Author Topic: $200,000 to $300,000 per flight in fuel and oxygen versus a $60 million rocket  (Read 27940 times)

Offline guckyfan

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The second stage needs the same number of bulkheads as the first stage. It needs an RCS, it needs avionics. It needs the vacuum extension of Merlin. Cost relation is going to be much higher than 1/9.

Offline Alexsander

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The second stage needs the same number of bulkheads as the first stage. It needs an RCS, it needs avionics. It needs the vacuum extension of Merlin. Cost relation is going to be much higher than 1/9.


http://www.nasa.gov/pdf/586023main_8-3-11_NAFCOM.pdf (page 8):

(FY2010 $M)

Elements(Flight Unit)
Stage One (Including Engines)$87
Stage Two (Including Engine)$12
Fee (12.5%)$12
Program Support (10%)$4
Contingency (30% Vehicle, 10% Engine)$11
Vehicle Level Integration (8%)$5
TOTAL$131

It seems the 2nd stage is way cheaper than the 1st stage.

Offline JamesH

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The second stage needs the same number of bulkheads as the first stage. It needs an RCS, it needs avionics. It needs the vacuum extension of Merlin. Cost relation is going to be much higher than 1/9.

I would expect the avionics to be relatively cheap compared with materials cost for the stage and that of the engines, and also common between the stages. And I'd also  expect the engines to be much more expensive than the stage itself, which after all is just a bunch of aluminium welded together. RCS is also common between 1st and second stages, so should be a relatively cheap thing to make in the quantities required. 1st stage also has grid fins. But overall, the engines are the major cost of the stage, as intuition seems to intuit.

So even if the stages themselves cost the same to make, the reduction of 9 to 1 engines really does make a huge difference.

Offline Darkseraph

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The price of the fuel per flight will the be indeed $200, 000 to $300, 000 for reusable flights...almost exactly what it will be for expendable ones too! But that's not the total cost per flight, and I think anyone who believes seriously that rockets are just going to become reduced to the price it costs to fuel them has lost their freaking minds!

* I actually do believe at some stage, reusability will lower costs..but not as fast, cheaply or simply as people think it will happen, and not in the fantasy way imagined where they recover one stage intact and then 3 years later every other company goes out of business because they can't compete with Elon's secret sauce, hail Musk!

The reason for my doubts would be firstly, the second stage can't be reused for the most lucrative missions. They've given up on that. Secondly, we are not sure of the refurbishment costs until we see what happens to a recovered stage. It's an unknown. Thirdly, they won't be able to be reused as much as airplanes and operating them will be harder. Fourthly, given the history of spaceflight so far, its fair to say about 2-3% of these vehicles will blow up, which would be a disaster in modern commercial aviation. They might get better over time as more flight data is collected..or it might end up being exponentially harder to get rid of all the possible bugs and rocket reliability has diminishing returns as you try to solve all the small ones. We are not sure.

Pulling figures straight out of my super massive black hole, I'd say a reduction in price to something between $30 and $45 million is a much more likely outcome for reusable vehicles in the EELV class within the next decade, and as soon as it's proven, others will follow and try to reduce it even more but nowhere near people are projecting, like below a million. But even down to $45 million would be an amazing achievement that opens up loads of new opportunities!


 
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Offline guckyfan

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It seems the 2nd stage is way cheaper than the 1st stage.

And you give credibility to that calculation how? Given that SpaceX charges less than half the assumed total price for launches.

I would expect the avionics to be relatively cheap compared with materials cost for the stage and that of the engines, and also common between the stages. And I'd also  expect the engines to be much more expensive than the stage itself, which after all is just a bunch of aluminium welded together. RCS is also common between 1st and second stages, so should be a relatively cheap thing to make in the quantities required. 1st stage also has grid fins. But overall, the engines are the major cost of the stage, as intuition seems to intuit.

So even if the stages themselves cost the same to make, the reduction of 9 to 1 engines really does make a huge difference.

I do remember that only a short while back estimates were given that a second stage would be more expensive than a first stage. Reason, that the first stage contains no avionics, only the second stage, cost of integration is high compared to hardware. Of course they do now include avionics.

I never followed that reasoning because I was sure SpaceX avionics are not that expensive. But it seems obvious to me that a second stage must be significantly more expensive than 1/9 as per the engine count. Which fits well with the cost ratio given by Elon Musk.

Now suddenly the data given by Elon Musk are not believed and it is assumed second stages must be dirt cheap because they have only one engine. Seriously weird reasoning IMO.

Offline Mongo62

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http://www.nasa.gov/pdf/586023main_8-3-11_NAFCOM.pdf (page 8):

(FY2010 $M)

Elements(Flight Unit)
Stage One (Including Engines)$87
Stage Two (Including Engine)$12
Fee (12.5%)$12
Program Support (10%)$4
Contingency (30% Vehicle, 10% Engine)$11
Vehicle Level Integration (8%)$5
TOTAL$131

It seems the 2nd stage is way cheaper than the 1st stage.

