totm nov 2023 SpaceX Discussion Thread

[Camacha]

37 minutes ago, DerekL1963 said:

No duh.  They know exactly what went wrong - they ran out of starting fluid.  What they don't know (or haven't announced yet), and what's no doubt keeping those engineers up late tonight, is why it went wrong.  You're badly mistaken in confusing the two.

It's a marathon, not a sprint. It's about accepting failure as part of the process and working towards your goal. Frantic all-nighters with the whole team isn't a long term strategy. I have no doubt they're going to get some sleep and get together tomorrow to start figuring it out. Keeping already exhausted engineers up all night after an already intense build up to the launch isn't likely to produce the best results, even though there might be a few that can't keep themselves from poking around in the data.
 

1 hour ago, Kerbal7 said:

Losing a booster is a big deal when you are trying to bring down the cost of rocket flight to a somewhat reasonable level. It's a very big deal. You seem to have some slavish devotion to see the positive in Musk and SpaceX and spout it. Musk has been saying we are going to have people on Mars in a few years for a very long time now for PR purposes and you worshipers keep buying. The fact is Mr. Musk is nowhere close to having the capability to put people on Mars. Not-even-close.   

The engineers whose booster slammed into the sea at 300mph today will not be celebrating tonight. Far from it.

Today the first prototype of one of the most powerful rockets ever built executed its first test flight, and despite warnings that failure was likely, the payload was delivered successfully into an orbit no private company before managed. While doing this, two out of three major sections returned to Earth unharmed. Apparently, acknowledging the successful part of this highly experimental flight is having a "slavish devotion", even though both the people here, experts and and the world press all agree it's quite an achievement. Not flawless, mind, but impressive nonetheless. I'm not sure what you're trying to achieve by insulting people who recognize this achievement.

I don't think anybody thinks Musk is going to Mars any time soon either. It's obvious he'll need the BFR for that. We all know the BFR isn't going to fly any time soon. Ergo, Musk isn't going to Mars very soon. However, if you wanted to go to Mars, SpaceX seems to be on a very reasonable development path, tackling increasingly complex challenges along the way.

Edited February 7, 2018 by Camacha

[NSEP]

When is block 5 going to launch?

[Aghanim]

Hopefully SpaceX will be releasing the TLE for Roadster so that someone with a powerful enough telescope can take pictures of it

EDIT: Someone on Wikipedia puts the COSPAR ID for Tesla and searching around for that results in this: https://www.n2yo.com/satellite/?s=43205

Quote

1 43205U 18017A   18037.94189123  .00000283 -50857-6  00000+0 0  9991
2 43205  29.0185 287.3580 3404246 180.0270 180.5840  8.75540848    00

EDIT 2: TLE is for Earth orbiting objects, but Tesla is in escape trajectory, so this TLE will be useless when Tesla is far away from Earth?

Edited February 7, 2018 by Aghanim

[Josh IN SPACE]

OH MY GOD THAT WAS NUTS!!!

Was at work in my cubicle watching this go down while seeing everyone's reactions on here, but couldn't sign in.

Wish I'd taken yesterday and today off and just flown out there to watch the launch. I was sure it was gonna scrub for a week to be honest with you...

I must have looked like I was really enjoying my job with a big grin on my face, pumping my fists in the air silently.

Way to go SpaceX!

-Side note. I hope maybe there is footage to come of the core booster diving into the drink. Watching that sounds almost as entertaining as watching the actual launch.

[RizzoTheRat]

Arianne V successfully demonstrated why a full test flight with a cheapish payload rather than a paying customer is a great idea.  Even if this had been a commercial flight it would have been considered a success as the payload got to where it was intended, as a test flight and PR exercise I suspect it's been even more successful than they dared hope.

The video of the 2 boosters landing together is just stunning, hard to believe they're 70 meters tall!

2 hours ago, YNM said:

You can't continue to reuse stuff. They need repairs and replacement over time...

How reusable are they supposed to be?  I believe they've currently only reflown something like 6 of the 20+ that have been recovered.  Is that due to them just taking a while to refurbish or modifications being needed as part of the development phase.  Presumably long term there will be an intention to reuse all of them, but how many times?  Presumably they'd aim to use ones that have flown a few times before for missions where they can't recover the stage so they're only losing ones that would be scrapped anyway?

