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Skylon

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Far and away has to be the hottest re-entry so far. The plasma and sparking right before the downlink cut out was spectacular.

I'm guessing BulgariaSat must have had a flatter trajectory? Probably more total heating, but not as high a peak heat nor as rapid a deceleration.

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The sparks were kind of unusual, weren't they?

As for the grid fin glow, you have to take into account that cameras are not nearly as good as human eye when it comes to dynamic range (the ability to properly render both dark and light areas in a frame), so glowing grid fins and a pitch black background are hard to film properly (and realistically), especially when you use cameras with small sensors and then butcher and mangle the data to fit the bandwidth for live transmission.

What I'm trying to say, the grid fins may not have been a whole lot hotter than the ones we saw glowing in broad daylight.

What surprises me, though, is that they still are using aluminium ones. Didn't they say they were going to replace them all for titanium? Am I remembering something that did not happen?

Edited by Shpaget
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1 hour ago, Shpaget said:

The sparks were kind of unusual, weren't they?

As for the grid fin glow, you have to take into account that cameras are not nearly as good as human eye when it comes to dynamic range (the ability to properly render both dark and light areas in a frame), so glowing grid fins and a pitch black background are hard to film properly (and realistically), especially when you use cameras with small sensors and then butcher and mangle the data to fit the bandwidth for live transmission.

What I'm trying to say, the grid fins may not have been a whole lot hotter than the ones we saw glowing in broad daylight.

What surprises me, though, is that they still are using aluminium ones. Didn't they say they were going to replace them all for titanium? Am I remembering something that did not happen?

Maybe the new ones have titanium fins. This booster was probably using its original fins, and will have them replaced with titanium ones, because now they're toast.

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2 hours ago, sh1pman said:

Maybe the new ones have titanium fins. This booster was probably using its original fins, and will have them replaced with titanium ones, because now they're toast.

The original aluminum grid fins are a one use system.  Melts after every flight

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Shotwell talk last night apparently had some interesting information.

Saying December for FH on 39A, with SLC-40 ready. 39A also for crew.

Boca Chica perfect for BFR.

Said the last info on commercial crew (April/Aug) was right. First crew flight has 2 astronauts.

some q&a (from reddit thread as posted by sticklefront):
 

Quote

 

"Does SpaceX have the resources to do the satellite constellation and the BFR together, or will they need to prioritize?"

Answer: "We can do it, no question. We can fund both developments, depending on the time frame you're talking about. But Elon is impatient to get to Mars, so we'll have to get a bit creative with the financing."
 

"How far can SpaceX take reuse?"

"The second stage is not designed for reuse on the Falcon 9 or the Falcon Heavy. However, we do want to bring it back slowly. Currently, it reenters but too hot. On missions with extra propellant, we want to bring it back to see how it behaves, not to recover or reuse. This data will be very valuable. Fairings have been recovered. We expect recovery will be good enough to start regularly reusing them in the first six months of next year."

 

"Will SpaceX work with other companies regarding infrastructure on the surface of Mars?"

"SpaceX is focused on the transportation part of the Mars problem, but people need somewhere to go once they arrive. I don't think it's an accident that Elon started the Boring Company, tunnels will be very important in the first steps of living on Mars, before we build domes and terraform. We want other companies to start thinking about it and working on it, but we'll do it if we have to. I think the BFR might be ready before these other components of actually living on Mars."

 

Moon base vs Mars?

"The moon is to some extent a practice to go to Mars, but given how government programs are, it'll take decades to even get to the moon. If the goal is Mars, then let's not waste resources going to the moon. But a real lunar base would be interesting, that's worth fighting for. Our ship will go to the moon, I'm sure we'll be part of the program that does go to the moon, but it will be designed for Mars."

 

"What is the biggest obstacle to the BFR's success?"

"The composite tanks will be challenge, but we are doing it already. We are currently building a larger raptor right now, and currently have a scaled version of raptor on the test stands. Harder than the rocket, though, will be where poeple are going to live, what will life be like, what will they do there? Also, while the choice of fuel for the BFR was constrained by resource availability on Mars, it is no accident that the final choice of methane is the cheapest energy source here on earth. This will greatly facilitate the economics side of things."

