JoeSchmuckatelli Posted June 10 Share Posted June 10 1 hour ago, sevenperforce said: What evidence do you have to suggest that any engines exploded on relight during either Superheavy booster landing burn? 6 minutes ago, Ultimate Steve said: Probably the video footage of an engine exploding on relight during the IFT-4 Superheavy booster landing burn, a giant mass of fire remaining where the engine was, and chunks flying off. Yeah - that happened. Quibble that we don't know Fer Shure, but it's the most likely thing. Oh - Booster landing. No info vis SS Despite this - it pretty much 'stuck the landing' - maybe what they need is a landing platform with some deep water /a deluge system to put out the fire? Quote Link to comment Share on other sites More sharing options...
Exoscientist Posted June 12 Share Posted June 12 (edited) So as I argued before SpaceX should investigate an expendable version of Superheavy/Starship. The Raptor has been in development since 2016 and it is still experiencing explosions during relights. The Falcon 9 was spectacularly successful by first developing it as an expendable, doing several profitable, commercial flights in the expendable form, then progressing to the reusable form. Note all those successful, expendable flights gave good information on the Merlins reliability. A majorly important advantage of going first with the expendable form of the SH/SS is that we can do both single launch Moon and Mars missions now by using the Falcon 9 upper stage as a 3rd stage/lander stage and the Dragon as the crew module. (The Orion capsule is overbloated both in cost and mass.) Going with the expendable form of the SH/SS means you get greatly increased payload to LEO now , probably in the 250 to 300 ton range, by not having to keep the large amount propellant on reserve for the SH for return to launch site, and you wouldn't get the tripling of the dry mass of the SS for reusability systems we have now. For either of those manned flights to the Moon or Mars, this would be around the cost of a SH/SS single launch, $95 million. Compare this to the likely $7+ billion per mission cost of Artemis when you add up all of SLS, Orion, Starship HLS, Boeing EUS, advanced booster upgrade, and Gateway costs. And compare it to $500 billion(!) cost NASA once estimated for the full development costs of a manned Mars program. Quite importantly also, we could do it, literally, like, tomorrow. Not by 2028 for going to the Moon by the Artemis architecture, and not by the 2030's for Mars by the most optimistic estimates by Elon Musk. Bob Clark Edited June 12 by Exoscientist Quote Link to comment Share on other sites More sharing options...
JoeSchmuckatelli Posted June 12 Share Posted June 12 3 hours ago, Exoscientist said: ...expendable Superheavy/Starship Has anyone looked at or seen the numbers vis Booster performance and projected it as what its expendable first stage capability actually might be? Because thus far they've both gone slower than Saturn's first stage Quote Link to comment Share on other sites More sharing options...
Nuke Posted June 14 Share Posted June 14 (edited) always wondered about using falcon first stage as extra side boosters for starship. in fact i bet that was the reasoning for the offset grid fin placement on sh. turning a 2-stage reusable into a 3 stage might improve efficiency. Edited June 14 by Nuke Quote Link to comment Share on other sites More sharing options...
mikegarrison Posted June 14 Share Posted June 14 1 hour ago, Nuke said: always wondered about using falcon first stage as extra side boosters for starship. in fact i bet that was the reasoning for the offset grid fin placement on sh. turning a 2-stage reusable into a 3 stage might improve efficiency. One of the ways KSP lies to you is that it is not easy to just MOAR BOOSTERS onto the side of a rocket. The structure of a typical rocket is designed to carry loads axially, but adding side boosters moves the load paths. Quote Link to comment Share on other sites More sharing options...
magnemoe Posted June 14 Share Posted June 14 13 hours ago, mikegarrison said: One of the ways KSP lies to you is that it is not easy to just MOAR BOOSTERS onto the side of a rocket. The structure of a typical rocket is designed to carry loads axially, but adding side boosters moves the load paths. This, it best has to be designed in from the start, This is why falcon heavy was so delayed. Quote Link to comment Share on other sites More sharing options...
gfdgfherytrey Posted June 14 Share Posted June 14 Because spacex does not want to recover booster 11 and ship 29, does that mean that anyone can grab the ship and bring it home with them or is it still their property? Quote Link to comment Share on other sites More sharing options...
darthgently Posted June 14 Share Posted June 14 17 hours ago, mikegarrison said: One of the ways KSP lies to you is that it is not easy to just MOAR BOOSTERS onto the side of a rocket. The structure of a typical rocket is designed to carry loads axially, but adding side boosters moves the load paths. Any Kerbal knows that this is why you always add 16 or more side boosters so as to more smoothly and evenly space the added load via the circumferential squeezing theorem. You want the center core to crowdsurf on a plethora of boosters. Quote Link to comment Share on other sites More sharing options...
