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#1 2021-07-29 08:36:16

EdwardHeisler
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Registered: 2017-09-20
Posts: 357

SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

SpaceX Orders Employees to Starbase Immediately & Orbital Launch Tower To Be Ready August 5th!


https://www.youtube.com/watch?v=SgBi0JsUDis

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#2 2021-07-29 18:57:56

louis
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From: UK
Registered: 2008-03-24
Posts: 7,208

Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

Presumably you are horrified by this assault on planetary protectionism?


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#3 2021-07-29 19:01:09

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 29,306

Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

If they launch before approvals there will be problems for the dream....

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#4 2023-04-20 07:45:11

tahanson43206
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Registered: 2018-04-27
Posts: 18,127

Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

That launch tower got a work out today, April 20, 2023!

The Starship full stack cleared the tower and appears to have completed first stage ascent without incident.

An impressive RUD occurred as the moment of stage separation approached. 

It appears to me that the first stage went into flip maneuver while the Starship was still attached.

(th)

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#5 2023-11-15 18:53:51

tahanson43206
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Registered: 2018-04-27
Posts: 18,127

Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

The launch tower may get a chance to show it's stuff...

https://www.msn.com/en-us/news/technolo … 9600d&ei=9

SpaceX Super Heavy-Starship cleared for Friday launch attempt
Story by William Harwood  •


(th)

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#6 2023-11-17 09:52:55

tahanson43206
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Registered: 2018-04-27
Posts: 18,127

Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

The launch tower is now (re)scheduled for a launch try Saturday morning.

Per CNN...

(CNN) — After months of rebuilding and clearing red tape following the April explosion of the Starship system’s first test flight, SpaceX is set for its next attempt.

The megarocket — the most powerful launch vehicle ever built — was expected to lift off on Friday, but SpaceX CEO Elon Musk said in a social media post on Thursday that the company would hold off until Saturday to allow for time to replace a small rocket part.

The company is targeting a 20-minute launch window that opens Saturday at 7 a.m. CT (8 a.m. ET), according to the SpaceX website.

Musk shared that the reason for the delay was the need to replace an actuator — or a mechanical component that allows movement — on one of the rocket’s grid fins. Grid fins are metal, mesh squares that line the top of Starship’s Super Heavy rocket booster, and they’re used to orient the booster as it heads in for a landing after flight.

Riding on Starship’s eventual success is the company’s hopes for human exploration of the moon and Mars.

I hope Louis is in good health and able to tune in for tomorrow's attempt.  As a reminder, this will be the first attempt to use the hot staging technique demonstrated by the Russians in the past, with their expendable rockets. This will be an attempt with a re-usable first stage, except that this ** particular ** first stage will be discarded.

(th)

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#7 2023-11-17 10:30:38

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,848
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Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

Directly from SpaceX:
Starship's Second Test Flight

The second flight test of a fully integrated Starship is set to launch Saturday, November 18. A twenty-minute launch window opens at 7:00 a.m. CT.

A live webcast of the flight test will begin about 35 minutes before liftoff, which you can watch here and on X @SpaceX. As is the case with all developmental testing, the schedule is dynamic and likely to change, so be sure to stay tuned to our X account for updates.

The web page has more information if you want details. Most importantly it has a button to watch the launch live.

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#8 2023-11-18 01:48:51

Steve Stewart
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From: Kansas (USA)
Registered: 2019-09-21
Posts: 161
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Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

Rob,
Thanks for the link. I hope all goes well. I would call it a success if the hot staging works and the 1st stage separates okay. Anything that survives after that is icing on the cake.

Tom,
Does anyone have contact with Louis? He seemed to have stopped posting abruptly. I wondered if something bad had happened. I hope he is in good health too.

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#9 2023-11-18 05:15:24

RobertDyck
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From: Winnipeg, Canada
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Posts: 7,848
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Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

I find it interesting they're using hot staging like the old Soviet N1 rocket. Super Heavy has 33 engines while the N1 first stage had 30 engines. N1 also uses hot staging.

Why change from traditional staging? It works for Falcon 9 and Heavy. My understanding is the interstage clamps didn't release. That can't be fixed?

Whatever. I wish them full success. T minus 1 hour and 45 minutes.

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#10 2023-11-18 07:26:08

tahanson43206
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Registered: 2018-04-27
Posts: 18,127

Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

This post comes in after the launch attempt...

It appears that the second stage had almost reached the end of it's burn, when it self-destructed.

