Starship 12.5km launch - Page 1
Forum section: electronics / general

author: wraper
author_rank: Unknown
timestamp: December 09, 2020, 10:41:56 pm
content: EDIT: watch at 1:47:00EDIT2: Just in case somebody doesn't know how large this thing is, it's 9m (30ft) wide and about 50m (160ft) tall.

author: wraper
author_rank: Unknown
timestamp: December 09, 2020, 10:44:28 pm
content: 1 minute left, will be spectacular in either way it ends up.

author: wraper
author_rank: Unknown
timestamp: December 09, 2020, 10:53:44 pm
content: Well, it almost worked. Successfully hit the target.

author: Gyro
author_rank: Super Contributor
timestamp: December 09, 2020, 11:04:33 pm
content: That was awesome!

author: rdl
author_rank: Super Contributor
timestamp: December 10, 2020, 05:29:37 am
content: It was incredible how close they came to a perfect test flight. It was so cool to see it floating down sideways all shiny in the sunlight. I hope they figure out the fuel pressure problem quickly and try again soon.

author: BravoV
author_rank: Super Contributor
timestamp: December 10, 2020, 07:15:09 am
content: Love to see how the big fat ass rocket while falling with horizontal position, and then suddenly turned into vertical, slowing the fall and approached the land.Not a rocket scientist, as an avg. Joe, I considered that is a really close to success, and have really high confident on next trial.Wonder how much recorded data they've gathered.

author: sandalcandal
author_rank: Unknown
timestamp: December 10, 2020, 08:03:30 am
content: That was so cool

author: edy
author_rank: Super Contributor
timestamp: December 10, 2020, 07:11:51 pm
content: It was definitely spectacular to watch but now they have to go back and figure out why this thing either miscalculated its speed of approach on landing or perhaps didn't have enough thrust to carry out the instructions it was intending. Was it a matter of sensory input, calculations/feedback/prediction, or lack of proper motor output?

author: wraper
author_rank: Unknown
timestamp: December 10, 2020, 07:17:09 pm
content: Quote from: edy on December 10, 2020, 07:11:51 pmIt was answered within minutes after crash by Elon on Twitter. There was too small pressure in secondary tank used for landing. Thus only one engine kept somewhat working with barely any thrust. It's not like maneuver was miscalculated.

author: Gyro
author_rank: Super Contributor
timestamp: December 10, 2020, 10:33:32 pm
content: I love Manley's description of "engine rich exhaust". That's even better than 'RUD'.

author: Brumby
author_rank: Unknown
timestamp: December 11, 2020, 12:57:06 am
content: Quote from: Gyro on December 10, 2020, 10:33:32 pmMade me smile too.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 06:21:10 am
content: Please, explain what makes SpaceX so happy? With modern tools, they try to repeat what was done many years ago with primitive tools. Yes, well done, it's good that there is work for engineers, but this is the invention of the wheel.I bought a tube from an old soviet scope and want to make it a three-beam high-voltage low-freq scope with isolated inputs - will you be happy for me?

author: BravoV
author_rank: Super Contributor
timestamp: December 12, 2020, 07:03:19 am
content: Quote from: S. Petrukhin on December 12, 2020, 06:21:10 amWell, at least for me, SpaceX did the inverted what Russia had done, which is turned the rocket falling in horizontal position, into vertical position while slowing down to be landed, while Russia as below example on the supersonic missile launch, that turned the rocket vertically into horizontal and leaving the land with acceleration.Ok, similar ... but ... nahh .. forget it.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 07:16:56 am
content: Quote from: BravoV on December 12, 2020, 07:03:19 amI didn't really understand what it was about...In the video, the rocket is fired vertically because it is universal and very fast - you do not need to slowly turn around before launching, it can turn itself instantly. In addition, the main engine starts after the rocket is ejected by an ejecting projectile so that it does not blow anyone away on the ground. This has long been used in the missiles of many countries.And vertical jet landing has been used many times by NASA to land on the Moon. Soviet lunar rovers also had a vertical landing.This is a common thing, and all space countries already have these technologies.

author: BravoV
author_rank: Super Contributor
timestamp: December 12, 2020, 07:27:48 am
content: Quote from: S. Petrukhin on December 12, 2020, 07:16:56 amCmiiw, I thought these kind launch style is to ensure the missile attitude is low, hence low radar footprint, either while cruising to the target or protecting the launch location.Traditional missile like ICBM or common ones, launched vertically, and do not need to turn horizontally so fast right ?Quote from: S. Petrukhin on December 12, 2020, 07:16:56 amMoon has no atmosphere (hence no side wind) and much lower gravity, so these alone are not a major factors on the difficulty/complexity ?

