kerbiloid Posted April 7, 2017 Share Posted April 7, 2017 1 hour ago, Veeltch said: If I'm not mistaken Falcon 9 is the most frequently flown rocket right now, isn't it? Currently - yes. Link to comment Share on other sites More sharing options...
Frybert Posted April 7, 2017 Share Posted April 7, 2017 Some more off topicness has been removed. Link to comment Share on other sites More sharing options...
tater Posted April 7, 2017 Share Posted April 7, 2017 Static fire the 26th, launch moved to the 30th. Could be the payload, but none of us will never know that because NRO, lol. Altas launch the 28th now. Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted April 7, 2017 Share Posted April 7, 2017 2 hours ago, tater said: Static fire the 26th, launch moved to the 30th. Could be the payload, but none of us will never know that because NRO, lol. Altas launch the 28th now. So Atlas pushed back too, hmm. I wonder if that's related. Maybe a range issue. Link to comment Share on other sites More sharing options...
TheEpicSquared Posted April 7, 2017 Share Posted April 7, 2017 2 hours ago, tater said: Static fire the 26th, launch moved to the 30th. Could be the payload, but none of us will never know that because NRO, lol. Altas launch the 28th now. THE 30TH!!?? Wow... that was a longer delay than I expected... I was hoping for at least 2 F9 launches this month. Oh well... I too wonder if the Altas V launch has something to do with it. Link to comment Share on other sites More sharing options...
StupidAndy Posted April 7, 2017 Share Posted April 7, 2017 I have a question so with the ITS they land the launcher, and load the propellant stage and relaunch it again, after the propellant tanker loads up the transfer stage, will they land the propellant stage as well? and are they also going to re-land the launcher as well? (I think the answer is yes) Link to comment Share on other sites More sharing options...
SpaceOdissey Posted April 7, 2017 Share Posted April 7, 2017 2 minutes ago, StupidAndy said: I have a question so with the ITS they land the launcher, and load the propellant stage and relaunch it again, after the propellant tanker loads up the transfer stage, will they land the propellant stage as well? and are they also going to re-land the launcher as well? (I think the answer is yes) Well technically... yes... I THINK. 3 minutes ago, StupidAndy said: I have a question so with the ITS they land the launcher, and load the propellant stage and relaunch it again, after the propellant tanker loads up the transfer stage, will they land the propellant stage as well? and are they also going to re-land the launcher as well? (I think the answer is yes) 2nd Quote! If you don't know this will help: Link to comment Share on other sites More sharing options...
FishInferno Posted April 8, 2017 Share Posted April 8, 2017 1 hour ago, StupidAndy said: I have a question so with the ITS they land the launcher, and load the propellant stage and relaunch it again, after the propellant tanker loads up the transfer stage, will they land the propellant stage as well? and are they also going to re-land the launcher as well? (I think the answer is yes) Yes, the crewed ITS will need to be visited 3-5 times to fully fuel it. Elon has said that he wants the ITS booster to be ready to fly within an hour of landing, so presumably you could launch the crewed ITS and several tankers all on the same booster within a day. Initially, of course, they will not likely have one hour turnaround, so the fueling process might take place over a month(s). Link to comment Share on other sites More sharing options...
tater Posted April 8, 2017 Share Posted April 8, 2017 I'll worry about ITS logistics when it's more than a powerpoint presentation with a youtube video . Link to comment Share on other sites More sharing options...
Frozen_Heart Posted April 8, 2017 Share Posted April 8, 2017 This is going to take a big chunk off payload capacity. Maybe they have decided a fully reusable Falcon Heavy is cheaper than a partially reusable Falcon 9? Link to comment Share on other sites More sharing options...
