Author Topic: Refurbishment of Used Stages/Vehicles  (Read 211348 times)

Offline Kabloona

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Re: Refurbishment of Used Stages/Vehicles
« Reply #160 on: 01/12/2016 10:31 PM »
Quote
Because apart from the engines, it's a similar structure, similar fuel, similar size...  It can't be THAT different. 

I'd be more inclined to agree if you were talking about *mass* ratios, but you're not.

You're talking about *cost* ratios of completely different components on a completely different rocket. How is the cost of one RD-180 related to the cost of nine M1D's? Not to mention different production processes for tanks, etc.

Apples and oranges.
Both are fruit...  Some things are similar.

If the engines are $15M, what costs $45M?

The tanks? The Atlas cost breakdown doesn't apply directly, but it gives you an idea...

The answer is probably along the lines of what JamesH wrote above. The $1.5M engine cost is probably an "unburdened" cost number, ie only *direct* labor and materials to build that one item, without any overhead.

But the total $60M vehicle cost figure Elon refers to has to be a partially or fully burdened number including overhead of facilities, support and admin staff, etc, etc.

So if you assume a 70/30 cost split between S1 and S2, say it's $42M partially or fully burdened cost for S1, a lot of which is overhead. Subtract maybe $12M overhead and you're left with $30M direct labor and materials costs, half of which is for 9 engines, and then you get splits closer to ULA's pie chart, with F9's making up 50% of S1 *direct* costs.

Or, put another way, if you burdened that F9 engine proportionally with overhead, I'm betting the number would be more than $1.5M and the proportions would tilt towards ULA's numbers.
« Last Edit: 01/12/2016 10:38 PM by Kabloona »

Offline meekGee

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Re: Refurbishment of Used Stages/Vehicles
« Reply #161 on: 01/12/2016 10:42 PM »
Quote
Because apart from the engines, it's a similar structure, similar fuel, similar size...  It can't be THAT different. 

I'd be more inclined to agree if you were talking about *mass* ratios, but you're not.

You're talking about *cost* ratios of completely different components on a completely different rocket. How is the cost of one RD-180 related to the cost of nine M1D's? Not to mention different production processes for tanks, etc.

Apples and oranges.
Both are fruit...  Some things are similar.

If the engines are $15M, what costs $45M?

The tanks? The Atlas cost breakdown doesn't apply directly, but it gives you an idea...

The answer is probably along the lines of what JamesH wrote above. The $1.5M engine cost is probably an "unburdened" cost number, ie only *direct* labor and materials to build that one item, without any overhead.

But the total $60M vehicle cost figure Elon refers to has to be a partially or fully burdened number including overhead of facilities, support and admin staff, etc, etc.

So if you assume a 70/30 cost split between S1 and S2, say it's $42M partially or fully burdened cost for S1, a lot of which is overhead. Subtract maybe $12M overhead and you're left with $30M direct labor and materials costs, half of which is for 9 engines, and then you get splits closer to ULA's pie chart, with F9's making up 50% of S1 *direct* costs.

Or, put another way, if you burdened that F9 engine proportionally with overhead, I'm betting the number would be more than $1.5M and the proportions would tilt towards ULA's numbers.

With that I agree - there's a huge amount of wiggle room when defining cost, especially when you're vertically integrated, since you've invested upfront in order to make the marginal cost low.

But I still say the Atlas slide is relevant :)
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Offline Arb

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Re: Refurbishment of Used Stages/Vehicles
« Reply #162 on: 01/13/2016 12:07 AM »
This means that no matter how many uses occur even if it is only 2, the result is a price reduction over that of a non-reusable version of an F9.
That fits with what Musk said. When asked recently how many reuses of F9 S1 were needed to make it financially viable he replied "one".

Don't remember exactly where that was, maybe the post landing telecon. Certainly post landing. It was one of those little throw away remarks of his that people tend to ignore because confirmation bias.

Offline jg

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Re: Refurbishment of Used Stages/Vehicles
« Reply #163 on: 01/13/2016 02:02 AM »
Well if the engines are ~$1.5M, and if the Atlas slide is correct, than the F9 does not cost $60M. 

So something's gotta give.

