Boeing’s space fuel depot (PM article)

[docm]

Popular Mechanics article....<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p><b>Space Gas Station Would Blast Huge Payloads to the Moon<br /><br /><i>Boeing has unveiled a radical redesign of NASA's plan to return to the lunar surface: save weight (and money) by saving gas for an orbital fill-'er-up, then shoot 15 times more material to the moon. Can the space agency jive with private space to get the new propellant depot off the ground?</i></b><br /><br /> /><br />NASA’s current mission plan (click here for PM’s behind-the-scenes report) calls for the Ares V to send the new lunar lander and its payload into Earth orbit. Once there, Ares V would not only have to dock with the Orion crew vehicle (launched separately on the Ares I rocket) but also restart and provide the initial burn to send the assembled system into a trajectory toward the moon.<br /><br />Boeing’s alternative would combine the Orion rendezvous with a pitstop for gas, allowing the Ares V to lift off from Earth with a much larger payload—and an empty lander. Boeing says this would allow NASA to deliver about three times as much mass to the lunar surface, and over fifteen times as much payload. What’s more, Ares V could then send the lander-Orion package all the way to lunar orbit with full tanks, rather than NASA’s current plan to use extra propellant in slowing down before soft landing. <br /> /><br />Boeing’s plan is to build the depot in pieces like a stripped-down International Space Station, only in modules based on the upper stage of the Delta launch vehicle. Two depots would provide redundancy, each one with a total capacity of 175 tons of liquid oxygen/liquid hydrogen (25 tons for the lander, 125 for the rocket, with margins for boil-off and other contingencies). And while many of the necessary parts and operations (i.e., orbital cryogenic storage and transfer) still</p></blockquote> <div class="Discussion_UserSignature"> </div>

 

[gunsandrockets]

Go depot!

 

[SpaceKiwi]

Bloody nice! The concept is far too perfect to ever see the light of a sunrise on orbit though. <br /><br /> <div class="Discussion_UserSignature"> <p><em><font size="2" color="#ff0000">Who is this superhero?  Henry, the mild-mannered janitor ... could be!</font></em></p><p><em><font size="2">-------------------------------------------------------------------------------------------</font></em></p><p><font size="5">Bring Back The Black!</font></p> </div>

 

[holmec]

Shoot, if your going to refuel, you might as well make a permanent tug to ferry stuff to lunar orbit. That would cut down launch costs or maximize launch efficiency. <br /><br />Now that I think about it, maybe this is a first step toward a reusable TLI tug for Boeing. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[kelvinzero]

I really hope they do this regardless of NASA. How much other business could there be for them?<br /><br />But is it worth the risk that someone will resurrect the orbital atmospheric gatherer thread? <img src="/images/icons/wink.gif" />

 

[jimfromnsf]

No other business than NASA<br /><br />Also notice the orbital atmospheric gatherer thread died? Because it was not viable

 

[kelvinzero]

<blockquote><font class="small">In reply to:</font><hr /><p>No other business than NASA <br /><br />Also notice the orbital atmospheric gatherer thread died? Because it was not viable <p><hr /></p></p></blockquote><br />Thats ridiculous!<br /><br />Most of that thread was you arguing against the weird (and to my mind unrelated) scheme of deacceleting to catch rockets on the way up! <b> And precisely BECAUSE it was unviable!!!</b><br /><br />The moment that topic was split off into another thread, then THAT thread continued on for ages, precisely because it was unviable. I just wanted to hear more about how the vacuum pump was meant to work. Never did.<br /><br />Im prepared to accept your mostly negative opinions on spaceflight because spaceflight is hard and wishful thinking will get us nowhere, and you do apparently know a fair bit. But this is simple history for anyone to inspect:<br /><br />The Orbital gatherer thread <-- mostly arguing against orbital assist idea.<br /><br />Reaching Orbit with an Assit <-- split off from previous thread because off topic.<br /><br />I was very very annoyed to never actually have a discussion about the details of the orbital gatherer, although in the end Paul's reticence was more to blame. I dont actually remember any comments from you against the gatherer concept itself. Maybe it was buried in there somewhere.

 

[gunsandrockets]

Exactly right.

 

[jimfromnsf]

Of course I am

 

[kelvinzero]

Back on topic: I have a good feeling about this, especially given the general interest in in-orbit refueling, eg <br />orbital express

 

[holmec]

Shoot. Boeing will initially try with NASA. I doubt that would be the end of it if they don't succeed the first time around. Refuelling in space is really the next step humans need to take to up exploration. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[thereiwas]

The hard part is that the lifted fuel has to rendezvous with the depot, which might not be anywhere close to the orbit that the other payload goes in. I hope they do not put the depot in such a low orbit like ISS that it keeps decaying all the time, but it does have to be in an inclination that sees a lot of traffic on the way to other places.

