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Topic: [Discuss] SpaceX Falcon 9 v1.1/CASSIOPE launch
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Robert Pearlman Editor Posts: 42988 From: Houston, TX Registered: Nov 1999
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posted 08-29-2013 07:55 PM
Editor's note: In an effort to keep the topic SpaceX Falcon 9 v1.1/CASSIOPE from SLC-4E focused on status updates, reader's feedback and opinions are directed to this thread. Please use this topic to discuss SpaceX's maiden launch from Vandenberg Air Force Base's Space Launch Complex 4E using the company's first Falcon 9 v1.1 rocket. |
SkyMan1958 Member Posts: 867 From: CA. Registered: Jan 2011
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posted 08-29-2013 11:23 PM
Re-usable stages would be a MAJOR step forward in lowering costs. Obviously this is but the first test, and many more will need to be made. I guess one question I've been wondering about for a while is, given the major US launching sites, where would a land touchdown occur? I guess with Vandenberg you could potentially land somewhere along the western coast of a North or South American country, but launching from KSC most likely your booster would land in the drink. |
Robert Pearlman Editor Posts: 42988 From: Houston, TX Registered: Nov 1999
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posted 08-29-2013 11:48 PM
SpaceX's design is for a flyback booster that lands vertically on legs. Earlier animations released by the company suggest the stages — and eventually Dragon itself — would come to land on a runway, such as the Skid Strip at the Cape Canaveral Air Force Station or Shuttle Landing Facility at Kennedy Space Center. |
GACspaceguy Member Posts: 2476 From: Guyton, GA Registered: Jan 2006
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posted 08-30-2013 09:59 AM
I am sure they have to work out range safety issues and contingency sites, as well as weather constraints. My question I ponder is how much return fuel each stage would need to carry and how does that impact the economics of its reusability.
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gliderpilotuk Member Posts: 3398 From: London, UK Registered: Feb 2002
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posted 08-31-2013 04:16 PM
Same (unanswered) question I posed about Grasshopper. It's not just the extra fuel for landing, but the extra launch fuel required to launch the extra landing fuel! It's a great concept but on the face of it one where risk (versus a parachute or runway landing) and cost efficiency seem sacrificed for convenience (of landing location). Will they carry a backup parachute system? It would also be interesting to see the costs of vehicle refurb versus new build. |
Robert Pearlman Editor Posts: 42988 From: Houston, TX Registered: Nov 1999
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posted 08-31-2013 04:34 PM
Elon Musk and the engineers at SpaceX are intelligent individuals. I doubt they would undertake such a venture if they didn't feel it would result in reduced costs and increased efficiency. They are a commercial company however, so I don't expect them to lay out all the particulars so their competition can follow suit. |
GACspaceguy Member Posts: 2476 From: Guyton, GA Registered: Jan 2006
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posted 08-31-2013 07:29 PM
quote: Originally posted by Robert Pearlman: Elon Musk and the engineers at SpaceX are intelligent individuals.
