T-10a Posted February 25, 2018 Share Posted February 25, 2018 (edited) 14 minutes ago, Bill Phil said: The idea is to make it so cheap to operate that they can replace the F9 family entirely. It's possible, albeit unlikely, that a BFS could be used as an SSTO or be used to take a kick motor to near orbit, potentially orbiting payloads near F9 size without a booster being necessary. Even if it needs a booster for every launch, if they can get the cost to a level less than a current F9 launch, then if someone wants to launch a small payload they can do so at a cheaper cost than today, but going bigger would be better for the customer. I may be wrong (and this is sort of the wrong thread to talk about this thing), but I thought the BFR did not have the dV on its own to launch an SSTO mission. And I really doubt such a big booster with so much dev money will be cheap in the near future (Methalox has never flown on a mission before, it needs to approach airline-levels of reliability to warrant serious long-term reuse so there will have to be lots built to cover losses which will increase costs, in-orbit refuelling on that scale has never been attempted yet, I'm sure managing the life support logistics for 100+ passengers is going to be a nightmare (for the passenger vehicle at least), and finally Mars missions/colonisation is inherently non-viable commercially due to the extreme costs in development and maintaining something as simple as an Antarctic-style base at Mars). All in all, until they can prove they can build and fly such a thing successfully, I believe it's going to be vaporware akin to Constellation, or delayed to the 2030s/2040s. But hey, if they do solve these issues and make it viable, it'd be one heck of a showstealer Edited February 25, 2018 by T-10a Quote Link to comment Share on other sites More sharing options...
tater Posted February 25, 2018 Share Posted February 25, 2018 There's a thread about BFR. This would be about New Glenn, or even New Armstrong. BO is building a reusable booster using methlox. The Be-4 has been test fired, as has SpaceX's Raptor. Methlox leaves less residue, so is better for reuse. It doesn't need airline levels of reliability for reuse, either. Quote Link to comment Share on other sites More sharing options...
T-10a Posted February 25, 2018 Share Posted February 25, 2018 Has there been any images of New Armstrong/ Blue Moon yet? Quote Link to comment Share on other sites More sharing options...
tater Posted February 25, 2018 Share Posted February 25, 2018 No. They need to build an orbital rocket before they show that, I think. Quote Link to comment Share on other sites More sharing options...
T-10a Posted February 25, 2018 Share Posted February 25, 2018 true. Their secrecy doesn't help with that. Quote Link to comment Share on other sites More sharing options...
sh1pman Posted February 25, 2018 Share Posted February 25, 2018 There is a speculation on Reddit about its capabilities, but nothing official yet. It might dwarf that other monster rocket that recently got its own thread due to its awesomeness. Quote Link to comment Share on other sites More sharing options...
Bill Phil Posted February 25, 2018 Share Posted February 25, 2018 2 hours ago, T-10a said: Has there been any images of New Armstrong/ Blue Moon yet? There's one, but it's not very helpful. You can find it by googling "Blue Origin Blue Moon" and searching under the images tab. It may not be an actual image of the vehicle though. Quote Link to comment Share on other sites More sharing options...
tater Posted February 25, 2018 Share Posted February 25, 2018 9 hours ago, Bill Phil said: There's one, but it's not very helpful. You can find it by googling "Blue Origin Blue Moon" and searching under the images tab. It may not be an actual image of the vehicle though. I remember seeing that, but was unsure if it was real or not. Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted February 25, 2018 Share Posted February 25, 2018 12 minutes ago, tater said: I remember seeing that, but was unsure if it was real or not. It's the image supplied by BO but it doesn't tell us much. Blue Moon is supposed to be able to drop 4.5 tonnes on the surface of the moon and presumably uses a BE-3 architecture. They talk about delivering it with NG or SLS, which means it's probably not intended to go from LLO to the lunar surface, but rather to go from TLI to the lunar surface. To be useful, it needs to be able to target the poles as well. We're probably talking about 3.5 km/s or a little more. Let's say 3.8 km/s, to allow for extended hover on landing. The BE-3 is combustion tap-off, so it is necessarily less efficient than an expander-cycle (RL-10) or staged-combustion (SSME) hydrolox engine, and is probably more comparable to a GG cycle like the RS-68. A vacuum-expanded nozzle will give it a better isp, likely in the 420-s range. 420 s and 3.8 km/s means a prop fraction of 60.3%. A vacuum-expanded BE-3 would have a thrust of 500 kN or so. 500 kN gets you far more thrust than a 5-tonne-payload-class moon lander would ever need. Assuming a TWR of around 50 for the BE-3 and a hydrolox tank mass fraction of around 20, we're talking about around 10.5 tonnes of wet mass plus 4.5 tonnes of payload and a vehicle dry mass of about 1.5 tonnes. Note that the BE-3 uses expendable pyros for ignition so it is not a candidate for cislunar reuse. Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted February 25, 2018 Share Posted February 25, 2018 Update: additional (paywalled) discussion indicated that 50-kN methalox thrusters, likely the ones intended for RCS on New Glenn, wold be used for the actual landing. The BE-3 cannot throttle deeply enough for moon landings. The 4.5-tonne payload would only be enabled by SLS; smaller rockets would have the BE-3 performing part or all of the TLI burn. So we are likely looking at a hydrolox BE-3 crasher stage with as many pressure-fed methalox thrusters as needed for the desired payload. Quote Link to comment Share on other sites More sharing options...