Ultimate Steve Posted June 14 Share Posted June 14 3 hours ago, gfdgfherytrey said: Because spacex does not want to recover booster 11 and ship 29, does that mean that anyone can grab the ship and bring it home with them or is it still their property? Presumably they are at the bottom of the ocean by now. If you can get them, you probably deserve them. There is some precedent for that, Jeff Bezos funded a submarine mission to recover engines from the Saturn V. Unsure what exactly the law is there. Probably classified as some sort of salvage, but ITAR might have something to say about the fiddly bits of the engines. F1 was an obsolete design and Raptor is cutting edge. Quote Link to comment Share on other sites More sharing options...
Jacke Posted June 14 Share Posted June 14 1 hour ago, Ultimate Steve said: Presumably they are at the bottom of the ocean by now. If you can get them, you probably deserve them. There is some precedent for that, Jeff Bezos funded a submarine mission to recover engines from the Saturn V. Unsure what exactly the law is there. Probably classified as some sort of salvage, but ITAR might have something to say about the fiddly bits of the engines. F1 was an obsolete design and Raptor is cutting edge. It's not just ITAR (but that's rather serious). It's also the Outer Space Treaty. Components and debris from a launch or spacecraft aren't just Salvage, they're still under the jurisdiction of the signatory Nation who created or licenced them. Quote Link to comment Share on other sites More sharing options...
Lisias Posted June 15 Share Posted June 15 (edited) 6 hours ago, Ultimate Steve said: Presumably they are at the bottom of the ocean by now. If you can get them, you probably deserve them. Risk management: knowing Musk, he had already assessed the situation. I would not be surprised if the engines have some self-destruction mechanism - perhaps some of the engine's failures Spaceship had may due they ironing out these devices being triggered prematurely by accident. At the time of the Apollo Missions, no one (besides Jules Verne and, perhaps, the Military) had the technology to do deep ocean recoveries, but nowadays even civilians are being able (with deadly reserves) to reach huge deepness in the ocean. 6 hours ago, Ultimate Steve said: There is some precedent for that, Jeff Bezos funded a submarine mission to recover engines from the Saturn V. Exactly my point. 6 hours ago, Ultimate Steve said: Unsure what exactly the law is there. Probably classified as some sort of salvage, but ITAR might have something to say about the fiddly bits of the engines. F1 was an obsolete design and Raptor is cutting edge. There're adversarial players in the scene nowadays with wider backs than Bezos. You don't need to care about these details if no one will have the guts to bring them to your attention. I risk speculate that the reason we don't have footage of the engines at touch down may be related to whatever safety mechanism the engines (hypothetically) have. Assuming, of course, that the mere contact from the engine's bells with the water would not do the trick itself - I wonder what would happen if all the engines would lighten up with the bells' mouths touching the water, the pressure would be enough to tear everything apart. Edited June 15 by Lisias Tyops, as usulla... Quote Link to comment Share on other sites More sharing options...
JoeSchmuckatelli Posted June 16 Share Posted June 16 On 6/14/2024 at 8:19 PM, Lisias said: mere contact from the engine's bells with the water They don't want the hot, rapidly cooled bells... They want all the fiddly bits above the bell. Given that SX had a video of the Booster landing... I'm guessing they had the ability to recover or ensure sinkage. The big unknown is SS itself. Quote Link to comment Share on other sites More sharing options...
Lisias Posted June 16 Share Posted June 16 (edited) 1 hour ago, JoeSchmuckatelli said: They don't want the hot, rapidly cooled bells... They want all the fiddly bits above the bell. Humm... Yeah, reading now what I wrote, this is a possible interpretation. Language barrier is a sun on our beaches... Allow me to try again. Water is way more dense than air (obviously), so the pressure of the exhaust would eventually not be able to break free from the bell's mouth. Something will have to give in, probably the bell's wall. But this wall is probably stronger near the combustion chamber, right? If we have water enough in the bell, the water will protect the weaker parts of the wall from breaking. If the upper part of the bell is strong enough, the engine itself will be the one giving in - destroying exactly the interesting bits. Edited June 16 by Lisias tyops. as usulla. Quote Link to comment Share on other sites More sharing options...
AckSed Posted June 17 Share Posted June 17 Robert Truax, designer of the famous Sea Dragon, did the Sea Horse tests as a prelude. Thanks to that, we know that rockets can be fired under water. The normal Raptors would probably survive their dunking. The Vacuum Raptors' bells might break off, as I'd imagine they'd be more fragile. Quote Link to comment Share on other sites More sharing options...
darthgently Posted June 17 Share Posted June 17 7 minutes ago, AckSed said: Robert Truax, designer of the famous Sea Dragon, did the Sea Horse tests as a prelude. Thanks to that, we know that rockets can be fired under water. The normal Raptors would probably survive their dunking. The Vacuum Raptors' bells might break off, as I'd imagine they'd be more fragile. It would be interesting to know if they made any modifications to the engine or bell to accommodate the test. If they had it would probably been classified given the era Quote Link to comment Share on other sites More sharing options...
tater Posted June 19 Share Posted June 19 I could actually see F9 launch from VSFB from my patio in ABQ. Amazing. Saw S2. Very cool. Quote Link to comment Share on other sites More sharing options...
darthgently Posted June 20 Share Posted June 20 Is there a Tesla/SpaceX Robo Dragon that could fetch a couple of people stuck on the ISS? Quote Link to comment Share on other sites More sharing options...