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 07:30:36 am
content: By the way, pay attention: the rocket turns around the center due to two steering engines at the edges. For some reason, SpaseX decided to rotate one engine around the nose, which I think is unwise. But I can be wrong, probably a fairly powerful main engine on the nose did not fit.And I also have an idea that rockets don't fly backwards, that the problems started earlier, when the skin fires were visible. And then it fell with the engine turned off very hot. And the red, then the green color of the flame, I think, from the fact that something melted and burned there.Besides, if I'm not mistaken, Ilon understands Russian a little, probably he watched one wonderful Soviet movie "KIN-DZA-DZA" with such a device "Pepelats", but did not understand that this is a comedy...

author: Vovk_Z
author_rank: Super Contributor
timestamp: December 12, 2020, 07:32:37 am
content: Quote from: S. Petrukhin on December 12, 2020, 06:21:10 amMany years ago the whole Soviet Union (or the USA), a very large country (almost the whole continent) worked together to make a rocket. It cost too much for the Soviet people. Now it is done by a quite smallprivatecompany.P.S. And jealousy is a bad thing.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 07:38:19 am
content: I recommend watching a funny сomedy with a great philosophy (have subtitles).

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 07:53:33 am
content: Quote from: Vovk_Z on December 12, 2020, 07:32:37 amBut this private company is located in a country that has long mastered space. Do you think this private company doesn't have the technology and expertise? After all, NASA is very seriously involved, obviously investing a lot of money.Where do you see jealousy? I am glad that he has a lot of money and spends it on the development of technology, that engineers have a good job. But somehow the result reminds me Arduino...And I still can't understand why american missiles need russian engines. Where did the american ones go?

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 08:08:50 am
content: Quote from: BravoV on December 12, 2020, 07:27:48 amYes, agree. This rocket is flying low. But I was talking about a more convenient start. Intercontinental missiles have a different task - they rather need to escape up into orbit, where they can no longer be caught.But in any case, it is always more profitable to turn around the center than around the edge.Landing on the Moon is just less energy-intensive, algorithmically it differs from landing on Earth only in coefficients.And, if you remember, the Moon landings were performed manually by humans with very limited fuel resources.The American guys did it successfully several times (I don't remember how many - 9?). Almost visually!Are modern positioning and computing tools afraid of the wind?So go ask Armstrong how to do it. He trained on the Earth and did it like everyone else.

author: wraper
author_rank: Unknown
timestamp: December 12, 2020, 10:00:04 am
content: Quote from: S. Petrukhin on December 12, 2020, 06:21:10 amReally? Please tell me who ever landed the rocket or even simply space capsule in this way. Not to say no one besides them landed orbital class rocket yet.QuoteStarship rotates by using main rocket engines. On the nose there are only comparably weak cold gas thrusters for rapidly correcting it's position.QuoteThey do and you apparently have no clue. Their Falcon 9/heavy boosters land with engines first just fine. Read the thread instead of baking baseless claims. Engines malfunctioned due to lack of pressure in fuel tank.QuoteIf it's so easy to land 15 story building falling down from space, why nobody else did this?

