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‘The fairing deploys a parafoil and has the ability to manipulate it to control descent rate and direction. You can find videos of tests and some of the near misses where it's under the chute.“

Yes, but those facts are already in evidence. I’m looking for the underlying tech that makes recovery work. Tech, which apparently, isn’t working as well as hoped.

Surely SpaceX is not just hoping that the net and the fairing just happen to end up in the same place at the same time.

The Starship Pathfinder tank at Boca Chica had a short life. It was only assembled (for the 2nd time) yesterday.

Nomadd wrote:

The Starship Pathfinder tank at Boca Chica had a short life. It was only assembled (for the 2nd time) yesterday.

Well THAT doesn't look right.... Do they test it under vacuum or something?

Tugg

Tugger wrote:

Nomadd wrote:

The Starship Pathfinder tank at Boca Chica had a short life. It was only assembled (for the 2nd time) yesterday.

Well THAT doesn't look right.... Do they test it under vacuum or something?

Tugg

That's what I thought, but Elon said welds failed at 7.1 bar. Close to the 8.4 bar (6 bar + 40% margin) they needed. They hope to meet specs with a little better fabrication techniques.

Good test-fire of the Falcon 9 ahead of the in-flight abort test of Crewed Dragon, with a no earlier launch date of January 18th:

https://spaceflightnow.com/2020/01/11/s ... bort-test/

Can't wait for that launch. That should be pretty spectacular.

Tugger wrote:

Well THAT doesn't look right.... Do they test it under vacuum or something?

I wonder if they are encountering the same issues as the early Atlas rockets whose integral stainless steel tanks had to be kept pressurized to retain their shape...

Tugger wrote:

Nomadd wrote:

The Starship Pathfinder tank at Boca Chica had a short life. It was only assembled (for the 2nd time) yesterday.

Well THAT doesn't look right.... Do they test it under vacuum or something?

Tugg

Hydrostatic test; deformation likely happened when water above created a partial vacuum when it failed.

JHwk wrote:

Tugger wrote:

Nomadd wrote:

The Starship Pathfinder tank at Boca Chica had a short life. It was only assembled (for the 2nd time) yesterday.

Well THAT doesn't look right.... Do they test it under vacuum or something?

Tugg

Hydrostatic test; deformation likely happened when water above created a partial vacuum when it failed.

I watched the grainy video of the test and you're absolutely right.
It was filled with water, failed at the welds at 7.1 bars, then as the water flowed out of the welds on the side it created a vacuum at the top.
Not a bad test overall then.

Inflight launch abort test has been scrubbed for today due to recovery area weather. Next attempt same time tomorrow.

Congrats SpaceX!!!!!!!! So exciting to see the whole event live on tv!!! Very exciting, now will have to see a launch on the other coast!!!

Inflight abort test was uneventful. Congrats SpaceX!

That was amazing to watch! Especially the detonation of the booster...

Hi... God... was I a good booster?

No, B1046. You were the best booster.

For those that missed the test...

https://youtu.be/RIViYmnknZQ

It's interesting the Falcon 9 booster exploded.

Just prior to the launch, the SpaceX guy said they had run simulations and it was expected to disintegrate. And that they had ships ready to pick up the debris.

I think they learned quite a lot from this test, not only about the launch escape system, but also the structural integrity of the F9 booster itself.

Congrats SpaceX for a successful test!

Booster didn’t so much explode as catch fire.

Post flight press conference

https://youtu.be/ggxhLa2xJOA

The first stage exploded, pretty much as expected. Unexpectedly, the second stage stayed intact until it hit the water, and blew up then.

JetBuddy wrote:

It's interesting the Falcon 9 booster exploded.

Just prior to the launch, the SpaceX guy said they had run simulations and it was expected to disintegrate. And that they had ships ready to pick up the debris.

I think they learned quite a lot from this test, not only about the launch escape system, but also the structural integrity of the F9 booster itself.

Congrats SpaceX for a successful test!

It more ripped itself apart from aerodynamic stress as expected. The RP1 and LOX then mixed, found an ignition source, and turned into a fireball. That had no real guarantee of happening. Looked amazing though. O_O

I thought the second stage was going to be a dummy with no fuel or engine, yet it the fireball it made on impact seems to indicate there was indeed fuel in it...

Why did they use a functional second stage if they knew it wasn't going to be needed?

Francoflier wrote:

I thought the second stage was going to be a dummy with no fuel or engine, yet it the fireball it made on impact seems to indicate there was indeed fuel in it...

