CatastrophicFailure Posted May 2, 2021 Share Posted May 2, 2021 On 5/1/2021 at 8:17 PM, YNM said: Pretty sure you can reduce the amount of fuel only down to the amount you need. Otherwise they wouldn't have been able to de-orbit (venting fuel is really just opening the prop valves AFAIK) or had to do away with active attitude control of the capsule for re-entry. (Soyuz has had to do quite a number of the latter.) Expand Interesting, just heard on the livestream they actually do do a “propellant waste” burn to get rid of unneeded fuel. On 5/2/2021 at 3:28 AM, kerbiloid said: I guess, Boeing knows better than me. Expand Their track record isn’t exactly the best right now... Quote Link to comment Share on other sites More sharing options...
kerbiloid Posted May 2, 2021 Share Posted May 2, 2021 On 5/2/2021 at 6:05 AM, CatastrophicFailure said: Their track record isn’t exactly the best right now... Expand B-737 still flies much better than Starship. Quote Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted May 2, 2021 Share Posted May 2, 2021 On 5/2/2021 at 6:36 AM, kerbiloid said: B-737 still flies much better than Starship. Expand Not the MAX. Quote Link to comment Share on other sites More sharing options...
kerbiloid Posted May 2, 2021 Share Posted May 2, 2021 On 5/2/2021 at 7:27 AM, CatastrophicFailure said: Not the MAX. Expand Even the MAX. It has performed more than zero successful landing. Quote Link to comment Share on other sites More sharing options...
YNM Posted May 2, 2021 Share Posted May 2, 2021 On 5/2/2021 at 6:36 AM, kerbiloid said: B-737 still flies much better than Starship. Expand And Starliner worse than Dragon 2. Quote Link to comment Share on other sites More sharing options...
tater Posted May 2, 2021 Author Share Posted May 2, 2021 On 5/2/2021 at 7:58 AM, kerbiloid said: Even the MAX. It has performed more than zero successful landing. Expand Reveal hidden contents Spoilered cause it's off topic, but it keeps coming up anyway, lol. Starship will continue dev as an expendable LV until it starts working. It's entirely reasonable to not treat SS as existing as a LV choice—because it is not flying yet (flying defined as servicing orbital customers). That said, it will very likely work as an expendable vehicle (that part is pretty easy) with little iteration. Booster recovery... depends on if they put legs on it or not. With legs, recovery is trivial for SpaceX, it's a solved problem. Catching it? LOL, who knows. Orbital recovery? This is the long pole, and I fully expect a bunch of spectacular failures. Will it ever stop failing and work? I honestly don't know, but I do know that if it does work—all other launch vehicles are obsolete from that point forward. How does this relate to THIS thread? I would argue that it's rational to assign the probability of SS/SH success at some level below 100%, in fact as much below 100% as anyone thinks with good reasons. You might think it has a 10% chance of success, for example, and that another method (winged like Shuttle/Buran) might be 90% likely to succeed. That said, if they hit that 10%, any other vehicles in dev right now are pretty much useless except for use by governments throwing a bone at their launch services. How much money is spent on similar dev for fully reusable LVs will obviously be a function of how likely they think SS success is—but I think anyone being rational should assign that probability >0, even if they give it a low value. Quote Link to comment Share on other sites More sharing options...
sh1pman Posted May 2, 2021 Share Posted May 2, 2021 On 5/2/2021 at 3:09 PM, tater said: How does this relate to THIS thread? I would argue that it's rational to assign the probability of SS/SH success at some level below 100%, in fact as much below 100% as anyone thinks with good reasons. You might think it has a 10% chance of success, for example, and that another method (winged like Shuttle/Buran) might be 90% likely to succeed. That said, if they hit that 10%, any other vehicles in dev right now are pretty much useless except for use by governments throwing a bone at their launch services. Expand There aren't any fundamental obstacles for SS to work. Launch - done by SpaceX F9. 1st stage recovery - done by SpaceX F9. SS orbit and deorbit burns - trivial at this point, Raptors are reliable enough. Chomper fairing - concept proven by Shuttle cargo bay and Crew Dragon nose cone. Reentry of a large orbiter - done by the Shuttle, attitude control by SS flaps also shown by SpaceX. Flip maneuver and landing - done by SN10. Some issues with header tanks left to iron out. I'm sure they'll fix them before the end of this year, given the latest NASA endorsement. The best time for other countries to start working on a fully reusable orbital rocket was 5 years ago. The second best time is right now. Quote Link to comment Share on other sites More sharing options...