Absolutely agree, I would just love to see the data on how the system works and how it pays back. It has never been done before and the details of how it will work out are interesting me.Agree with the proprietary nature of the details though, as I deal with those rules everyday myself. |
Robert Pearlman Editor Posts: 42988 From: Houston, TX Registered: Nov 1999
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posted 08-31-2013 08:10 PM
I think more details will be shared as SpaceX moves closer to a first stage land recovery. I would certainly expect the media to press for more details, especially if the system is put into place for NASA-sponsored flights. |
Robert Pearlman Editor Posts: 42988 From: Houston, TX Registered: Nov 1999
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posted 09-06-2013 08:12 PM
Space News spoke with Elon Musk about the upcoming flight. Privately owned SpaceX planned to conduct a static-test firing of the rocket's new Merlin 1D engines the weekend of Sept. 7-8, the last major hurdle before a launch attempt could be made as early as a week or two later, founder and chief executive Elon Musk told SpaceNews. At press time, a NASA manifest had the launch slated for Sept. 14."We're being, as usual, extremely paranoid about the launch and trying to do everything we possibly can to improve the probability of success, but this is a new version of Falcon 9," Musk said. With regards to the "soft" water landing... "Just before we hit the ocean, we're going to relight the engine and see if we can mitigate the landing velocity to the point where the stage could potentially be recovered, but I give this maybe a 10 percent chance of success," Musk said. In a related program called Grasshopper, SpaceX has been developing a booster stage that can fly itself back to a launch pad. "We've never attempted to land Grasshopper on water. We don't know if the radar system will detect the water surface level accurately. We don't know all sorts of things, so I really give it a very tiny chance of success. But we're going to see what data we can learn," Musk said. |
Robert Pearlman Editor Posts: 42988 From: Houston, TX Registered: Nov 1999
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posted 09-29-2013 04:23 AM
Per SpaceX: September 29th, the upgraded Falcon 9 rocket will launch a demonstration mission from Vandenberg Air Force Base. The launch window opens at 9:00 a.m. PDT. The launch will be webcast beginning at approximately 8:15 a.m. PDT at spacex.com/webcast. A press kit for the flight can be found here. |
Joel Katzowitz Member Posts: 808 From: Marietta GA USA Registered: Dec 1999
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posted 09-29-2013 03:00 PM
I was at SpaceX headquarters in Hawthorne CA on Thursday for a meeting. The buzz throughout the building in anticipation of today's launch was amazing. Everyone who works there feels it's their vehicle, their mission. What an exciting and inspiring place to visit. |
Robert Pearlman Editor Posts: 42988 From: Houston, TX Registered: Nov 1999
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posted 09-29-2013 03:52 PM
Though the recovery of the first stage did not go as planned, they were able to recover several parts. "I heard that they were able to recover the interstage and a number of components from the engine bay and some of the composite overwrapped pressure vessels," [SpaceX founder and CEO Elon] Musk told reporters in a telecon following the flight. "That's all I know at this point, there may be more." I have inquired with SpaceX what the intentions are with those parts, whether they may be reused (if in serviceable shape) or will be kept as engineering or display units. |
Jim Behling Member Posts: 1463 From: Cape Canaveral, FL Registered: Mar 2010
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posted 09-29-2013 07:35 PM
quote: Originally posted by Joel Katzowitz: What an exciting and inspiring place to visit.
No different than other companies that fly space hardware. |
Robert Pearlman Editor Posts: 42988 From: Houston, TX Registered: Nov 1999
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posted 09-30-2013 08:20 AM
quote: Originally posted by GACspaceguy: I am sure they have to work out range safety issues and contingency sites, as well as weather constraints.
Elon Musk briefly addressed range safety during a post-launch media telecon on Sunday (Sept. 29) afternoon. He said that SpaceX has been working with the Eastern Range and that they have chosen a remote site at Cape Canaveral (Musk didn't want to disclose the site yet). SpaceX's next attempt at recovering the first stage will be on their third commercial resupply launch to the space station, currently slated for February. quote: I ponder is how much return fuel each stage would need to carry and how does that impact the economics of its reusability.
Musk said for a water landing payload capability is reduced by 15 percent; by 30 percent for a land touchdown. |
GACspaceguy Member Posts: 2476 From: Guyton, GA Registered: Jan 2006
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posted 09-30-2013 07:46 PM
Thanks for the info update Robert. The concept is great and the fuel tradeoff is less than I thought it may be for the land touchdown. |
Glint Member Posts: 1040 From: New Windsor, Maryland USA Registered: Jan 2004
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posted 10-02-2013 12:02 PM
SpaceX seems to be vigorously denying an explosion of the Falcoln 9 second stage following separation of its multiple payloads. This is being reported in a number of places, including Aviation Week.Seems that radar data reviewed by SpaceTrack.org revealed an unually large debris field along the orbital path leading to speculation that the second stage had unexpectedly disintegrated or even exploded. SpaceX denies any explosion occurred and is blaming it on a scenario in which "possible insulation came off." Here's a pseudo random link, from Business Insider (of all places), that provides statements from both sides. |
Robert Pearlman Editor Posts: 42988 From: Houston, TX Registered: Nov 1999
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posted 10-02-2013 12:20 PM
Here is SpaceX's statement, in its entirety: Following separation of the satellites to their correct orbit, the Falcon 9 second stage underwent a controlled venting of propellants (fuel and pressure were released from the tank) and the stage was successfully safed. During this process, it is possible insulation came off the fuel dome on the second stage and is the source of what some observers incorrectly interpreted as a rupture in the second stage. This material would be in several pieces and be reflective in the Space Track radar. It is also possible the debris came from the student satellite separation mechanisms onboard.SpaceX will continue to review to help identify the source of the extra debris, but our data confirms there was no rupture of any kind on the second stage. |
Glint Member Posts: 1040 From: New Windsor, Maryland USA Registered: Jan 2004
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posted 10-02-2013 12:52 PM
SpaceX has made multiple statements regarding the debris field in the vicinity of the orbital track. In a couple of them Elon Musk comes off as appearing guilty of invoking the shooting the messenger fallacy: - Concerning the story being posted on the international Russian space blog Zarya, "The Russians are our main competitors, so I would take what they say with a grain of salt."