Why did they use a functional second stage if they knew it wasn't going to be needed?

It wasn't fully functional as it had a mass simulator in place of the engine. From my understanding they filled it up with the real stuff as swapping it out for something like water simply wasn't worth the effort of putting different stuff through the piping then cleaning it for the following launch. Sometimes keeping it simple, if a touch wasteful, is the better overall option. Scott Manley touches on it in his video about the launch.

The truck from the inflight abort test was fished out of the water, and is in good shape, per Elon Musk:

https://twitter.com/elonmusk/status/1219340904407977984

Francoflier wrote:

I thought the second stage was going to be a dummy with no fuel or engine, yet it the fireball it made on impact seems to indicate there was indeed fuel in it...

Why did they use a functional second stage if they knew it wasn't going to be needed?

It had a mass simulator in place of an engine, but filling the tanks with liquid ballast wouldn't have worked. You need fuel the same density as the methane and LOX or you'd have partially filled, sloshing tanks and the balance would have been screwed up. You'd also have to completely change the ground equipment to handle a different fluid. Pumps and lines would all be wrong. Solid ballast wasn't practical because you can't add it until the rocket is assembled and erected on the pad. Testing as they flew was by far the easiest and safest choice.

Some great pictures of the launch and separation are available at:
https://www.space.com/spacex-crew-drago ... hotos.html

This one I like best:


Tugg

It looks like 60 more Starlink satellites are on the way to clog up low Earth orbit:

https://www.youtube.com/watch?v=0cNn7fg0GSA

Cool feed of the landing too. Looks like those crush cores will require servicing...
Third flight and landing for booster 1051.

Meanwhile, over in Boca Chica, the Starship team continues to have fun with stainless steel tanks:

https://www.youtube.com/watch?v=2TDaMCMEc8Q

Huh, hm, does anybody know why the Crew Dragon test - the one with the volunteers on board - has been delayed from February to April? I thought the crew abort test went perfectly and didn't raise any new issues...

flyingturtle wrote:

Huh, hm, does anybody know why the Crew Dragon test - the one with the volunteers on board - has been delayed from February to April? I thought the crew abort test went perfectly and didn't raise any new issues...

I believe NASA is seriously considering making the Demo-2 mission an extended stay mission, which would require additional training on the part of the crew.

flyingturtle wrote:

Huh, hm, does anybody know why the Crew Dragon test - the one with the volunteers on board - has been delayed from February to April? I thought the crew abort test went perfectly and didn't raise any new issues...

It's scheduled for May because NASA can't change a lightbulb without 4 months of analysis first.

Well, the next batch of Starlink satellites seems to be safely in orbit, but the booster didn't quite stick the landing and ended up bobbing about near the droneship... Not sure what happened yet.

That was the 4th launch for booster B1056, and obviously its last, even though it will be fished out of the water.
All eyes now on B1048 or B1049 to see which will be the first one to achieve 5 successful launches, and hopefully landings.

Missed it by THAT much.
https://youtu.be/jbIdhreCBoo?t=126

Apparently the spray on the edge of the video is from the booster touching down in the water.

Tugg

Starship SN # 1 tank pressure test failure. I believe this is a fluid leak that created a vacuum, followed by implosion of the tank.

https://youtu.be/sYeVnGL7fgw

How many tanks have they blown up now?

Given the severity of the explosion and how the upper tank went flying sideways at quite the speed, I would say that this wasn't necessarily a 'planned' rapid disassembly... Thankfully the upper tank wasn't filled with methane.
I've got a feeling they're finding pressurizing these huge stainless steel tanks is proving harder than they thought. Then again this is uncharted territory and SpaceX tends to learn by blowing up stuff...

Some good news for Falcon Heavy at least, which will launch a NASA probe in 2022:
https://spacenews.com/falcon-heavy-to-l ... d-mission/

Francoflier wrote:

How many tanks have they blown up now?

Given the severity of the explosion and how the upper tank went flying sideways at quite the speed, I would say that this wasn't necessarily a 'planned' rapid disassembly... Thankfully the upper tank wasn't filled with methane.
I've got a feeling they're finding pressurizing these huge stainless steel tanks is proving harder than they thought. Then again this is uncharted territory and SpaceX tends to learn by blowing up stuff...