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 10:15:44 am
content: Quote from: wraper on December 12, 2020, 10:00:04 amCan you walk backwards? Why do you usually go to the store, but don't come back from it in reverse?Yes, the steps are landing. What's unusual about this? Is it necessary? Is it safe? Do you think that all space companies would not be able to make such a landing and then some unique discovery? A man who just threw batteries from a store into a car?It's a good show, I think. I'm not saying that it's bad, on the contrary - it's better than many other things. But I don't see any admiration.Maybe I'm wrong, don't worry - just my opinion.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 10:17:48 am
content: Quote from: wraper on December 12, 2020, 10:00:04 amWatch the movie I suggested.I think you understand Russian very well. Relax and smile.

author: wraper
author_rank: Unknown
timestamp: December 12, 2020, 10:18:42 am
content: Quote from: S. Petrukhin on December 12, 2020, 07:53:33 amThey received way less money from NASA and did a way better job than traditional space companies. And it was not a free money but money to do particular job for NASA. Starship is developed using their own money.QuoteAmerican missiles don't use Russian engines. Atlas V rocket does, because sometime in the past ULA decided its a good deal financially. If not US government support of their over expensive rockets, they would be bust. They barely ever launched any commercial loads. They are not competitive when Spacex is around.QuoteTheir Rockets are way more reliable than your non-arduino Proton. F9/Heavy version B5, did not have a single launch failure ever (45 launches so far).

author: BravoV
author_rank: Super Contributor
timestamp: December 12, 2020, 10:21:01 am
content: Quote from: wraper on December 12, 2020, 10:00:04 amI get it now, I guess we're all "mis-understood"what S. Petrukhin intents to say, that Rusia is so rich, that throwing away such big rocket stage (pic below) is no big deal, probably for Rusia its like wiping nose with tissue paper and throw it away.Right ?

author: wraper
author_rank: Unknown
timestamp: December 12, 2020, 10:28:03 am
content: Quote from: S. Petrukhin on December 12, 2020, 10:15:44 amDo you realize that they reused Falcon 9 boosters around 50 times? Instead of building a brand new booster each time. The most used booster launched/landed 7 times already.QuoteNobody ever done it. And almost everybody joked about them and told it's impossible till the end of 2015 when they finally succeeded. Включая вашего Дмитрия Батутовича. Now Rogozin boasts they will make their own rocket which lands. Флаг ему в руки и удачи.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 10:31:22 am
content: Quote from: BravoV on December 12, 2020, 10:21:01 amYou'll probably be surprised. But this big rocket is cheaper than the small Falcon, as far as I know. In addition, the wreckage is collected and recycling.By the way, the heavy Angara is being prepared for launch, already on the launch pad.However, you can't hear me... Everyone can plant steps, but for some obviously good reason, they don't. It is possible that the reason is actually not so weighty and will continue to develop in this direction. My opinion: the Shuttle was a much-much bigger breakthrough. It would be more reasonable to make a new rocket based on its principle. This is my opinion, I'm not a rocket science professional.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 10:48:21 am
content: Quote from: wraper on December 12, 2020, 10:28:03 amYou know, in Russia, thinking people are puzzled by Rogozin. During the Soviet Union, I was on a tour and met with cosmonaut Leonov. We all smelled the glove - it had the smell of space.And even then, it was talking about cooperation in space. I listened a lot of cosmonauts stories - no one is hostile to the Americans. Moreover, the Americans have largely saved our cosmonautics and are grateful to them for this. There was competition, and there was a military side, of course. But this is not the case now. And the mentioned Rogozin... I have friends who work in the Roscosmos - all of them dissatisfied with current management. Everyone says that people of Soviet training will leave and it will be very bad. Perhaps, for the Russian cosmonautics, modern leadership is a disaster.

author: Refrigerator
author_rank: Super Contributor
timestamp: December 12, 2020, 10:50:46 am
content: Quote from: S. Petrukhin on December 12, 2020, 10:31:22 amScrap is worth nothing compared to what it once was. Buy a 1000$ GPU, smash it and sell it for scrap, you won't get even 1 dollar back.Imagine with every trip you scrapped your car and bought a new one, instead of doing basic maintenance and using it again.SpaceX made reusable engines and this serves more than to just lower the cost but additionally boosts development because the engines can be examined after landanding and even more data can be collected.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 11:03:53 am
content: Quote from: Refrigerator on December 12, 2020, 10:50:46 amMaybe you can explain why others didn't? Don't you think you were smart enough? What reasons do you think prevented from landing earlier?I can assume that there is a question of money: make a new car for each trip, as you put it, much more profitable for interested people.But there were no people in the USSR who profited from space.Or, nevertheless, space is not a supermarket and it is more reliable and even cheaper to go there in a disposable car, oddly enough?I don't know the answer. But I'm sure any space agency could do it.