 

 

ETA:  Apparently the core stage was close enough to do some damage to the drone ship

"The centre one lit but the outer two did not and that was not enough to slow the stage down. Apparently it hit the water at 300 miles per hour and took out two of the engines on the drone ship.  We've got the footage. It sounds like some pretty fun footage, so if the cameras didn't get blown up as well then we'll put that up for, ya' know, a blooper reel. We weren't going to use that centre core [again] anyway."

Edited February 7, 2018 by RizzoTheRat

[rudi1291]

Just rewatched the stream. I said it already yesterday, but again: This launch was amazing! A bit sad that the center core didn´t make it, but it was a test, if there´s a problem its better to find it now rather than later. And to be honest, i expected more/bigger problems. Still amazed that the booster seperation worked as well as it did!

[Streetwind]

15 minutes ago, RizzoTheRat said:

How reusable are they supposed to be?  I believe they've currently only reflown something like 6 of the 20+ that have been recovered.  Is that due to them just taking a while to refurbish or modifications being needed as part of the development phase.  Presumably long term there will be an intention to reuse all of them, but how many times?

SpaceX has stated that Block 3 boosters can be flown only two or three times, whereas Block 5 boosters have "at least" ten flights in them, with the hope of pushing that higher once the actual wear and tear over many flights is better understood.

Block 5 is up and coming; not sure if they already launched one, or are planning to launch one soon. But most reflown boosters have been Block 3 so far. Most of the backlog of landed boosters they have available at this point is Block 4.

[RCgothic]

Feedback is that the side cores are in good enough condition to fly again but they won't.

[p1t1o]

God that rocket is awesome, I just wish I could stand Elon.

[Thor Wotansen]

@Kerbal7 and @DerekL1963 you have to remember that this was a proof of concept as well as a test flight.  As powerful as our aerodynamic simulations are we do not have the ability to model the entire atmospheric flight of a given rocket with 100% accuracy, and therefore, with every first flight of any rocket there is a non-trivial chance of the entire vehicle disintegrating for no apparent reason.  The fact that the vehicle delivered it's payload to the intended orbit, and in fact exceeded it's projected target by a significant amount is an incredible achievement, added to by the fact that the second stage spent a long period in the Van Allen belts being bombarded by some pretty severe radiation and was still able to preform the TME.  This has implications beyond getting pretty images of a space suite in a sports car with the Earth in the background.  Several government agencies are interested in the capability of a satellite being delivered to geostationary orbit rather than a GTO trajectory, and until now SpaceX could not offer that capability because the vehicle was untested in that radiation environment.

As a test of a launch vehicle, the flight was 100% successful, delivering it's payload to it's intended orbit.  As a test of a reusable system the flight did not quite meet it's target, however I must remind you that the Falcon Heavy core is entirely redesigned from the Falcon 9 due to structural concerns, and while a lot of their experience with landing Falcon 9s comes into play when attempting the landing of the center core, it was an entirely untested vehicle on it's maiden flight, and it is not insignificant that it only failed at the very end of the landing maneuver, after successfully completing reentry from higher speeds than ever before.  Additionally, the simultaneous landing of the side boosters in an impressive feat.  Elon mentioned in the post launch press conference, that there were concerns that the two vehicles' radars would interfere with each other and give false readings, which would of course cause some pretty explosions.  On the whole, everything after clearing the launch pad was a success, and if the successful landing of the core stage is simply a matter of increasing the amount of starting fluid or making sure the valves for said fluid don't get stuck or use too much on other ignitions, then SpaceX can expect to recover all 3 cores on the next launch.  It's easy to get annoyed at the fanboys and fangirls who shout about Elon saving the world, but don't let that annoyance with a group of people color your assessment of SpaceX's achievements.  The fact remains that 5 years ago, the landing of any first stage of a rocket was science fiction, and recovering 2/3 of the first stage of the most powerful operational rocket on the planet on it's first flight is a monumental achievement when taken in the context of spaceflight up to this point.

[YNM]

I wanted to know the coverage of this launch elsewhere, so I tried finding in google, and...

"Space Shuttle" ?!

[KSK]

5 minutes ago, Thor Wotansen said:

Stuff

That's pretty much my take on it. Great accomplishment, pity about the core stage but it was, after all, a test flight. I know that SpaceX wanted to downplay expectations with their '50% chance of success' line but I'm also prepared to believe that they were genuinely prepared for the thing to explode after take off.

It's worth noting that if there had been a proper money-earning payload on top of that rocket, that it would most likely be in the correct orbit as we speak. SpaceX would still be down one core booster but that's their problem, not the customer's. So from that point of view, the flight would have been a complete success.