Some good news for Falcon Heavy at least, which will launch a NASA probe in 2022:
https://spacenews.com/falcon-heavy-to-l ... d-mission/

Only the second. And yeah, SpaceX has a philosophy that is more build cheaper and see what survives. Then fly it so much you can work out the kinks and prove safety before a person sets foot on it.

Francoflier wrote:

How many tanks have they blown up now?

Five. MK1, SN1, two individual test tanks and a header tank in a nosecone. SN1 is "probably" the only one that wasn't expected to kaboom. All the rest were pressured to near or over the expected failure point. They wanted to install an engine in SN1 and fire it. It's likely they didn't intend to fly it. They'd already decided it was only going to be a single engine model, and as heavy as the full vehicle would have been for this model, it wouldn't have been able to carry enough fuel to go far.
It's also the one that cracked my window.

Nomadd wrote:

Francoflier wrote:

How many tanks have they blown up now?

Five. MK1, SN1, two individual test tanks and a header tank in a nosecone. SN1 is "probably" the only one that wasn't expected to kaboom. All the rest were pressured to near or over the expected failure point. They wanted to install an engine in SN1 and fire it. It's likely they didn't intend to fly it. They'd already decided it was only going to be a single engine model, and as heavy as the full vehicle would have been for this model, it wouldn't have been able to carry enough fuel to go far.
It's also the one that cracked my window.

Thanks.

And sorry about your noisy neighbors...
Did any of the debris land outside of the SpaceX site?

Francoflier wrote:

Nomadd wrote:

Francoflier wrote:

How many tanks have they blown up now?

Five. MK1, SN1, two individual test tanks and a header tank in a nosecone. SN1 is "probably" the only one that wasn't expected to kaboom. All the rest were pressured to near or over the expected failure point. They wanted to install an engine in SN1 and fire it. It's likely they didn't intend to fly it. They'd already decided it was only going to be a single engine model, and as heavy as the full vehicle would have been for this model, it wouldn't have been able to carry enough fuel to go far.
It's also the one that cracked my window.

Thanks.

And sorry about your noisy neighbors...
Did any of the debris land outside of the SpaceX site?

A lot of it. I got some good photos of stuff on the south side of the site that night.

Next SpaceX launch is tonight. Sending the Dragon cargo capsule with some 2 tons of supplies to the ISS.
Lift off is scheduled for 11:50pm EST (0450 Sat. GMT).
https://www.space.com/spacex-dragon-crs ... bcast.html

Tugg

Very nice CRS-20 launch tonight. Last flight of Dragon cargo spacecraft.

Another successful launch, Dragon is on its way to the ISS.

-Sucessful pad landing for the booster, which was on its second mission (booster 1059 ex- CRS-19 12/19).
-50th Falcon booster landing.
-Third flight for Dragon capsule 112, but final as Dragon V1 is being retired. All future CRS launches will use Dragon V2.

We should soon see some impressive shots of the 'Falcon nebula' as it was maneuvering for its boostback burn after MECO and the night sky was clear.

A few snippets I heard from pre-launch commentary on one of the Youtube channels:
Apparently this is the highest winds the booster has experienced on landing, although I assume they were talking about altitude winds as winds on the ground appeared calm.

When mentioning the Demo-2 mission, the commentators (not the official SpaceX channel) said that Bob Behnken and Doug Hurley were apparently going through EVA and CANADARM training, which would tend to confirm that NASA will convert Demo-2 into a long duration mission, even if nothing has been officially confirmed yet.

This would make sense as NASA has already stopped buying seats on Soyuz from April onwards and this would be a way to compensate for the lack of astronauts on the ISS after that date due to the delays in both Crew Dragon and CST-100.

Been a few days but no mention here.

SN2 Tank test a success.

https://www.space.com/spacex-starship-sn2-prototype-pressure-test.html

https://youtu.be/QlDBjHa0NkU

Next up:

"Static fire & short flights with SN3, longer flights with SN4, but spooling up the whole Starship/Raptor production line is really what matters," Musk tweeted Monday, in response to a Twitter follower who asked what the path forward now looks like.

Erebus wrote:

Been a few days but no mention here.

SN2 Tank test a success.

https://www.space.com/spacex-starship-sn2-prototype-pressure-test.html

https://youtu.be/QlDBjHa0NkU

Next up:

"Static fire & short flights with SN3, longer flights with SN4, but spooling up the whole Starship/Raptor production line is really what matters," Musk tweeted Monday, in response to a Twitter follower who asked what the path forward now looks like.

