sevenperforce Posted June 27, 2017 Share Posted June 27, 2017 Unrelated: any idea about how BO is going to manage entry without an entry burn on the NG? Quote Link to comment Share on other sites More sharing options...
wumpus Posted June 27, 2017 Share Posted June 27, 2017 4 hours ago, sevenperforce said: Unrelated: any idea about how BO is going to manage entry without an entry burn on the NG? Declare N2 RCS thrusters as "not a burn"? Electromagnetic braking (certainly possible. Wouldn't like to be the test pilot)? Where did you get this from anyway? I can't find any indication of weird NG re-entry plans. Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted June 28, 2017 Share Posted June 28, 2017 1 hour ago, wumpus said: Declare N2 RCS thrusters as "not a burn"? Electromagnetic braking (certainly possible. Wouldn't like to be the test pilot)? Where did you get this from anyway? I can't find any indication of weird NG re-entry plans. I mean a burn during entry. "There are also some significant differences between the vehicles, most notably the aerodynamic control surfaces used to help guide New Glenn's first-stage in for a landing. Reportedly, that negates the need for a re-entry deceleration burn." https://www.engadget.com/2017/03/07/blue-origin-shows-how-new-glenn-rocket-will-fly-and-land/ Quote Link to comment Share on other sites More sharing options...
Starman4308 Posted June 28, 2017 Share Posted June 28, 2017 There's a good chance that statement has more to do with something misheard than anything in reality. Otherwise, though, maybe they're saying that New Glenn should have more in-atmosphere maneuverability, thus they shouldn't need a retroburn to correct their reentry trajectory to land on the target barge, because New Glenn has enough control authority from control surfaces alone. I doubt that they meant anything like "we magically won't need to fire engines to kill our velocity at the end". Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted June 28, 2017 Share Posted June 28, 2017 1 hour ago, Starman4308 said: There's a good chance that statement has more to do with something misheard than anything in reality. Otherwise, though, maybe they're saying that New Glenn should have more in-atmosphere maneuverability, thus they shouldn't need a retroburn to correct their reentry trajectory to land on the target barge, because New Glenn has enough control authority from control surfaces alone. I doubt that they meant anything like "we magically won't need to fire engines to kill our velocity at the end". LOL, no, that's not what I meant either. A nominal Falcon 9 first stage ASDS landing uses two burns: an entry burn and a landing burn. Reportedly, the New Glenn will only need a landing burn. Quote Link to comment Share on other sites More sharing options...
magnemoe Posted June 28, 2017 Share Posted June 28, 2017 3 hours ago, Starman4308 said: There's a good chance that statement has more to do with something misheard than anything in reality. Otherwise, though, maybe they're saying that New Glenn should have more in-atmosphere maneuverability, thus they shouldn't need a retroburn to correct their reentry trajectory to land on the target barge, because New Glenn has enough control authority from control surfaces alone. I doubt that they meant anything like "we magically won't need to fire engines to kill our velocity at the end". An falcon 9 first stage does three burn, first is the boostback burn or correction burn to aim it at barge. Second is the reentry burn, this slow the stage down and can be used to increase landing accuracy. Finaly you have the landing burn to land it. If barge is at the end of the ballistic trajectory the stage will follow you don't need an boostback or correction burn, you just rotate the rocket an let it fall back. It should be possible to design the stage so it don't need the reentry burn, it would need to handle the 6000 km/h reentry, it looks like New Glen has an skirt who cover the engines this will keep most of the heat off them. You will need the braking burn from terminal velocity obviously but that is not so fast. One benefit of the grind fins is that they also have high drag, Quote Link to comment Share on other sites More sharing options...
Kryten Posted June 28, 2017 Share Posted June 28, 2017 Many vehicles already re-enter intact without a braking burn; CZ-2 first stages have been documented doing so, and according to ULA the atlas 5 first stage does. Falcon isn't tough enough to do it because of it's extreme mass ratio, but it doesn't seem all that hard in practice. Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted June 28, 2017 Share Posted June 28, 2017 8 hours ago, magnemoe said: It should be possible to design the stage so it don't need the reentry burn, it would need to handle the 6000 km/h reentry, it looks like New Glen has an skirt who cover the engines this will keep most of the heat off them. Yeah, this is the part I'm wondering about. Seems like plasma impingement on the engine bells would be problematic. Quote Link to comment Share on other sites More sharing options...