It's an Atlas slide. Why would you assume F9 has identical cost breakdowns? It's a completely different vehicle.
Because apart from the engines, it's a similar structure, similar fuel, similar size...  It can't be THAT different.   If the Merlins are 1.5 Million, then the engine stack is 15M.  So the structures would have to be some 30M to get the entire rocket to 60M.   

That's very far from the Atlas breakdown...  2:1 instead of 1:2....

Yes, it can be very different. For one simple example that jumps out from the chart, I expect the cost of avionics is very different, and seems to be a good chunk of ULA's costs, by the pie chart shown.

ULA uses typical radiation resistant aerospace components and systems; SpaceX uses pretty COTS components for its systems and software, getting reliability by redundancy in the systems (many CPU's, etc), running much more modern software.  Given the cost of those modern components (which are far faster than anything you can get "radiation hardened"), I don't understand how to spend the kind of money that ULA current has to spend, despite having to have that redundancy; modern semiconductor technology and Moore's law being what it has been. SpaceX gave a talk at a Linux conference a few years ago describing (to the extent that the export control laws allow) what they were doing in their systems.

Sometimes, by revisiting systems from scratch, you can get to a very different (better) point that following the path of "incremental improvement".  Clean sheets can be a real advantage; but you don't get them very often.  SpaceX did a "clean sheet" on most everything.

So don't presume the actual costs in the different rockets are "the same", unless you are comparing fundamental costs (e.g. propellants, or N kilograms of aluminum alloy)...  And one of Musk's strengths is that he thinks terms of those fundamental costs, rather than what people have traditionally paid....




Offline meekGee

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Re: Refurbishment of Used Stages/Vehicles
« Reply #164 on: 01/13/2016 02:42 AM »
Well if the engines are ~$1.5M, and if the Atlas slide is correct, than the F9 does not cost $60M. 

So something's gotta give.

It's an Atlas slide. Why would you assume F9 has identical cost breakdowns? It's a completely different vehicle.
Because apart from the engines, it's a similar structure, similar fuel, similar size...  It can't be THAT different.   If the Merlins are 1.5 Million, then the engine stack is 15M.  So the structures would have to be some 30M to get the entire rocket to 60M.   

That's very far from the Atlas breakdown...  2:1 instead of 1:2....

Yes, it can be very different. For one simple example that jumps out from the chart, I expect the cost of avionics is very different, and seems to be a good chunk of ULA's costs, by the pie chart shown.

ULA uses typical radiation resistant aerospace components and systems; SpaceX uses pretty COTS components for its systems and software, getting reliability by redundancy in the systems (many CPU's, etc), running much more modern software.  Given the cost of those modern components (which are far faster than anything you can get "radiation hardened"), I don't understand how to spend the kind of money that ULA current has to spend, despite having to have that redundancy; modern semiconductor technology and Moore's law being what it has been. SpaceX gave a talk at a Linux conference a few years ago describing (to the extent that the export control laws allow) what they were doing in their systems.

Sometimes, by revisiting systems from scratch, you can get to a very different (better) point that following the path of "incremental improvement".  Clean sheets can be a real advantage; but you don't get them very often.  SpaceX did a "clean sheet" on most everything.

So don't presume the actual costs in the different rockets are "the same", unless you are comparing fundamental costs (e.g. propellants, or N kilograms of aluminum alloy)...  And one of Musk's strengths is that he thinks terms of those fundamental costs, rather than what people have traditionally paid....

Except that skews the comparison even further...   If F9s avionics is cheaper, that would require an extraordinarily expensive tank structure to even come close....

Something's got to give, and I'm buying into the "nuance" the Kabloona brought up.
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Offline john smith 19

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Re: Refurbishment of Used Stages/Vehicles
« Reply #165 on: 01/13/2016 11:54 AM »
The answer is probably along the lines of what JamesH wrote above. The $1.5M engine cost is probably an "unburdened" cost number, ie only *direct* labor and materials to build that one item, without any overhead.

But the total $60M vehicle cost figure Elon refers to has to be a partially or fully burdened number including overhead of facilities, support and admin staff, etc, etc.

So if you assume a 70/30 cost split between S1 and S2, say it's $42M partially or fully burdened cost for S1, a lot of which is overhead. Subtract maybe $12M overhead and you're left with $30M direct labor and materials costs, half of which is for 9 engines, and then you get splits closer to ULA's pie chart, with F9's making up 50% of S1 *direct* costs.

