On 10/6/2013 7:36 PM, Henry Spencer wrote:
On Sun, 6 Oct 2013, Henry Vanderbilt wrote:I hadn't known about the specific limit on Merlin starter cartridges though. A quick search didn't turn anything up. Any idea where to find out more about that?Don't remember where I saw it discussed, alas, and a quick search doesn't find anything... The Falcon 9 User's Manual (rev 1, 2009) credits the second stage with "2 restarts" capability, which might have been what I was remembering (although the most plausible reading of that wording would give it a total of 3 starts, not 2).
And there's no guarantee that hasn't changed with the new upper-stage engine and other redesign, of course. But in general, multiple restart capability makes a lot of sense for such a stage, providing for more flexibility for complex missions, and more redundancy for simple ones.
In any event, that does make it seem very unlikely that the restart test was abandoned after one try because the hardware only provided for one try. Presumably something made it immediately obvious that more restart attempts would be futile.
Given that SpaceX has customers both current and prospective to reassure, I expect more detail about what happened and what they do about it will eventually come out.
Henry