The first stage had completed it's burn, hot staging succeeded, and the stage self-destructed.

I'm looking forward to post-flight analysis and reporting.

It appears that this was a successful test, but there are still a few bugs to work out.

***
For RobertDyck .... your question about why the change to hot staging is good one, and this is an opportunity for NewMars members to find links that explain the change.  I can recommend Dr. Stanley's video about the first test flight and the stage separation technique that was attempted then.  That stage separation technique involved attempting to twist the stages apart.  I'll try to find a link to Dr. Stanley's presentation, which is on YouTube via LinkedIn.

(th)

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#11 2023-11-18 07:36:12

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
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Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

Wow! Whoopee! Woo hoo! It launched. The launch complex is not damaged. All engines on Super Heavy worked. Hot staging worked, stages did separate. Second stage did ignite and enter space.

However, the booster was terminated after separation. Why? They weren't going to attempt a landing simulation in the ocean, just drop the stage. So why trigger the flight termination system? (It blow'd up real good!)

Communication was lost with Starship. After a few minutes SpaceX concluded it was RUD (Rapid Unscheduled Disassembly). It was being tracked, but video cut out. No video of what happened. sad If Elon wants to carry humans, he will have to get this more reliable. Overall a success, but frankly I was expecting to see a belly flop in the ocean. By that I mean a hard splash down. I'm disappointed it didn't make it. Considering delays imposed by regulators, the rapid test/fail/fix/retry won't work.

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#12 2023-11-18 07:42:04

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,848
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Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

When I went to the SpaceX website and pressed the Watch button, all I got was a black display with a tiny white X in the corner to close. I used my Android smartphone with Firefox browser. My girlfriend suggested it might be blocked in Canada due to the ban of news on social media. But this isn't social media. They didn't rebroadcast content from some mainstream media company, it's their own content. So it shouldn't be blocked. I had to watch YouTube live feed from What About It, feed from Felix. Did anyone else have that problem?

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#13 2023-11-18 08:22:33

RobertDyck
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From: Winnipeg, Canada
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Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

Thanks Tom. I looked for the YouTube video you suggested. I found it here Starship's innovative stage separation, using no hardware besides clamps, illustrated

This explains what they were trying to do. It sounds good, but ignores a concern I have. Connection of the two stages will most likely be a stainless steel cylinder of one stage that tightly slides into a stainless steel cylinder of the other. This counts on the stages easily sliding apart when the clamps release. My concern is any tortional force applied to the nested cylinders will cause friction that will jam them together. These are two very large moving objects, they will have dynamic movement. If stage separation occurs in the upper atmosphere, there will be a tiny bit of aerodynamic drag. That will apply more tortional (twisting) force. And cryogenic cooling will cause thermal contraction of the metal. Aerodynamic force through the air at supersonic speed will cause heating. Big rocket flying faster than the speed of sound will cause air compression, which causes heating. Where will the heating occur? Shockwaves move as speed changes. These heat changes will cause thermal expansion/contraction that will jam the cylinders together. Apparently that happened.

Hot staging has another potential problem. Igniting rocket engines just inches from the first stage could damage the first stage. If they want to reuse it, that may not be a good idea. Yes, the hot stage ring has a dome to cover the top of the first stage, but still.

My recommendation: use the same system as Falcon 9. That is pistons with helium to push the stages apart.

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#14 2023-11-18 08:57:31

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
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Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

I found a replay of the SpaceX feed with no additional commentary. The SpaeX YouTube channel only has live feeds, no recorded video.
Starship second launch

Notice all engines of Super Heavy worked, no failures. It cut back to only the centre 3 engines for staging. However, after separation while Super Heavy was tumbling, random engines of the centre cluster and middle ring turned on and off. Possibly due to fuel flow problems as tumbling meant liquid propellant would no longer reliably flow into feed lines.

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#15 2023-11-18 12:03:23

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 29,306

Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

From the last time to the present, it seems that many questions have been quelled from the nay sayer crowd. The feat will need many more launches to prove confidence with putting men on it but that's not an issue as its can do so with on orbit transfer of cargo to ISS or other such location of choice.
Will look forward to more updates and information critical to further use of the vehicle for lunar manned missions and mars in the future.