RedKraken Posted June 28, 2017 Share Posted June 28, 2017 Engine production shot from BO : source https://twitter.com/blueorigin/status/879351820950192128 Quote Link to comment Share on other sites More sharing options...
wumpus Posted June 30, 2017 Share Posted June 30, 2017 On 6/28/2017 at 8:37 AM, Kryten said: Many vehicles already re-enter intact without a braking burn; CZ-2 first stages have been documented doing so, and according to ULA the atlas 5 first stage does. Falcon isn't tough enough to do it because of it's extreme mass ratio, but it doesn't seem all that hard in practice. Looking at some of those "look at how big this rocket is" charts, I'm guessing New Glen has the longest first stage booster. Assuming drag of a cylinder scales with length, it should be the most aerodynamic (least drag) booster out there. This should make slowing down more difficult, but I'd expect it stages so the thing gets to fly horizontally through the atmosphere far enough (and high enough) to replace the braking burn. I'm not sure whether these are giant steps, or simply building to a different scale is mostly a matter of money. Quote Link to comment Share on other sites More sharing options...
NSEP Posted June 30, 2017 Share Posted June 30, 2017 Im running up RSS/RO now and im making some BO rockets. I have seen a BE-4 in the part list, so i could do it. I do not think BO should be compared to SpX in my opinion. Quote Link to comment Share on other sites More sharing options...
sevenperforce Posted June 30, 2017 Share Posted June 30, 2017 1 hour ago, NSEP said: I do not think BO should be compared to SpX in my opinion. Perhaps not, but comparisons between the flight profiles of the Falcon 9 and the New Glenn seem spectacularly on-point. Quote Link to comment Share on other sites More sharing options...
tater Posted July 3, 2017 Share Posted July 3, 2017 Quote Link to comment Share on other sites More sharing options...
Nightside Posted July 4, 2017 Share Posted July 4, 2017 On 6/30/2017 at 11:06 AM, NSEP said: I do not think BO should be compared to SpX in my opinion. Indeed comparisons are odious. But why not compare privately owned rocket companies building methalox engines? There is little else to compare them to... Quote Link to comment Share on other sites More sharing options...
NSEP Posted July 4, 2017 Share Posted July 4, 2017 1 hour ago, Nightside said: Indeed comparisons are odious. But why not compare privately owned rocket companies building methalox engines? There is little else to compare them to... Yeah, that could be compared to eachother. If only i knew the ISP of the BE-4... Quote Link to comment Share on other sites More sharing options...
Hannu2 Posted July 4, 2017 Share Posted July 4, 2017 On 30.6.2017 at 9:06 PM, NSEP said: I do not think BO should be compared to SpX in my opinion. Why not? They are new innovative companies which work at same markets. They will very probably be hard competitors after few years. Of course oversimplifications like one is good and another is bad because some small technical detail are stupid comparisons, but technical choices, success of missions, economic success, possible new breakthroughs etc. will be very interesting to compare with each other when Blue Origin achieves commercial operations. Quote Link to comment Share on other sites More sharing options...
NSEP Posted July 4, 2017 Share Posted July 4, 2017 4 minutes ago, Hannu2 said: Why not? They are new innovative companies which work at same markets. They will very probably be hard competitors after few years. Of course oversimplifications like one is good and another is bad because some small technical detail are stupid comparisons, but technical choices, success of missions, economic success, possible new breakthroughs etc. will be very interesting to compare with each other when Blue Origin achieves commercial operations. Yeah, i agree. But i will only compare their future plans. When New Glenn starts flying ill start talking. Quote Link to comment Share on other sites More sharing options...
tater Posted July 20, 2017 Share Posted July 20, 2017 Quote Link to comment Share on other sites More sharing options...
