At the risk of becoming a space blogger — really it’s just a healthy interest — I wanted to link to this as a good example of clarity and corporate communication. No matter what spin SpaceX put on the launch from the other week, the media focused on the rocket’s failure. Inevitably so, perhaps. In the news, nothing succeeds like failure.
I’m no pollyanna, but I’m cheering for SpaceX. Just on principle, if anything.
Still, you have to hand it to Musk for writing up (or at least having written in his name) this report and posting it so quickly. The launch was only just a few days ago, yet they’re willing make public their preliminary findings. Maybe it is from desperation, but it also seems like good communications strategy.
Musk writes in friendly, open tones. There are lot of technical details, but they are explained well and he uses some reasonably good analogies.
Take, for example, the discussion of why the rocket’s second stage failed — after a few minutes, when the amount of liquid oxygen fuel started to get low, the fuel sloshed around too much for the fuel pump to capture. The momentum from the sloshing, as near as I can tell (IANRS*), caused the second stage to start wobbling like an unbalanced washing machine. Duh, why am I telling you this, here’s the quote:
n a nutshell, the data shows that the increasing oscillation of the second stage was likely due to the slosh frequency in the liquid oxygen (LOX) tank coupling with the thrust vector control (engine steering) system. This started out as a pitch-yaw movement and then transitioned into a corkscrewing motion. For those that aren’t engineers, imagine holding a bowl of soup and moving it from side to side with small movements, until the entire soup mass is shifting dramatically. Our simulations prior to flight had led us to believe that the control system would be able to damp out slosh, however we had not accounted for the perturbations of a contact on the stage during separation, followed by a hard slew to get back on track.
The solution, it appears, is to design better “slosh baffles” to prevent the fuel from bouncing about. I hope it works.
In the second portion, he gets a bit defensive, but perhaps rightfully so given the press he’s received regarding the launch.
Here, he gets a bit close to protesting too much, but saves it just short of whining:
This is not “spin” or some clever marketing trick, nor is this distinction an invention of SpaceX — it has existed for decades. The US Air Force made the same distinction a few years ago with the demonstration flight of the Delta IV Heavy, which also carried no primary satellite. Although the Delta IV Heavy fell materially short of its target velocity and released its secondary satellites into an abnormally low altitude, causing reentry in less than one orbit, it was still correctly regarded by Boeing and the Air Force as a successful test launch, because sufficient data was obtained to transition to an operational phase.
Lastly, while I like the images, it would have been nice to have a little more context. What’s the significance, for example, of having the nozzle high above the horizon? If there is none, why mention it?
Anyway, next Falcon 1 launch is at the end of the summer. This time, they plan an actual operational mission, so we’ll see how it goes.
*I Am No Rocket Scientist