While the listed numbers are obviously far too high, I see no reason why the 8:1 ratio between the costs for the first and second stages would not be correct. This would imply that the engines comprise 90% of the cost of the first stage and 80% of the cost of the second stage (assuming that the cost of the second stage without engine is 1/4 the cost of the first stage without engines, roughly proportional to their respective lengths).

Offline ioconnor

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I suspect SpaceX prices will always be market driven. That is they will always work at maximizing their profit based on demand and supply. So even if it were to cost SpaceX a million in fuel and operations to reuse a rocket they would never charge only 1.125 million. (Naturally if they had competition then it would be a different story.)

Offline Alexsander

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While the listed numbers are obviously far too high, I see no reason why the 8:1 ratio between the costs for the first and second stages would not be correct. This would imply that the engines comprise 90% of the cost of the first stage and 80% of the cost of the second stage (assuming that the cost of the second stage without engine is 1/4 the cost of the first stage without engines, roughly proportional to their respective lengths).

On page 9 of the same NASA's study they estimate the cost of "2 Flight Units":
First Stage: $ 109.3 M (76,17%)
Second Stage: $ 23.6 M (16,44%)
Vehicle Level Integration: $ 10.6 M (7,39%)
TOTAL for 2 rockets: $ 143.5

By this estimate the Second Stage costs 16,44% of the total. This is about 1/6.

Online llanitedave

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While the listed numbers are obviously far too high, I see no reason why the 8:1 ratio between the costs for the first and second stages would not be correct. This would imply that the engines comprise 90% of the cost of the first stage and 80% of the cost of the second stage (assuming that the cost of the second stage without engine is 1/4 the cost of the first stage without engines, roughly proportional to their respective lengths).

On page 9 of the same NASA's study they estimate the cost of "2 Flight Units":
First Stage: $ 109.3 M (76,17%)
Second Stage: $ 23.6 M (16,44%)
Vehicle Level Integration: $ 10.6 M (7,39%)
TOTAL for 2 rockets: $ 143.5

By this estimate the Second Stage costs 16,44% of the total. This is about 1/6.


I'm thinking that the numbers quoted are for the F9 v.1.0, since they're from 2010.  The engines and stages have supposedly been redesigned since then for greater economies in manufacturing, but the distribution of costs between the first and second stage should probably remain pretty similar.
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Online meekGee

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The second stage needs the same number of bulkheads as the first stage. It needs an RCS, it needs avionics. It needs the vacuum extension of Merlin. Cost relation is going to be much higher than 1/9.
True, but also does not have legs and grid fins.

The numbers above suggest 1/7 for an F9.0, so we're in the ballpark.

I would also  suggest that after modifications are made to the design after reuse kicks in, there may be items that get more expensive on S1 and less so on S2.   Right now, commonality is key, but when they are making several upper stages per week, and only the occasional lower stage (once every couple of months or so if even that), things may change.
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Online meekGee

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Just keep in mind that it was barely "decades" between Wright brother's first flight and airline-like operations....
We have had decades between Gagarin and today and I see no substantial improvement towards an airline-like operation.

And I would suggest that there is at least one major difference between the two situations:  when the Wrights first flew, there was already a large amount of traffic between most of the destinations that would later be served by air transport.  Air transport merely had to become a better way of reaching existing destinations.  In space, on the other hand, the destinations and demand for travel to them for the most part have yet to be created.
I was thinking of 5 years from now, rather than decades.

They will launch once a week just to maintain commX, plus (with reusable pricing) they'll launch the bulk of commercial satellites, a market that will grow too.

I also suspect there will be more constellations, like for example Google's imaging constellation.

An occasional manned trip around the moon might also occur by then.

So, several launches per week seems reasonable.
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Offline AdrianW

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Pulling figures straight out of my super massive black hole, I'd say a reduction in price to something between $30 and $45 million is a much more likely outcome for reusable vehicles in the EELV class within the next decade, and as soon as it's proven, others will follow and try to reduce it even more but nowhere near people are projecting, like below a million. But even down to $45 million would be an amazing achievement that opens up loads of new opportunities!
For those with access, there's some relevant info in this L2 thread.

Offline Mongo62

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On page 9 of the same NASA's study they estimate the cost of "2 Flight Units":
First Stage: $ 109.3 M (76,17%)
Second Stage: $ 23.6 M (16,44%)
Vehicle Level Integration: $ 10.6 M (7,39%)
TOTAL for 2 rockets: $ 143.5

By this estimate the Second Stage costs 16,44% of the total. This is about 1/6.

That number could only be correct if the cost of the non-engine portion of the first stage is no more than twice that of the non-engined second stage. If it is in fact half the cost, then the portion of the total manufacturing cost of the first stage that goes to the engines is 77%, and the portion of the total manufacturing cost of the second stage that goes to the engine is only 43%.

Given a total cost of the first plus second stage stack of $40 million (just a guess, but you have to leave room for such things as testing, launch operations, development costs and profit), this implies a per-engine cost of about $2.86 million, with the non-engined first stage costing about $7.6 million and the non-engined second stage (plus interstage) costing about $3.8 million.

