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Old 15th April 2019, 10:22 AM   #41
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Originally Posted by cjameshuff View Post
Sounds like you didn't read to the point where it said: "The idea is to fly the plane to 10 km (6.2 miles) high before releasing satellites into orbit."

Or even to "the aircraft is designed to act as a flying launch pad for satellites".

Actually, the article's only direct reference to rockets being involved in air launch is in reference to Virgin Orbit.
Oh crappe! I did miss that!
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Old 15th April 2019, 02:49 PM   #42
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r/space are reporting that they have lost the centre core. Heavy seas tipped it over. looks like the Octograbber robot can't handle FH centre cores. Damn.

Good job they made another. I bet they will recover it when they can to do a structural analysis.
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Old 15th April 2019, 04:14 PM   #43
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Originally Posted by Mikemcc View Post
r/space are reporting that they have lost the centre core. Heavy seas tipped it over. looks like the Octograbber robot can't handle FH centre cores. Damn.

Good job they made another. I bet they will recover it when they can to do a structural analysis.
Yeah, that's unfortunate. At least they were already planning on a new core for the next launch, due to not being sure this one would successfully land.

I wonder if there's any wreckage to go over or if it all went over board. Might still be able to inspect the base shielding and see how it performed on such a high energy reentry.
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Old 15th April 2019, 07:10 PM   #44
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Wait, so the centre core landed, but then fell off the ship?
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Old 15th April 2019, 07:28 PM   #45
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Originally Posted by arthwollipot View Post
Wait, so the centre core landed, but then fell off the ship?
Rough seas on the way back, and it wasn't tied down. The robot that they built to grab the landed rockets hasn't been upgraded for falcon heavy yet, and I imagine they didn't want to put people onboard to do the job if seas were rough.
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Old 15th April 2019, 07:34 PM   #46
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Originally Posted by phunk View Post
Rough seas on the way back, and it wasn't tied down. The robot that they built to grab the landed rockets hasn't been upgraded for falcon heavy yet, and I imagine they didn't want to put people onboard to do the job if seas were rough.
Perhaps a refit of Of Course I Still Love You with some tiedowns is in order.
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Old 15th April 2019, 07:40 PM   #47
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An obvious cover-up for the truth: the center was stolen by pirates.
Space pirates.
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Old 15th April 2019, 08:57 PM   #48
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Originally Posted by arthwollipot View Post
Perhaps a refit of Of Course I Still Love You with some tiedowns is in order.
They have a robot that crawls under a landed booster and anchors it by hard points underneath, but the Heavy center core doesn't have the same hard points due to the structural changes/side core attachments. They just need to modify the robot to be compatible.
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Old 15th April 2019, 09:40 PM   #49
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Originally Posted by cjameshuff View Post
They have a robot that crawls under a landed booster and anchors it by hard points underneath, but the Heavy center core doesn't have the same hard points due to the structural changes/side core attachments. They just need to modify the robot to be compatible.
Ah, that makes sense.
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Old 16th April 2019, 01:29 PM   #50
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Originally Posted by cjameshuff View Post
They have a robot that crawls under a landed booster and anchors it by hard points underneath, but the Heavy center core doesn't have the same hard points due to the structural changes/side core attachments. They just need to modify the robot to be compatible.
I don't remember where, but I saw a post saying that the upgrade is supposed to be done before STP-2, which is scheduled for June.
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Old 16th April 2019, 07:45 PM   #51
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I'm seeing some confusion now as to whether the booster fell into the sea or is lying on the deck.
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Old 16th April 2019, 09:04 PM   #52
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Apparently, they thought it went over the side, but its lying on the deck intact but damaged. They think they will be able to salvage the engines and the grid fins.
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Old 17th April 2019, 08:11 AM   #53
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Originally Posted by smartcooky View Post
Apparently, they thought it went over the side, but its lying on the deck intact but damaged. They think they will be able to salvage the engines and the grid fins.
Saw a tweet from Elon saying the engines looked ok so I'm assuming it's on its side with the business end propped up on two legs still.
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Old 17th April 2019, 08:28 AM   #54
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Originally Posted by phunk View Post
Saw a tweet from Elon saying the engines looked ok so I'm assuming it's on its side with the business end propped up on two legs still.
Oh, hadn't thought about the legs! I was somehow picturing it rolling around. The legs would make it nice and stable. I'd think at least one grid fin would be damaged.
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Old 17th April 2019, 11:59 AM   #55
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Originally Posted by Trebuchet View Post
Oh, hadn't thought about the legs! I was somehow picturing it rolling around. The legs would make it nice and stable. I'd think at least one grid fin would be damaged.
The grid fins are in line with the legs so if it tipped over on two legs it probably damaged 2 of the grid fins, if they landed on the deck. Given the dimensions of the ship, there's a pretty good chance though the top of the rocket landed past the edge of the ship. I don't know if that means it's hanging over the edge, or just sheered off.
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Old 17th April 2019, 05:43 PM   #56
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Everyday Astronaut will probably have something on it soon.
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Old 17th April 2019, 06:31 PM   #57
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Originally Posted by arthwollipot View Post
Everyday Astronaut will probably have something on it soon.
I've been watching him, but prefer Scott Manley. Something about that soothing Scottish accent!
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Old 17th April 2019, 06:55 PM   #58
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Originally Posted by Trebuchet View Post
I've been watching him, but prefer Scott Manley. Something about that soothing Scottish accent!
They're both good. I like EA's music.
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Old 18th April 2019, 08:18 AM   #59
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https://twitter.com/spacecoast_stve/...66512079298560

