tater Posted February 12, 2018 Share Posted February 12, 2018 https://twitter.com/elonmusk/status/963103592881168384?ref_src=twcamp^share|twsrc^m5|twgr^email|twcon^7046|twterm^0 Quote Link to comment Share on other sites More sharing options...
insert_name Posted February 12, 2018 Share Posted February 12, 2018 https://twitter.com/elonmusk/status/963092110994886656?s=20 Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted February 12, 2018 Share Posted February 12, 2018 9 minutes ago, insert_name said: https://twitter.com/elonmusk/status/963092110994886656 Snarky. 1 hour ago, tseitsei89 said: What I would like to see is a clear comparison between different versions of atlas, delta iv, F9 and FH. How much they cost (recoverable and expendaple in falcon cases) and how much payload they can deliver to LEO and GTO. Googling this gave me a whole bunch of widely varying results, especially for the cost part... I've been using some rocket science and some published figures to get good estimates on this. I'll keep you posted. Quote Link to comment Share on other sites More sharing options...
PB666 Posted February 12, 2018 Share Posted February 12, 2018 As reported here earlier today the Vulcan Rocket design has its problems. The RL10C engines (smaller nozzle) they want to replace the RL10b-2 engine with have not yet been developed. It has to hurt ULA. FH is here, now, and Vulcan is at least 3 years away. Quote Link to comment Share on other sites More sharing options...
PB666 Posted February 12, 2018 Share Posted February 12, 2018 2 hours ago, sevenperforce said: Hydrogen is very fluffy. Also, the atmosphere is so low in water vapor that you're looking at thousands of cubic meters of air per liter of extracted water. I agree. Doug isn't quite right; specific impulse on the terminal stage is important, but other issues (like dry mass and TWR) are also important. That's why even a solid-fueled kick stage can beat hydrolox if the kick stage has a low enough dry mass (not that that's the case here; just saying). A high-thrust kerolox lifter makes mincemeat out of gravity drag on the ascent, saving lots of fuel for the orbital stage. And yes, the proof is in the eating. If SpaceX can deliver 12 tonnes to GTO for $95M, where is ULA's 8.9 tonnes for $150M or more? The Falcon family upper stage carries five times as much propellant as the Centaur. For anything other than very, very small payloads, it will pack more dV than the Centaur every time. A 450-second isp stage needs to burn 46% of its gross mass in order to get from LEO to GTO. A 345-second-isp stage needs to burn 55% of its gross mass in order to get from LEO to GTO. If I am a very knowledgeable customer, Just let them drop the craft at LEO-2/3rd GTO and use ION drive to get me to GTO and I will keep my payload and thumb my nose at the centaur. Quote Link to comment Share on other sites More sharing options...
DAL59 Posted February 12, 2018 Share Posted February 12, 2018 52 minutes ago, insert_name said: https://twitter.com/elonmusk/status/963092110994886656?s=20 Quote Link to comment Share on other sites More sharing options...
DAL59 Posted February 12, 2018 Share Posted February 12, 2018 Hmm... I know this isn't going to happen, but it would be very nice to to have a 50th anniversery moon landing. 50 years after Apollo 11, and we still only have up to 6 people in space. Sigh. Quote Link to comment Share on other sites More sharing options...
PB666 Posted February 13, 2018 Share Posted February 13, 2018 23 minutes ago, DAL59 said: Note that Musk was responding to a comment about the ULA Vulcan rocket, that's why I made the point. Its not that he likes hats, its he's very dubious about the progress of the Vulcan . . .So am I. Quote Link to comment Share on other sites More sharing options...
cubinator Posted February 13, 2018 Share Posted February 13, 2018 I now have music from T-1:00 to T+2:30 of Falcon Heavy. Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted February 13, 2018 Share Posted February 13, 2018 49 minutes ago, DAL59 said: Damn, that's some fierce shade. 31 minutes ago, DAL59 said: Hmm... I know this isn't going to happen, but it would be very nice to to have a 50th anniversery moon landing. 50 years after Apollo 11, and we still only have up to 6 people in space. Sigh. I've been working on doing this very thing in stock. Quote Link to comment Share on other sites More sharing options...