Or, put another way, if you burdened that F9 engine proportionally with overhead, I'm betting the number would be more than $1.5M and the proportions would tilt towards ULA's numbers.
In accountancy this is the "gross profit" and the "net profit"
Gross pro is turnover minus the direct costs to make the stuff you're selling.
Net profit is gross profit minus all the indirect costs, factory electricity, catering etc.

On that basis Musk is saying his net profit, the pure uncommitted stuff you can use to pay down debt, fund new development or distribute to stockholders as dividends, is about 2%.
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Offline john smith 19

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Re: Refurbishment of Used Stages/Vehicles
« Reply #166 on: 01/13/2016 12:03 PM »

ULA uses typical radiation resistant aerospace components and systems; SpaceX uses pretty COTS components for its systems and software, getting reliability by redundancy in the systems (many CPU's, etc), running much more modern software.  Given the cost of those modern components (which are far faster than anything you can get "radiation hardened"), I don't understand how to spend the kind of money that ULA current has to spend, despite having to have that redundancy; modern semiconductor technology and Moore's law being what it has been. SpaceX gave a talk at a Linux conference a few years ago describing (to the extent that the export control laws allow) what they were doing in their systems.
The cost for rad hard electronics is staggering, but I think people exaggerate it given the relatively small proportion of the hardware that uses it.

The only data point on this I have was that BAe supplied a rad hard PowerPC  board to NASA for one of the Mars rovers and the whole board (I don't think they will sell you the chip itself) ran about $100 000.

But you do get things like guaranteed frozen designs (no unmentioned process tweaks to call unexpected failures) and spare parts availability for a decade (of course swapping out a failed board on Mars is down to the customer.   :) ).

But IIRC ULA ELV's run with the USAF 1750A architecture developed in the 1970's, although probably with the MMU option to give it the full 1MB of addressable main memory

I'm not sure what SX ARM & 8051 based boards cost (this is from memory) but I'm guessing quite a bit less on parts cost unless SX insist on their own F9-ARM chip with their own special set of peripherals.
This seems very much against the spirit of using COTS parts in clever ways to give good radiation tolerance at reasonable costs.

Note that a decent modern ERP system should be able to track parts well enough that any systematic failure (due to say a process tweak in the wafer fab causing all parts to fail) should be quite easy to detect and track. The other issue is the dev tool chain. Both ARM and 8051 remain mainstream but the 1750A is niche.

The issue is not that you can't get compilers to generate code (AFAIK it's still an option, but I'm not sure for how much longer in GCC[EDIT Ooops, should have checked that. No longer available] ), but who's got assembler skills in this to get a run time up and running? Or when you run out of (equally expensive) main memory and have to re-code something in assembler to shoehorn it in?

I don't think the rad hard semiconductors are that big a deal but the indirect costs associated with them could be.  :(

One of those sneaky costs that people don't fully anticipate until it bites.

This will all get much more serious for vehicles going to Mars, all of which will leave even the limited protection of the Earth's magnetic field. SX may have to go the full rad hard route for that, but that's probably 10 years ahead. [EDIT Which is not to say that someone within SX is not already working the issues to see what they could get away with.

Now what (if any) foundries offer rad hard processes that could host an ARM? ]
« Last Edit: 01/13/2016 10:03 PM by john smith 19 »
BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C apply. Believe no one. Run your own numbers. So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

Offline CuddlyRocket

Re: Refurbishment of Used Stages/Vehicles
« Reply #167 on: 01/13/2016 11:53 PM »
This will all get much more serious for vehicles going to Mars, all of which will leave even the limited protection of the Earth's magnetic field. SX may have to go the full rad hard route for that, but that's probably 10 years ahead. [EDIT Which is not to say that someone within SX is not already working the issues to see what they could get away with.

They may have to, but I imagine the first thing they'll try is additional redundancy. But I agree that someone within SpaceX will be working this, though I suspect the FH will be throwing stuff to Mars well within 10 years.