As it is, apart from a problem with the core stage igniters, everything went beautifully. The static fire wasn't a fluke - 27 engines can be made to work in harmony and put a rocket into space. Max-Q - not a big problem as it turned out. Certainly not an RUD sized problem. Staging and boostback burns - went fine. None of those were guaranteed and the engines in particular were a particular concern amongst pundits (cue comparisons to the N1). Landing of flight-proven side boosters - yup. Second stage performance and multiple restarts - looked good. Six hour loiter in the van-Allen belts - didn't appear to fry anything critical or non-redundant.

And yeah - flight-proven seems an appropriate term here and not just a nice euphemism. The side boosters - igniters and all - worked just fine. The core stage was effectively an entirely new rocket that had already been extensively redesigned to cope with the stresses of being yoked to two other boosters. It's perhaps not such a great surprise that something went wrong there.

As for the threat to SpaceX's reusability plans - I don't see it. The Falcon Heavy is currently a bit of a stop-gap before BFH (granted - if BFH doesn't work out, then it becomes much less of a stop-gap) and this iteration of Falcon Heavy is using soon-to-be-deprecated hardware anyway. I have confidence that SpaceX will find the problem, figure out a solution and apply any lessons learned to Falcon Heavy Block 5. I also expect that they'll go for a soft splashdown of the core stage next time, rather than risking a droneship again.

It was a test flight. They got good data. Job done.

Stretch goals completed - the payload went where it was meant to and they got two boosters back.

[KnedlikMCPE]

Is there anyone who know if that Tesla make it to Mars orbit?

[NSEP]

2 minutes ago, KnedlikMCPE said:

Is there anyone who know if that Tesla make it to Mars orbit?

It takes several months to get to Mars, so we have to wait a while. Its on its way however.

[KSK]

45 minutes ago, KnedlikMCPE said:

Is there anyone who know if that Tesla make it to Mars orbit?

It's heading out beyond Mars orbit to the asteroid belt apparently. I'm not sure why - it doesn't really matter in the long run but I would have thought that a controlled TMI burn into a Mars transfer orbit (it was never intended to go into orbit around Mars) would have been a nice symbolic touch rather than just running the upper stage to empty and seeing how far they could get. 

Unless they really wanted to get a Pale Blue Dot shot.  

Edit: For clarity, I mean a transfer orbit as 'a heliocentric orbit with a high enough apoapsis to reach Mars had the phase angles and stuff been all correct. I don't think a Mars flyby was part of the plan either.  

Edited February 7, 2018 by KSK

[Tullius]

40 minutes ago, KnedlikMCPE said:

Is there anyone who know if that Tesla make it to Mars orbit?

It will cross orbit of Mars, but won't enter orbit around Mars, as it has expended all its fuel.

Most likely, we will lose communication with the Tesla in the next few days, as its electric power runs out.

The test went well amd the PR stunt was a complete success, but now its time for SpaceX to move on.

[Reactordrone]

7 minutes ago, Tullius said:

It will cross orbit of Mars, but won't enter orbit around Mars, as it has expended all its fuel.

Most likely, we will lose communication with the Tesla in the next few days, as its electric power runs out.

The test went well amd the PR stunt was a complete success, but now its time for SpaceX to move on.

I think it only had 12 hours of electrical power so it's probably dead by now.

Edited February 7, 2018 by Reactordrone

[Nibb31]

51 minutes ago, KnedlikMCPE said:

Is there anyone who know if that Tesla make it to Mars orbit?

It was never to planned to enter Mars orbit. It will cross Mars' orbit, but Mars will be nowhere near when it crosses.And yes, batteries will be long dead by then. It's now in solar orbit, with an apoapsis that approaches the asteroid belt and a periapsis that is close to Earth's orbit. Unless an encounter with Earth or Mars occurs, it will linger in that solar orbit forever.

It is far more likely to be recaptured by Earth one day than by Mars. It might end up coming back like J002E (the S-IVB from Apollo 12):

17 minutes ago, KSK said:

It's heading out beyond Mars orbit to the asteroid belt apparently. I'm not sure why - it doesn't really matter in the long run but I would have thought that a controlled TMI burn into a Mars transfer orbit (it was never intended to go into orbit around Mars) would have been a nice symbolic touch rather than just running the upper stage to empty and seeing how far they could get.