author: cgroen
author_rank: Unknown
timestamp: December 12, 2020, 12:14:36 pm
content: Quote from: S. Petrukhin on December 12, 2020, 10:31:22 amNo shit Sherlock, I almost got the impression that you actually were a "rocket science professional", thanks for clearing that upPS: You got a LOT of reading and studying to do.......

author: wraper
author_rank: Unknown
timestamp: December 12, 2020, 12:36:53 pm
content: Quote from: S. Petrukhin on December 12, 2020, 10:31:22 amYou'll be surprised, but launch on Falcon 9 even in fully expendable variant is cheaper than on Proton, nor it is small. And that's even after launch price on Proton was reduced multiple times by more than 30% in total already, and another 30% drop is expected, to be at least somewhat competitive. Since Falcon 9 appeared, commercial launches on Proton essentially ceased to exist. Not to say that Falcon 9 can launch larger and heavier payloads than Proton and is way more reliable. Also due to poor reliability, insurance cost for Proton launches is very high.

author: wraper
author_rank: Unknown
timestamp: December 12, 2020, 12:55:53 pm
content: Falcon 9:Payload to LEOExpendable: 22,800 kg (50,300 lb)Reusable: 15,600 kg (34,400 lb)Payload to GTOExpendable: 8,300 kg (18,300 lb)Reusable: 5,500 kg (12,100 lb)Proton-MPayload to LEO 23,000 kg (51,000 lb)Payload to GTO 6,300 kg (13,900 lb)Falcon 9 payload volume is about 2 times larger. There is Falcon heavy which is also reusable, so there is basically no need to launch F9 in expendable variant unless customer requires so.Falcon Heavy:Payload to LEO 63,800 kg (140,700 lb)Payload to GTO 26,700 kg (58,900 lb)

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 04:27:33 pm
content: Quote from: wraper on December 12, 2020, 12:55:53 pmI don't really understand why 22800 is 2 times more than 23000...I do not know what LEO is, GTO is the height of the orbit, probably?Proton is a very old rocket that has existed since the very beginning of space exploration. I do not know the exact reliability statistics and will not argue. I'm not even interested in it. I am interested in cosmonautics out of curiosity.But the launch of the Angara carrier is scheduled for december 14. It seems that this rocket is much more powerful than the Proton. I don't know if the Energia is still alive. I think Falson can retire old man Proton. The modern leadership of Russian space seems to be successfully destroying everything...

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 04:29:38 pm
content: If the Falcon is better than the Proton, why NASA still buying the Proton launch?Why still buy RD-180 from the middle of the last century?

author: wraper
author_rank: Unknown
timestamp: December 12, 2020, 04:40:36 pm
content: Quote from: S. Petrukhin on December 12, 2020, 04:29:38 pmI never heard NASA buying Proton launch, for what? Soyuz astronaut launches is a different thing and they are launching on Falcon 9/Crew Dragon since this year. AFAIK the last seat they booked on Soyuz launched in October, as Dragon just started to launch astronauts they needed redundancy. And Boeing CST-100 is not ready yet. I doubt they will ever launch any astronaut on Soyuz after a year, if at all, and especially once CST-100 is ready and they have a second option. BTW NASA pays almost 2 times less per astronaut seat on Dragon compared to Soyuz, and can take significant cargo as well. BTW they can launch up to 7 people on a single Dragon if they need, and it still will be way more spacious than on Soyuz.EDIT: BTW both Crew Dragon and F9 boosters will be reused for crewed launches as wellhttps://spacenews.com/nasa-to-allow-reuse-of-crew-dragon-spacecraft-and-boosters/