DAL59 Posted February 26, 2018 Share Posted February 26, 2018 On 2/24/2018 at 10:30 PM, Bill Phil said: t's possible, albeit unlikely, that a BFS could be used as an SSTO or be used to take a kick motor to near orbit, potentially orbiting payloads near F9 size without a booster being necessary. He confirmed that. Quote Link to comment Share on other sites More sharing options...
tater Posted March 10, 2018 Share Posted March 10, 2018 Blue talk live now: http://legacyweb.media.mit.edu/events/medialabtalk/ Quote Link to comment Share on other sites More sharing options...
tater Posted March 10, 2018 Share Posted March 10, 2018 Blue expects to fly people into orbit in 7-8 years (from BO's VP of advanced dev). They are actively working this. Quote Link to comment Share on other sites More sharing options...
Canopus Posted March 10, 2018 Share Posted March 10, 2018 (edited) And Space tugs too. I just wish they had some more details. Edited March 10, 2018 by Canopus Quote Link to comment Share on other sites More sharing options...
tater Posted March 10, 2018 Share Posted March 10, 2018 Bezos needs to make them a bit more "ferociter," he's not getting any younger Quote Link to comment Share on other sites More sharing options...
CatastrophicFailure Posted March 10, 2018 Share Posted March 10, 2018 Any word if they’ve started prototyping for New Glenn yet, now that the factory’s finished? Quote Link to comment Share on other sites More sharing options...
StrandedonEarth Posted March 10, 2018 Share Posted March 10, 2018 The exterior may be finished, no idea if the tooling and such inside is. Quote Link to comment Share on other sites More sharing options...
Ultimate Steve Posted March 11, 2018 Share Posted March 11, 2018 Any word on when the next NS flight is? Quote Link to comment Share on other sites More sharing options...
tater Posted March 11, 2018 Share Posted March 11, 2018 12 hours ago, Canopus said: And Space tugs too. I just wish they had some more details. This is pretty important. 45 tons to LEO, a 7m fairing, and a plan for a cislunar infrastructure (tugs). Quote Link to comment Share on other sites More sharing options...
tater Posted March 11, 2018 Share Posted March 11, 2018 (another space conference at MIT today (not livestreamed)). Quote Link to comment Share on other sites More sharing options...
tater Posted March 13, 2018 Share Posted March 13, 2018 Quote Link to comment Share on other sites More sharing options...
tater Posted March 13, 2018 Share Posted March 13, 2018 Quote Link to comment Share on other sites More sharing options...
RedKraken Posted March 15, 2018 Share Posted March 15, 2018 (edited) Anyone want to have a guess at the isp ? Edited March 15, 2018 by RedKraken Quote Link to comment Share on other sites More sharing options...
sh1pman Posted March 15, 2018 Share Posted March 15, 2018 12 minutes ago, RedKraken said: Anyone want to have a guess at the isp ? It's methalox, so I'd say it's somewhere between 350 and 370s. Quote Link to comment Share on other sites More sharing options...
RedKraken Posted March 15, 2018 Share Posted March 15, 2018 (edited) I'm thinking sea-level methane, ORSC, not as high as raptors FFSC. Less efficient cycle plus much lower chamber pressure .......plus conservative engine design. Raptor 2017 is reportedly 330s at sea level is an upper limit so far. (Merlin is 282s ? RD-180 is 311s) For BE-4 ...... 310s at sea level? I wish the Bez would just tell us. Nilof @ NSF ran some numbers thru MPA engine simulator ....reply #14....came up with 315s at SL. https://forum.nasaspaceflight.com/index.php?topic=39674.0 Edited March 15, 2018 by RedKraken Quote Link to comment Share on other sites More sharing options...
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