tater Posted May 2, 2021 Author Share Posted May 2, 2021 On 5/2/2021 at 3:49 PM, sh1pman said: The best time for other countries to start working on a fully reusable orbital rocket was 5 years ago. The second best time is right now. Expand This I think is true. One thing perhaps relevant to this thread is that I don't think that any new concept needs to copy SpaceX (I'm looking at you, China, lol). I think that novel concepts could work. I love the old flyback booster ideas I have seen for Russian vehicles, I'd really like to see some of those actually done. What do people think of ideas like MAKS? Was it canceled for budget reasons, or technical issues? Quote Link to comment Share on other sites More sharing options...
kerbiloid Posted May 2, 2021 Share Posted May 2, 2021 (edited) On 5/2/2021 at 3:09 PM, tater said: How does this relate to THIS thread? Expand It doesn't. I honestly have no idea why somebody started insisting that Starship is a proper way to reorbit the ROSS. Obviously, is Starship is good or not, it will never have any relation to the subject. I just posted a brief description of the planned orbital station. Actually, all posts after that long read are offtopic and would be removed. Edited May 2, 2021 by kerbiloid Quote Link to comment Share on other sites More sharing options...
sh1pman Posted May 2, 2021 Share Posted May 2, 2021 On 5/2/2021 at 3:56 PM, tater said: I think that novel concepts could work. I love the old flyback booster ideas I have seen for Russian vehicles, I'd really like to see some of those actually done. Expand Something like Energia-2 with flyback boosters and a winged second stage could work for Roscosmos. They had the right idea 30 years ago. Now it looks like they don't. Reveal hidden contents Quote Link to comment Share on other sites More sharing options...
kerbiloid Posted May 2, 2021 Share Posted May 2, 2021 (edited) (ninja'd) Edited May 2, 2021 by kerbiloid Quote Link to comment Share on other sites More sharing options...
tater Posted May 2, 2021 Author Share Posted May 2, 2021 On 5/2/2021 at 4:04 PM, sh1pman said: Something like Energia-2 with flyback boosters and a winged second stage could work for Roscosmos. They had the right idea 30 years ago. Now it looks like they don't. Expand That thing is awesome. Quote Link to comment Share on other sites More sharing options...
sh1pman Posted May 2, 2021 Share Posted May 2, 2021 On 5/2/2021 at 3:56 PM, tater said: What do people think of ideas like MAKS? Was it canceled for budget reasons, or technical issues? Expand Mostly economic reasons, but also lack of political will and the reliance on a Ukrainian An-225 carrier airplane, which is now unavailable for obvious reasons. Reveal hidden contents Quote Link to comment Share on other sites More sharing options...
DDE Posted May 6, 2021 Share Posted May 6, 2021 In honor of today's Starship hop Quote Link to comment Share on other sites More sharing options...
RCgothic Posted May 6, 2021 Share Posted May 6, 2021 Quote Link to comment Share on other sites More sharing options...
SOXBLOX Posted May 6, 2021 Share Posted May 6, 2021 At which point it will be pushed back again, and so on, ad infinitum... Quote Link to comment Share on other sites More sharing options...
DDE Posted May 6, 2021 Share Posted May 6, 2021 On 5/6/2021 at 8:05 PM, SOXBLOX said: At which point it will be pushed back again, and so on, ad infinitum... Expand Word is the entire sprawling Rostech has serious cash flow problems - companies are being pressured to deliver despite not getting paid on time. That said, Soyuz-6 is a semi-private enterprise that plays sevond fiddle to Soyuz-5, which requires the full-size RD-171MV. Quote Link to comment Share on other sites More sharing options...
DDE Posted May 9, 2021 Share Posted May 9, 2021 The absolute trash heap that is Yandex.Zen just spat out a very interesting tidbit at me. Разработки самого высокого полёта (sovsibir.ru) The Institute of Catalysis of the Siberian Department of the academy of sciences is working on restoring the production of ortho-hydrogen to para-hydrogen conversion catalysts. Us Ignition! fans know what it means: Quote Hydrogen is a super-cryogenic. Its boiling point of 21 K is lower than that of any other substance in the universe except helium. (That of oxygen is 90 K.) Which means that problems of thermal insulation are infinitely more difficult than with oxygen. And there is another difficulty, which is unique to hydrogen. Quantum mechanics had predicted that the hydrogen molecule, H2, should appear in two forms: ortho, with the nucleii of the two atoms spinning in the same direction (parallel), and para, with the two nucleii spinning in opposite directions (antiparallel). It further predicted that at room temperature or above, three-quarters of the molecules in a mass of hydrogen should appear in the ortho form and a quarter in the para, and that at its boiling point almost all of them should appear in the para state. But for years nobody observed this phenomenon. (The two forms should be distinguishable by their thermal conductivity.) Then, in 1927, D. M. Dennison pointed out, in the Proceedings of the Royal Society, that the transition from the ortho to the para state