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3 hours ago, Ultimate Steve said:

Beautiful vehicle, a marvel of engineering and an excellent first step towards rapid reusability and a sci-fi future, that we stuck with for decades and never got followed up with a second step.

The bulk of the troubles people tend to have with it is the gap between what it was billed as being able to do and what it actually did. Most of its turnaround, reusability, and cost goals were never reached. I'm all for aiming high, but you can't get something that ambitious right on the first try. Going from Apollo to 2001: A Space Odyssey in one step was never going to work, but they tried to get close with the one try they were allowed. We ended up with something that was promising but not particularly revolutionary. Instead of iterating on the shuttle (well, they did minor iterations), we kept the same design for 30 years and never committed to properly funding replacements or upgrades until after it was gone.

This was however largely a funding/political problem, though.

I say the main issue with the shuttle was that it was overturned like an F1 race-car, you had no margins and needed serious refurbishing between launches it also let to the loss of two crews and ships. 
But yes they was very capable crafts, building the IIS was the big one.

I assume we will get an shuttle like starship or other heavy lift craft down the line, large cargo bay and a arm, probably multiple and able to operate well outside LEO, GEO, moon orbit and out to Lagrange  points. Manned and spacious compared to the shuttle they are doing longer missions. 

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If Dreamchaser proves to be capable of rapid reuse and then they combine it with a reusable launcher then we will finally get what Shuttle was supposed to be - a rapidly reusable human acces to space. Eventually working in tandem with Starship and New Glenn as heavy cargo launchers we could. finally have what was envisioned in 70s before all the compromises came into Shuttle program to accomodate different interests from those footing the bill. Better late than never I guess

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1 hour ago, Cuky said:

Better late than never I guess

More like STS just came way too early.

As I said in another thread, STS was the definition of something "ahead of its time." Rapid reusability wasn't lost back then because of lack of funding, it was lost because of technological limitations. No amount of funding would have made it work.

Now is the time.

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STS again.  Snore...  A dirty secret inside NASA (ignored by management) that it had a 1-in-100 probability of catastrophic failure.  For thirty years...

We on the moon yet?

You know the saying: "if you can't lead and you can't follow, get out of the way"

 

Edited by Hotel26
@BobSnark
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On 3/27/2024 at 8:09 PM, tater said:

 

 

 How about showing it can get anywhere near the 150 tons payload to LEO claimed? 

 What IFT-3 showed was a launcher with 0 tons to LEO payload capability, even when fully fueled and fully expending its propellant. Then how can it do Artemis Starship HLS refuelings when it gets 0 tons to LEO? 

  Bob Clark

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Okay, okay, you win, I'll call SpaceX and tell them someone wants a proper mass simulator on the next flight. Except they're not accepting my calls for some reason.

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1 hour ago, Exoscientist said:

What IFT-3 showed was a launcher with 0 tons to LEO payload capability, even when fully fueled and fully expending its propellant. Then how can it do Artemis Starship HLS refuelings when it gets 0 tons to LEO? 

sevenperforce already explained how they underfilled the booster earlier this week (so it wasn't fully fueled), and it's possible they also took a different trajectory that burned more fuel without actually putting themselves into orbit (I'm sure we've all done that in KSP intentionally or otherwise). Those two combined would leave virtually no fuel remaining (aside from what they needed for their tests), which is what they want - less of a risk to have a near-empty ship in space in case they lose control, and they need to take those steps because there's no payload being lifted. It's a cautionary measure for a non-operational vehicle, and doesn't imply anything about payload capabilities.

Because it's either that, or SpaceX somehow built a rocket more than twice as powerful as the Saturn V that can't put anything into orbit, and only just figured that out. Do you think that has any plausibility, or is this some sort of contrarian inquiry to spark debates?

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 Common Sense Skeptic, a well-known critic of SpaceX, presents an argument that considering all the mission objectives IFT-3 should not be regarded as a successful test:

 

  From the video :

68103-A49-6-FE9-4-DD0-B629-C898-F957-F46

 

  Bob Clark

Edited by Exoscientist
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People, if somebody's posts are really bothering you, how about you just skip over them? Or set that person to ignore? Then you can go on your way and never be troubled by that person again. 

