SpaceX launches

In reply to Tom_Spangler (Forum Supporter) :

But not multi-stage rockets this big, or with this many engines, or with this type of engine, or even this type of fuel. The Raptor engine alone is a pretty impressive step forward.

So when do we get an orbital launch pad/construction facility? This would all be a hell of a lot easier if that pesky atmosphere wasn't in the way. 

This launch sounded like something from Kerbal, I should probably go watch the video. 

Tom_Spangler (Forum Supporter) said:

Rocket go boom. The SpaceX feed on Youtube is spinning this as a positive test because it made it as far as it did. Is that spin, or is it legit?

We have done product development before. Failures generally mean lots more meetings and analysis. Especially when factoring in the cost of a launch of this magnitude. 
 

These aren't Estes toy rockets. 

this did not age well

In reply to alfadriver :

They're as close to Estes rockets as you get with this class of rocket. Orders of magnitude less expensive to build and launch than anything else this size.

Pre-launch, SpaceX was publicly stating there was only about a 50:50 chance they were going to get all the way through. But the only way to get data on how the whole thing works is to fly it. You can run engines to destruction on test stands, you can do static fires, you can aim blowtorches at heatshields - but at some point you've got to light the candle. And if your candle is less expensive than spending 3 more years running other tests, that's what you do. 

Lots of people in my industry like to just play with spreadsheets and declare they have found the perfect setup, but there's no substitute for getting out on the track and putting in laps with a good test driver.

Keith Tanner said:

In reply to alfadriver :

They're as close to Estes rockets as you get with this class of rocket. Orders of magnitude less expensive to build and launch than anything else this size.

Pre-launch, SpaceX was publicly stating there was only about a 50:50 chance they were going to get all the way through. But the only way to get data on how the whole thing works is to fly it. You can run engines to destruction on test stands, you can do static fires, you can aim blowtorches at heatshields - but at some point you've got to light the candle. And if your candle is less expensive than spending 3 more years running other tests, that's what you do. 

Lots of people in my industry like to just play with spreadsheets and declare they have found the perfect setup, but there's no substitute for getting out on the track and putting in laps with a good test driver.

Very true. I work for a company that makes design and simulation software, so I probably put more faith into virtual testing than most folks do. This is a good reminder that, while the digital twin can get you a long way down the road, at some point you have to actually build the thing and physically test it.

also, RUD, "rapid unscheduled disassembly" is a great term. 

 

Who will be printing the T shirt :)

In reply to Keith Tanner :

There is a big difference in getting a set up wrong on a car compared to putting a space craft into orbit. 
 

Seeing the vitriol against the other space companies, especially Boeing, letting this off that lightly is, well....

And if this is the result of being low cost, this isn't the time to apply all of the cheapness. 
 

One more thing, this seemed to be a stage separation issue, which they have done how many times now?  If it were the control of all of those engines at once, that would make more sense. But to fail when they haven't failed in how many prior launches should be more concerning. 

That's been a term used by SpaceX for years, there are probably already t-shirts.

Here's a remarkably clear video of things going wrong. I apologize for the tweet link, but the live stream is still running so I can't link to a specific moment on YT. I don't think.

https://twitter.com/nextspaceflight/status/1649052544755470338

In reply to alfadriver :

Not really, it's just the industry in question. You've gotta get on track to finish the testing. I have a pile of suspension test items that we designed, built and tested and which failed to pass the tests. In terms of the ultimate value of those parts to our company, they're probably about the same as losing a couple of test rockets.

The problem with Boeing is that they don't test before the race. Well, that plus the fact that they milk cost-plus contracts as much as possible. And when Boeing screwed up the first Starliner launch, it was specifically because they hadn't done the physical end to end test that would have revealed the first problem, they basically assumed it would all work as it did in the simulations. Then they found out about another one that they were able to patch in time. And they're doing these tests with painstakingly hand-built and enormously expensive items, not mass-produced vessels that are being built faster than they can be launched.

The Starship on top of this thing was obsolete in a number of ways. It was really just there to test the heatshields at orbital entry speeds, which you can only do by performing an orbital entry. The only way to test control of 33 engines is to fly 33 engines. It's a shame we didn't get the heatshield test, but we got nearly four minutes of flight data of one of the most complex and the most powerful rocket ever built.

We're used to SpaceX being so reliable that launches are basically forgotten by the public. But this is how they got here. 

Keith Tanner said:

That's been a term used by SpaceX for years, there are probably already t-shirts.

Hell, I heard the term "Rapid Unplanned Disassembly" 20+ years ago. Engineers love little tongue-in-cheek terms like that. For instance, it wasn't a fire, it was an "Uncontrolled Thermal Event". It didn't crash, it experienced "Deconstructive Deceleration", etc. 

In reply to Tom_Spangler (Forum Supporter) :

My favorite is "lithobraking".

alfadriver said:

In reply to Keith Tanner :

There is a big difference in getting a set up wrong on a car compared to putting a space craft into orbit.

Seeing the vitriol against the other space companies, especially Boeing, letting this off that lightly is, well....

And if this is the result of being low cost, this isn't the time to apply all of the cheapness.

One more thing, this seemed to be a stage separation issue, which they have done how many times now?  If it were the control of all of those engines at once, that would make more sense. But to fail when they haven't failed in how many prior launches should be more concerning. 

