SpaceX launches

CNBC (apparently) has stated 3:14 EST. They are definitely fueling.

In reply to Javelin (Forum Supporter) :

I wouldn't wait that long to tune in, we've seen some venting from the upper tank of the rocket which indicates the luanch will happen sooner than that. But of course we are all guessing.

In reply to adam525i (Forum Supporter) :

I'm watching live on the NASASpaceflight YouTube live feed.

So, is it going to land if it gets off the ground? I'm 60% that it lands successfully. 

Looks like the 3:14 pm prediction is a good one.

Boo!

Oops.

Not oops, ooops means boom. Something didn't light properly, so it shut down and the testing can continue.

It's easy to forget that the engines on Starship are revolutionary themselves, they're the only full flow staged combustion rocket engine to ever fly. There are a whole bunch of firsts being tried out here.

Sounds like a maybe in two hours for those just checking in.

I heard that the Raptor engines initiated a shutdown only 0.1 seconds before clamp release. Something about an abnormal thrust amount triggered the shutdown.

They will recycle and attempt another launch around 5:30PM EST.

Elon Musk:

Launch abort on slightly conservative high thrust limit. Increasing thrust limit & recycling propellant for another flight attempt today.

If they launch today I'm down to 40% that it lands (in one piece). Like Keith said these engines are cutting edge and getting them lit properly seems to be pretty tricky.

I've posted this video before that explains the Raptor engine, it's worth the watch and explains what is going on pretty well.

As noted on the NASASpaceflight stream, it's actually pretty impressive that these engines can do a start, shut down and then fire up again as soon as the fuel tanks are refilled. A lot of other engines require some refurbishing, and if they were solid rocket boosters there would have been a launch because they don't turn off until they burn out.

Keith Tanner said:

As noted on the NASASpaceflight stream, it's actually pretty impressive that these engines can do a start, shut down and then fire up again as soon as the fuel tanks are refilled. A lot of other engines require some refurbishing, and if they were solid rocket boosters there would have been a launch because they don't turn off until they burn out.

Yeah, that's why there was a several second delay between "main engine start" and "liftoff" on the shuttle.  They lit the SSMEs, waited a couple seconds for the thrust to stabilize so that they were confident they would work, THEN lit the SRBs.

IMHO SRBs have no place on crewed rockets.

Keith Tanner said:

Not oops, ooops means boom. Something didn't light properly, so it shut down and the testing can continue.

It's easy to forget that the engines on Starship are revolutionary themselves, they're the only full flow staged combustion rocket engine to ever fly. There are a whole bunch of firsts being tried out here.

LOL, any suggestions for a technical SNAFU?  Something less meaningful than oops.

In reply to adam525i (Forum Supporter) :

It's interesting that they call the failed landings successes- and while they did manage to lift off and get the height they wanted, the fact that the ships were destroyed means they have to make more to keep testing.  The big feature of these devices is how reusable they are, and making them not so is kind of a big deal.

alfadriver (Forum Supporter) said:

It's interesting that they call the failed landings successes- and while they did manage to lift off and get the height they wanted, the fact that the ships were destroyed means they have to make more to keep testing.  The big feature of these devices is how reusable they are, and making them not so is kind of a big deal.

These are prototype testing articles, not production spacecraft.  They're designed to allow them to develop the technology and will be thrown away once they're no longer useful.  Even if they don't crash they'll probably only get 1, maybe 2 more flights before they are discarded and SpaceX moves on to the next one.  The prototypes are far from complete, they basically only have enough systems in them to allow testing the specific goals of that unit.

Success/failure of a test depends on the test's goal, AIUI the last two prototypes crashed after the stated test goals were complete which is why they were a "success".  The landing was a stretch goal -- might as well give it a try even if they don't expect it to work because they'll learn something.

In reply to codrus (Forum Supporter) :

I understand that, but even getting ONE more test means you lost a test when the craft crashed.  And when each test is such a big deal, losing those two can't be just "oh, it was ok, it passed the test requirement".  

And given the number of successful landings, the idea that it was a stretch goal is a stretch to me.  Of all the challenges that this craft should have- landing should be something they are already good at.  So IMHO, the test plan included the test(s) for the successful landing.  While it sounds nice that the tests were successful, losing future tests is a problem.

But the landing technique is a radically new one. It's not what they're doing with the Falcons, it's a crazy skydiving bellyflop that involves relighting the engines, standing the thing on its tail and then landing. Meanwhile, you have to keep feeding fuel to the engines.

The tests include aerodynamic control during the skydive, throttle control, hovering on one engine (10k up!) and a whole host of other things. Landing is just the last thing and it's a thing that's never been done.

From a software point of view: these are cattle not pets!

In reply to alfadriver (Forum Supporter) :

As SN8 blew to pieces, SN9 was almost ready to roll out of the assembly building (in fact it was leaning on it, whoops), as SN9 blew to pieces SN10 was on the pad a couple hundred feet away.

This landing has nothing to do with Falcon's landings (which still aren't 100% successful). Different vehicle, different engines and completely different flight profile. The goal of course is to have a vehicle in one piece afterwards but based on how they are pushing these things out I don't think there was any expectation of that happening on the first flight. If it were NASA yes, they take years upon years to hopefully do it right once, SpaceX is going the other way trying to shrink the development window with some scrap stainless steel along the way.

"Cattle not pets!" I like that lol

Livestream is up for SpaceX

HELL YEAH!!!!!

Nicely done.  The enthusiasm is pretty fun to hear.

alfadriver (Forum Supporter) said:

I understand that, but even getting ONE more test means you lost a test when the craft crashed.  And when each test is such a big deal, losing those two can't be just "oh, it was ok, it passed the test requirement".  

And given the number of successful landings, the idea that it was a stretch goal is a stretch to me.  Of all the challenges that this craft should have- landing should be something they are already good at.  So IMHO, the test plan included the test(s) for the successful landing.  While it sounds nice that the tests were successful, losing future tests is a problem.

No, on any given test you have a set of things you are intending to learn.  If you learn those things then the test was a success, no matter what happens after you learn them.

As for the stretch goal, Musk said that up front before they launched.  While the experience of the Falcon 9 landings has undoubtedly contributed an enormous amount of knowledge towards how to get Starship to land, the actual systems to make it work are completely different.  Different engines with different ancillary systems, a different vehicle attitude when the engines ignite, different maneuvers that are required immediately after ignition, etc.

"they should be good at landing" is like saying that a NASCAR champ should be able to jump in an F1 car and set a competitive time.  Maybe he can eventually, but there's a lot of new stuff to learn first.

I love that the landing pad is directly beside the public road to the beach, it looks like if it tips the nose would be on the street.

Edit: I love the faint X in the sky in the top right of the picture from jets passing overhead