author: Mr. Scram
author_rank: Super Contributor
timestamp: December 12, 2020, 05:15:13 pm
content: Quote from: S. Petrukhin on December 12, 2020, 10:31:22 amThe point is derived from basic physics. Take a good look at the rocket equation and tell us what you see. To launch a small payload you need a big rocket. Now imagine a scenario where instead of throwing almost the entire rocket away you can recover and comparatively trivially rebuild and refuel it. It completely changes how much stuff you can launch at what cost and rate completely. It makes space flight much more mundane, which has been Musk's goal from the start.The Space Shuttle promised to do something similar, but was an utter failure in the sense of cost and turnaround. It was a woefully expensive and finicky spacecraft. It also should be noted that what SpaceX is doing has not been done before. Landing a small craft on the Moon isn't the same game as landing a huge craft through an atmosphere. The challenges involved are nowhere near similar and the maths involved are a recent development. We literally could not do this before.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 06:01:17 pm
content: I try to write in detail, but you don't read or I don't explain well... I will write briefly.I wish success to all who work in space and to all engineers in general.While Russian space is still needed. But there are concerns.I don't see complex tasks solved in SpaceX, normal work, repetition of the past, but a lot of shows.By the way, if I had my own rocket, I would be the first to fly into space.

author: wraper
author_rank: Unknown
timestamp: December 12, 2020, 06:08:17 pm
content: Quote from: S. Petrukhin on December 12, 2020, 06:01:17 pmWhen I read what you write about rockets, my first thought is you don't have any idea what you are talking about. Such as: Falcon 9 is a small rocket, NASA buys Proton launches, landing a rocket is easy, and so on. Simply

author: Monkeh
author_rank: Super Contributor
timestamp: December 12, 2020, 06:08:32 pm
content: Quote from: S. Petrukhin on December 12, 2020, 06:01:17 pmThen you're not looking. You're dismissing out of ignorance.

author: Mr. Scram
author_rank: Super Contributor
timestamp: December 12, 2020, 06:18:24 pm
content: Quote from: S. Petrukhin on December 12, 2020, 06:01:17 pmYou seem to reduce and simplify to the point of all detail being lost, to then claim two detailless things are the same. You've been explained in some detail why and how things are different and you choose to just repeat earlier statements, ignoring any input. People aren't going to go into more detail when even broad basics are ignored. Folks here seem to be making some effort to explain things and ignoring any and all of it is honestly a bit rude.Tl;dr when you put your fingers in your ears, all arguments sound the same.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: December 12, 2020, 07:04:05 pm
content: All I can do is congratulate the Americans on returning to their launch vehicles. I don't know why NASA hasn't done this for years.And I wish to myself that our launch vehicles were also good and useful.Guys, this is not a scientific forum on cosmonautics, I don't understand why I - a simple spectator of cosmonautics-have such complaints. I express my humble opinion, write some arguments, you don't read them, write your arguments.Why are you so aggressive? What do you have to do with these successes? Why do you so zealously defend the sacredness of the event?I'm tired of this unfriendly communication.

author: wraper
author_rank: Unknown
timestamp: December 12, 2020, 07:53:44 pm
content: Quote from: S. Petrukhin on December 12, 2020, 07:04:05 pmBecause you mostly wrote arguments which are completely false. And diminish landing of what will be a truly reusable spacecraft with 100 tonne carrying capacity to anywhere in the Solar system, as if it was some reiteration of old technology. Also it's powered by rocket engines made by themselves. About engine, nobody ever before made any of this: 1. full-flow staged combustion engine which actually worked and left Earth surface, 2. operates on methane, 3. >300 atmosphere chamber pressure.

author: Mr. Scram
author_rank: Super Contributor
timestamp: December 12, 2020, 08:04:12 pm
content: Quote from: S. Petrukhin on December 12, 2020, 07:04:05 pmWho is being aggressive? People are trying to be helpful, but are unfortunately ignored. People not only read and understand your comments, but also explain why your comments may represent an overly simplistic view. People are only disappointed that you don't seem to want to read, understand or address any of the points that were made. That's got nothing to do with any event, but simply with disappointment regarding behaviour and common courtesy.

author: olkipukki
author_rank: Frequent Contributor
timestamp: December 12, 2020, 08:21:31 pm
content: Quote from: S. Petrukhin on December 12, 2020, 11:03:53 amIs it came from the same proverb list that famous "There is no sex in the USSR"?

author: wraper
author_rank: Unknown
timestamp: December 12, 2020, 08:28:01 pm
content: Quote from: olkipukki on December 12, 2020, 08:21:31 pmAlmost everyone is oblivious that the complete phrase was "There is no sex in the USSR... on TV". Poor woman who became a joke with no fault of her.

