sevenperforce Posted May 9, 2018 Share Posted May 9, 2018 57 minutes ago, ThatGuyWithALongUsername said: However, I think they will get it a bit faster than SpaceX did, in part thanks to how they land: Instead of performing the most efficient possible suicide burn, rhey hover over the landing site for a few seconds. This makes it easier to do, with greater room for error. It won't take them too long. Does anyone know whether the New Glenn has aft RCS? Quote Link to comment Share on other sites More sharing options...
Streetwind Posted May 11, 2018 Share Posted May 11, 2018 On 5/9/2018 at 5:09 PM, ThatGuyWithALongUsername said: Landing a tiny suborbital rocket is a lot easier than landing a giant SHLV on a moving barge ship, so I don't think they'll succeed on their first try (especially considering the new shephard failure mentioned earlier). However, I think they will get it a bit faster than SpaceX did, in part thanks to how they land: Instead of performing the most efficient possible suicide burn, rhey hover over the landing site for a few seconds. This makes it easier to do, with greater room for error. It won't take them too long. Jeff Bezos went on record last year that he personally thinks that the New Shepard landings are the hardest they'll ever have to do. He cites the inverted pendulum problem: balancing a broom on its tip on your palm is a lot easier than balancing a pencil on its tip on your palm, because the broom has a much larger moment of inertia. The same is true for a larger rocket. Because it is much slower to grow unstable, the rocket's systems have much more time to respond and maintain stability. I suspect the only way they're going to screw up their first New Glenn landing is missing the barge entirely on reentry. If they get anywhere near it, the rocket will land. Blue Origin is the kind of company that doesn't launch until they're certain of that (much to our chargrin, sometimes). Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted May 11, 2018 Share Posted May 11, 2018 5 hours ago, Streetwind said: Jeff Bezos went on record last year that he personally thinks that the New Shepard landings are the hardest they'll ever have to do. He cites the inverted pendulum problem: balancing a broom on its tip on your palm is a lot easier than balancing a pencil on its tip on your palm, because the broom has a much larger moment of inertia. The same is true for a larger rocket. Because it is much slower to grow unstable, the rocket's systems have much more time to respond and maintain stability. I suspect the only way they're going to screw up their first New Glenn landing is missing the barge entirely on reentry. If they get anywhere near it, the rocket will land. Blue Origin is the kind of company that doesn't launch until they're certain of that (much to our chargrin, sometimes). Which you can afford to do if you have money to burn. Quote Link to comment Share on other sites More sharing options...
tater Posted May 12, 2018 Share Posted May 12, 2018 https://apps.fcc.gov/oetcf/els/reports/STA_Print.cfm?mode=current&application_seq=84733&RequestTimeout=1000 June 1 for another NS flight. Quote Link to comment Share on other sites More sharing options...
MaverickSawyer Posted May 13, 2018 Share Posted May 13, 2018 Surprised that no one mentioned the news that BO lost out on the selection of the upper stage engine for Vulcan. Quote Link to comment Share on other sites More sharing options...
tater Posted May 13, 2018 Share Posted May 13, 2018 27 minutes ago, MaverickSawyer said: Surprised that no one mentioned the news that BO lost out on the selection of the upper stage engine for Vulcan. Was posted in the ULA thread. Makes sense to me, else ULA is basically making a less capable, more wasteful NG, lol. Quote Link to comment Share on other sites More sharing options...
MaverickSawyer Posted May 13, 2018 Share Posted May 13, 2018 ULA is, quite frankly, in the business of keeping Aerojet Rocketdyne in the liquid-fuelled engine industry. Vulcan cannot be reasonably expected to compete against Falcon 9, Falcon Heavy, or New Glenn, let alone BFR. Quote Link to comment Share on other sites More sharing options...
sh1pman Posted May 13, 2018 Share Posted May 13, 2018 5 hours ago, MaverickSawyer said: Vulcan cannot be reasonably expected to compete against Falcon 9, Falcon Heavy, or New Glenn, let alone BFR. Depends on what kind of competition we're talking about. Vulcan-ACES is certainly more capable than F9, and is close to FH in GTO throw mass. It has infinitely restartable US engines, and can stay in space much longer due to IVF, allowing for things like fuel depots, tugs and long missions in deep space. But of course, from the cost per launch perspective, reusable rockets always win, that's the point of reusability. Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted May 14, 2018 Share Posted May 14, 2018 On 5/13/2018 at 6:13 AM, sh1pman said: Depends on what kind of competition we're talking about. Vulcan-ACES is certainly more capable than F9, and is close to FH in GTO throw mass. It has infinitely restartable US engines, and can stay in space much longer due to IVF, allowing for things like fuel depots, tugs and long missions in deep space. But of course, from the cost per launch perspective, reusable rockets always win, that's the point of reusability. How much are the GEM-60 SRBs currently used for Delta IV? They can't be terribly expensive. Vulcan cannot compete financially with Falcon 9 for LEO, but with SMART reuse recovering 65% of the cost of the booster, Vulcan-ACES can definitely compete for destinations that stretch the capabilities of F9 and FH, like heavy GTO payloads, direct-to-GEO insertions, and anything beyond. Quote Link to comment Share on other sites More sharing options...