- Belittling the observations from SpaceTrack.com: "...we do know it's common that the first measurements from Space-Track are not very accurate and sometimes mixed up ... usually takes a few days for them to sort it all out..."
Even if these views have some validity, it's unbecoming. |
Robert Pearlman Editor Posts: 42988 From: Houston, TX Registered: Nov 1999
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posted 10-02-2013 01:04 PM
Musk was forthcoming on the post-launch media telecon, openly admitting to what went wrong on the flight and in some detail. I don't see any reason he would switch tactics and lie about the second stage, when he had already disclosed the planned second burn was aborted. |
Glint Member Posts: 1040 From: New Windsor, Maryland USA Registered: Jan 2004
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posted 10-02-2013 01:26 PM
I'm not convinced that Musk has been all that forthcoming. His statment that "the Falcon 9 second stage underwent a controlled venting of propellants (fuel and pressure were released from the tank) and the stage was successfully safed" has overlooked the fact that this safing activity may have been necessary as a result of the failure of a mission objective.Following release of the payloads, the second stage was supposed to be reignited, but failed. So it wasn't really as routine as Musk tries to make it sound by glossing over this anomaly. The restartable engine is supposed to be a selling feature for the Falcoln 9. In this article, "SES is awaiting a detailed explanation from SpaceX as to why the second stage of its upgraded Falcon 9 booster failed to reignite during a flight on Sunday." Looks like SpaceX has some explaining to do whether or not the second stage exploded. |
Robert Pearlman Editor Posts: 42988 From: Houston, TX Registered: Nov 1999
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posted 10-02-2013 01:52 PM
Musk said hours after the launch that his engineers believed they knew the cause of the second stage's failure to re-light and knew how to correct for it. It would be a matter of course that SpaceX would brief SES before their launch. There is nothing unusual with SES requesting a technical description of what went wrong, nor does it in any way suggest Musk has anything to hide. |
Robert Pearlman Editor Posts: 42988 From: Houston, TX Registered: Nov 1999
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posted 10-15-2013 07:34 PM
From SpaceX's mission summary released today (see the update topic for the full statement): Following separation of the last payload, SpaceX attempted an internal milestone of relighting the second stage. Conditions appeared satisfactory for relight of the upper stage engine as the stage flew over Antarctica. The engine initiated ignition, with pressure rising in the thrust chamber to about 400 psi, but the flight computer sensed conditions did not meet criteria and it aborted the ignition. SpaceX believes it understands the issue which didn’t involve anything fundamental, rather a need to iron out some of the differences between operating the engine on the ground versus in a vacuum. SpaceX has actually relit the Merlin engine in ground testing a dozen times in some cases and SpaceX is confident it can make the necessary adjustments before the next flight. Despite reports to the contrary, the Falcon 9 second stage remained intact and healthy following spacecraft separation. It takes a few days to get the data from the Air Force Satellite Control Network into the SpaceX data system for review, but the data confirms the stage passed over Hawaii from approximately 1748 to 1754 Universal Time (10:48-10:54 PDT), roughly 1 hr 48 minutes after launch, starting into our second orbit. SpaceX still had power on the second stage, and the transmitters were left on to drain the batteries (standard procedure). |