Wjolcz Posted April 8, 2017 Share Posted April 8, 2017 2 hours ago, Frozen_Heart said: This is going to take a big chunk off payload capacity. Maybe they have decided a fully reusable Falcon Heavy is cheaper than a partially reusable Falcon 9? It might be. It would make sense to sacrifice some payload capacity to recover all the stages and fairings. Especially when FH has 60(?) tonnes to LEO. Even if it gets reduced to 30 it's still a pretty good score. Especially when the next launch you only pay for the fuel (and refurbishment but I assume this will get cheaper and cheaper with time) not a whole rocket. Link to comment Share on other sites More sharing options...
Lukaszenko Posted April 8, 2017 Share Posted April 8, 2017 I'm guessing that making the 2nd stage reusable can't be worse (payload wise), but probably even much better than attaching a Dragon 2 to it, since a Dragon 2 already has all the things necessary for reusability. If my math is correct, you would then be left with a ~10,000 kg payload. Not that bad, really. It's what the original Falcon 9's payload was, except now all the hardware is reusable. Link to comment Share on other sites More sharing options...
Frozen_Heart Posted April 8, 2017 Share Posted April 8, 2017 50 minutes ago, Lukaszenko said: I'm guessing that making the 2nd stage reusable can't be worse (payload wise), but probably even much better than attaching a Dragon 2 to it, since a Dragon 2 already has all the things necessary for reusability. If my math is correct, you would then be left with a ~10,000 kg payload. Not that bad, really. It's what the original Falcon 9's payload was, except now all the hardware is reusable. Dragon 2 has other things as well such as life support and a pressure vessel for the squishy humans. Should be much lighter than that. Link to comment Share on other sites More sharing options...
magnemoe Posted April 8, 2017 Share Posted April 8, 2017 3 hours ago, Veeltch said: It might be. It would make sense to sacrifice some payload capacity to recover all the stages and fairings. Especially when FH has 60(?) tonnes to LEO. Even if it gets reduced to 30 it's still a pretty good score. Especially when the next launch you only pay for the fuel (and refurbishment but I assume this will get cheaper and cheaper with time) not a whole rocket. My take on it too, launch costs for falcon heavy is not that much higher than 9 outside of the rocket. So if they launch often and don't have to do an lot of maintenance they will save. Link to comment Share on other sites More sharing options...
IllyrianTheGreat Posted April 8, 2017 Share Posted April 8, 2017 (edited) When I am reading about reusability this is my first thought. Would it be possible to make 2 Falcon 9 cores asymmetric rocket? Edited April 8, 2017 by IllyrianTheGreat Link to comment Share on other sites More sharing options...
Skylon Posted April 8, 2017 Share Posted April 8, 2017 (edited) Does Elon plan to eventually use the Raptor engines on the F9 boosters? It would increase the efficiency and make a F9 Fuller Thrust. I still remember this picture: With what looks like the falcon XX (which is like the ITS booster/ship) having larger engines with larger thrust (raptor except the raptors are smaller) and sharing these engines with the F9/F9H. Edited April 8, 2017 by Skylon Link to comment Share on other sites More sharing options...
tater Posted April 8, 2017 Share Posted April 8, 2017 Link to comment Share on other sites More sharing options...
tater Posted April 8, 2017 Share Posted April 8, 2017 Some take home messages from the talk: Be-4 throttleable to 30%. Test fire in the next few weeks. Be-3 throttleable to 20%. 45T to LEO, 13 to GTO, both numbers conservative, they expect better. At the end, he was asked about pricing, and he stated that they plan to be market-leading in terms of cost/kg. Link to comment Share on other sites More sharing options...
cantab Posted April 8, 2017 Share Posted April 8, 2017 I doubt it. Methane is rather lower density than kerosene, so the rocket would hold less fuel unless it's substantially enlarged. And if you're going to change the engines and the structure so much, it's not really a Falcon 9 any more. Also, Falcon 9 lands on one Merlin on low thrust, one Raptor would be three times as powerful and that makes the landing require more precision. And if you replace nine Merlins with three Raptors, what does that do to your engine-out capability. No, Falcon 9 will keep using Merlins. Raptors are bigger engines for a bigger rocket. Link to comment Share on other sites More sharing options...