tater Posted May 14, 2018 Share Posted May 14, 2018 The wildcard is NG, really. We don't know what the upper stage will really look like. If they decide that it makse sense to "reuse" the upper stage in space (ever), they will just make their own ACES I think. Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted May 14, 2018 Share Posted May 14, 2018 14 minutes ago, tater said: The wildcard is NG, really. We don't know what the upper stage will really look like. If they decide that it makse sense to "reuse" the upper stage in space (ever), they will just make their own ACES I think. I wonder if BE-3 will be redesigned to use augmented spark ignition or if they will just stick with using pyros. Quote Link to comment Share on other sites More sharing options...
tater Posted May 14, 2018 Share Posted May 14, 2018 1 hour ago, sevenperforce said: I wonder if BE-3 will be redesigned to use augmented spark ignition or if they will just stick with using pyros. You'd think they would be rethinking this. Infinite restart is what is needed for "millions of people to live and work in space." This has to be on their minds, right? Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted May 14, 2018 Share Posted May 14, 2018 5 minutes ago, tater said: You'd think they would be rethinking this. Infinite restart is what is needed for "millions of people to live and work in space." This has to be on their minds, right? With the BE-3 being an engine they plan on using indefinitely, rather than limiting to NS, you'd imagine it's already been discussed. Then again, if they have no plans for developing orbital hydrolox transfer, it may not be necessary. No sense developing infinite restarts if you only have so much props per engine. Question -- does anyone know if ACES is planned to come with enough RCS capabilities to perform its own maneuvers for autonomous rendezvous, docking, and proptrans? Quote Link to comment Share on other sites More sharing options...
tater Posted May 14, 2018 Share Posted May 14, 2018 1 minute ago, sevenperforce said: Question -- does anyone know if ACES is planned to come with enough RCS capabilities to perform its own maneuvers for autonomous rendezvous, docking, and proptrans? Yeah, it does, since their videos, and presentations always talk about ACES refilling another ACES, not ACES attached to a capsule doing it. Quote Link to comment Share on other sites More sharing options...
Canopus Posted May 14, 2018 Share Posted May 14, 2018 7 minutes ago, sevenperforce said: Then again, if they have no plans for developing orbital hydrolox transfer, it may not be necessary. No sense developing infinite restarts if you only have so much props per engine. This suggest they are thinking about it: Also take note how New Armstrong isn't mentioned anywhere. They may have abandoned it in favor of reusable tugs. Quote Link to comment Share on other sites More sharing options...
wumpus Posted May 14, 2018 Share Posted May 14, 2018 58 minutes ago, sevenperforce said: With the BE-3 being an engine they plan on using indefinitely, rather than limiting to NS, you'd imagine it's already been discussed. Combustion tap-off cycles don't appear to be built for "indefinite" lifespans. Especially when start/stop methods are considered. Yes, Raptor's staged combustion engine might have similar issues, but at least it doesn't subject turbines to the full temperature of the combustion chamber. 3 hours ago, sevenperforce said: but with SMART reuse recovering 65% of the cost of the booster Is there anything to indicate that this is more than just a throwaway powerpoint bullet to get a few staffers off their back? If they were serious about it, wouldn't the be already doing testing runs with helicopter capture? I know smaller things have been air captured, but some indication that ULA had any capability to capture an entire engine might indicate that they were serious. I've heard a lot of marketing about rocket reuse (wasn't Ariane originally supposed to be reusable, or maybe that was a bad translation), but so far only the Shuttle and Falcon 9 if off while going to orbit (X-15, Spaceship 1, and New Shepard have all done it suborbital). I'll believe it when they launch a second rocket for 65% of the price of the previous rocket. Right now it sounds too much like "me to" and spacex's plans for asparagus on Falcon Heavy (which sounds much, much easier. I'm guessing they could do it with a restart on the center engines, but 6 restarts was considered too high a price). Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted May 14, 2018 Share Posted May 14, 2018 13 minutes ago, wumpus said: Combustion tap-off cycles don't appear to be built for "indefinite" lifespans. Especially when start/stop methods are considered. I meant that they said they plan on using the BE-3 engine model indefinitely. 13 minutes ago, wumpus said: Yes, Raptor's staged combustion engine might have similar issues, but at least it doesn't subject turbines to the full temperature of the combustion chamber. BE-3 is, I believe, the first-ever fully-operational combustion tap-off engine. 13 minutes ago, wumpus said: Is there anything to indicate that this is more than just a throwaway powerpoint bullet to get a few staffers off their back? If they were serious about it, wouldn't the be already doing testing runs with helicopter capture? I know smaller things have been air captured, but some indication that ULA had any capability to capture an entire engine might indicate that they were serious. I'll believe it when they launch a second rocket for 65% of the price of the previous rocket. Right now it sounds too much like "me to" and spacex's plans for asparagus on Falcon Heavy. Oh, they'll never launch a second Vulcan for 65% of the price of the previous rocket. They've very cleverly pointed out that as far as their raw cost for the booster alone, 65% is inside the engine compartment. So cost per launch reductions are probably closer to 20-30% for reusing the engine pod. Vulcan is still far enough away that test runs are not really feasible. Quote Link to comment Share on other sites More sharing options...
