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Leaning tower of falcon 9
JF Mezei wrote:
On 2016-06-19 11:45, Fred J. McCall wrote: Non sequitur. Go back and read what I said. Your assumptions are based on sending the barge to a failed landing and refurbiushing it after the explosion being minimal costs. I note that when called on a non sequitur response, your 'answer' is to start snipping out context. Cost of sending the barge is DIESEL FUEL. That's pretty much down in the noise. Have you LOOKED at one of these barges? Just what do you think there is for an explosion to damage? There are two cargo containers with 'support equipment'. That's it. My statement is that only accountants know this now. They have experience in how much it costs to run the barge and support ship, and they have had a few crashes to know what sort of damage is involved and how many man hours/equipment this costs. A lot of these numbers are public or easily inferred. Elon Musk in an interveiw a while back even admitted that they don't yet have all the numbers and enough data points to know whether refurbishing will be good business. The expectation is that they won't have to 'refurbish' anything. Just inspect and refly. Note that yesterday, he tweeted that he now expects 70% of landings to be succesful. But IF those statistics were broken down to 95% of ISS/LEO meissions being succesful and only 30% of GTO missions being successful, you can see that this would affect whether they bother trying to recover GTO missions to begin with. Why? I am not stating that they should or shouldn't bother. What I am saying is that they need to have statistics on how each type of mission affects recovery chances and run the numbers to see if this is a paying proposition in the long term. (and to get those numbers, they have to try as many landings as possible which is what they are doing now.) Hopefully it does turn out that the costs are low enough and success rate is high enough that they try to recover all of them. But they don't have enough numbers yet, and since the software is still evolving, the cutover between reliable landing and unreliable landing is also moving to include more "reliable" landings. Well, doh! Falcon 9 isn't a 'paper bird'. It's flying hardware. The landing part is still very much R&D. And the refurbishing of the stage 1 is also R&D. Non sequitur. But you cut all the context. The idea is that you don't need to 'refurbish' the stages. You do a quick inspection and then refly them. -- "Ignorance is preferable to error, and he is less remote from the truth who believes nothing than he who believes what is wrong." -- Thomas Jefferson |
#12
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Leaning tower of falcon 9
JF Mezei wrote:
On 2016-06-20 13:56, Fred J. McCall wrote: A lot of these numbers are public or easily inferred. So, SpaceX accounting is public ? Read what I said, yammerhead. OK, I'm going to type what follows REALLY SLOWLY. Read each sentence and actually think about it until you understand what I've said. The expectation is that they won't have to 'refurbish' anything. Just inspect and refly. NASA had the same expectation with the Shuttle too. False. NASA had no such expectation for anything that even approximated the vehicle that they actually built. The original Shuttle concept was for a much smaller vehicle with much less crossrange capability. That concept never got much beyond that stage. THAT concept was the one NASA had the low refurbishment estimates for. They NEVER had a 'zero refurbishment' expectation and they certainly never had it for the vehicle they actually designed and built. Claiming that they did is A LIE. Learn something about the actual development history of the Space Shuttle. I don't believe Musk as released any info on what's needed to get a landed Stage1 ready to fly again. And I suspect they want a few more samples back before drawing conclusions, so your conclusion that it is just "inspect and refly" is premature. It may end up as "inspect and refly". But until there is enough experience, nobody can draw that conclusion. With SpaceX we're talking about REAL HARDWARE. That hardware, unlike the Space Shuttle, was designed around the idea that it could be reflown around ten times with little to no refurbishment. SpaceX has dismantled and inspected the first booster they recovered. They have stated that it all looks clean and virtually brand new. Learn something about what SpaceX is saying. The idea is that you don't need to 'refurbish' the stages. You do a quick inspection and then refly them. At the moment, this is the dream. Whether that becomes reality depends on the outcome of the tests being done with recent launches where a stage was recovered. No. At the moment, this is the intended design goal. All evidence to date indicates that design goal is being met. Again, learn something about what SpaceX is saying. One issue is that they may find a stage to be fine and "inspect and refly" is decided but at launch, something goes wrong and they realise they forgot to inspect X for Y type of damage. That will come with experience. And fairies may **** magic dust all over things and make it all fail. Again, learn something about what SpaceX is saying. -- "Ignorance is preferable to error, and he is less remote from the truth who believes nothing than he who believes what is wrong." -- Thomas Jefferson |
#13
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Leaning tower of falcon 9
On 6/20/2016 5:30 PM, Fred J. McCall wrote:
