Wjolcz Posted May 13, 2017 Share Posted May 13, 2017 Sooo... No landing next time? Quote Link to comment Share on other sites More sharing options...
tater Posted May 13, 2017 Share Posted May 13, 2017 2 hours ago, Veeltch said: Sooo... No landing next time? You can see in the static burn image I posted it's expendable (no legs). Quote Link to comment Share on other sites More sharing options...
Wjolcz Posted May 13, 2017 Share Posted May 13, 2017 32 minutes ago, tater said: You can see in the static burn image I posted it's expendable (no legs). Quote Link to comment Share on other sites More sharing options...
tater Posted May 13, 2017 Share Posted May 13, 2017 It's funny, I used to watch all the launches I could back in the day, now the exciting bit is the landing. Quote Link to comment Share on other sites More sharing options...
Scotius Posted May 13, 2017 Share Posted May 13, 2017 Boring launches are best launches. It means everything is working as intended Thrill might be gone, but we all know here how much every fireball costs and how it hurts space exploration. So - here's for boring, 100 % succesfull routine Quote Link to comment Share on other sites More sharing options...
softweir Posted May 13, 2017 Share Posted May 13, 2017 The thrill may be gone, but there is still something very satisfying about a clean, successful job done in what is a very difficult and treacherous field of endeavour. I watch quite a lot of launches (rarely live, given limited times of day I can do so) for the success - not the excitement of thinking "will it succeed - or fail?!" Quote Link to comment Share on other sites More sharing options...
wumpus Posted May 13, 2017 Share Posted May 13, 2017 3 hours ago, Scotius said: Boring launches are best launches. It means everything is working as intended Thrill might be gone, but we all know here how much every fireball costs and how it hurts space exploration. So - here's for boring, 100 % succesfull routine Sooner or later I will trip up and say "have a nominal trip" to a non space nerd. Quote Link to comment Share on other sites More sharing options...
Mad Rocket Scientist Posted May 14, 2017 Share Posted May 14, 2017 (edited) This was recently posted on /r/spacex: https://www.twitch.tv/videos/139688943 (Tom Mueller interview/Skype call) Couple of SpaceX related highlights: They avoid space vendors Block 5 will have reusable TPS and better landing legs that can fold for transport Elon on Merlin engines: Why do they cost more than a model S when they weight 1/5 as much? SpaceX has forced other LPs to innovate, reuse. Raptor designed to 99% thermal efficiency 30% of F9 cost is upper stage Videos claiming that SpaceX faked landing are highest compliment (because they are claiming that what you are doing is impossible) >4000psi combustion chamber pressure Methane is much cheaper than kerosene 1000t of propellant needs to be manufactured on Mars over 2 years to get home Elon wanted 12h F9 turnaround, settled for 24h Electric prop for sats SpaceX is looking at nuclear thermal, prohibitively expensive for SpaceX to develop due to environmental laws, if NASA every works on it SpaceX would "jump in" Raptor is 3.5, 3.6 O/F ratio ITS could do jupiter direct with about 20t payload, no people without depots SpaceX is enabling "killer space apps" Working for Elon Musk is "pretty trippy" "different every day" "extremely demanding" tends to take the harder way Merlin uses "phase shutoff" Mueller advised Elon against it (removes many valves, some computers, harder R&D with many RUDs on test stands) SpaceX is following NASA planetary protection protocols, initially He also describes a rocket engine as "Throwing 800lbs of bricks at mach 10 every second" Transcript here: Edited May 14, 2017 by Mad Rocket Scientist Quote Link to comment Share on other sites More sharing options...
kerbiloid Posted May 14, 2017 Share Posted May 14, 2017 3 hours ago, Mad Rocket Scientist said: Raptor designed to 99% thermal efficiency SpaceX: Redesigning the thermodynamics. 3 hours ago, Mad Rocket Scientist said: Methane is much cheaper than kerosene Wasn't kerosene declared as "fuel costs almost nothing compared to a rocket"? 3 hours ago, Mad Rocket Scientist said: 1000t of propellant needs to be manufactured on Mars over 2 years to get home They would start with a greenhouse. Anyway more realistic than a return. 3 hours ago, Mad Rocket Scientist said: SpaceX is looking at nuclear thermal To drop the thermal efficiency from 99% back to 50? No way. 3 hours ago, Mad Rocket Scientist said: SpaceX is enabling "killer space apps" 12000 sats occupying all near-Earth space. Nobody could just have a place to launch one more. Quote Link to comment Share on other sites More sharing options...
Scotius Posted May 14, 2017 Share Posted May 14, 2017 Sooo... SpaceX is interested in nuclear engines. I wondered when it will pop up It does make a lot of sense in context of ITS. Less thrust than a bunch of LFO engined clustered at the tail, but more efficiency, less hassle with fuel ( you only need to take methane along, skipping on the troublesome cryo'ed oxygen). And if you manage to develop dual-mode engine you will get power out of it - which would be handy during long - range missions beyond Mars orbit. Well, in perfect world it would be the moment when NASA would step forward, be pioneers again and finally finish developing this darned thing. Alas, it's not going to happen. *le sigh* Quote Link to comment Share on other sites More sharing options...