Offline Robotbeat

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Re: Refurbishment of Used Stages/Vehicles
« Reply #168 on: 01/14/2016 12:48 AM »
NASA likes to keep Mars well-stocked in robots, so SpaceX would have to be pretty much dead for them not to launch SOMETHING to Mars in the next 10 years.
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Offline john smith 19

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Re: Refurbishment of Used Stages/Vehicles
« Reply #169 on: 01/14/2016 08:13 AM »
They may have to, but I imagine the first thing they'll try is additional redundancy. But I agree that someone within SpaceX will be working this, though I suspect the FH will be throwing stuff to Mars well within 10 years.
Quite likely but I think they'll be a rad level where every processor is in the process of reboot so none is processing any workload.

Shielding would be another option, say a chunk of plastic (high H atom density)

OTOH it's possible that there would not be that much processing to do during Mars cruise, so you could drop the clock frequency 10x or even 100x, giving time for charged particle events to be smothered by the longer time periods of each clock cycle.  That's a bit of speculation.

TBH I'm kind of surprised no one's done a rad hard ARM. It seems the ESA went with the SPARC architecture and the latest generation US systems have gone with the PowerPC, presumably due to IBM's involvement with defense and space processors.

Sure rad hard is a niche market but I'll bet the ARM developer pool is several times the size of either the PowerPC or SPARC due to it's huge penetration of the embedded market
BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C apply. Believe no one. Run your own numbers. So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

Offline oldAtlas_Eguy

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Re: Refurbishment of Used Stages/Vehicles
« Reply #170 on: 01/14/2016 09:29 PM »
Considering SpaceX just hot fired the recovered stage at SLC-40 this speaks to the cost of refurbishment  for a stage to be almost nil on the order of less than $2M toward an amount of $.5M.

What does that do to the reuse price of a F9/FH?

Online abaddon

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Re: Refurbishment of Used Stages/Vehicles
« Reply #171 on: 01/14/2016 09:46 PM »
Considering SpaceX just hot fired the recovered stage at SLC-40 this speaks to the cost of refurbishment  for a stage to be almost nil on the order of less than $2M toward an amount of $.5M.

What does that do to the reuse price of a F9/FH?
You're jumping the gun just a little bit:
- We don't know if the static fire was successful
- We don't know if a launch would be successful
I would agree it's a very positive data-point in the direction of being able to reuse the stage with little to no refurbishment, but we're not quite there yet.

Offline sanman

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Re: Refurbishment of Used Stages/Vehicles
« Reply #172 on: 01/15/2016 01:17 AM »
Presumably, whatever knowledge SpaceX does acquire in terms of what components erode fastest and require the most frequent monitoring and replacement, will be kept a trade secret by them, since this would be the key to maintaining their 'first mover advantage'. So it seems doubtful that they would reveal/publish/comment on this stuff  much, when it becomes part of the bread-and-butter of their business model.

But perhaps we'll be able to glean information from any upcoming design changes which may result from their knowledge gained from reusable flights.


« Last Edit: 01/15/2016 01:19 AM by sanman »

Offline john smith 19

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Re: Refurbishment of Used Stages/Vehicles
« Reply #173 on: 01/15/2016 10:42 AM »
Considering SpaceX just hot fired the recovered stage at SLC-40 this speaks to the cost of refurbishment  for a stage to be almost nil on the order of less than $2M toward an amount of $.5M.

What does that do to the reuse price of a F9/FH?
Not a lot.   :( See my costing game for details.

While you're throwing away a whole stage to do reuse the second biggest factor is how many times you're reusing you're 1st stage. Lowering the cost of new upper stages is a good move too (while retaining the same payload and not costing too much capital to implement, which is what makes it very tricky  :( ) , but it's likely whatever you do to lower the upper stage cost you can apply to the lower stage as well.

Which begs the question why didn't you make those cost reductions already?

The 800lb gorilla here remains can you cut customer prices enough to stimulate demand enough to increase your net profit.

IOW if you cut prices 50% (needing 4 reuses by my estimate), does your business double (or more)?
People are hoping that will happen but AFAIK historical data says that's just not enough, and remember SX have still announced no semireusable pricing.

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Offline john smith 19

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Re: Refurbishment of Used Stages/Vehicles
« Reply #174 on: 01/15/2016 10:47 AM »
OT I'm planning my next version of my costing game for F9SR, MCT & Skylon.