GuessingEveryDay Posted June 20 Share Posted June 20 2 hours ago, darthgently said: Is there a Tesla/SpaceX Robo Dragon that could fetch a couple of people stuck on the ISS? I believe SpaceX originally designed the Dragon capsule to hold 8, but NASA only needed 4. Don't remember where I heard it though. Oh, it's only 7. Found it on their website. Enough room for the crew and Soyuz. Starliner is also designed for 7, but somehow looks a lot more cramped. Quote Link to comment Share on other sites More sharing options...
GuessingEveryDay Posted June 20 Share Posted June 20 After searching for the videos, you can see how Dragon and Starliner feel so different. Even though Starliner has more capsule volume than Dragon (11 m^3 to 10), kinda weird. Quote Link to comment Share on other sites More sharing options...
magnemoe Posted June 20 Share Posted June 20 6 hours ago, GuessingEveryDay said: I believe SpaceX originally designed the Dragon capsule to hold 8, but NASA only needed 4. Don't remember where I heard it though. Oh, it's only 7. Found it on their website. Enough room for the crew and Soyuz. Starliner is also designed for 7, but somehow looks a lot more cramped. Not sure how easy it is to change it to 7, probably just install more seats below. Don't think they have removed the mounting points for extra seats as it might be useful. And as falcon 9 fly so often it should be easy to change one to an dragon flight so it mostly depend if they have an ready to fly dragon capsule. Quote Link to comment Share on other sites More sharing options...
tater Posted June 20 Share Posted June 20 3 hours ago, magnemoe said: Not sure how easy it is to change it to 7, probably just install more seats below. Don't think they have removed the mounting points for extra seats as it might be useful. And as falcon 9 fly so often it should be easy to change one to an dragon flight so it mostly depend if they have an ready to fly dragon capsule. The CCV contract was for 7 for both vehicles, operational needs still result in fewer seats actually installed. Started from the original CEV concept for Constellation that became Orion—remember, Orion was supposed to fly to LEO, replacing Shuttle as the taxi for astronauts to ISS, then it meets a lunar vehicle in LEO (sent by Ares V which became the awful SLS) to do cislunar. It's possible Starliner has some heritage in Boeing's bid for MPCV I think—there's nothing out there about what the Boeing Northrup design was for the SEI bid, though in some other contract they had they had bid a capsule, so concepts for CST-100 might literally date back to the 80s). Quote Link to comment Share on other sites More sharing options...
Cuky Posted June 20 Share Posted June 20 But there is an elephant in the room: how do you fit astronauts in Boeing suits inside SpaceX seats and even more, how do you connect them to life support because I don't think umbilical found in Crew Dragon would be able to connect anywhere on Boeing suit. Quote Link to comment Share on other sites More sharing options...
tater Posted June 20 Share Posted June 20 (edited) 1 hour ago, Cuky said: But there is an elephant in the room: how do you fit astronauts in Boeing suits inside SpaceX seats and even more, how do you connect them to life support because I don't think umbilical found in Crew Dragon would be able to connect anywhere on Boeing suit. If they were to send up a Dragon, they'd probably just send one up, not add seats. As far as I know they're still aiming for the 26th to send Starliner home (?). Edited June 20 by tater Quote Link to comment Share on other sites More sharing options...
Ultimate Steve Posted June 20 Share Posted June 20 52 minutes ago, Cuky said: But there is an elephant in the room: how do you fit astronauts in Boeing suits inside SpaceX seats and even more, how do you connect them to life support because I don't think umbilical found in Crew Dragon would be able to connect anywhere on Boeing suit. Presumably if they've been doing their homework, they have come up with an adapter. Although in an emergency situation they would probably just take the risk. All the suits do is protect against depressurization. Quote Link to comment Share on other sites More sharing options...
StrandedonEarth Posted Thursday at 06:53 PM Share Posted Thursday at 06:53 PM 2 hours ago, Cuky said: But there is an elephant in the room: how do you fit astronauts in Boeing suits inside SpaceX seats and even more, how do you connect them to life support because I don't think umbilical found in Crew Dragon would be able to connect anywhere on Boeing suit. It was my understanding that aerospace connectors were standardized after the Apollo 13 accident, where they had to use space tape to make CSM and LM life support components work together. Or that could have been wishful thinking in some fiction I read. But it would make sense to have umbilical connectors as standardized as possible in case of an emergency. It would be awfully shortsighted to have someone die of hypoxia because the only available oxygen hose wouldn’t connect to their suit because of mismatched connectors… Quote Link to comment Share on other sites More sharing options...
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