It was an engineering test above all, so burning until exhaustion allows them to measure the total performance of the launcher and to monitor propellant starvation situations.

[tseitsei89]

5 hours ago, DerekL1963 said:

They announced a date - and missed it by five years.  (And that's not mentioning all the interim slips during those intervening five years.)  An intentional slip is still a slip.

Falcon Heavy, like practically every other major SpaceX milestone, was late.  Period.  No amount of hand waving, smokescreens, or mirrors will change that fact.

Late yes. BUT it was still achieved. Like all other spacex milestones. We probablt wont be going to Mars in 2024 launch window but spacex will be going there later

[Streetwind]

To lighten up the mood, have some carefully selected amusements related to certain current events:

https://imgur.com/gallery/ziKpS  Consequences of forgetting to read the fine print
https://imgur.com/gallery/E4yR9  Oh well, he ended up making it work for himself
https://imgur.com/gallery/QjvMW  Meanwhile, on Earth

 

(Remember, kids: memes go on imgur, not the forums! )

[KSK]

45 minutes ago, Nibb31 said:

It was an engineering test above all, so burning until exhaustion allows them to measure the total performance of the launcher and to monitor propellant starvation situations.

Thanks. I had it in my head that total performance of the upper stage was something that they could calculate with good accuracy (so why would they need to test it?), although perhaps I'm just spoiled by KSP's simplicity in that regard.  In any case, I guess there's no substitute for confirming a calculation with actual data.

On a similar note, I found this interesting comment from Elon, on Ars Technica:

'...Fortunately, from his perspective, the launch had confirmed the company’s ability to model rocket launches on computers. “It gives me a lot of faith for our next architecture. It gives me confidence that BFR is really quite workable.”'

Genuine question - it makes total sense to me that there would be engineering test reasons for running the FH upper stage dry (or nearly so), so I'm not disputing your post,  but what sort of things are covered by 'propellant starvation situations' and what sort of things are they testing there?

[Technical Ben]

3 hours ago, RizzoTheRat said:

[snip]

 

 

ETA:  Apparently the core stage was close enough to do some damage to the drone ship

"The centre one lit but the outer two did not and that was not enough to slow the stage down. Apparently it hit the water at 300 miles per hour and took out two of the engines on the drone ship.  We've got the footage. It sounds like some pretty fun footage, so if the cameras didn't get blown up as well then we'll put that up for, ya' know, a blooper reel. We weren't going to use that centre core [again] anyway."

That actually sounds reasonable. A centre core of a first design *is* likely to be "wrong" on some degree. So re-use is a big risk, as knowing what might have shaken apart is more difficult than a second refined design after the first gives you materials/forces telemetry to spec up to.

[YNM]

8 minutes ago, KSK said:

I had it in my head that total performance of the upper stage was something that they could calculate with good accuracy (so why would they need to test it?), although perhaps I'm just spoiled by KSP's simplicity in that regard 

You still realize how hard it is to tell amount of fuel on probes do you ? Even back on Earth fuel tank gauges are rarely precision devices, airplanes don't really measure them, cars have a wide error. And that' where the fuel wouldn't come out as tiny particles floating around (or, truer to cryogenic, you've gotten yourself a pressurized tank).

11 minutes ago, Technical Ben said:

A centre core of a first design *is* likely to be "wrong" on some degree. So re-use is a big risk, as knowing what might have shaken apart is more difficult than a second refined design after the first gives you materials/forces telemetry to spec up to.

Not getting the specimen intact is a bit of a blow though. Still, I guess they can just search the right debrises.

[Technical Ben]

8 hours ago, Brotoro said:

I don't know... when you show before the launch that you are going to aim for an orbit that just touches Mars orbit, but then you put your payload into an orbit out to the asteroid belt...it kind of looks like a miss.

Hahahahaha. I think they were going for the "long shot", not the bullseye.

"Yeah, I know I missed the field goal kick in the Minnesota superbowl... but you know what..."

(•_•)

 ( •_•)>⌐■-■

 (⌐■_■)

"In two days time, that ball will reach the goal line in Maine!"

[Nefrums]

did SpaceX try a new landing procedure for the center core?

Landing is normally done on one engine,   Side boosters landed with one engine.

Last week they tried a new shorter landing burn with three engines for soft splashdown on a expendable launch.

Now we hear that the core failed to land because only one out of three engines started...

 

 

 

Edited February 7, 2018 by Nefrums