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1 hour ago, Exoscientist said:

 Common Sense Skeptic, a well-known critic of SpaceX presents an argument that considering all the mission objectives IFT-3 should not be regarded as a successful test:

Appreciated a short synopsis. There's no way I was listening to a whole big post.

With respect to the booster engine landing burn relight: once grid fin control was lost, the booster return was expected to be a failure. If you'll recall, the CRS-16 mission suffered a similar fate when one of its grid fins entered a hydraulic stall and stuck hard-over. There, the single engine tried valiantly to correct for the problem, but it was already off-nominal. This is the same situation. Engine relight depends on a number of factors, including vehicle stability, and so once you are spinning out of control you don't expect engine relight to work.

He has an obvious error at item 4 -- "orbital" velocity. There is no indication whatsoever that Starship failed to reach its intended velocity or trajectory.

He then says that the payload door demo was not successful because the vehicle started to spin once the payload bay vented to space. That doesn't make any sense. It's clear that Starship lost attitude authority (likely due to frozen propulsive vents); whether or not it lost attitude authority doesn't impact the success of the payload door demo. He subsequently says "we have no indication that the test took place" and claims that this is because we did not see any graphical change in the LOX levels, which is also nonsensical; there was no indication that the GUI was supposed to show this. This should be a questionmark, not a failure.

Finally, he claims that because the re-entry time was three minutes different from the estimate from some random person on the internet, this meant it did not re-enter where it was supposed to re-enter. I shouldn't have to explain how silly THAT is.

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2 hours ago, Exoscientist said:

Common Sense Skeptic, a well-known critic of SpaceX

CSS is a discredited hack who hate-mongers for clicks and has been proven wrong pretty much every step of the way. Not really a good “source” to call back.

Oh, and also a media thief. 
 

jus sayin…

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11 hours ago, Cuky said:

If Dreamchaser proves to be capable of rapid reuse and then they combine it with a reusable launcher then we will finally get what Shuttle was supposed to be - a rapidly reusable human acces to space. Eventually working in tandem with Starship and New Glenn as heavy cargo launchers we could. finally have what was envisioned in 70s before all the compromises came into Shuttle program to accomodate different interests from those footing the bill. Better late than never I guess

How about take the Dreamchaser design and scale it up to Shuttle scale.  Now that would be something to behold 

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3 hours ago, darthgently said:

How about take the Dreamchaser design and scale it up to Shuttle scale.  Now that would be something to behold 

1. This is the SpaceX thread ;)

2. No need to make anything Shuttle sized, the cargo bay is a mistake. Dream Chaser is a great size, all it needs to move is crew/supplies.

3. ObSpaceX:

SpaceX is targeting no earlier than Saturday, March 30 for a Falcon 9 launch of 22 Starlink satellites to low-Earth orbit from Space Launch Complex 4 East (SLC-4E) at Vandenberg Space Force Base in California. Liftoff is targeted for 7:30 p.m. PT, with backup opportunities available until 11:30 p.m. PT. If needed, additional opportunities are also available on Sunday, March 31 starting at 7:30 p.m. PT.

 

That's 2 launches tomorrow 1.5 hours apart.

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13 hours ago, Hotel26 said:

STS again.  Snore...  A dirty secret inside NASA (ignored by management) that it had a 1-in-100 probability of catastrophic failure.  For thirty years...

We on the moon yet?

You know the saying: "if you can't lead and you can't follow, get out of the way"

 

I mean I know all us oldheads want to see a mars mission on the TV before we die but we probably should use a reusable NSW transfer stage to LMO. 

Edited by Pthigrivi
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Instead of trying to launch 3 rockets within <4.5 hours, they should do the prudent industry thing and spread these 3 launches over at least one Quarter. This just isn't "how it's done."

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Did you, prospective satellite builder, like the video of Starlink broadcasting live from inside re-entry? Do you want your own link? SpaceX is selling!

https://www.reuters.com/technology/space/spacex-says-plans-sell-satellite-laser-links-commercially-2024-03-19/

Yet another way to make money with their satellite internet.

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