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#16 2023-11-18 15:24:02

kbd512
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Registered: 2015-01-02
Posts: 7,606

Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

Starship Super Heavy's booster stage made it all the way through MECO without incident, but the engines started failing on the boost-back burn, probably due to cavitation in the turbopump impellers because the propellants were no longer resting against the bottom of the propellant tanks.  The moment an engine sucks in a big gulp of gaseous propellant, it's doomed to failure.  I think the same thing happened to Starship itself.  This is why Saturn V had ullage motors- to seat the remaining propellant over the feed lines before the main engines fired and created forward acceleration to do that naturally.

There were no "rock tornadoes" back at the pad, either, so Stage 0 survived intact.  I think another test flight with a revised maneuver prior to the boost-back burn should be SpaceX's first priority, as well as booster stage recovery.  The upper stage will require the use of ullage motors, which means a minor redesign or perhaps a longer burn if it already has ullage motors.

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#17 2023-11-18 16:23:51

Steve Stewart
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From: Kansas (USA)
Registered: 2019-09-21
Posts: 161
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Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

RobertDyck #12
When I went to the SpaceX website and pressed the Watch button, all I got was a black display with a tiny white X in the corner to close.

...

Did anyone else have that problem?

Rob I didn't have any problem at all. I went to the link you posted (#7) about 3 minutes before launch, clicked on "watch" and it worked fine. After it was over, they announced this was the end of their coverage. I think the screen went blank after that and some music came on.

There are a number of articles about the launch on Space.com.

s5Z05ng.jpg


Here's an article from Gizmodo.com.

SpaceX’s Starship Clears Crucial Hurdle in Dramatic Second Flight Test.

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#18 2023-11-18 16:34:43

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,615
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Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

Well,  I finally found some video to see.  Launch with water deluge looked like it worked fine.  I saw nothing that looked like the flung debris last time,  and all 33 engines were working all the way to staging. 

The shutdown to 3 Superheavy engines for staging looked successful,  as did the ignition and staging of Starship away from Superheavy.  There was something going on with those engines right before Superheavy exploded,  but I could not tell what it was.  Those 3 engines should have provided the ullage thrust necessary to light-off Starship,  and it appeared they did. 

They also should have supplied the thrust to settle the propellants in Superheavy during the flip,  but maybe it wasn't enough,  as the flip seemed to happen rather quickly.  It would be hard to say from the video whether whatever was going on with the engines blew up the stage,  or the termination system blew up the stage.  I heard nothing in the narration to indicate whether SpaceX knows,  either. 

As for Starship,  the consensus seems to be that it blew up right near end-of-burn,  which at only 4 minutes flight time,  would be the burn putting it onto the transfer ellipse taking it to its orbit altitude,  for which there would have to be a small circularization burn.  As long as the engines burned,  there should have been no problems keeping the Starship propellants settled.  The ullage issue would come up for the relight for the circularization burn,  about 40 minutes or so into the flight. 

Here's something to think about:  the forward Superheavy tanks are LOX tanks unless I am mistaken.  LOX doesn't suffer from leaks the way LCH4 does,  with LH2 being the worst of all about leaks.  If the staging damaged the LOX tank, they would have lost the minimal tank pressurization,  which would upset propellant feed to the engines,  dependent upon,  among many other things,  the net positive suction head for the LOX turbopump inlets. 

As for whatever happened to the Starship upper stage,  who knows?  It will be a while yet before they figure this out.

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#19 2023-11-18 17:59:34

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 29,306

Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

Cavitation was the due to not having a helium heated pusher gas to keep it from moving or not enough of it as was seen early in the falcon development.

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#20 2023-11-18 18:02:07

RobertDyck
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From: Winnipeg, Canada
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Posts: 7,848
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Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

Updated July 6
KJugXyH.jpg

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#21 2023-11-19 09:58:11

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,615
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Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

Interesting and informative picture,  Rob.  I seem to be wrong about LOX being in the forward tanks.  The language might indicate a source for this in Germany. 

I do not believe the inert weight figures,  at least for Starship.  Those were running about 120 tons,  per Musk,  during the earlier Starship-only flights.  And that is without the internal fitments for passengers and freight,  or any proper landing legs. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#22 2023-11-19 14:12:25

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
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Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

Yes, drawn by an artist not working for SpaceX, but as accurate as he could make it based on SpaceX announcements. Some graphics show the Starship LCH4 header tank as a sphere at the bottom of the main LCH4 tank, and LOX header in the nose. This graphic shows.them both in the nose. Here's statistics directly from the SpaceX website as of this minute.

