Monday, January 4, 2016

Follow Up on Last Month's SpaceX Launch and Reusing the Booster

Four days before Christmas, SpaceX launched a mission that seems to have swapped its primary and secondary missions!  The primary mission was to send a fleet of 11 satellites into space for a paying customer, but what everyone is talking about is the secondary mission: how they returned the Falcon9 booster from the edge of space, and landed it dead center on a landing pad a few miles from the launch site.

At the time, Elon Musk said that this one wouldn't be re-used, but studied.  In my opinion, that was the right answer.  Look it over carefully and make sure that there's nothing latent in that booster that would make a second flight much riskier than it should be.  Use it as an engineering test vehicle.  There's virtually no down side: if they find something that requires an engineering change to the booster, they'll improve its reliability and make it better.  If they take it apart and find nothing questionable at all, at the worst case, they've just written off a vehicle that could have not made the landing.
Ars Technica posts this picture - along with several more - of the booster in SpaceX's hanger, noting that the booster has a "sooty" look but is apparently undamaged.  Aside from soot, produced by the kerosene fuel used in the rocket's engines, the Falcon 9 booster appears to be fine.
That was the assessment of SpaceX founder Elon Musk, who tweeted, "No damage found, ready to fire again," on New Year's Eve. Musk has said the flown booster will undergo "static fire" testing on the launch pad, in which the rocket is restrained while its engines are fired. After testing, the rocket is expected to become a valued artifact, although Musk has not said where its final resting place will be.

During a conference call with reporters after the launch and successful recovery of the Falcon 9 rocket on December 21, Musk said he expects the company will attempt to refly a Falcon 9 rocket sometime in 2016.
They're going to have to start naming those rockets, like the shuttles were, or most every other ship.  She looks a bit like a used spaceship now.  That's only going to get worse with more reuse and more confusing if they have several in the process of being refurbished for reuse.  If it is just soot, essentially hydrocarbon ash, a good car wash could be all she needs.  A very big car wash.


  1. So frigging cool. Rockets landing nose-up, as God and R. A. Heinlein intended! I wonder if this particular booster will end up in the Smithsonian. They should consider naming them "Heinlein"s or "Pournelle"s...Prometheus would work too, I suppose. :-P I mean "Saturn" is cool, but these things might've popped right out of a "Medship Man" (Murray Leinster) story! Awesome.

    1. In the early 90s, I had the chance to work on the "Delta Clipper" or DC-X concept test vehicle. Only on the electronics package at one of the subcontractors. But it was neat to work on a rocket that took off and landed on its tail, even if they were short flights.

      The initial goal was SSTO - single stage to orbit - and it never got there. That's something that hasn't been done, yet, that I can think of. More details at that Wiki page than I remembered, by far.

    2. Look up Venture Star to see why SSTO doesn't work. LockMart intended to build and operate it. Until they realized near PDR that the payload capability to orbit was around -5000 pounds. And do note that sign carefully. The vehicle was that short of being able to reach orbit WITHOUT any payload. At PDR. I suspect you are aware of what happens to vehicle design performance between PDR and operational flight...

  2. Jerry Pournelle disagrees with you, Mark, though I understand why you feel the way you do. I'd recommend reading his papers on the subject...they're absolutely fascinating. SSTO isn't *easy* by any stretch of the imagination, but it *is* possible. :-D