might be a slow process, taking, perhaps, several days, and that if the investigators waited a while before making their measurements, they might get some interesting results. Urey, Brickwedde and others in this country, as well as Clusius and Hiller in Germany looked into the question exhaustively between 1929 and 1937, and the results were indeed interesting, and when the propellant community got around to looking them up, disconcerting. The transition was slow, and took several days at 21 K. But that didn't matter to the rocket man who merely wanted to burn the stuff. What did matter was that each mole of hydrogen (2 grams) which changed from the ortho to the para state gave off 337 calories of heat in the process. And since it takes only 219 calories to vaporize one mole of hydrogen, you were in real trouble. For if you liquefied a mass of hydrogen, getting a liquid that was still almost three quarters orthohydrogen, the heat of the subsequent transition of that to para-hydrogen was enough to change the whole lot right back to the gaseous state. All without the help of any heat leaking in from the outside. The answer to the problem was obvious — find a catalyst that will speed up the transition, so that the evolved heat can be disposed of during the cooling and liquefaction process and won't appear later to give you trouble; and through the 50's, several men were looking for such a thing. P. L. Barrick, working at the University of Colorado and at the Bureau of Standards at Boulder, Colorado, came up with the first one to be used on a large scale —hydrated ferric oxide. Since then several other catalytic materials have been found —palladium-silver alloys, ruthenium, and what not, several of them much more efficient than the ferric oxide —and the ortho-para problem can be filed and forgotten. By 1961 liquid hydrogen was a commercial product, with Linde, Air Products, and several other organizations ready to sell you any amount you wanted, and to ship it to you in tank car lots. (The design of those tank cars, by the way, is quite something. Entirely new kinds of insulation had to be invented to make them possible.) Expand Quote Link to comment Share on other sites More sharing options...
sh1pman Posted May 10, 2021 Share Posted May 10, 2021 On 5/9/2021 at 6:54 PM, DDE said: Разработки самого высокого полёта (sovsibir.ru) Expand Can expect hydrogen rockets? Quote Link to comment Share on other sites More sharing options...
kerbiloid Posted May 10, 2021 Share Posted May 10, 2021 On 5/10/2021 at 2:51 PM, sh1pman said: Can expect hydrogen rockets? Expand Yes, metallic. Quote Link to comment Share on other sites More sharing options...
kerbiloid Posted May 13, 2021 Share Posted May 13, 2021 (edited) https://translate.google.com/translate?hl=&sl=ru&tl=en&u=https://www.interfax.ru/russia/765829 The main and backup actresses and directors are selected for the planned filiming of the first real space movie. Main staff: Yulia Peresild and Klim Shipenko https://translate.google.com/translate?hl=&sl=ru&tl=en&u=https://www.kino-teatr.ru/kino/acter/w/ros/3298/works/ Alyona Mordovina and Alexei Dudin https://translate.google.com/translate?hl=&sl=ru&tl=en&u=https%3A%2F%2Fwww.kino-teatr.ru%2Fkino%2Facter%2Fw%2Fros%2F434628%2Fworks%2F&sandbox=1 One more actress from the casting, Galina Kairova, a trained pilot graduated from Krasny Kut flight school, got an offer to continue this professionally in the cosmonaut team. *** Much better than Tom Cruise, much better. Indeed. *** https://translate.google.com/translate?hl=&sl=ru&tl=en&u=https://www.interfax.ru/world/765818 https://techcrunch.com/2021/05/13/spacexs-inaugural-moon-tour-private-astronaut-is-heading-to-the-international-space-station-first/ Two Japanese tourists will fly to the ISS in December on Soyuz: https://en.wikipedia.org/wiki/Yusaku_Maezawa and his assistant Yozo Hirano. Edited May 13, 2021 by kerbiloid Quote Link to comment Share on other sites More sharing options...
tater Posted May 13, 2021 Author Share Posted May 13, 2021 Quote Link to comment Share on other sites More sharing options...
insert_name Posted May 13, 2021 Share Posted May 13, 2021 Isnt that the DearMoon guy, wonder if he got tired of waiting, or if this is just a rehearsal for the moon mission Quote Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted May 13, 2021 Share Posted May 13, 2021 On 5/13/2021 at 7:04 PM, insert_name said: Isnt that the DearMoon guy, wonder if he got tired of waiting, or if this is just a rehearsal for the moon mission Expand Prolly just wants to have all the boxes checked for the Rich Guy Spaceflight triple crown. Quote Link to comment Share on other sites More sharing options...
SunlitZelkova Posted May 13, 2021 Share Posted May 13, 2021 On 5/13/2021 at 7:04 PM, insert_name said: Isnt that the DearMoon guy, wonder if he got tired of waiting, or if this is just a rehearsal for the moon mission Expand The way he tweeted about it makes it just look like "another flight" as opposed to having some purpose or being in relation to DearMoon some how. Why go to space once when you can go twice? Quote Link to comment Share on other sites More sharing options...
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