 

[baktothemoon]

Who says we can't have multiple depots? If we put up maybe around five smaller depots in several different orbits rather than one big one then we save fuel in trying to reach the "home" depot, so we can have even more payload because we have several convient inclinations to choose from. BTW, could we use the system Bigelow is going to use to assemble his station remotely in order to assemble our space gas station?

 

[jimfromnsf]

"so we can have even more payload because we have several convenient inclinations to choose from."<br /><br />There aren't many. There is only one from the US, 28.5 deg. There isn't one for VAFB since there since sun sycn inclination varies with alt and there are many planes

 

[thereiwas]

Where is the traffic going? You put your gas station on the intersection where the most vehicles go by. I think that is closer to the ecliptic. The truck stops.<br />

 

[j05h]

The propellant depot should go at Earth-Moon L1. <br /><br />It would be able to service GEO satellite-tug stacks coming up from LEO. The delta-v between LEO and EML1 is 0.77km/s. At that location the depot would service tugs for Lunar flights and possibly provide refueling for reusable lunar landers. Cargo tugs would be similar to Parom or the "ACES" proposed upper stage. The facility would handle multiple fuels, too. Yes, even hypergolics if needed. Eventually they would standardize not on hydrogen-oxygen but methane-oxygen for ease of handling and in-space manufacture. They can even use the RL10 for this and probably retrofit upper stages for the task (eventually). <br /><br />Propellant makes up the bulk of any space mission. It is "wasted" mass in this sense. There is a silver lining, liquids are infinitely divisible. Doesn't matter if it goes 1 ton or 100 tons at a time, if there is a place to store it upstairs.<br /><br />Destinations matter. <br /><br />josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[gunsandrockets]

<The delta-v between LEO and EML1 is 0.77km/s. ><br /><br />Interesting. I had the impression it was more than that. Do you have a link handy?

 

[spacester]

It's always a good day for me when a concept which was once derided as 'decades in the future' suddenly becomes (almost) mainstream.<br /><br />The tug can't be far behind. IIRC Boeing had plans once upon a time.<br /><br />Sorry JO5H, but 0.77 km/s gets you from circular LEO of 275 km to a 2120 km circular orbit . I show 3.05 km/s needed from 275 km LEO to EML1.<br /><br />BTW . . . . I have a spreadsheet available for download, if anyone's interested. It calculates mass budgets for a staged journey from LEO to the Lunar surface. Take a look around my newly remodeled site, it's on the Lunar Lander Rover page. <br /><br />It also lets you see dV for Hohmann transfers in Earth and Lunar orbits, once you understand how things work you can get quick answers to advanced questions. If you do spreadsheets, you won't be disappointed. No user's manual, you're on your own, but it's packed with info. <div class="Discussion_UserSignature"> </div>

 

[gunsandrockets]

<I show 3.05 km/s needed from 275 km LEO to EML1.><br /><br />I thought it was something high like that. <br /><br />

 

[spacester]

That's the dV to rendezvous with an object orbiting Earth at the L1 distance. The actual number might be somewhat less than 3.05 km/s because an L point is in a little dip in the gravity field. But no matter how you go about things, you have to put energy into your orbit to climb up to L1 altitude. I'd say no less than 3.0 km/s, but I'm going to look into this a little deeper.<br /> <div class="Discussion_UserSignature"> </div>

 

[jimfromnsf]

"The delta-v between LEO and EML1 is 0.77km/s"<br /><br />I think he meant GEO

 

[holmec]

That's why a depot might not work but a permanent TLI tug would because it could rendevous with the launched tanks and stack them, as well as the payload to go to the moon. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[j05h]

<i>> I think he meant GEO</i><br /><br />No, I meant to EML1, but either misread or used a bad source (wikipedia - no comments, pls, working fast)<br /><br />Can you recommend an online source, preferably a table, of delta-v budgets? <br /><br />J <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>

 

[gunsandrockets]

<Can you recommend an online source, preferably a table, of delta-v budgets?><br /><br />Here's something...<br /><br />http://www.pma.caltech.edu/~chirata/deltav.html<br /><br />... damn, I just checked and the link doesn't seem to work anymore. I don't know if it's a temporary problem, or if the link is dead. Sorry.

 

[no_way]

http://en.wikipedia.org/wiki/Delta-v <br /><br />You used this ? whats wrong with it, why is it bad <br /><br />You can always go with:<br />http://clowder.net/hop/railroad/deltaveemap.jpg<br /><img src="/images/icons/smile.gif" />