with all their survival gear!. The initial development costs of such systems were thought to be too expensive for the time. Although, I really don't see where the over all cost of the current system as it now exists has been that much of a bargain!<br /><br />I believe that such a system could indeed be built and flown for a lot less than the current shuttle, but it would tak

 

[tap_sa]

<font color="yellow">"launching nano sats. To start with, you can charge the most per kg in orbit of any size range (right now prices range from $20k-50k/kg)"</font><br /><br />Pegasus seems to be king of the hill; ST5 mission put total of 75kg payload into orbit and AFAIK Orbital charges at least $10M per launch, meaning six digit $/kg figures <img src="/images/icons/blush.gif" />

 

[mlorrey]

Pegasus charges the same no matter what the payload size is, which is pretty typical. This is why comsat mass is growing: to take advantage of the full payload capacity of the larger launch vehicle capacities. If your payload meets their launcher max capacity it gets down to about $6k-8k/kg depending on the model. This is where putting together a full manifest saves money, but you need to factor the mass of a manifest dispenser as well (such as CubeSat's P-Pods that are used to deploy their sats) and the cost of assembling a more complex payload than just one satellite.<br /><br />If you can orbit 50 kg and want to maximize revinue, you could launch 40 CubeSats and charge $1.6 million at the going rate, or cut the price to take business away from CubeSat.org. Getting 40 teams to go with you would likely require a lower price point than what they are charging.

 

[scottb50]

I would rather see manned platforms. Not to disparage nano-satellites that could be placed in orbits as needed. The idea should be putting manned assets in Space and building on them. <br /><br />Use platforms for communications, mapping, real time Google Earth as an example. Once established in LEO it is then a fairly simple matter to leave LEO.<br /><br />You can't do that with Pegasus or Falcon 1 through 9. What you need is a rocket that can take hundreds of nano-satellites, people and other payloads into LEO every month or so. Bigger is better, Tim was right! <div class="Discussion_UserSignature"> </div>

 

[mlorrey]

Bigger is also costlier. If you don't have a trust fund sitting around going to waste, or the capacity to both develop a workable design and a workable business plan AND be able to sell both to a lot of venture capitalists, all talk of such a launcher is just useless jabber. Such investors are also going to want to know what your track record is, experience, things you've done to merit their trust in your ability to do what you say you are going to do. For a start-up, a lot of that needs to be built up by starting small, developing a record with small launchers: suborbitals, then orbitals. Once you have such a record, then people will trust that when you say you are going to do a man rated launcher that you both can and will do it, AND that people believe you enough to trust their lives and fortunes on your launcher.

 

[frodo1008]

Correct! For instance. let us hope that spacex can at least pull out of its current nose dive problems before it crashes totally!<br /><br />On the other hand it seems as if Burt Rutan and Virgin Galactic are at least realistically exhibiting the proper amount of humility and caution. <br /><br />Hope your own efforts are going successfully! Are you only going to tell us through your excellent site, or can you help us out here?

 

[scottb50]

I don't think even Musk has enough money to build up to a useful vehicle, the nine engine version is pretty complicated and doesn't carry that much. It seems like you want to do plan A to get to plan B which is what you wanted to do in the first place. So you spend twice as much but you keep the stockholders happy, which is the point anyway. <br /> <div class="Discussion_UserSignature"> </div>

 

[no_way]

you pretty much proposed what was descibed in "The Rocket Company" <br /><br />http://www.hobbyspace.com/AAdmin/archive/SpecialTopics/RocketCom/titlePage.html <br /><br />did you read it when it was published on HobbySpace ? Chapters 1 and 4 are still available online <br /><br />a couple things differ, they wanted upper stage to be reuseable too which does not have to be the requirement from day one.<br /><br />and our fictional heroes .. er. .. enterpreneurs actually got around the requirement of finding a killer app for launches, they simply sold the vehicles. <br /><br />I bet that once you prove it works reliably enough with sufficiently low operating costs, barring ITAR, you could find dozens of customers in different countries for system like that.

