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13 minutes ago, Nightside said:

All this assumes that SpaceX launches are profitable. Mr Musk comes from Silicon Valley, where that isn’t a requirement of doing business.

It assumes that his business model is expansive, that is to say that this years number of flights are greater than last years, the number of customers have increased and the costs have fallen.

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2 hours ago, PB666 said:

It assumes that his business model is expansive, that is to say that this years number of flights are greater than last years, the number of customers have increased and the costs have fallen.

This I assume this is based on the block 5 and reuse. still the price increase from F9 to FH is small, indicating its not so much more expensive to launch FH, most of the cost is in the launch itself. 
 

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3 hours ago, sh1pman said:

HAPPENING

Interestingly, side boosters seem to have titanium grid fins, while the central core has aluminum ones. Shouldn't it be the other way round?

HELLS TO THE YESSSSSSS

(excuses himself while the adrenaline rush passes)

Grid fin setup is exactly as I thought, based on the one little image we got all ready.

It's an odd choice. The Block 5 grid fins have more control surface area and can provide a better L/D ratio for the returning stages, which would presumably give the side boosters a better shot at returning. Aluminum grid fins can be used for high-energy entries, like what the core will have, but they are single-use. Maybe they are less-than-optimistic about the core recovery chances and so they are going to use up the aluminum grid fins that way?

Also, WOW at the insides of those reused Merlins.

Another note -- the two boosters are oriented to the reverse of each other. This suggests the design for the side boosters is singular (e.g., they only mount one way) and are oriented appropriately, as needed. Smart.

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20 minutes ago, sevenperforce said:

HELLS TO THE YESSSSSSS

(excuses himself while the adrenaline rush passes)

Grid fin setup is exactly as I thought, based on the one little image we got all ready.

It's an odd choice. The Block 5 grid fins have more control surface area and can provide a better L/D ratio for the returning stages, which would presumably give the side boosters a better shot at returning. Aluminum grid fins can be used for high-energy entries, like what the core will have, but they are single-use. Maybe they are less-than-optimistic about the core recovery chances and so they are going to use up the aluminum grid fins that way?

Also, WOW at the insides of those reused Merlins.

Another note -- the two boosters are oriented to the reverse of each other. This suggests the design for the side boosters is singular (e.g., they only mount one way) and are oriented appropriately, as needed. Smart.

As someone here suggested earlier, maybe they are indeed just burning (haha) through their supply of aluminum fins in anticipation for block 5.

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19 minutes ago, sh1pman said:

As someone here suggested earlier, maybe they are indeed just burning (haha) through their supply of aluminum fins in anticipation for block 5.

Someone, ahem, me.

Poring over the image of the octaweb mating at the bottom. Looks like clasps at the nearest attachment points, plus two pneumatic pushers on each side. Also looks like those pneumatic pushers will rotate up after the separation.

This is really quite complicated.

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2 minutes ago, sh1pman said:

The side boosters need the increased control authority the Ti gridfins provide because of the nose cone, which screws up some of the aerodynamics. The centre core doesn't need that, so they went with Al gridfins.

Oh. Well, that explains that.

Makes sense. The nose cone has lower drag than the bare interstage, lowering the center of pressure, so they'd want to increase the drag on the fore end of the rocket to help with stability.

This suggests that they'd like to burn through all of the aluminum grid fins, but they can't do so with the side boosters.

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1 minute ago, tater said:

They said they'd roll it out in Dec, I would have been surprised to not see this.

Wasn't delayed to Januari because of Zuma?

 

1 minute ago, sevenperforce said:

TEA-TEB.

That stuff that is used to ignite the engines? Cool!

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Some of the engines look like they've been gone over post test (or flight) firing (the shiny ones).

Just now, NSEP said:

Wasn't delayed to Januari because of Zuma?

The LAUNCH was, they said they'd static fire in December.

 

Just now, NSEP said:

That stuff that is used to ignite the engines? Cool!

triethylaluminum and triethylborane,

All engines have been test fired.

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