To have the total manufacturing cost of the second stage be 1/3 of the total first-plus-second stage stack is basically impossible. Even if the non-engined second stage costs exactly the same as the non-engined first stage, the engines could constitute only 56% of the total cost of the first stage, and a mere 12% of the total cost of the second stage. In other words, the per-kg cost of the engines (probably just under 10% of the total dry mass of the second stage, and over 23% of the dry mass of the first stage, according to this website) would be not much more than the per-kg cost of the rest of the stages. This sounds extremely unlikely to me.
« Last Edit: 03/06/2015 04:05 PM by Mongo62 »

Offline AdrianW

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On page 9 of the same NASA's study they estimate the cost of "2 Flight Units":
First Stage: $ 109.3 M (76,17%)
Second Stage: $ 23.6 M (16,44%)
Vehicle Level Integration: $ 10.6 M (7,39%)
TOTAL for 2 rockets: $ 143.5

By this estimate the Second Stage costs 16,44% of the total. This is about 1/6.
It doesn't matter. It's still only an estimate by an outside entity about a different rocket (yes, the v1.0 is a different rocket from the v1.1) vs. a relatively recent statement by Elon Musk himself.

If you believe that Musk lied, please say so.

Offline john smith 19

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It doesn't matter. It's still only an estimate by an outside entity about a different rocket (yes, the v1.0 is a different rocket from the v1.1) vs. a relatively recent statement by Elon Musk himself.

If you believe that Musk lied, please say so.
Interesting PDF. I think it's the TL:DR version of the data for an OMB report regarding the cost of Commercial Crew & Cargo

The costs are those values when you put your spec for CCC into this thing called "NAFCOM" which is an industry wide cost model so you can work out how much money you'll need.

Using NASA SOP as a cost plus project gave a cost (including 2 flights) of $1.32 billion or $440m with "commercial" practices, Which IIRC was still about 100% over what SpaceX did it for.

But note at this point F9 was already flying without a dime from NASA. BTW SpaceX did supply the actual costs and it's interesting that one of the "Cost Estimating Equations" the model uses is on total number of staff (including sub contractors). Reading between the lines SpaceX's decision to make a lot of stuff in house cut the (estimated) cost a lot.

The real point of this document is that industry standard cost estimating models are widely skewed by the high proportion of cost plus projects that over run their budget, with the result that this a budget estimate generated by NAFCOM will be the figure after all those cost overruns.

You could say that NAFCOM tells you the line you can keep over running a cost plus project (from what you originally got to start the project) before Congress starts to consider cancelling the whole thing.

That of course would be a deeply cynical PoV.  :(
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Offline john smith 19

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Quote
Airliner uses about x times more/less fuel than F9.
That makes no sense. Airliners don't put payloads on orbit. Airliners provide ground to ground transportation. Airliner costs probably include crews. Rockets have ground crews. Its so different, let's not even go there.
Bono and Gatland  were making the point that the argument that space flight is expensive because it takes so much more fuel to get there (the round trip is about 21 000 miles) is bogus as the amount of energy needed per unit mass is about the same as for some long terrestrial journeys.
Quote
What matters is reducing launch costs. Reusing the first stage is a huge step forward.
Actually for a customer what matters is reducing launch prices

There's a difference.
But even down to $45 million would be an amazing achievement
True.
Quote
that opens up loads of new opportunities!
Doubtful. Although from the L2 material it seems that's around the price SpaceX is talking for a reuse.

I agree with the rest of your post.
"Solids are a branch of fireworks, not rocketry. :-) :-) ", Henry Spencer 1/28/11  Averse to bold? You must be in marketing."It's all in the sequencing" K. Mattingly.  STS-Keeping most of the stakeholders happy most of the time.

Offline Alexsander

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It doesn't matter. It's still only an estimate by an outside entity about a different rocket (yes, the v1.0 is a different rocket from the v1.1) vs. a relatively recent statement by Elon Musk himself.

If you believe that Musk lied, please say so.

Which Musk's statement are you talking about?

Offline S.Paulissen

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It doesn't matter. It's still only an estimate by an outside entity about a different rocket (yes, the v1.0 is a different rocket from the v1.1) vs. a relatively recent statement by Elon Musk himself.

If you believe that Musk lied, please say so.

Which Musk's statement are you talking about?

[Question about reusing stages and business model.] Our pricing right now assumes no reusability. None of our prices are contingent on that. Any reusability we're able to achieve would only allow us to reduce prices from where they are today. The more often we're able to fly and the more often we're able to reuse the stages and the less work they require between flights, the lower the costs can be. The boost stage is roughly 70% of the cost of a launch. So, if we're able to reuse it and refly it with minimal work between flights, and customers are comfortable with that - and it might take a few years for customers to get comfortable with that - then obviously there's as much as - ultimately - a 70% reduction from where things are today.

EDIT: emphasis added
« Last Edit: 03/06/2015 09:54 PM by Exclavion »
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Online llanitedave

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That doesn't mean the second stage is 30%.
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Offline Mongo62

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That doesn't mean the second stage is 30%.

In fact the cost of the second stage CANNOT be that high a percentage of the total manufacturing cost. If it were, the cost of the engines would end up in the negative numbers, depending on the cost ratio for the non-engined first and second stages.

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