SpaceX Falcon boosts to glory from Vandenberg space force base Internet zillionaire Elon Musk has carried out a successful test of his Falcon rocket, launching from the US military space-plex at California's Vandenberg airforce base even as the delayed Cygnus capsule from rival private-space contender Orbital Sciences overcame a software glitch to successfully dock with the International …
Note that this is the first F9 v1.1 with the lengthened tanks and high T/W ratio engines in the new 8-ring-n-1-in-centre layout than the old 3x3.
This was also a CCiCAP milestone as this is version that will carry the crewed Dragon. A flawless 1st flight for this is very good news for Spacex's chances of getting the crew contract for the ISS.
Too bad the secondary objective of a "soft" touchdown for the 1st stage didn't work out. The first firing to slow the booster went well, but the second firing put the 1st stage into a spin/crash. Also the other secondary objective to re-light the second stage didn't work, but the engineers say they have a fix for that problem.
The secondary objective wasn't exactly a soft touchdown of the 1st stage - it was to run tests on the basic soft touchdown ability to learn how far they still had to go. It was expected to "fail" but to teach Space X enough to get closer to a soft touchdown with each test.
As far as I could tell, the objective was to do a soft touchdown, but over water, rather than land, which I thought was a bit harsh to the computer doing the landing:
"Here we go, successfully de-accelerated, everything worked perfectly, ready to touchdown.."
*SPLASH*
"What did I do wrong?" *GLUB GLUB*
Apparently though the spinning caused the fuel to centrifuge to the outside of the tanks, cutting off the flow to the engine. Oh well, better luck next time folks.
Any success is good, so both companies did well.
Despite the massive redundancy and pre-flight preparation there is always the chance of a glitch and considering both of these vehicles are still in development they did well.
Although SpaceX has a bigger vehicle there is no reason why Cygnus should not be successful as well depending on the mission bigger is not always better when the main cost of the mission is getting mass up out of a gravity well.
Anything that helps to move humanity as a race into space gets my vote!
The video from the SpaceX launch is not published yet, but I'll link you in here.
Sounds like the Grasshopper landing test achieved some goals, the engine was reignited twice, but did also suffer a flame out. no vid of soft landing test... not sure if there will be either.. but would be good to see some data maybe a graph or two...
According to Musk, aerodynamic roll was induced during descent, that got too fast and spun the fuel away from the engines, causing them to flame out through lack of fuel. But the fact they did reignite at supersonic speeds is quite impressive. He reckons they should have reused an F9 first stage by end of next year (which implies recovering it intact.)
15% decrease in payload for water landing, 30% for land. Seems a good tradeoff to save $40-50M and 9 engines.
If you're going to be really nit-picking, orbit wouldn't work if they didn't weigh anything. It is the very fact of them weighing something that means they circle the Earth. If they weighed nothing, suggesting true zero-gravity, they'd just shoot off unimpeded into space.
Orbit is a controlled Free-Fall rather than zero-gravity. So it still masses 1500kg, but rather than weighing ~14,715N it weighs nearer 13,250N (ISS sees about 90% of Earth surface gravity). It's just missing the Earth as it falls because it's moving sideways so fast- that's why spaceships need to go quickly sideways rather than straight up. Straight up on a rocket would work, but you'd need to continue thrusting up until you left Earths (and the Suns) gravity well completely or you'd just start to fall.
1st stage worked perfectly and payload got to orbit and deployed all satellites.
Flipped stage end over end. AFAIK never done before. Successful
Re-fired main engines. Normally 1st stage engines ignite at Sea Level pressure and fire once. So AFAIK never done before. Successful
Flipped stage end over end back to original orientation. AFAIK never done before. Successful
But stage started to spin (around it's long axis?). Propellant didn't get to engine (AFAIK this was going to need 1 engine firing) and stage crashed.
Actually earlier posters are wrong. This is rocket science because AFAIK no one has investigated the problems of propellant "slosh" in tanks this big or under this much motion ever before. A lot of the work on fluid flow in spinning tanks seems to have been done by the US Army for artillery shells loaded with binary nerve agents. A 95% filled tank spinning at several 1000s RPM is a very different beast to something which is maybe 5% filled (one of which is partly boiling off), although both are actually in "free fall."
Yes, in principle all this can be modeled for the flight conditions (insofar as they are known) and RP1 and LOX are fairly conventional liquids. No doubt Spacex ran many sims but the fact remains that real life is the only certain test for this.
I also got the impression that Spacex were also worried that their radar altimeter would not get good enough reflections off the sea surface to trigger ignition, but obviously this time round that was academic. Personally I always thought that was easy to test with a helicopter over open water.
Note that Spacex's approach of using (nearly) every launch to find out more and use that to drive improvement is one that any LV mfg could used if they cared about improving their product. But as everyone else seems to depend on the customer buying upgrades they don't bother.
Note that Spacex's approach of using (nearly) every launch to find out more and use that to drive improvement is one that any LV mfg could used if they cared about improving their product. But as everyone else seems to depend on the customer buying upgrades they don't bother.
Trying something new costs money, both for the manufacturer, and for the guys hitching a ride. I don't know what the insurance is like, but I'm guessing an experimental SpaceX launch could attract high premiums.
Come on El Reg!
Yes, it's great that SpaceX got their new bird away without problems but surely you could have
A: Said a bit more about the launch - details, please.
And
B: Said more about the 1st Stage - post-separation. SpaceX wanted to exhibit a degree of control over the 1st stage on the way down - they did - but the 1st stage began to spin, sloshing the fuel away from the pumps, causing the engines to flameout.
Oh, way to go, SpaceX!
It might be just me but I imagine the various presidents & vice-presidents at ULA & Cygnus will be preparing to cash-in their stock options about 5 years from now as it becomes clear that they can't compete on price.
"@John Smith 19, thanks for completing the article the Reg apparently couldn't be bothered to finish."
That's flattering but perhaps a little harsh on El Reg.
24 hour news cycles, editing deadlines etc mean sometimes going with 1/2 a story now rather than the full story later.
Of course this being a website and not a paper document there's always updates and corrections....
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