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11 hours ago, mikegarrison said:

I take issue with this characterization. The upper stage would get absolutely 0 kg of payload into orbit by itself. The only reason it can get any useful work done at all is because of all the energy that the first stage has invested into it.

First stage is for attitude, second is for velocity.  Because you are high up and already moving downrange you don't need much TWR who makes second stage lighter. 

You even have the tricks of dropping second stage with an higher than intended Ap and use the ballistic trajectory as time to accelerate it into orbit. Atlas uses this but starliner needs two engines on second stage as this toss is not safe if second stage fails as you reenter the atmosphere to steep. 

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In the interests of journalistic integrity, someone please get Chris Bergin to interview a civil engineer. SpaceX's stormwater management/erosion control is embarrassingly bad. Not just from a regulatory standpoint ($$$), but they're undermining their own pad...again.

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14 minutes ago, FleshJeb said:

In the interests of journalistic integrity, someone please get Chris Bergin to interview a civil engineer. SpaceX's stormwater management/erosion control is embarrassingly bad. Not just from a regulatory standpoint ($$$), but they're undermining their own pad...again.

The launch pad, or a different concrete pad?  Those new double digits of pilings (20 or so?) concrete pilings at the launch pad go down like 10+ meters (guesstimate) and they've sunk large corrugated steel sheets (6'-8' deep?) around the pad to alleviate surface erosion.  They also dewatered the ground fairly deep around the pad as they built it back up to get more solids in place near the pad.

Bottom line is that they are on a barrier island / marsh.  I think noticeable erosion is like wind or rain there.  They will likely need to move dirt now and then to compensate in those conditions as periodic maintenance

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37 minutes ago, FleshJeb said:

In the interests of journalistic integrity, someone please get Chris Bergin to interview a civil engineer. SpaceX's stormwater management/erosion control is embarrassingly bad. Not just from a regulatory standpoint ($$$), but they're undermining their own pad...again.

Where? And its very  limited that they can do outside their premises. Area outside the pads is owned by NASA or the Air force in Florida and its an nature preserve at Boca Chica,
And they are not building skyscrapers, 

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2 hours ago, darthgently said:

The launch pad, or a different concrete pad? 

vQKC3wn.jpg

Nothing a few truckloads of rip-rap and a silt settling basin won't fix. I'll be happy to design it if they pay me. (I'm joking--After doing work for Tesla, never again.)

2 hours ago, darthgently said:

and they've sunk large corrugated steel sheets (6'-8' deep?) around the pad to alleviate surface erosion

This is good. Although as someone who has seen 70ft sheet piles sunk on multiple sites, I'd argue that they're not that large. :) I'm just hoping that pad edge doesn't end up cantilevered over a hole.

2 hours ago, darthgently said:

Bottom line is that they are on a barrier island / marsh.  I think noticeable erosion is like wind or rain there.  They will likely need to move dirt now and then to compensate in those conditions as periodic maintenance

"An ounce of prevention is worth a pound of cure." One of SpaceX's stated goals is to have a rapid launch cycle with minimum operations and maintenance effort. Applying some industry-standard best practices would really help them here. At least install the silt fence right, guys. In my occasional stints as a construction and stormwater inspector, I may or may not have bribed crews with cases of beer to improve the quality of their erosion control installs.

2 hours ago, magnemoe said:

Where? And its very  limited that they can do outside their premises.

See above. Just because the site is challenging does not absolve them of the requirement to responsibly manage their stormwater. There's 200+ years of water-rights law in the Western United States that has firmly set the precedents. The core premise of which is, "You don't get to screw up other people's property." It's a foundational tenet of capitalism and private property rights.

2 hours ago, magnemoe said:

And they are not building skyscrapers

They kinda are.

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24 minutes ago, sevenperforce said:

The same way SpaceX deals with all the water after a launch of Falcon 9 or Falcon Heavy.

At pad 39 A they have some large dams close to the pad but outside the fence, back then I was on KSC bus tour we saw an alligator in it. I assume this is for runoff water from the delude system. 
Not seen dams like this at starbase, its just an hole in the ground going down to the ground water level. 
One issue with 39 A is that you might get RP 1 leaks who has to be handled. 

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