Top half is just gone. Looks like it broke through the fuel tank, maybe the lox tank is intact and floating around out there somewhere? Probably not.
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Old 18th April 2019, 12:46 PM   #60
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Originally Posted by phunk View Post
https://twitter.com/spacecoast_stve/...66512079298560

Top half is just gone. Looks like it broke through the fuel tank, maybe the lox tank is intact and floating around out there somewhere? Probably not.
Pretty sure he's wrong about the "snapped hold-down chains" he mentions in another tweet. They weren't able to board the ASDS to tie it down due to the weather. The angle iron bits and support brace look like they were added in a hurry to hold the remains in place after it tipped, not to hold the landed booster down. The chains just aren't tight.
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Old 22nd April 2019, 09:31 AM   #61
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Apparently there was an "anomaly" during the testing of crew dragon the other day.

https://www.forbes.com/sites/jonatha.../#3c831b83b209
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SpaceX’s historic Crew Dragon spacecraft that launched for the first time last month appears to have exploded, according to reports, potentially delaying the return to flight of humans from American soil.

On Saturday, April 20, an explosion was reported at a test stand at SpaceX’s Landing Zone 1 in Cape Canaveral, Florida. Images and video showed smoke rising from the area following a “reddish-orange plume” in the sky, reported Spaceflight Now.

In a statement, SpaceX confirmed that something had gone awry. “Earlier today, SpaceX conducted a series of engine tests on a Crew Dragon test vehicle on our test stand at Landing Zone 1 in Cape Canaveral, Florida,” they said. “The initial tests completed successfully but the final test resulted in an anomaly on the test stand.”
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Old Yesterday, 12:55 PM   #62
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I don't think it had anything to do with the SuperDraco engines. The explosion happened 8 seconds before ignition.

If I was a betting man and had to pick something, I would pick another COPV failure (like Amos 6).
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Old Yesterday, 04:25 PM   #63
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Originally Posted by smartcooky View Post
I don't think it had anything to do with the SuperDraco engines. The explosion happened 8 seconds before ignition.

If I was a betting man and had to pick something, I would pick another COPV failure (like Amos 6).
This situation is different in some significant ways...the Amos-6 accident was due to a previously unknown failure mode with oxygen freezing between the liner and overwrap of helium COPVs being pressurized while immersed in subcooled liquid oxygen. The Dragon has propellant COPVs that are pressurized from helium COPVs, all of which are close to ambient temperature.

There's less room for surprises with the COPVs this time. They could have been damaged by splashing down in the ocean or by work on the Dragon after it was recovered, but another strong possibility is a problem with the more complicated and finicky part of the system, the plumbing. If a helium valve stuck open or a regulator failed, the helium COPVs could easily overpressurize the propellant COPVs to the point where even a perfectly healthy COPV would burst.
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Old Yesterday, 05:00 PM   #64
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Originally Posted by cjameshuff View Post
This situation is different in some significant ways...the Amos-6 accident was due to a previously unknown failure mode with oxygen freezing between the liner and overwrap of helium COPVs being pressurized while immersed in subcooled liquid oxygen. The Dragon has propellant COPVs that are pressurized from helium COPVs, all of which are close to ambient temperature.

There's less room for surprises with the COPVs this time. They could have been damaged by splashing down in the ocean or by work on the Dragon after it was recovered, but another strong possibility is a problem with the more complicated and finicky part of the system, the plumbing. If a helium valve stuck open or a regulator failed, the helium COPVs could easily overpressurize the propellant COPVs to the point where even a perfectly healthy COPV would burst.
Which makes me wonder why they are persisting with hyperbolic liquid fueled rocket motors and all their attendant complexity, for a launch abort system. Boeing uses hypergolics for their Starliner launch abort system as well, and they too have been having problems with it. Solid rocket motors have been used in the past for this task, and have proven reliable.
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Old Yesterday, 05:05 PM   #65
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SpaceX, at least, also wanted to use the same motors for a soft landing on land.
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Old Yesterday, 05:07 PM   #66
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Originally Posted by Trebuchet View Post
SpaceX, at least, also wanted to use the same motors for a soft landing on land.
Yep, but they have abandoned the propulsive landing idea for Crew Dragon.
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Old Yesterday, 05:37 PM   #67
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Originally Posted by smartcooky View Post
Yep, but they have abandoned the propulsive landing idea for Crew Dragon.
Only when NASA got stubborn about letting them test it on cargo flights. That was far too late to change things.

Plus, solids are heavier, SpaceX has no experience with them, and they involve a whole lot of handling safety and cost considerations of their own. And failure tolerance basically requires the tower approach (the Dragon would spin if a solid in place of one of the SuperDracos didn't fire), and that adds a failure mode where the tower fails to separate. And the fact that the tower would need to separate means there's parts of the flight where the capsule doesn't have an escape system, making it harder to achieve the LOC requirements.
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