Now that you mention it, it’s been a really long time since we’ve seen a raptor engine. I wonder if the starhopper flight taught some serious lessons that need to be addressed. Also, I wonder if investment in a permanent rocket factory would have sped up the tank fabrication process in the long run. Clearly the quality of welding has suffered, and I’m sure the dimension tolerances are terrible for the steel. I wonder how long it will take them to transform the Port of LA site into useful space and it starts producing flight-grade material.

DarkKnight5 wrote:

Erebus wrote:

Been a few days but no mention here.

SN2 Tank test a success.

https://www.space.com/spacex-starship-sn2-prototype-pressure-test.html

https://youtu.be/QlDBjHa0NkU

Next up:

"Static fire & short flights with SN3, longer flights with SN4, but spooling up the whole Starship/Raptor production line is really what matters," Musk tweeted Monday, in response to a Twitter follower who asked what the path forward now looks like.

Now that you mention it, it’s been a really long time since we’ve seen a raptor engine. I wonder if the starhopper flight taught some serious lessons that need to be addressed. Also, I wonder if investment in a permanent rocket factory would have sped up the tank fabrication process in the long run. Clearly the quality of welding has suffered, and I’m sure the dimension tolerances are terrible for the steel. I wonder how long it will take them to transform the Port of LA site into useful space and it starts producing flight-grade material.

I think SpaceX is pretty happy with the Raptor engine, but they now at the point where they need an actual test platform for additional testing.

There is an Ars Technica article on Elon Musk's production plans with Starship:

https://arstechnica.com/science/2020/03 ... ttle-mars/

They are doing a ton of rapid prototyping and trying new ideas for the production of Starship; they are developing new tooling to make sections of Starship much quicker, more consistently, and with a higher level of production quality, and they aren't sparing any expense at doing so.

It also mentions the Raptor engine and where they are at with it; the relevant section is here:

The hardest part of any rocket is the engine. And SpaceX is almost there with the Raptor engine iterations. “We’ve done this with Raptor,” he said. “Like, we’re on Raptor engine 23 or something, Maybe 24. It’s lighter, cheaper, better in almost every way than Raptor version one, which sucked and blew up, basically. One of about six or seven Raptors that blew up, I’ve lost count.”

The point is, Raptor is now in a good place. The next step involves building a spaceship with the tanks and plumbing to harness the power of six Raptor engines. The first two Starships have blown up during pressurization tests, but with each new iteration of Starship, Musk and his band of engineers are learning.

Pad abort on this mornings Starlink launch. Due to engine thrust issue. No recycle launch date yet

https://youtu.be/JVuS4IS2Kvs

New launch date:
8:16 am EDT, Wednesday, it has a 10 min launch window.

Tugg

Launch and deployment was successful, the landing of the booster was not. No info yet on why the 5 time used booster was not recovered successfully

More info later.

Tugg

Tugger wrote:

Launch and deployment was successful, the landing of the booster was not. No info yet on why the 5 time used booster was not recovered successfully

More info later.

Tugg

An engine shut down prematurely on liftoff. It didn't affect the mission but might have affected the recovery.
It was the first Merlin 1D flight failure in over 800 uses.

I'm starting to think that achieving the targeted reusability levels for Block 5 (10 cycles) is going to be harder than Musk let us believe...

Francoflier wrote:

I'm starting to think that achieving the targeted reusability levels for Block 5 (10 cycles) is going to be harder than Musk let us believe...

Hmmm... I don't see that with this particular failure. Musk has always said there would be many failures on the path to success (which really is a truism more than anything). This failure should lead to iterative improvements to other launch vehicles and the cycle continues from there. How many failed landings did we see before the first successful one?

Tugg

Tugger wrote:

Francoflier wrote:

I'm starting to think that achieving the targeted reusability levels for Block 5 (10 cycles) is going to be harder than Musk let us believe...

Hmmm... I don't see that with this particular failure. Musk has always said there would be many failures on the path to success (which really is a truism more than anything). This failure should lead to iterative improvements to other launch vehicles and the cycle continues from there. How many failed landings did we see before the first successful one?

Tugg

In my experience, doing someting never done before (e.g. landing and re-flying fist stages) is hard, but scaling up (i.e. producing a significant number of examples, each example good for a significant number of cycles) is at least twice as hard, and scaling sustainably is at least ten times as hard.

So getting to the 10 cycles milestones may indeed take longer than planned. Still a worthy goal, though.