SpaceX has dismantled and inspected the first booster they recovered. They have stated that it all looks clean and virtually brand new. Yet curiously SpaceX hasn't yet static test fired any recovered boosters. I know that SpaceX is busy trying to increase their launch tempo (and having considerable success) but this delay really is starting to get curious, particularly in the face of their success at recovery. Their stated goal was to static fire a recovered booster several times, and to do it quickly. It hasn't happened. Why not? |
#14
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Leaning tower of falcon 9
In article . com,
says... On 2016-06-20 17:30, Fred J. McCall wrote: No. At the moment, this is the intended design goal. All evidence to date indicates that design goal is being met. Evidence based on 1 recovered stage 1. You are stating that the design goal is being met based on that 1 point of data. I am stating it is too early to state that it is being met. SpaceX has recovered more than one stage. They've recovered four so far. Here is an article with a picture showing all four (the one on the right has been cleaned up a bit, but you can still see some of the soot at the top end of the stage). http://www.space.com/33102-spacex-le...-comes-ashore- photos.html You state that it can be reflow 10 times. I say that until they have take a stage and reflown it multiple times, it is too early to say how many times a stage can economically be reflown. ( refurb costs may increase with number of flights for instance). They've done extensive tests of the Merlin engines, which should be the "long pole in the tent" when it comes to reflights without refurbishment. I'm betting they'll meet that 10 flights without refurbishment goal. Perhaps not right away, but given enough time. Jeff -- All opinions posted by me on Usenet News are mine, and mine alone. These posts do not reflect the opinions of my family, friends, employer, or any organization that I am a member of. |
#15
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Leaning tower of falcon 9
In article , says...
On 6/20/2016 5:30 PM, Fred J. McCall wrote: SpaceX has dismantled and inspected the first booster they recovered. They have stated that it all looks clean and virtually brand new. Yet curiously SpaceX hasn't yet static test fired any recovered boosters. Actually, they did in January: SpaceX fire up returned Falcon 9 first stage at SLC-40 January 15, 2016 by Chris Bergin https://www.nasaspaceflight.com/2016...alcon-9-first- stage-slc-40/ I know that SpaceX is busy trying to increase their launch tempo (and having considerable success) but this delay really is starting to get curious, particularly in the face of their success at recovery. Their stated goal was to static fire a recovered booster several times, and to do it quickly. It hasn't happened. Why not? I'm betting it's the huge backlog of launches to take care of. Paying customers no doubt come first. Jeff -- All opinions posted by me on Usenet News are mine, and mine alone. These posts do not reflect the opinions of my family, friends, employer, or any organization that I am a member of. |
#16
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Leaning tower of falcon 9
JF Mezei wrote:
On 2016-06-20 17:30, Fred J. McCall wrote: No. At the moment, this is the intended design goal. All evidence to date indicates that design goal is being met. Evidence based on 1 recovered stage 1. You are stating that the design goal is being met based on that 1 point of data. I am stating it is too early to state that it is being met. You state that it can be reflow 10 times. I say that until they have take a stage and reflown it multiple times, it is too early to say how many times a stage can economically be reflown. ( refurb costs may increase with number of flights for instance). And I'm stating that you are a fool and wasting my time. -- "Ignorance is preferable to error, and he is less remote from the truth who believes nothing than he who believes what is wrong." -- Thomas Jefferson |
#17
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Leaning tower of falcon 9
Vaughn Simon wrote:
On 6/20/2016 5:30 PM, Fred J. McCall wrote: SpaceX has dismantled and inspected the first booster they recovered. They have stated that it all looks clean and virtually brand new. Yet curiously SpaceX hasn't yet static test fired any recovered boosters. I know that SpaceX is busy trying to increase their launch tempo (and having considerable success) but this delay really is starting to get curious, particularly in the face of their success at recovery. Their stated goal was to static fire a recovered booster several times, and to do it quickly. It hasn't happened. Why not? Because they're busy. Nothing 'curious' about that. -- "Some people get lost in thought because it's such unfamiliar territory." --G. Behn |
#18
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Leaning tower of falcon 9
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#20
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Leaning tower of falcon 9
On 6/20/2016 9:59 PM, Jeff Findley wrote:
Yet curiously SpaceX hasn't yet static test fired any recovered boosters. Actually, they did in January: SpaceX fire up returned Falcon 9 first stage at SLC-40 January 15, 2016 by Chris Bergin https://www.nasaspaceflight.com/2016...alcon-9-first- stage-slc-40/ Thank you, I remember that now! But that is still far different from the test they proposed, which I believe was supposed to be ten firings to demonstrate the robustness of the booster. The article only mentions one 2-second burn, and a questionable engine. Incidentally it was also supposed to be done at their new pad, but with the new "bleeding edge" super cooling equipment and procedures, I can see where that may have slipped. |
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