MaverickSawyer Posted July 20, 2017 Share Posted July 20, 2017 On 6/26/2017 at 2:00 PM, magnemoe said: Why the color / steel finish difference? Front has an huge flange halfway down Those are Thrust Chamber Assemblies (TCA's) 1, 2, and 3, from right to left. The flange is a handling fixture, and is used for maneuvering the TCA around the shop. The difference in colors is due to the TCAs being at different phases of manufacturing. The darker colored ones (TCAs 2 and 3) are not yet lathed, while the shiny one (TCA 1) is just waiting on a useable powerpack to commence full-up hotfire tests. Regarding the announcement of the plant in Huntsville, that's ONLY if they win the contract with ULA for Vulcan. Scuttlebutt I've heard has that as a given, as ULA has designed Vulcan for methane/LOx tankage, not LOx/RP-1 as used in the AR-1 engine. On 7/3/2017 at 11:06 PM, NSEP said: Yeah, that could be compared to eachother. If only i knew the ISP of the BE-4... BE-4: ~320s sl, ~350s vac BE-4U: ~370-390s vac. Quote Link to comment Share on other sites More sharing options...
Streetwind Posted July 21, 2017 Share Posted July 21, 2017 16 hours ago, MaverickSawyer said: as ULA has designed Vulcan for methane/LOx tankage, not LOx/RP-1 as used in the AR-1 engine. They actually developed both, and keep carrying along both to this day. Which is also a part why Tory Bruno is anxious to make a selection soon. He wants to be able to cancel one of the two. While it's only a partial cost increase, not a straight doubling, it's still an unnecessary expense. Quote Link to comment Share on other sites More sharing options...
Kryten Posted July 21, 2017 Share Posted July 21, 2017 40 minutes ago, Streetwind said: They actually developed both, and keep carrying along both to this day. Which is also a part why Tory Bruno is anxious to make a selection soon. He wants to be able to cancel one of the two. While it's only a partial cost increase, not a straight doubling, it's still an unnecessary expense. The CDR assumed the methalox version. The kerolox is in dev, to an extent, but it's clearly getting nowhere near the resources of the methalox version. Hell, have ULA even released an official image of the kerolox version? Quote Link to comment Share on other sites More sharing options...
Streetwind Posted July 21, 2017 Share Posted July 21, 2017 Not to my knowledge. And by this point, it looks like we never will... Quote Link to comment Share on other sites More sharing options...
tater Posted July 21, 2017 Share Posted July 21, 2017 Quote Bezos' visionary scenario is being held back by a central issue, he said. "Space travel is just too darn expensive. And we know why it's too expensive. It's because we throw the rockets away," Bezos explained. "We're never going on to do these grand things and to expand into the solar system as long as we throw this hardware away. We need to build reusable rockets, and that is what Blue Origin is dedicated to … taking my Amazon lottery winnings and dedicating to … it's a passion, but it's also important." https://www.space.com/37572-jeff-bezos-trillion-people-solar-system.html Quote Link to comment Share on other sites More sharing options...
MaverickSawyer Posted July 21, 2017 Share Posted July 21, 2017 4 hours ago, Kryten said: The CDR assumed the methalox version. The kerolox is in dev, to an extent, but it's clearly getting nowhere near the resources of the methalox version. Hell, have ULA even released an official image of the kerolox version? Agreed. ULA has deliberately been slow-rolling the kerolox version, reportedly with only a handful of engineers, while metholox received full attention. Quote Link to comment Share on other sites More sharing options...
kerbiloid Posted July 24, 2017 Share Posted July 24, 2017 (edited) On 21.07.2017 at 4:06 PM, tater said: "Space travel is just too darn expensive. And we know why it's too expensive. It's because we throw the rockets away It's expensive because a system to carry random civilians, not chosen hotshots, has to be much more reliable than 1:70 chances to die. This has no relation to the reusability at all. Rocket is cheap, responsibility is expensive. Edited July 24, 2017 by kerbiloid Quote Link to comment Share on other sites More sharing options...
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