DAL59 Posted February 13, 2018 Share Posted February 13, 2018 1 hour ago, sevenperforce said: ome fierce shade. especially because he's wearing shades Quote Link to comment Share on other sites More sharing options...
tater Posted February 13, 2018 Share Posted February 13, 2018 Quote Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted February 13, 2018 Share Posted February 13, 2018 Quote Not enough ignition fluid to light the outer two engines after several three engine relights. Fix is pretty obvious. I wonder about that a bit. Given that this is rocket science, don’t they know like down to the gram how much TEA-TEB they’re going to need for x amount of relights, or is it a dynamic number that the engine computer has to constantly adjust during startup, making it unpredictable? Quote Link to comment Share on other sites More sharing options...
KSK Posted February 13, 2018 Share Posted February 13, 2018 8 hours ago, tater said: https://twitter.com/elonmusk/status/963103592881168384?ref_src=twcamp^share|twsrc^m5|twgr^email|twcon^7046|twterm^0 Ahh dagnabbit. Ninja'ed by @tater for the fun part of that tweet and by @magnemoe for the informative stuff. In my defence, time zones being what they are, it's pretty hard to get out of bed earlier than you folks in the morning. 7 hours ago, cubinator said: I now have music from T-1:00 to T+2:30 of Falcon Heavy. Awesome! Do you have a link? I've had a peek at your forum profile but couldn't find anything in your recent posting history. Quote Link to comment Share on other sites More sharing options...
magnemoe Posted February 13, 2018 Share Posted February 13, 2018 3 hours ago, CatastrophicFailure said: I wonder about that a bit. Given that this is rocket science, don’t they know like down to the gram how much TEA-TEB they’re going to need for x amount of relights, or is it a dynamic number that the engine computer has to constantly adjust during startup, making it unpredictable? Core went far faster than the normal first stages as in 10.000 Km/h as I saw, imagine it was an higher back pressure making engines harder to start. Quote Link to comment Share on other sites More sharing options...
cubinator Posted February 13, 2018 Share Posted February 13, 2018 5 hours ago, KSK said: Awesome! Do you have a link? I've had a peek at your forum profile but couldn't find anything in your recent posting history. Sorry, I'm not posting it until it's complete and polished. You can hear an early version of the build-up to launch here. Even that has changed some. Quote Link to comment Share on other sites More sharing options...
Val Posted February 13, 2018 Share Posted February 13, 2018 Moved a couple pages worth of posts (again ) to: Quote Link to comment Share on other sites More sharing options...
PB666 Posted February 14, 2018 Share Posted February 14, 2018 They can't be serious. Quote Link to comment Share on other sites More sharing options...
tater Posted February 14, 2018 Share Posted February 14, 2018 Quote Link to comment Share on other sites More sharing options...
NSEP Posted February 14, 2018 Share Posted February 14, 2018 6 minutes ago, tater said: Cool, thx Ajit. Quote Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted February 14, 2018 Share Posted February 14, 2018 17 minutes ago, NSEP said: Cool, thx Ajit. Never thought I would ever hear that spoken on the Internet. Cool development, tho. Quote Link to comment Share on other sites More sharing options...
NSEP Posted February 14, 2018 Share Posted February 14, 2018 When is Block 5 going to launch? Nobody knows? Quote Link to comment Share on other sites More sharing options...
RCgothic Posted February 14, 2018 Share Posted February 14, 2018 April 15th, Iridium 51-55 according to Wikipedia. Date may vary. Quote Link to comment Share on other sites More sharing options...
DAL59 Posted February 14, 2018 Share Posted February 14, 2018 1 hour ago, tater said: Starlink will be the end of all telecommuniation companies, if what Musk has said is true. Musk also probably is for NN, so this is good. However, I'm still duboius on how a phone could recieve enough bandwidth from a satelite. Quote Link to comment Share on other sites More sharing options...
magnemoe Posted February 14, 2018 Share Posted February 14, 2018 2 minutes ago, DAL59 said: Starlink will be the end of all telecommuniation companies, if what Musk has said is true. Musk also probably is for NN, so this is good. However, I'm still duboius on how a phone could recieve enough bandwidth from a satelite. SpaceX system will not work against phones, you would need an receiver more like an large wireless router. it will however work well against moving targets like cars or even planes. Even iridium phones are pretty bulky, for something like modern smart phones you probably need BFR and even then probably an way to print the antenna in orbit. Now the interesting part is that bandwidth is pretty shared so who more remote you are who higher bandwidth as few other uses it. Opposite of standard broadband Quote Link to comment Share on other sites More sharing options...
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