Power on Mars- fission is the way to go but will have to be solar initially.Need solar panels covering 4 football fields to make fuel for the trip home over 2 years, and keep dust off them.SpaceX is just offering a cheap ticket to Mars, it will take other companies, investors, governments to make everything else.
Tom's talk starting to get media attention:QuoteTop SpaceX employee throws shade at just about all of his competitorsThe price that government programs “charge for their rockets is just ridiculous.”by Eric Berger - May 14, 2017 1:24am BSThttps://arstechnica.com/science/2017/05/a-top-spacex-employee-throws-shade-at-just-about-all-of-his-competitors/
Top SpaceX employee throws shade at just about all of his competitorsThe price that government programs “charge for their rockets is just ridiculous.”by Eric Berger - May 14, 2017 1:24am BST
Given the cost goal Elon gave him for the Merlin 1D, depending on how close he got, those engines could be a whole lot cheaper than people have estimated them to be. That was a pretty seriously low price he was targeting.
I'm just glad to see that someone with so much influence in today's space development has such a huge night and day difference in attitude compared to the status quo of most of the experts on this forum.
Quote from: Daniels30 on 05/13/2017 11:34 pmMerlin 1D uses a method called “Phase shut off”, removes most valves reducing chances of failure by removing components and removing a lot of risk of a hard start.I think he means "face shutoff", meaning propellants are "shut off" at the injector face.See e.g. http://www.rocket-propulsion.info/resources/articles/TRW_PINTLE_ENGINE.pdf.
Merlin 1D uses a method called “Phase shut off”, removes most valves reducing chances of failure by removing components and removing a lot of risk of a hard start.
And, uh, I’ve seen that hurt us before, I’ve seen that fail, but I’ve also seen— where nobody thought it would work— it was the right decision. It was the harder way to do it, but in the end, it was the right thing. One of the things that we did with the Merlin 1D was; he kept complaining— I talked earlier about how expensive the engine was. <inaudible> [I said,] “[the] only way is to get rid of all these valves. Because that’s what’s really driving the complexity and cost.” And how can you do that? And I said, “Well, on smaller engines, we’d go phase-shutoff, but nobody’s done it on a really large engine. It’ll be really different.” And he said, “We need to do phase-shutoff. Explain how that works?” So I drew it up, did some, you know, sketches, and said “here’s what we’d do,” and he* said “That’s what we need to do.” And I advised him against it; I said it’s going to be too hard to do, and it’s not going to save that much. But he made the decision that we were going to do phase-shutoff.So we went and developed that engine; and it was hard. We blew up a lot of hardware. And we tried probably tried a hundred different combinations to make it work; but we made it work.
Quote from: FutureSpaceTourist on 05/14/2017 05:31 amTom's talk starting to get media attention:QuoteTop SpaceX employee throws shade at just about all of his competitorsThe price that government programs “charge for their rockets is just ridiculous.”by Eric Berger - May 14, 2017 1:24am BSThttps://arstechnica.com/science/2017/05/a-top-spacex-employee-throws-shade-at-just-about-all-of-his-competitors/Eric is just highliting the controversial stuff of a very interesting interview. It does not help to have more of these in the future. The foldable legs, F9 24 hour turn around in few months (as a matter of HR costs, not much on time), Tesla factory using coke manufacturing as a model (physical limits of machinery), Merlin D strategy.... are FMPOV much more interesting parts of the interview. Don't let the reality spoil a good headline.
One nugget I found interesting was when he was talking about the CommX constellation(s), he said something to the effect, 'Now imagine that you could deploy these with a rocket that can put hundreds of tons into orbit at a time...'. I guess that solidly confirms SpaceX's plans to use the ITS (as opposed to, say, FH) as the main vehicle to deploy CommX. Though that presents a bit of chicken/egg problem, as I think Musk had previously indicated that they needed CommX revenues to help pay development costs for ITS.
Quote from: GORDAP on 05/14/2017 01:09 pmOne nugget I found interesting was when he was talking about the CommX constellation(s), he said something to the effect, 'Now imagine that you could deploy these with a rocket that can put hundreds of tons into orbit at a time...'. I guess that solidly confirms SpaceX's plans to use the ITS (as opposed to, say, FH) as the main vehicle to deploy CommX. Though that presents a bit of chicken/egg problem, as I think Musk had previously indicated that they needed CommX revenues to help pay development costs for ITS.Unless constellation 2.0 will use much larger satellites, but still as many.Remember the statistics on how fast data traffic is growing, and factor in self driving cars and other upcoming developments, and constellation capability will have to grow accordingly...
There wasn't actually a lot new in here. A lot of the stuff was extrapolatable.A lot of the "new" content is simply taking stuff Musk has already said seriously.