 

[j05h]

Scott- your TSTO reads a lot like Kistler's K1, uprated. A simple, robust first stage with a reusable upper stage. They would have made their millions launching broadband constellations. <br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[scottb50]

I haven't read the serial, but have seen it at that site. <br /><br />I doubt the "build it and they will come" scenario would work anyway. If you provide the capability of the Shuttle commercially there needs to be a market. As for exporting vehicles I would think the infastructure needed to launch it as well as U.S. export requirements would pretty much require payloads being delivered for launch to a single or possibly a couple of sites. Vandenberg facilities still exist and could be refurbished.<br /><br />As for a killer AP I've been thinking about instant anywhere anytime communication capability. A number of large LEO platforms that transfer communications from a central facility to individual hand-held or larger devices. An I-POD size unit that lets you remotely operate a super computer from anywhere. <div class="Discussion_UserSignature"> </div>

 

[mlorrey]

Right now I'm converting my ramjet design to paper stencils to use to cut sheetmetal. I've got my welder and other equipment set up, and sheetmetal on site. I'm shopping for a small linear actuator to control the spike, and small fuel pumps. The design is a 4" dia ramjet, with adjustable spike, which would develop about 240 lbs thrust at peak speed, though I'd need wind tunnel access to reach that speed. My tests on site are limited to using a leaf blower to generate airspeed on the test rig.

 

[mlorrey]

Musk's eBay stock is worth about $200 million. I'm told he's invested about $100 million in SpaceX, only a small part of which has gone into Falcon1 production. Most is into engine development and manufacturing infrastructure. They've bought a lot of top quality tooling and production machines, state-of-the-art friction stir welding, etc. giving them the capacity to produce rockets on an assembly line rather than as custom one-off jobs.<br />One of their machine suppliers, Sodick, features SpaceX prominently in their marketing materials. I think I posted one of their pics yesterday. Here is another...

 

[skyone]

Mlorrey, will you be posting pics and information at your site? or perhaps a blog?

 

[mlorrey]

Yeah, as they come along. I'm going to be putting up a paper on my research proposal for the X-106 as well as a bit of market analysis.

 

[scottb50]

It resembles Kistler's rocket, somewhat, but on a totally different scale.<br /><br />What I have in mind is four SSME's, two Shuttle class SRB's and two turbofans powering the first stage.<br /><br />The second stage would use two SSME's, with extended nozzles and would stay in Space for use as orbiting Station Modules, Lunar and Martian components and as orbital delivery vehicles. Payloads will vary from Cargo Modules to mission specific payloads to manned launch and return vehicles.<br /><br />Fly the booster stage back, service it horizontally and erect it on a Shuttle Launch Platform for transport to the pad and launch. The second stage and payload would be integrated and attached to the booster once it is in place on the launch platform.<br /><br />During servicing engine changes and structural inspections would be routine and pre-poured SRB segments would be loaded into the SRB Housings hoorizontally. <div class="Discussion_UserSignature"> </div>

 

[josh_simonson]

If you get a large air compressor tank, you could pump it up and use a solenoid to dump it into your ramjet engine to simulate high-speed air travel. Once it's set up it'd be cheap to do many tests. You can probably get this for less than it'd cost to rent a wind-tunnel, and it'd be cheaper, easier and safer than using J rocket engines to get it up to speed. For longer tests you could get a bigger tank or put several in parallel. I see huge old compressor tanks on craigslist sometimes.