During the launch they happened to mention that this thing is about twice the thrust of the Saturn V.  The Starship itself is huge; much bigger than anything else ever used as a payload in this kind of configuration.  By SpaceX or anyone else.

So yes, they have made stage separation many many times... but on other, smaller, less-complex rockets.  This was literally the first flight test of the full stack with the super-heavy booster, second stage, and Starship payload.

An oldie but a goodie. This was put together by SpaceX themselves.

Tom_Spangler (Forum Supporter) said:

Keith Tanner said:

That's been a term used by SpaceX for years, there are probably already t-shirts.

Hell, I heard the term "Rapid Unplanned Disassembly" 20+ years ago. Engineers love little tongue-in-cheek terms like that. For instance, it wasn't a fire, it was an "Uncontrolled Thermal Event". It didn't crash, it experienced "Deconstructive Deceleration", etc. 

When I was in architecture school, the engineer that did their best to teach us about the rest of the stuff that goes into buildings used the term "spontaneous dynamic end-of-life" to describe the tendency of big metal halide lamps to explode randomly.

In reply to Keith Tanner :

So Boeing is a failure because it didn't quite make it, but spacex is a success when it has to be destroyed. 
 

Makes sense. 
 

I see a lot of mocking of the flight to the moon and back, and it succeeded. 
Let's at least have some consistency. 

In reply to Duke :

Sorry, they knew all of those details months and months ago. So it is a failure of a system that should be very well understood and scalable. 
 

Again, if this was anyone other than spacex, it would be a disaster. But it's spun as a win. I don't get it. 

In reply to alfadriver :

Depends on the goal. There's a difference between a test flight and a demonstration flight. This was a test flight that was doing a whole lot of things for the very first time. The Boeing miss of the ISS was intended to be a certification of a system and it was purely a pass/fail flight. The Artemis flight was also supposed to be a demonstration, and the sheer amount of pork involved in that project is what makes it laughable.

The booster and ship were obsolete anyhow, so it was either launch them or scrap them. You get a lot more information from launching. It's a very different type of development from what Boeing does, that doesn't make it invalid. This was a successful test in that it generated a lot of data. It wasn't a complete test, but that doesn't make it a failure unless the only goal was to pancake a Starship into the ocean near Hawaii. 

Heck, I did one of our videos on this sort of subject a few years ago. An experiment wasn't working, but I still learned things from it.
https://www.youtube.com/watch?v=BDdEURE0Sjo

(posting here to protect my wife from this)

One thing that was obsolete about the parts of this launch was that they use hydraulics to gimbal engines. They're going to direct electric drive now. And some of the video may show one of the hydraulic power units coming apart, so the loss of control may have been due to this.

I did not realize before today they were going to use a flip to separate the stages. That's nuts.

bobzilla said:

In reply to Tom_Spangler (Forum Supporter) :

It's how spacex seems to do things. It seems to be working for them, but I would be a bit hesitant as a potential rider in that....

Have you noticed that Ellen Muskrat hasn't gone for a ride in any of his rockets yet?

In reply to Keith Tanner :

All we need to do is call it a constructive failure.  Changing the goalposts during flight is just putting spin on the failure. I'm not saying it was a bad failure. But having to resort to blowing it up is a failure, as that's the intention of that system. It's not a bad one, as it did some good things, but it did not complete the total intended missions. 
 

A demo flight is still a test flight. 

alfadriver said:

In reply to Duke :

Sorry, they knew all of those details months and months ago. So it is a failure of a system that should be very well understood and scalable.

Again, if this was anyone other than spacex, it would be a disaster. But it's spun as a win. I don't get it. 

The stated primary goal was to clear the launchpad successfully.  Of course, there was additional flight profile in the queue for after that, should Step One be successful.

Step One was successful, as was Step Two (Max Q, survival of maximum dynamic pressure).  Step Three (second stage separation) was a failure.

I understand you don't seem to like Elon / SpaceX / whatever, but they successfully met their primary and secondary test goals, even if they didn't get any further into the flight profile than that.

It's not a complete win, but it isn't being billed as that.  It's just not a disaster, either.

In reply to alfadriver :

The goalposts didn't change before flight if you were following this test before launch. It wasn't really expected to complete the full test. Fingers crossed and best effort, yes, but there were a LOT of things flying for the first time.

A demo flight has very different expectations than a test flight. At least, it does to me. That's where we seem to disagree.

VolvoHeretic said:

bobzilla said:

In reply to Tom_Spangler (Forum Supporter) :

It's how spacex seems to do things. It seems to be working for them, but I would be a bit hesitant as a potential rider in that....

Have you noticed that Ellen Muskrat hasn't gone for a ride in any of his rockets yet?

That's because his goal with SpaceX is very different than just getting a joyride to space, unlike some other high profile billionaires. And yet, if you wanted a safe ride to the ISS,  you'd be riding SpaceX because the Falcon 9 is very reliable.

If you wanted a short suborbital hop, you might get in line behind Bezos and Branson who both rode their creations to the Karmann line. But unfortunately both of their craft are grounded due to safety problems.

alfadriver said:

Again, if this was anyone other than spacex, it would be a disaster. But it's spun as a win. I don't get it. 

NASA would have been shuttered long ago if they blew up as many rockets as they have.