FYI: Cost of Rocket Fuel

[radarredux]

From time to time someone brings up the cost of fuel for rockets. I heard a data point today, and I thought I would post it.<br /><br />According to Elon Musk on The Space Show<br />http://archive.thespaceshow.com/shows/343-BWB-2005-05-31.mp3<br /><br />the cost of fuel for the Falcon (Falcon "1" I believe) was $30,000 -- what he called a rounding error. Indeed, with the advertised cost for the Falcon 1 at $5.9 million, the cost of fuel is only 0.5% of the cost.

 

[aaron38]

That's why reusable rockets and SSTO continue to be the great dream.<br /><br />People see those fuel numbers and dream. If an RLV had a truly gas-n-go turnaround, space access would be dirt cheap.

 

[grooble]

So why do rockets cost so much?

 

[blairf]

Volume

 

[grooble]

The sheets of metal?<br /><br />

 

[radarredux]

> <i><font color="yellow">So why do rockets cost so much?</font>/i><br /><br />Paperwork?</i>

 

[grooble]

Does anyone know?

 

[henryhallam]

I think the majority of the costs are labour in design/development, labour in production, and labour in launch ops.

 

[nacnud]

Thats LOX/Kerosen, what about LOX/LH?

 

[radarredux]

> <i><font color="yellow">Does anyone know?</font>/i><br /><br />You can listen to the audio broadcast posted at the beginning of the thread. An often cited reason is that SpaceX designed their system so that an army of people are not needed. They also have a reusable first stage which helps some (the DOD has also hyped the idea of "two-stage to orbit" where the first stage (hypersonic plane, large booster, whatever) is reusable). But Musk mentioned in the broadcast (repeated on their web site) is that there is no single silver bullet -- they are driving down costs at every stage.<br /><br />Here is some text from SpaceX's FAQ:<br /><blockquote><font class="small">In reply to:</font><hr /><p>The cost of a rocket is driven by five factors: overhead, propulsion, structures, avionics and launch operations. SpaceX has a flat management structure and singular product focus, resulting in lower overhead costs than other launch vehicle providers and a significant cost advantage for any given rocket design.<br /><br />Regarding propulsion, structures and avionics, Falcon has the advantage of being a clean sheet design focused purely on reliability & cost (we view two as inseparable) and the first rocket developed in the 21 st century, taking advantage of the latest technologies. Through countdown automation and simplicity of design, our rocket requires an order of magnitude smaller launch crew than other US rockets.<br /><br />While we have many original innovations and patents pending on elements of the vehicle, there is no single silver bullet breakthrough responsible for our low costs (just as there is no single reason why Southwest Airlines is so much more cost efficient than other airlines).<p><hr /></p></p></blockquote><br /><br />One other note: Musk said he has <i>heard</i> that refurbishing the Shuttle's SRBs between launches cost about 90% of a new SRB, so there isn't a lot saved on that part (any truth SG?).</i>

 

[drwayne]

"Using the word "fuel" for "propellant" (oxidizer and fuel) is like fingernails on a black board to me."<br /><br />It gets even harder when you have something like the FLOX we were talking about earlier - as it is an oxidizer - and more.<br /><br />Of course, I remember seeing a quote somewhere describing IRFNA as not so much a chemical, but a chemical system.<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[drwayne]

BFRCS! Run for your lungs!<br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[rybanis]

What does the F do to the oxidiser? Give it a little extra kick? <div class="Discussion_UserSignature"> </div>

 

[henryhallam]

<font color="yellow"><br />What does the F do to the oxidiser? Give it a little extra kick?<br /></font><br /><br />Basically, yes. My chem isn't brilliant but I think it is because F has a more negative redox potential than oxygen, which both makes the reaction more likely to take place and means that more energy is released per mole of reactants. Also, the F-F bond is weaker than the O=O bond so less energy needs to be put in (from the general heat of the surroundings) to break apart the oxidiser molecules than with oxygen, which again results in more net energy releasted per reaction.

 

[holmec]

lol, retirement funds. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[drwayne]

Background information:<br /><br />http://yarchive.net/space/rocket/fuels/fluorine.html<br /><br />http://yarchive.net/explosives/clf5.html<br /><br />Wayne<br /><br /> <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[najab]

Silly question - if you use FLOX/LH2 doesn't that mean that some of the exhaust will be hydrofluoric acid? Very bad stuff!

 

[drwayne]

Yes it does mean that.<br /><br />Early in my career, I did a lot of crystal growth with quartz ampules, and HF was something we used as an etchant in the cleaning process.<br /><br />Fortunately that stuff, and the bromine, methanol, acetone, tolulene, mercury, cadmium, tellurium etc. didn't effect me a bit. But you want to know what really upsets me? You want to know what really makes me sick to my stomach? Its watching you stuff your face with those hot dogs, nobody, and I mean nobody eats ketchup on a hot dog...oops...slippled into Dirty Harry movie playback mode there... <img src="/images/icons/wink.gif" /><br /><br />Wayne <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[dragon04]

"So why do rockets cost so much?"<br /><br />I think that an unhealthy portion of the cost is due to the Government itself.<br /><br />It costs a ton of money to just meet government specs when you sell them something.<br /><br />Private enterprise isn't hamstrung by all thoses costs if they are manufacturing a rocket for its own use.<br /> <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>

 

[vogon13]

Seems like no shuttle is launched until the amount of paperwork for that flight equals the weight of the fully fueled stack.<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>