author: wraper
author_rank: Unknown
timestamp: December 12, 2020, 08:37:02 pm
content: Quote from: S. Petrukhin on December 12, 2020, 04:27:33 pmDo you not understand that volume != mass?https://en.wikipedia.org/wiki/Geostationary_transfer_orbithttps://en.wikipedia.org/wiki/Low_Earth_orbitQuoteAnd that's why Russian space industry sucks. The only new thing that was made is Angara that does not have anything truly innovative, nor makes any economic sense as it's more expensive. An old horse beaten to death is still used because of that.QuoteIt sucks. Both in USSR and more modern times. IIRC about 1 in 10 Proton launces resulted in failures. Was especially bad in 2010-2014. Do you not remember fiasco with 3 out of 6 angular velocity sensors mounted upside down?

author: jogri
author_rank: Frequent Contributor
timestamp: December 12, 2020, 10:56:15 pm
content: Quote from: wraper on December 12, 2020, 08:37:02 pmTo be fair, Vega VV17 was also a thing... ESA rocket were someone switched the cables for two thrust vectoring actuators. Or Starliner who was launched with software that would rival Cyberpunk2077 on the PS4 in the category of "most tested/best performing software". The problem of underfunding/lack of quality control is plaging the entire industry, Russia is just the most extreme example (nearly all problems with Protons could have probably been prevented with more thorough testing).And the Proton has one huge issue when it comes to launch failures: It still uses the N2O4/UDMH combo. Ivan sees a thing he likes, Ivan uses it. When Ivan needs more thrust, he builds himself a bigger rocket with the same propellants.That stuff might be a nice propellant, but the cleanup following a launch failure is a royal PITA. Hydrazine is not the tamest chemical, and the N2O4 will corrode everything in sight (that's the orange clouds in the video).Falcon 9 uses oxygen and jet fuel, so the cleanup is rather tame in comparison.Btw, don't be too hard on Angara when we still have SLS on the table...

author: wraper
author_rank: Unknown
timestamp: December 12, 2020, 11:04:48 pm
content: Quote from: jogri on December 12, 2020, 10:56:15 pmSLS is waste of money and resources on a grand scale. Actually Dragon and CST-100 were severely delayed exactly because most of the money/resources had gone to that junk based on old technology. And even when it's design is finished, it's will be not sustainable because of it's huge price.QuoteHell yeah,

author: rdl
author_rank: Super Contributor
timestamp: December 12, 2020, 11:27:34 pm
content: Quote from: S. Petrukhin on December 12, 2020, 06:21:10 amWhat makes SpaceX "so happy" is that this event was progress toward people living on Mars. Everything they do is focused on that goal. And just about everything that they do has required going where no one has gone before. Not just "inventing the wheel" as you seem to think. I've never believed that goal was realistic, but as more and more progress is made my opinion slowly changes. This test flight of Starship will probably prove to be an epic milestone.I didn't really take to Elon Musk at first and I'm still not a fan, but his company SpaceX has been one of the best things that has happened for America, everyone really. If nothing else, they have made 2020 much less miserable than it would have been.I would suggest that you educate yourself on the current state of space technology before making additional comments. There are many excellent resources available. Watch some of the spaceflight related videos on youtube by Scott Manley and Tim Dodd and others. It will be time well spent.

author: jogri
author_rank: Frequent Contributor
timestamp: December 12, 2020, 11:52:28 pm
content: Quote from: wraper on December 12, 2020, 11:04:48 pmWhat? Just because one of the four RS-25 engines of the first stages costs more than an entire, fully expendable Falcon Heavy launch?I just did the math, if i didn't screw up somewhere a Block 1 SLS has a net weight of roughly 2470 tons. Falcon Heavy can lift 63.8 tons to LEO, so you could theoretically get a complete, fueled SLS to orbit in 39 trips, each costing 90 million USD for fully reusable Falcons. This would cost you 3.5 billion, if we add the development cost of the SLS to the 2 billion per launch (~10 launches seem realistic, that would mean roughly extra 2 billion dev cost per launch) it is actually cheaper to launch the SLS on another rocket instead of flying it under its own power...

