Total Members Voted: 504
Quote from: vaporcobra on 10/22/2017 07:44 pmQuote from: JamesH65 on 10/22/2017 07:36 pmTo me it just sounds like actual rocket engineers being cheesed off that they've been told what's what by armchair rocket engineers.I fully agree that I am a complete non-expert in comparison to actual propulsion engineers, but that doesn't excuse the highly irrational and arrogant attitude towards Raptor. Even if scaling thrust by ~70% is far more difficult than SpaceX's RPS engineers believe it to be, almost completely discounting 1200 seconds of hot-fires, half a decade of Merlin 1D mass production, and orbital and vacuum rocketry experience fly directly counter to the ideals a functional and rational engineer/scientist ought to hold. and FWIW, I did not start the discourse. The trash talking was begun unsolicited by a BO propulsion engineer.I don't know if you really understand what he's saying:What he's saying is that the Blue Origin engine is full size ... Combustion Chamber, injectors, preburner injectors, pumps, everything is full size, that requires no drawing changes (in theory) when they go to flight, full thrust SHOULD be as easy as opening up the fuel valve to the preburner to let the turbopump spin faster... i don't know if this is what they're using to alter pump speed (inevitably engine power level) or not... whether this happens or not is yet to be seenSpaceX's Raptor is: what, help me out here ... 80% geometrically the size of the flight engine size, this means new part numbers for the combustion chamber, injector, preburner(s) injectors, pumps, if i'm understanding what Elon has said correctly, everything has to be geometrically scaled up to reach flight engine size, that is not a small task, also, dynamic similitude in fluid mechanics doesn't mean you multiply or divide everything by 0.80 ...^ my $0.02C
Quote from: JamesH65 on 10/22/2017 07:36 pmTo me it just sounds like actual rocket engineers being cheesed off that they've been told what's what by armchair rocket engineers.I fully agree that I am a complete non-expert in comparison to actual propulsion engineers, but that doesn't excuse the highly irrational and arrogant attitude towards Raptor. Even if scaling thrust by ~70% is far more difficult than SpaceX's RPS engineers believe it to be, almost completely discounting 1200 seconds of hot-fires, half a decade of Merlin 1D mass production, and orbital and vacuum rocketry experience fly directly counter to the ideals a functional and rational engineer/scientist ought to hold. and FWIW, I did not start the discourse. The trash talking was begun unsolicited by a BO propulsion engineer.
To me it just sounds like actual rocket engineers being cheesed off that they've been told what's what by armchair rocket engineers.
Between SX and BO, the former has launched multi-engine, multi-stage rockets to LEO. And while SX has developed almost all the key elements for BFR/BFS into LEO [excluding the refuel maneuver for other uses] in some form or other, BO has done little. Maybe BO can compete with SLS ME2, maybe they will all be close when the combusted fuel hit the launch pad, maybe they will spread over many years, maybe some will fail. But Berger is out on a fishing expediting for bad analysis.
I think Blue will be able to compete eventually. I just think SpaceX is ahead with BFR.
I tell ya, if ULA start flying a vehicle with a Raptor engine I'm going to have to go buy some new ice skates.
Does the new money the Air Force possibly invest in Raptor mean SX can progress faster?
I bet BFS will get to space before New Glenn or Vulcan or Ariane 6 or SLS.
Quote from: Kansan52 on 10/23/2017 02:49 amDoes the new money the Air Force possibly invest in Raptor mean SX can progress faster?Only if they were ressource constrained before. Otherwise I would go with the old adage: Throwing manpower at a late project makes it later.
FWIW, I expect we'll see full scale testing begin before the end of 2017.
Quote from: vaporcobra on 10/23/2017 05:49 amFWIW, I expect we'll see full scale testing begin before the end of 2017.If they had a full-scale engine almost ready for testing I expect Musk would have shown off some pictures of full-scale hardware at IAC. The fact that he didn't might suggest that they are still a ways off.FWIW, I wouldn't be surprised if we didn't see a full scale Raptor test fire until late 2018 or even 2019. These things take time.
Quote from: Robotbeat on 10/22/2017 09:29 pmI bet BFS will get to space before New Glenn or Vulcan or Ariane 6 or SLS.Unmanned SLS will get there first. Then you'll see manned BFS on Luna and SLS will never fly again.Most likely none of those others will ever fly again. Why sail galleons when container ships suddenly show up?
Although Raptor will help revolutionize access to space it will not cause the death of all other (new) launch systems. For example: Ariane 6 will fly, and after it a next generation Ariane vehicle will as well. The reason is simple: Europe wants it's own independently assured access to space.
Quote from: Robotbeat on 10/22/2017 09:29 pmI bet BFS will get to space before New Glenn or Vulcan or Ariane 6 or SLS.Unmanned SLS will get there first. Then you'll see manned BFS on Luna and SLS will never fly again.
Robotbeat said BFS going to space. Which would be an early test flight of the SSTO kind. I fully expect that to happen in 2019 or early 2020. It may very well be BFS first. Though for the full stack I agree. It will likely be SLS.
Although Raptor will help revolutionize access to space it will not cause the death of all other (new) launch systems. For example: Ariane 6 will fly, and after it a next generation Ariane vehicle will as well. The reason is simple: Europe wants it's own independently assured access to space. When the original Ariane vehicle was being developed there was a lot of pressure from the United States to stop that development. The thinking was that Europe could get all the launch services they ever needed by buying them from the United States. Europe developed Ariane regardless, despite that seeming to be the more expensive option. The same applies to China.So, once BFR/BFS is flying, there will still be vehicles such as Ariane 6 and Long March (insert a number here).
...I think very true, other nations will not cede space to SpaceX, they will invest what is needed to catch up. That is the really exciting time. Landing on mars is not as fundamental a milestone to me as the moment we see China test their first grasshopper, and the age of reusable rockets is here no matter how badly SpaceX may stuff up in any future endeavour.
Quote from: guckyfan on 10/23/2017 07:57 amRobotbeat said BFS going to space. Which would be an early test flight of the SSTO kind. I fully expect that to happen in 2019 or early 2020. It may very well be BFS first. Though for the full stack I agree. It will likely be SLS.I think that's optimistic. I am confident BFR/RFS are going to succeed, but let's remember, SX hasn't even put a manned Dragon into orbit yet.
Quote from: guckyfan on 10/23/2017 07:57 amRobotbeat said BFS going to space. Which would be an early test flight of the SSTO kind. I fully expect that to happen in 2019 or early 2020. It may very well be BFS first. Though for the full stack I agree. It will likely be SLS.I suspect Elon means sub-orbital flight testing, with the first orbital flights not happening until they've ironed out the kinks.