Payload Capacity 100-150 t (fully reusable)

Starship upper stage
Height 50 m
Diameter 9 m
Propellant Capacity 1,200 t
Thrust 1,500 tf

Super Heavy first stage
Height 71 m
Diameter 9 m
Propellant Capacity 3,400 t
Thrust 7,590 tf

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#23 2023-11-20 19:42:28

GW Johnson
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From: McGregor, Texas USA
Registered: 2011-12-04
Posts: 5,615
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Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

I got to a several videos from several angles,  including some slow motion stuff.  I could see bright spots appearing here and there on Starship's heat shielded belly.  I interpreted those to be losses of several heat shield tiles. 

I also saw what I thought was abnormally-large plumes of unburnt propellant coming from Superheavy before and during the staging event.  The Superheavy stage seemed to rotate past the right attitude for its boost-back burn,  still spewing large white plumes of what I interpreted as unburnt propellant.  Then I saw several irregularly-occurring flashes of light which I took to be attempted engine ignitions that failed.  I also saw what looked like some sort of engine plume coming out nearly perpendicular to the stage centerline,  which would be abnormal indeed.  Then Superheavy blew up.

Meanwhile,  Starship seemed to be flying quite well on 6 engines,  the bright light from which appeared to show 3 smaller sea level "spots" and 3 larger "vacuum" spots of brightness.  I've seen nothing yet to indicate why contact with it was suddenly lost later.  But I am disappointed there was no telescopic footage being taken of it far downrange where the problem,  whatever it was,  occurred. 

They may want to rethink that and add more coverage farther downrange.  If I was the FAA,  I would insist on that for the next flight.  There's nothing like footage to help figure out what went wrong.  Could be taken from boats underneath the flight path.

I have seen varying accounts of the flight plan,  but it appears Starship entered a near surface-grazing transfer ellipse toward the intended orbit altitude (accounts say 150 miles = 240 km),  but was not going to do a circularization burn.  Instead it would just stay on the near surface-grazing transfer ellipse,  going around almost but not quite once,  to an entry near Hawaii,  about 80 minutes or so after launch.  You could see the pitch angle that starts the gravity turn onto the transfer ellipse,  about a vehicle length off the launch pad.  That's normal. 

Had Starship survived the trip into space,  I rather think it would have failed during entry from all the lost tiles.  There were several missing,  quite visible in some of the footage.  That many burn-throughs is probably a guaranteed breakup in midair coming back.  Entry is a rather unforgiving environment.

Superheavy looked different than I remember from earlier tests and set-ups.  There are four strake-fin-looking things along its sides,  in the bottom half of the stage.  I don't remember seeing anything like that,  on earlier examples stacked on the pads.

GW

Last edited by GW Johnson (2023-11-20 19:53:21)


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#24 2023-11-21 14:48:19

Oldfart1939
Member
Registered: 2016-11-26
Posts: 2,419

Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

Hello again, everyone. I've been away far too long, so this event is where I jump back into the discussions. The biggest "failure" was the Starlink connection with both vehicles which prevented the usual "go-pro" camera footage from being televised. We have yet to see the video from NASA's WB 57 which was supposed to be flying at nearly 60,000 feet to track the launch. Everything so far is speculation and educated guesses, although my initial thoughts mirror those of KBD512 and GW; cavitation in the sloshing fuel tanks/LOX tanks caused turbopump starvation and destruction of the engines. The FTS has been identified as the cause of both stages' destruction--as mandated by the FAA.
I watched the whole launch on Everyday Astronaut, where the tracking by associates of Tim Dodd did a marvelous job. I was seeing the heat shield tiles raining off the Starship, as did many others here on this website. Secure fastening of this shielding seems to be a major area of future concern once the engine restarting issues and unexplained FTS of Starship are resolved. Only AngryAstronaut provided some real sound bites--which were awesome. I normally like the SpaceX coverage the best, but as I'm not yet a member of "X;" that coverage was black screen. I normally follow Felix on What About It, EverydayAstronaut, Marcus House, Scott Manley, and AngryAstronaut for a spectrum of information and commentary. I need to get hooked up to "X" for future missions/launches.

Last edited by Oldfart1939 (2023-11-23 22:08:48)

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#25 2023-11-21 15:08:46

kbd512
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Registered: 2015-01-02
Posts: 7,606

Re: SpaceX Orbital Launch Tower to be Ready August 5th for Testing!

Oldfart1939,

Welcome Bach!

and...

Welcome Beethoven!

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