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23 hours ago, ment18 said:

They scrubbed at 30s.  They waited until then to see if the upper winds would improve enough to fly.

I know they stopped the count at T-30, but they decided that they weren't going to launch at ~T-3 minutes. They just proceeded with the count to obtain additional information, as they commentary guy said.

Anyways, glad that they launched today- but too bad I missed it.

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21 minutes ago, tater said:

He's saying that a Russian engine is brilliant. He's also stated in the past that his favorite rocket that isn't his is Russian.

Any mention of Musk whatsoever causes them to spazz out. It’s irrational hatred, since he stands in anathema to everything they think about how the field of endeavour should operate.

Plus you’re about to start a flame war with such a description of Zenit.

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On 12/18/2018 at 5:48 PM, sh1pman said:

Why didn’t they keep extendable solar arrays, like those on Dragon 1? Cheaper to make fixed ones? More reliable?

Extendable arrays have more failure modes and more challenging abort aerodynamics. 

On 12/18/2018 at 4:17 AM, RealKerbal3x said:

We've got to the point now where SpaceX not landing the booster is the rarer occurrence.

We've been here for a while now.

On 12/18/2018 at 4:19 PM, cubinator said:

Trunk has 4-way symmetry, capsule has 3-way. Looks pretty well lined up to me. See, the hatch goes perfectly over the nearest fin.

Trunk fins are four-symmetric but radiator/solar array placement is bilaterally symmetric. The capsule has eight SuperDracos in four pods, arranged dual-bilaterally (they are at approx 60°, 120°, 240°, and 300°, with fins at 0°, 90°, 180°, and 270°). This allows structural space for the ingress/egress hatch over the 0° fin. 

On 12/20/2018 at 1:36 PM, Ozymandias_the_Goat said:

Yeah, the launch itself is generally unexceptional (I suppose that’s a good thing). It’s only the landings that make it worthwhile.

Blasphemy!

#EveryLaunchIsSpecial
#NotAllLandings
#YesEveryLaunch

Edited by sevenperforce
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On the topic of the current launch:

Woo!

Those who are willing to go frame-by-frame and chart altitude-v-time and speed-v-time will have a field day. We finally get to see now exactly what the Block V upgrades are capable of, given that this is an expendable mission with no sandbagging. Hopefully someone will do exactly that.

Successful liftoff, MECO, sep, SECO-1, SECO-2. In extended coast before deployment. As I understand it the second stage will provide pointing before separation and the GPS-III will raise its own orbit.

6 minutes ago, Ho Lam Kerman said:

Anyways, does anyone have an idea what sort of orbit they're targeting?

This GPS-III will end up at a semi-synch MEO with an apogee at 20,200 km altitude. It looks like perigee for the transfer orbit was around 1200 km, which is surprising. I would have expected a perigee between 200 and 400 km for Oberth advantage. Maybe it's a thrust issue on the payload.

The semi-synch will have a 12-hour orbital period so it will circle the earth twice per day.

This bird is 3.9 tonnes. We would need to see a detailed speed-vs-time chart to see if any performance was reserved on the second stage.

Random: was the tip of the nose cone painted differently or was that only shadow?

And, re earlier: WE HAVE GRASSHOPPER ON STEROIDS!

Although if Grasshopper was F9, what's this? Giant Locust? Mantis? 

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We have spacecraft sep! The bird is free!

Grand closing of a wonderful year for SpaceX indeed!

22 minutes ago, sevenperforce said:

Random: was the tip of the nose cone painted differently or was that only shadow?

One part of me says that if you look at the roofs of the other structures, they are illuminated by the Sun, so the light must be shining from above. If so, the tip of the F9 should not be in shadow.

The other part says that SpaceX wouldn't be so ridiculous to waste payload capacity and potentially cause weird aerodynamic effects by painting the tip of their Block 5 grey.

Someone ask Elon while the Twitter storm lasts! (Too bad I don't have twitter.)

12 minutes ago, sevenperforce said:

Someone is shading Electron....

They had to use electric turbo pumps. Their rocket is literally called the Electron.

Edited by Ho Lam Kerman
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51 minutes ago, Ho Lam Kerman said:

One part of me says that if you look at the roofs of the other structures, they are illuminated by the Sun, so the light must be shining from above. If so, the tip of the F9 should not be in shadow.

I think the top of the new fairings (fairing 2.0) have some TPS now. I'll try and find a good image.

Screen-Shot-2018-12-18-at-9.21.50-AM-879

Edited by tater
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15 minutes ago, MinimumSky5 said:

Maybe it's a better TPS for reusability? Why they'd try it on this launch, though, is beyond me. 

Maybe the fairing is like that, and they masked out where they painted it white, and simplydon't paint that area (vs additional material).

If that part gets scorched on reentry, might as well not paint it.

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I recall the SR-71 being painted black despite being made out of titanium because in the regime it was in, matte black things would stay cooler than shiny metal, since it radiated away more heat and compression and friction were the driving sources of heat.

I wonder if BFS will eventually be painted black. If it keeps those solar panels vacuum thermal control won't be a problem.

Edited by Mad Rocket Scientist
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