His examples about the Merlin have some interesting numbers:About 1000 lbs engine mass. Roughly 450 kg, which is a bit lower than the previous estimates I've seen.About 800 lbs/s propellant mass flow rate. That's about 360 kg/s, which is quite a bit higher than the 275 to 300 kg/s typically quoted for Merlin.About 10,500 ft/s exhaust velocity. He also says about Mach 10 exhaust velocity. Those are 3200 and 3400 m/s or 325/345 second ISP. These don't add up to the stated thrust of Falcon 9, which is 7606 kN. With those flow rates and velocities it would be 10000 kN or 11000 kN.But maybe Merlin is considerably more capable than we expected?
Quote from: envy887 on 05/14/2017 02:21 pmHis examples about the Merlin have some interesting numbers:About 1000 lbs engine mass. Roughly 450 kg, which is a bit lower than the previous estimates I've seen.About 800 lbs/s propellant mass flow rate. That's about 360 kg/s, which is quite a bit higher than the 275 to 300 kg/s typically quoted for Merlin.About 10,500 ft/s exhaust velocity. He also says about Mach 10 exhaust velocity. Those are 3200 and 3400 m/s or 325/345 second ISP. These don't add up to the stated thrust of Falcon 9, which is 7606 kN. With those flow rates and velocities it would be 10000 kN or 11000 kN.But maybe Merlin is considerably more capable than we expected?It seemed like he was just pulling approximate numbers off the cuff. I would not read too much into that.
Quote from: Basto on 05/14/2017 03:36 pmQuote from: envy887 on 05/14/2017 02:21 pmHis examples about the Merlin have some interesting numbers:About 1000 lbs engine mass. Roughly 450 kg, which is a bit lower than the previous estimates I've seen.About 800 lbs/s propellant mass flow rate. That's about 360 kg/s, which is quite a bit higher than the 275 to 300 kg/s typically quoted for Merlin.About 10,500 ft/s exhaust velocity. He also says about Mach 10 exhaust velocity. Those are 3200 and 3400 m/s or 325/345 second ISP. These don't add up to the stated thrust of Falcon 9, which is 7606 kN. With those flow rates and velocities it would be 10000 kN or 11000 kN.But maybe Merlin is considerably more capable than we expected?It seemed like he was just pulling approximate numbers off the cuff. I would not read too much into that.TM breathes this stuff. I'd take him literally before believing our numbers to the slightest degree.
Quote from: meekGee on 05/14/2017 01:19 pmQuote from: GORDAP on 05/14/2017 01:09 pmOne nugget I found interesting was when he was talking about the CommX constellation(s), he said something to the effect, 'Now imagine that you could deploy these with a rocket that can put hundreds of tons into orbit at a time...'. I guess that solidly confirms SpaceX's plans to use the ITS (as opposed to, say, FH) as the main vehicle to deploy CommX. Though that presents a bit of chicken/egg problem, as I think Musk had previously indicated that they needed CommX revenues to help pay development costs for ITS.Unless constellation 2.0 will use much larger satellites, but still as many.Remember the statistics on how fast data traffic is growing, and factor in self driving cars and other upcoming developments, and constellation capability will have to grow accordingly...Admittedly, it's been a while since I last looked through the FCC database, but I don't think they've even approved constellation 1.0. All the spacecraft general physical details, nominal orbital elements for each plane, RF characteristics at ground level for each altitude, etc. have to be detailed by the applicant, reviewed by the FCC (and arguably the ITU if service is being performed outside of FCC jurisdiction), and then approved before the constellation can begin operating.If SpaceX is going to massively revise the plans for their satellites, there will be a several year regulatory lag from the time they make their plans to the time the can make good on those plans ... I don't think SpaceX is the kind of organization that likes being behind that kind of curve.
Quote from: Jimmy Murdok on 05/14/2017 08:15 amQuote from: FutureSpaceTourist on 05/14/2017 05:31 amTom's talk starting to get media attention:QuoteTop SpaceX employee throws shade at just about all of his competitorsThe price that government programs “charge for their rockets is just ridiculous.”by Eric Berger - May 14, 2017 1:24am BSThttps://arstechnica.com/science/2017/05/a-top-spacex-employee-throws-shade-at-just-about-all-of-his-competitors/Eric is just highliting the controversial stuff of a very interesting interview. It does not help to have more of these in the future. The foldable legs, F9 24 hour turn around in few months (as a matter of HR costs, not much on time), Tesla factory using coke manufacturing as a model (physical limits of machinery), Merlin D strategy.... are FMPOV much more interesting parts of the interview. Don't let the reality spoil a good headline.Yes, Eric is doing a huge disservice to all of space media reporting by posting such absurd comments. He should retract such articles. He's writing hit pieces to get clicks rather than to actually inform. Shame on him.