Vinhero100 Posted May 14, 2017 Share Posted May 14, 2017 I like Elon Musk's Idea, but I'm not sure why he's not worried about radiation. but.... (fun fact, *mulch* in real life can block some radiation- I think) Quote Link to comment Share on other sites More sharing options...
magnemoe Posted May 14, 2017 Share Posted May 14, 2017 4 hours ago, Scotius said: Sooo... SpaceX is interested in nuclear engines. I wondered when it will pop up It does make a lot of sense in context of ITS. Less thrust than a bunch of LFO engined clustered at the tail, but more efficiency, less hassle with fuel ( you only need to take methane along, skipping on the troublesome cryo'ed oxygen). And if you manage to develop dual-mode engine you will get power out of it - which would be handy during long - range missions beyond Mars orbit. Well, in perfect world it would be the moment when NASA would step forward, be pioneers again and finally finish developing this darned thing. Alas, it's not going to happen. *le sigh* Methane is just as cryogenic as oxygen. Using nuclear thermal or other space engines also changes the setup, it would probably be easier to design an in space only ship for the earth - mars run. Yes you could also go nuts or the tug route as many of us do in ksp. Tug accelerate payload to escape speed then brakes and return to low orbit. This became harder with the 1.x simply as we don't have customization heat shields. Quote Link to comment Share on other sites More sharing options...
tater Posted May 14, 2017 Share Posted May 14, 2017 (edited) Anyone serious is interested in nuclear engines or space reactors, the only people against them are Luddites. Edited May 14, 2017 by tater Quote Link to comment Share on other sites More sharing options...
wumpus Posted May 14, 2017 Share Posted May 14, 2017 10 hours ago, kerbiloid said: SpaceX: Redesigning the thermodynamics. Carnot? Any relation to Bug's aluminum carrot? Wasn't kerosene declared as "fuel costs almost nothing compared to a rocket"? If you are buying into the "100 launches per rocket" fantasy, costs of fuel might break out of the noise. They would start with a greenhouse. Anyway more realistic than a return. Ignoring the return would be a PR disaster. I don't think it is really an option. To drop the thermal efficiency from 99% back to 50? No way. Troll harder. Or maybe the others were just too easy. 12000 sats occupying all near-Earth space. Nobody could just have a place to launch one more. Also close the patent office. Everything has already been invented. Comments in red because I couldn't figure out how to break up the quote block. Started out well, but the snark fell into trolling toward the end (when you ran out of "marketing/PR" to puncture). Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted May 14, 2017 Share Posted May 14, 2017 3 hours ago, magnemoe said: Methane is just as cryogenic as oxygen. Using nuclear thermal or other space engines also changes the setup, it would probably be easier to design an in space only ship for the earth - mars run. Yes you could also go nuts or the tug route as many of us do in ksp. Tug accelerate payload to escape speed then brakes and return to low orbit. This became harder with the 1.x simply as we don't have customization heat shields. For certain trajectories, the tug can take a free-return trajectory back and then aerobrake/aerocapture. Quote Link to comment Share on other sites More sharing options...
kerbiloid Posted May 14, 2017 Share Posted May 14, 2017 16 minutes ago, wumpus said: Carnot? Any relation to Bug's aluminum carrot? Heat cycle with 99% thermodynamics efficiency? Really? 18 minutes ago, wumpus said: If you are buying into the "100 launches per rocket" fantasy, costs of fuel might break out of the noise Breaking the tested kerolox design to implement totally new fuel? When a year ago fuel price didn't matter? 20 minutes ago, wumpus said: Ignoring the return would be a PR disaster. I don't think it is really an option. I mean, to produce and keep 1000 t of cryomethane they would first colonize Mars. 22 minutes ago, wumpus said: Troll harder. Or maybe the others were just too easy. No troll, Nuke plants efficiency is just ~30%. Too puny if compared with declared 99% on chemicals. Quote Link to comment Share on other sites More sharing options...
magnemoe Posted May 14, 2017 Share Posted May 14, 2017 10 hours ago, kerbiloid said: SpaceX: Redesigning the thermodynamics. Wasn't kerosene declared as "fuel costs almost nothing compared to a rocket"? They would start with a greenhouse. Anyway more realistic than a return. To drop the thermal efficiency from 99% back to 50? No way. 12000 sats occupying all near-Earth space. Nobody could just have a place to launch one more. RP1 is cheap compared to the rocket. However I guess its very expensive compared to standard kerosene. As he said and who is probably correct is that the space industry has an very high price level. Then you liquefy natural gas its very simple to get pure methane and this is done in large scale today. You could get pretty cheap RP1 you did an long term deal with an refinery and they made it as part of the refinery process. You have to return, other options is way more technical complex and have moral / pr issues who makes the no go for dictatorships. I did not get the thermal efficient part either, sounds like an random out of content quote from an bullet list. Its room for a lot of satellites. Quote Link to comment Share on other sites More sharing options...