author: vad
author_rank: Frequent Contributor
timestamp: December 13, 2020, 01:38:58 am
content: Quote from: S. Petrukhin on December 12, 2020, 06:21:10 amReusable engines for one thing. Lowering cost of launch for other. 1.5B per launch of Space Shuttle in 2000’s dollars vs 57M per launch of Falcon 9 in 2020’s dollars.The Starship (the rocket that is discussed in this topic) is super heavy rocket capable of putting 150 tonnes to LEO. It has no competition. Even Mother Russia was not capable of lifting 150t in its entire 63 years of history of space exploration. The closest was Saturn V that was retired long time ago.

author: wraper
author_rank: Unknown
timestamp: December 13, 2020, 01:47:17 am
content: Quote from: vad on December 13, 2020, 01:38:58 amLatest spec claims 100+t. The thing is, as it's reusable, it's intended to be refueled by other Starships on orbit, therefore can deliver 100 t not only to LEO, but anywhere. While anything else takes a huge hit on payload mass, and cannot be refueled economically by expendable rockets. About reusability, unlike Falcon rockets, it intended for rapid reuse without any refurbishment, the same day if needed.

author: rdl
author_rank: Super Contributor
timestamp: December 13, 2020, 08:58:18 am
content: The SLS has become a financial disaster. It survivesmostlyonly because of politics. Using four of thevery expensive RS-25 engineson an expendable booster is stupid beyond belief.

author: wraper
author_rank: Unknown
timestamp: December 13, 2020, 02:26:14 pm
content: Quote from: rdl on December 13, 2020, 08:58:18 amWhat's the most surprising, is how they already spent more than $20 billion on severally delayed all-old technology, old engines, old solid rocket boosters, basically made nothing new, and it's still not finished. And what's supposed to launch soon is under-specced SLS block 1 with no human carrying capability, which makes no sense whatsoever. And development shall continue, yay.

author: coppice
author_rank: Super Contributor
timestamp: December 13, 2020, 02:55:33 pm
content: When I think of NASA projects like the SLS, I always think of

author: tom66
author_rank: Super Contributor
timestamp: December 13, 2020, 10:42:21 pm
content: Quote from: rdl on December 13, 2020, 08:58:18 amPork barrel politics. Far better to waste billions developing a rocket system that will barely see use, than to put that money to useful things (boy, I bet that could buy a lot of wind farms, which would probably still employ plenty of people.)

author: wraper
author_rank: Unknown
timestamp: December 13, 2020, 11:57:37 pm
content: Quote from: tom66 on December 13, 2020, 10:42:21 pmMoney can be wasted on anything, including wind farms. Problem is not that SLS is made as such, It's about HOW it's made.

author: raptor1956
author_rank: Frequent Contributor
timestamp: December 16, 2020, 02:11:01 am
content: My initial impression of the Starship SN8 12.5km test was that it was a partial success and therefore a partial failure, but the more I learn about it the more I'm left to conclude that it was much more success than failure. Watching it realtime the loss of the first engine appeared unplanned ... ditto the second engine, but when they fired up two engines at the end it showed that the earlier engine shutdowns were planned -- at least one of them anyway. So, it we take the news from SpaceX that the crash was do to low pressure in a header tank it puts the failure down to that singular issue -- still, they've been failing with tanks a bit too much for my taste. The green exhaust seen in the final seconds was put down to the copper in the engines burning up, but when I saw it realtime I thought they were using TEA/TEB like they use with the Merlin engines. Since the Raptor isn't supposed to use TEA/TEB and instead uses a spark torch setup I thought they'd used TEA/TEB as an emergency engine restart, but, consuming copper fully explains the green color so no TEA/TEB.Blue Origin, in operation two years longer than SpaceX, has yet to put anything into orbit!Brian

author: Refrigerator
author_rank: Super Contributor
timestamp: December 16, 2020, 06:54:44 am
content: Quote from: wraper on December 13, 2020, 11:57:37 pmAnd solar panels *cough* solar roadways *cough*.

author: Mr. Scram
author_rank: Super Contributor
timestamp: December 20, 2020, 04:29:11 pm
content: Quote from: raptor1956 on December 16, 2020, 02:11:01 amThe intended product of a test flight is data and as far as I understand this flight was a resounding success in that regard. More relevant data than expected was produced.