mikegarrison Posted April 8, 2017 Share Posted April 8, 2017 23 minutes ago, cantab said: I doubt it. Methane is rather lower density than kerosene, so the rocket would hold less fuel unless it's substantially enlarged. And if you're going to change the engines and the structure so much, it's not really a Falcon 9 any more. Also, Falcon 9 lands on one Merlin on low thrust, one Raptor would be three times as powerful and that makes the landing require more precision. And if you replace nine Merlins with three Raptors, what does that do to your engine-out capability. No, Falcon 9 will keep using Merlins. Raptors are bigger engines for a bigger rocket. Recovering from an engine out is a nice trick, but it is always far better to have fewer engines that work rather than more engines that don't always work. Engine reliability should be prioritized over engine redundancy. Link to comment Share on other sites More sharing options...
mikegarrison Posted April 8, 2017 Share Posted April 8, 2017 54 minutes ago, tater said: Some take home messages from the talk: Be-4 throttleable to 30%. Test fire in the next few weeks. Be-3 throttleable to 20%. 45T to LEO, 13 to GTO, both numbers conservative, they expect better. At the end, he was asked about pricing, and he stated that they plan to be market-leading in terms of cost/kg. Amazon deliberately priced themselves below profitability for what, a decade at least? Bezos is not afraid to lose money in order to buy market share. Link to comment Share on other sites More sharing options...
Elthy Posted April 8, 2017 Share Posted April 8, 2017 25 minutes ago, mikegarrison said: Recovering from an engine out is a nice trick, but it is always far better to have fewer engines that work rather than more engines that don't always work. Engine reliability should be prioritized over engine redundancy. A big part of SpaceX success comes from their approach of using lots of cheap engines. They "massproduce" them and thus profit from scaling effects... Link to comment Share on other sites More sharing options...
Exoscientist Posted April 8, 2017 Share Posted April 8, 2017 On 4/5/2017 at 7:05 PM, mikegarrison said: That seems unsustainable in the long run. At that rate, he'll only be able to personally fund Blue Origin for another 72 years. You left out the ironic smiley face there! Bob Clark Link to comment Share on other sites More sharing options...
Bill Phil Posted April 8, 2017 Share Posted April 8, 2017 1 hour ago, mikegarrison said: Recovering from an engine out is a nice trick, but it is always far better to have fewer engines that work rather than more engines that don't always work. Engine reliability should be prioritized over engine redundancy. What if those smaller engines are just as reliable individually than the larger ones? Then it's better to have more. Engine out is great, but too many engines can be a huge issue. Five is a good number. It certainly saved the Saturn V at least once. But engines that are too big are also problematic, like the F-1's combustion instability. We were able to make the engine work by fooling around with the injector assembly. The Russians noticed this issue and so they made multiple chambers run off of one set of pumps for that very reason. Link to comment Share on other sites More sharing options...
magnemoe Posted April 8, 2017 Share Posted April 8, 2017 4 hours ago, cantab said: I doubt it. Methane is rather lower density than kerosene, so the rocket would hold less fuel unless it's substantially enlarged. And if you're going to change the engines and the structure so much, it's not really a Falcon 9 any more. Also, Falcon 9 lands on one Merlin on low thrust, one Raptor would be three times as powerful and that makes the landing require more precision. And if you replace nine Merlins with three Raptors, what does that do to your engine-out capability. No, Falcon 9 will keep using Merlins. Raptors are bigger engines for a bigger rocket. Yes, they need an larger body for this, as i understand the raptor is designed to have an high throttle range, still it would be an issue. But it would be an new rocket, it would make some sense to give it falcon heavy capabilities for second stage recovery, you would have to re design second stage even more. Would not the raptor be serious overkill for second stage to? Link to comment Share on other sites More sharing options...
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