kerbiloid Posted May 14, 2017 Share Posted May 14, 2017 (edited) 15 minutes ago, magnemoe said: Then you liquefy natural gas its very simple to get pure methane Gas refinery just doesn't need to deal with heavy fluids. But it's not just liquefy, it has same stages of separation and purification as oil refinery. And here they speak not about gas for civil needs, but about rocket quality fuel. And this fuel requires large insulated tanks rather than kerosene, so yet nobody was interested in it enough much. Anyway, trying to imagine 1000 t plant and storage on Mars... Don't forget: you can't just scale down a terrestrial refinery and build just in a Martian barn. Size matters. So, very probably the plant will weight much more than 1000 t of product (rocket-quality product). Edited May 14, 2017 by kerbiloid Quote Link to comment Share on other sites More sharing options...
tater Posted May 14, 2017 Share Posted May 14, 2017 The solar required to refuel is insane. They need a reactor. Quote Link to comment Share on other sites More sharing options...
Mad Rocket Scientist Posted May 14, 2017 Share Posted May 14, 2017 11 hours ago, kerbiloid said: [...] Wasn't kerosene declared as "fuel costs almost nothing compared to a rocket"? [...] Nothing compared to a rocket, but RP-1 costs 8$/gallon, while jet fuel costs 2$/gallon and methane is even cheaper. Quote Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted May 14, 2017 Share Posted May 14, 2017 As I recall, MEthane's biggest advantage is that it's clean burning, vs kerosene that leaves deposits. Important for quick-turnaround reusability. That it's also cheaper is just an incidental plus. Quote Link to comment Share on other sites More sharing options...
Elthy Posted May 14, 2017 Share Posted May 14, 2017 They want to get the costs down enough for the fuelcost to matter... BTW: The nice thing about SpaceX approach is that they plan to do without nuclear engines, not having to deal with radiation (especialy when landed) helps a lot with lowering the costs. Quote Link to comment Share on other sites More sharing options...
monophonic Posted May 14, 2017 Share Posted May 14, 2017 24 minutes ago, CatastrophicFailure said: As I recall, MEthane's biggest advantage is that it's clean burning, vs kerosene that leaves deposits. Important for quick-turnaround reusability. That it's also cheaper is just an incidental plus. Methane also has four hydrogens per carbon compared to a bit over two for kerosene. (Exact value depends on the average chain length as well as whether any cyclic or unsaturated hydrocarbons are present.) This gives methalox a better ISP than kerolox while still avoiding the nuisance that is liquid hydrogen storage. (Although hydrolox ISP will still reign supreme in chemical rocketry.) Also IIRC Blue Origin is also developing methalox, so the combination obviously has some merit over more traditional choices. IMO price is unlikely to be the main driver, although any savings are always nice as far as a business thinks. Quote Link to comment Share on other sites More sharing options...
RedKraken Posted May 14, 2017 Share Posted May 14, 2017 16 hours ago, Mad Rocket Scientist said: Tom Mueller interview/Skype call This is the guy i've been waiting to hear from. The rockstar of rocket engine design. Tom talking about the merlin engine. Glushko did FFSC with the RD-270 in the 1960s, test-fired but it never flew. Tom Mueller might be the first guy on the planet to see his FFSC rocket engine fly. Not only fly...but fly to Mars. (I hope we get to meet some of the other guys on the raptor engine team.) 16 hours ago, Mad Rocket Scientist said: 1000t of propellant needs to be manufactured on Mars over 2 years to get home ITS can get home from mars on a half-tank. Surprising how many dont get it. About 7000m/s for 25t cargo on board. 16 hours ago, Mad Rocket Scientist said: Raptor is 3.5, 3.6 O/F ratio Was using 3.8 (bulk density 0.90kg/L) in my calcs. Methane bulk density @ O/F 3.6 is 0.89kg/L. I wonder when he will post the twr, or will elon pull rank. Quote Link to comment Share on other sites More sharing options...
Green Baron Posted May 14, 2017 Share Posted May 14, 2017 (edited) 29 minutes ago, RedKraken said: ITS can get home from mars on a half-tank. Surprising how many dont get it. About 7000m/s for 25t cargo on board. aehm ... the ITS doesn't exist yet ... as far as i read it is unclear whether there is a full sized raptor ... no dry mass, no isp (*), no dV. And one will have to wait for a somewhat convenient phase angle if one day someone should wish to return home again ... Just saying :-) Edit (*) except raw figures from a presentation Edited May 14, 2017 by Green Baron Quote Link to comment Share on other sites More sharing options...
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