 

[scottb50]

I don't see any use for a ram-jet in a launcher. You must be responding to Mlorrey who seems obsessed with them. <div class="Discussion_UserSignature"> </div>

 

[mlorrey]

Firstly, there is a lot of use for ramjets in a launcher. They have the same T/W as LH2/LOX rocket engines, while at the same time have more than four times the Isp as that fuel combination when burning kerosene. Burning LH2, they have 8-10 times the Isp. <br /><br />Moreover, they can operate up to mach 7 or more with MIPCC. Most first stages are exhausted by that time. For instance, the STS SRBs separate at a mere Mach 3.93 at about 150,000 feet. This is well within the speed range of a conservative ramjet design, ramjet missiles have flown above 3.93 since the 50's.<br /><br />Another advantage of ramjets is cost: they are really just tubes with fuel injectors. They cost far less than any other propulsion system out there by any way you look at it. Their simplicity means they can be manufactured at very low cost on production lines with automated sheetmetal cutting and welding machinery.<br /><br />Why they have not been used in any major launch systems speaks only to a space agency and contractor psychology of maximizing the size of one's budget and the amount of work needed to justify hiring lots of engineers and union workers to do.<br /><br />If I am obsessed with ramjets, it is a good obsession and one that other space program proponents should be infected with if they want to bring down the cost of access to space. It will also take such obsession to make ones dreams a reality, so Scottb50's mocking tone belies his lack of seriousness about his own 'project'.

 

[josh_simonson]

Regardless of the merits, I'm always in favor of citizens building window-rattling flamethrowers in their backyards. <img src="/images/icons/wink.gif" /><br /><br />I could also see considerable use for a small, cheap ramjet in sounding rockets, ect. Suborbital tourism could also use ramjets since they don't go near mach 7. I recall SS1 maxed out around mach 3.<br /><br />What velocity would you need to ignite the thing?

 

[scottb50]

Rockets produce a lot of power with a reasonable mass. While Ram-jets have equivenent output the mass to get them to as point they can operate is execessive. <br /><br />the reason they haven't been used is they are dead weight until you are fast enough for them to work. However simple, they are dead weight at launch. LH2-LOX is the only way.<br /><br />Another way to look at it is all, or most, of the first stage water would recycle into the atmosphere. What's used in Space is lost, but the most demanding portion stays.<br /><br />I envision a launcher and a second stage, that can put as much, or more payload into LEO then Shuttle. I would hope others would develop payloads. <div class="Discussion_UserSignature"> </div>

 

[mlorrey]

There is actually a pretty good page with simple instructions for building a simple subsonic ramjet without needing sheet metal or welding equipment. Interestingly enough, this fellow built his ramjet out of two stainless steel coffee travel mugs. A fascinating project.<br /><br />http://cottrillcyclodyne.com/Maggie_Muggs/Maggie.html<br /><br />As I said, this one seems to be purely subsonic, and I'm not sure if anybody has used it to actually propel a model aircraft yet.<br /><br />The ramjet I'm designing should be supersonic capable, and if successful, I will be offering them for sale through my website.<br />

 

[mlorrey]

Ramjets capable of supersonic flight but without any adjustable spike or nozzle geometry (i.e. built for a fixed speed) typically require 200-450 mph to ignite and generate sufficient thrust on their own. Leduc's 010 models were launched at 200 mph from the backs of WWII era bombers.<br /><br />A number of hobbyists have built personal helicopters with ramjets mounted to the rotor tips. They are typically started with either a small electric motor spinning the rotor, though one fellow simple stuffs fuel laden rags in the ramjet pipes, lights them and starts the rotor spinning by hand. Said personal helicopters are known to create a LOT of noise.<br /><br />I plan on tow-launching the man rated versions once those are built. The unmanned suborbital versions with either be launched with the help of D/E/F grade "Estes" style rocket motors, or with peneumatic launch tubes (aka "Potato Guns") for larger versions.<br /><br />Scottb50's proposal of using SRBs, of all things, for his launcher is absurd and inane. Does he realize that one SRB weighs over a million lbs? He is still talking in air castles, offering no plans to raise capital for such a project or demonstrating sufficient resources of his own.

 

[jschaef5]

that is a really cool site mlorry. I never would have thought that you could do that so simply and still have it work right.<br /><br />I almost want to go and build one now just for fun. <div class="Discussion_UserSignature"> </div>