 

How many BFR failures does SpaceX expect in development, and how many can it withstand?

"I'm sure we'll have failures in the development program. However, as far as the launching piece, I'm going to say none (knocks on wood). Also, [referencing Mark Twain anecdote] we've learned so much from previous development programs, and have already hit all the sandbars, so I'm confident in our ability to design it properly."

 

Where will the BFR be built?

"We're looking at building a facility by the water in LA. We thought we'd build it in our factory in Hawthorne, but we priced transport to the harbor, and it came out to $2.5m per trip. It would require taking down stoplights, and just wouldn't be worth it. So we will build a new facility by the water. We will eventually also have a number of production sites by out launch sites."

 

 

 

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29 minutes ago, tater said:

Shotwell talk last night apparently had some interesting information.

Saying December for FH on 39A, with SLC-40 ready. 39A also for crew.

Boca Chica perfect for BFR.

Said the last info on commercial crew (April/Aug) was right. First crew flight has 2 astronauts.

some q&a (from reddit thread as posted by sticklefront):
 

 

 

Both BFR and a constellation? Yea, that sounds realistic :confused: Has SpaceX found a way to reuse money or something?

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1 hour ago, Rocketthrust said:

The original aluminum grid fins are a one use system.  Melts after every flight

Original grid fins are fine for reuse after LEO entries but get torched on GTO entries.

5 hours ago, Shpaget said:

What I'm trying to say, the grid fins may not have been a whole lot hotter than the ones we saw glowing in broad daylight.

What surprises me, though, is that they still are using aluminium ones. Didn't they say they were going to replace them all for titanium? Am I remembering something that did not happen?

The biggest surprise for me was seeing plasma streams coming off the base of the rocket.

I'm guessing they are burning through their supply of aluminum grid fins in anticipation of Block 5.

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1 hour ago, tater said:

"How far can SpaceX take reuse?"

"The second stage is not designed for reuse on the Falcon 9 or the Falcon Heavy. However, we do want to bring it back slowly. Currently, it reenters but too hot. On missions with extra propellant, we want to bring it back to see how it behaves, not to recover or reuse. This data will be very valuable. Fairings have been recovered. We expect recovery will be good enough to start regularly reusing them in the first six months of next year."

This matches what I was expecting. They'd take some steps to try and get it back but reuse is not the goal. Economics of reuse on the second stage just doesn't close, not with the current design.

1 hour ago, tater said:

"What is the biggest obstacle to the BFR's success?"

"The composite tanks will be challenge, but we are doing it already. We are currently building a larger raptor right now, and currently have a scaled version of raptor on the test stands. Harder than the rocket, though, will be where poeple are going to live, what will life be like, what will they do there? Also, while the choice of fuel for the BFR was constrained by resource availability on Mars, it is no accident that the final choice of methane is the cheapest energy source here on earth. This will greatly facilitate the economics side of things."

Good to hear updates on the small vs large Raptor. I wasn't sure whether they'd built the larger one yet. 

I wonder what happens if they end up getting combustion instabilities in the larger Raptor and end up making the scaled version the flight one. Might see BFR scaled even further down.

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5 hours ago, tater said:

Saying December for FH on 39A, with SLC-40 ready. 39A also for crew.

I saw that SFN and Reddit had an updated FH launch to "late 2017" so I was trying to find an update of when SpaceX said this. I didn't see anything in this thread unless it got buried in the Mars colonization discussion.

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9 minutes ago, Racescort666 said:

I saw that SFN and Reddit had an updated FH launch to "late 2017" so I was trying to find an update of when SpaceX said this. I didn't see anything in this thread unless it got buried in the Mars colonization discussion.

It was probably a subtle sequence of winks and nods, since we all knew it was coming. Like about 2:45 into this. :wink:

I predict we’ll see a static fire before the end of the year, but flight will be January. 

Maybe we should start a pool on this...:sticktongue:

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