So far I've added a cell showing pricing in terms of multiples of propellant cost but I'd be interested if anyone has any other features they'd like. At present it has a "profit margin" cell, but I'm considering splitting that into "Gross" and "Net" options. [EDIT TBH the "Design your rocket" tab has had little work done on it. I'm wondering if it should remain in]
« Last Edit: 01/15/2016 11:00 AM by john smith 19 »
BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C apply. Believe no one. Run your own numbers. So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

Offline watermod

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Re: Refurbishment of Used Stages/Vehicles
« Reply #175 on: 01/15/2016 05:38 PM »
Presumably, whatever knowledge SpaceX does acquire in terms of what components erode fastest and require the most frequent monitoring and replacement, will be kept a trade secret by them, since this would be the key to maintaining their 'first mover advantage'. So it seems doubtful that they would reveal/publish/comment on this stuff  much, when it becomes part of the bread-and-butter of their business model.

But perhaps we'll be able to glean information from any upcoming design changes which may result from their knowledge gained from reusable flights.
If delays were not so common with SpaceX I would suspect the recent changes in launch dates were based off something SpaceX saw in the returned first stage.   
From Salo:
Quote
NET February 6 - SES-9 - Falcon 9 FT - Canaveral SLC-40 (or late NET January 23)
NET February 7 March 20 - Dragon SpX-8 (CRS8), BEAM (Bigelow Expandable Activity Module) - Falcon 9 FT - Canaveral SLC-40 - 04:20 21:01
1st quarter NET February March (TBD) - Eutelsat 117 West B (Satmex 9), ABS 2A - Falcon 9 FT - Canaveral SLC-40
NET 1st quarter February March - JCSat-14 - Falcon 9 FT - Canaveral SLC-40
NET February March - AMOS 6 - Falcon 9 FT - Canaveral SLC-40 (or midyear)
March 21 NET April - Dragon SpX-9 (CRS9) - Falcon 9 FT - Canaveral SLC-40 ~04:00
spring April-May - FORMOSAT 5, SHERPA SSO: Arkyd-6, CNUSail 1, KAUSAT 5, SIGMA, CANYVAL-X 1, CANYVAL-X 2, STEP Cube [/qoute]

Offline sanman

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Re: Refurbishment of Used Stages/Vehicles
« Reply #176 on: 01/16/2016 06:15 AM »
The recovered booster stage was test-fired and apparently one of the 9 engines showed thrust fluctuations:

http://www.usatoday.com/story/news/nation-now/2016/01/15/spacex-tests-engines-landed-falcon-rocket/78886838/

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Later Friday, SpaceX CEO Elon Musk reported on Twitter that one of the outer Merlin engines had not performed perfectly.

“Conducted hold-down firing of returned Falcon rocket,” said Musk. “Data looks good overall, but engine 9 showed thrust fluctuations.”

Musk said inspections would quickly investigate if debris had gotten into the engine.

I wonder which one showed the anomalies and why. I certainly hope it wasn't the central one.

Hypothetically, if it does indeed turn out that the malfunctioning engine did in fact ingest some debris, then how did that debris get in there? What kind of remedy could be taken - just clean up the landing pad more? I thought that having a landing pad would automatically avoid debris.

Offline Hauerg

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Re: Refurbishment of Used Stages/Vehicles
« Reply #177 on: 01/16/2016 06:21 AM »
According to Elons tweet it was NOT the center engine.

Offline Hotblack Desiato

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Re: Refurbishment of Used Stages/Vehicles
« Reply #178 on: 01/16/2016 07:51 AM »
It would be interesting, if it was one of the two other engines, which had to perform the retroboost.

Does anyone have an idea how much work is required to replace an engine?

If they have plenty of them due to reuse of rocketstages, they could replace damaged engines and refurbish them seperately.

Offline Rocket Science

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Re: Refurbishment of Used Stages/Vehicles
« Reply #179 on: 01/16/2016 08:01 AM »
Thanks for the update Chris!  :) This would be the first time a rocket engine that made it to space has been re-fired on a vehicle without refurbishment first. Unless they did it during the X-15 program or Shuttle... It's the wee hours of the morning here so feel free to correct me... ;D
« Last Edit: 01/16/2016 01:45 PM by Rocket Science »
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