Canopus Posted May 14, 2018 Share Posted May 14, 2018 27 minutes ago, wumpus said: Is there anything to indicate that this is more than just a throwaway powerpoint bullet to get a few staffers off their back? If they were serious about it, wouldn't the be already doing testing runs with helicopter capture? ULA seems to be working with NASA on HIAD:https://www.nasa.gov/directorates/spacetech/game_changing_development/HIAD/index.html and there is a proposed demonstration mission where they would fly HIAD as a secondary payload on a LEO mission of an ATLAS. https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20160007968.pdf Quote Link to comment Share on other sites More sharing options...
Racescort666 Posted May 14, 2018 Share Posted May 14, 2018 (edited) They have a very convenient rocket for testing this stuff too: https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20100037917.pdf Edited May 14, 2018 by Racescort666 Quote Link to comment Share on other sites More sharing options...
Canopus Posted May 14, 2018 Share Posted May 14, 2018 (edited) 6 minutes ago, Racescort666 said: They have a very convenient rocket for testing this stuff too: https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20100037917.pdf that's a very interesting idea. I guess the diameter would be too small for HIAD though Edited May 14, 2018 by Canopus Quote Link to comment Share on other sites More sharing options...
Racescort666 Posted May 14, 2018 Share Posted May 14, 2018 The thing that kills me is that ULA says that they aren't interested in propulsive landing because it will impact the booster performance (basically increasing dry mass for recovery) but then they go on to say that the Atlas V has this huge extra capacity and they rarely use it to the full potential. Well which is it? Surely the few situations where the Atlas V needs the full performance a fully expendable configuration can be flown but in the others, you could at least try. Quote Link to comment Share on other sites More sharing options...
Canopus Posted May 14, 2018 Share Posted May 14, 2018 3 minutes ago, Racescort666 said: The thing that kills me is that ULA says that they aren't interested in propulsive landing because it will impact the booster performance (basically increasing dry mass for recovery) but then they go on to say that the Atlas V has this huge extra capacity and they rarely use it to the full potential. Well which is it? Surely the few situations where the Atlas V needs the full performance a fully expendable configuration can be flown but in the others, you could at least try. Atlas is tailored for the payload though. Launches like Insight, where the payload is much lighter are the exception not the rule. Atlas was probably chosen since delta II was being retired and other smaller launchers lack the proven track record for a mission of this caliber. Quote Link to comment Share on other sites More sharing options...
MaverickSawyer Posted May 15, 2018 Share Posted May 15, 2018 10 hours ago, Canopus said: that's a very interesting idea. I guess the diameter would be too small for HIAD though I think that "interesting" doesn't quite cover it. That's a brilliant idea, and it's a shame they haven't used it. I can think of about half a dozen ideas for that off the top of my head right now. Quote Link to comment Share on other sites More sharing options...
wumpus Posted May 16, 2018 Share Posted May 16, 2018 On 5/14/2018 at 5:11 PM, Racescort666 said: The thing that kills me is that ULA says that they aren't interested in propulsive landing because it will impact the booster performance (basically increasing dry mass for recovery) but then they go on to say that the Atlas V has this huge extra capacity and they rarely use it to the full potential. Well which is it? Surely the few situations where the Atlas V needs the full performance a fully expendable configuration can be flown but in the others, you could at least try. I'm guessing that they have a pretty good idea what Spacex went through to do this and know it simply won't work on a Govt/DoD contract schedule. Come to think of it, it could cost $100 to do and it *still* couldn't be done on a Govt/DoD contract schedule, at least not without technically committing multiple felonies (and for any real price it wouldn't be "technically"). Quote Link to comment Share on other sites More sharing options...
tater Posted May 24, 2018 Share Posted May 24, 2018 Quote Link to comment Share on other sites More sharing options...
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