Quote from: Robotbeat on 03/08/2013 10:36 pmA reusable vehicle is much cheaper to test...I'm still having trouble seeing how reuse could pay off. We saw last year that a Merlin fired one too many times, with a test history just slightly longer than other flown engines, blew itself apart. How many of these recovered engines could actually be reused? - Ed Kyle
A reusable vehicle is much cheaper to test...
Quote from: edkyle99 on 03/09/2013 02:59 amQuote from: Robotbeat on 03/08/2013 10:36 pmA reusable vehicle is much cheaper to test...I'm still having trouble seeing how reuse could pay off. We saw last year that a Merlin fired one too many times, with a test history just slightly longer than other flown engines, blew itself apart. How many of these recovered engines could actually be reused? - Ed KyleI find it in bad taste and unprofessional to allege that SpaceX's statements are intentionally misleading. This goes back to the "sudden pressure release" - there was a lot of bad-natured talk about how SpaceX was practically hiding the true nature of the incident, talk that was absolutely baseless.But they have never, to my recollection, mis-characterized any of their failures.
Quote from: meekGee on 03/09/2013 04:48 amQuote from: edkyle99 on 03/09/2013 02:59 amQuote from: Robotbeat on 03/08/2013 10:36 pmA reusable vehicle is much cheaper to test...I'm still having trouble seeing how reuse could pay off. We saw last year that a Merlin fired one too many times, with a test history just slightly longer than other flown engines, blew itself apart. How many of these recovered engines could actually be reused? - Ed KyleI find it in bad taste and unprofessional to allege that SpaceX's statements are intentionally misleading. This goes back to the "sudden pressure release" - there was a lot of bad-natured talk about how SpaceX was practically hiding the true nature of the incident, talk that was absolutely baseless.But they have never, to my recollection, mis-characterized any of their failures.Suing Joe Fragola for making what SpaceX claimed were defamatory allegations about the safety and reliability of SpaceX’s Falcon 9 rocket left a lot of folks with a bad taste in their mouths. And "oxidizer-rich shutdown" was another. I would say that Elon is his own worst enemy, but that is more likely reserved for Sen. Shelby. Openly criticizing Shelby was a very immature thing to do.
ChrisWhoever loves correction loves knowledge, but he who hates reproof is stupid."Sorry to say it, but if your interest in space is only the launch piece then you aren't interested in space, just big fireworks." --Michael Mealling
Even now, you choose to go with "blew itself apart", whereas from what we're hearing it was a rapture of the jacket over the cooling channels, which would have resulted in basically a high-pressure diffuse spray of fuel,
Returning to the topic of putative ocean landing attempt of V1.1 first stage on it's maiden flight.I've been wondering about the properties of a water landing. Assuming a vertical "stick" landing will water approximate a solid surface or will there be a large "bowl" blown in the surface by the exhaust? Also, how much boiling will occur and which way will the steam have to go and what will it do to the stage. Finally, anyone have a good speculation about what contact with cold water will do to the engines?
Quote from: mr. mark on 03/08/2013 04:04 pmSo in essence we are go for next launch first stage turnaround and attempted slow down. Wow! So quick. I thought the process would take years.The plan for the v1.1 version of F9 to do a retroburn and try a vertical drop of the stage directly down was reported here by KSC Sage a long time ago. So long that most people (including me) seem to have forgot about it since.
So in essence we are go for next launch first stage turnaround and attempted slow down. Wow! So quick. I thought the process would take years.
Based on noises from SpaceX about mass production, it certainly sounds like they are trying to settle on the v1.1 and mass produce that. (using lessons learned from F9v1.0)
It's not supposed to reused after the water landing, just prove that it can impact the ocean in one piece (something v1.0 never did). The killer is side loads, so they have to prove they can orient the vehicle tail first before the rest of the recovery sequence can work. If they do a relight and softly land in the water, great, but that's nothing Grasshopper can't do.
I've been told that the v1.1 will become SpaceX's "workhorse" launch vehicle. SpaceX has told NASA they plan on producing up to 40 v1.1 cores/boosters a year for the F9 and F-H vehicles.
...Assuming a vertical "stick" landing will water approximate a solid surface or will there be a large "bowl" blown in the surface by the exhaust?
Also, how much boiling will occur and which way will the steam have to go and what will it do to the stage.
Finally, anyone have a good speculation about what contact with cold water will do to the engines?
Quote from: KSC Sage on 03/09/2013 03:29 pmI've been told that the v1.1 will become SpaceX's "workhorse" launch vehicle. SpaceX has told NASA they plan on producing up to 40 v1.1 cores/boosters a year for the F9 and F-H vehicles.That was a given
It will displace some water - proportionally to the engine thrust, but not 100%. So, just before "touchdown" there should be a bowl of about several dozens cubic meters volume, I'd love to see that