totm nov 2023 SpaceX Discussion Thread

[Elthy]

11 hours ago, sevenperforce said:

The fully loaded Starship + Superheavy is over 5,000 tonnes. The impact of having or not having a 100-150 tonne payload will be an acceleration difference of 2%. Negligible.

At launch. But 100t less dry mass will have an extreme impact on delta-v, resulting in an early burnout of the second stage. Either they will have lots of fuel left (which they propably cant vent during the half orbit they are doing) or they start with less than full fuel tanks, which will be more than just 2% of the mass at liftoff.

[sevenperforce]

7 hours ago, Elthy said:

19 hours ago, sevenperforce said:

The fully loaded Starship + Superheavy is over 5,000 tonnes. The impact of having or not having a 100-150 tonne payload will be an acceleration difference of 2%. Negligible.

At launch. But 100t less dry mass will have an extreme impact on delta-v, resulting in an early burnout of the second stage. Either they will have lots of fuel left (which they propably cant vent during the half orbit they are doing) or they start with less than full fuel tanks, which will be more than just 2% of the mass at liftoff.

In either event, the outcome will be well within the system's ability to compensate. For one thing, they're only running the Raptors on Superheavy at around 90%. And they can similarly throttle down Starship to compensate, or burn to a slightly higher orbit, or dump propellant.

It's not just a half orbit. It's the equivalent of a full orbit -- a rather aggressive one -- just with a higher apogee and a perigee inside the Earth.

[tater]

 

 

[Geonovast]

An off-topic discussion regarding a topic not appropriate for this forum has been removed.  The date of the next launch attempt is nothing more than the date of the next launch attempt.  Please keep unrelated topics assigned to happenstance numbers elsewhere.

Thank you.

[tater]

58 minutes ago, Geonovast said:

An off-topic discussion

Is now even more off topic, lol:

 

[CatastrophicFailure]

Not gonna happen. Absolutely impossible. 
 

Why? I already have that day off AND will be up early. 

[tater]

 

[Little 908]

1 hour ago, tater said:

 

hype for real, even if its a few more days, it has been a few years since it started

Edited April 18, 2023 by Little 908

[tater]

 

[Motokid600]

Planning around work for this has been a roller coaster ride to say the least.

[AtomicTech]

4 hours ago, Geonovast said:

An off-topic discussion regarding a topic not appropriate for this forum has been removed.  The date of the next launch attempt is nothing more than the date of the next launch attempt.  Please keep unrelated topics assigned to happenstance numbers elsewhere.

Thank you.

It was informative while it lasted

[Pthigrivi]

Im so torn about all this. Like from a technological standpoint this is awesome but also the thing has no LAS or human survivability anywhere in its conception. Its gonna kill people and I guess thats just the price of… something? Some grifty sales pitch about mars? As an endeavor its kind of psychotic. I feel like Im rooting for Joffrey Baratheon to win a science fair. 
 

Sorry I know this is very off-message. When I say Im torn I really mean it. Again technologically its absolutely amazing. But philosophically what actually is this thing? In the last few days Ive been reading and watching a lot about Challenger and Colombia and these people all died because people in power prioritized money and position over other peoples lives. Who knows maybe lots of iteration makes starship some immaculately perfect system but I see no evidence that the folks in charge actually value human life above the pursuit of lucrative government contracts. 

Edited April 19, 2023 by Pthigrivi

[darthgently]

16 minutes ago, Pthigrivi said:

Im so torn about all this. Like from a technological standpoint this is awesome but also the thing has no LAS or human survivability anywhere in its conception. Its gonna kill people and I guess thats just the price of… something? Some grifty sales pitch about mars? As an endeavor its kind of psychotic. I feel like Im rooting for Joffrey Baratheon to win a science fair. 
 

Sorry I know this is very off-message. When I say Im torn I really mean it. Again technologically its absolutely amazing. But philosophically what actually is this thing? In the last few days Ive been reading and watching a lot about Challenger and Colombia and these people all died because people in power prioritized money and position over other peoples lives. Who knows maybe lots of iteration makes starship some immaculately perfect system but I see no evidence that the folks in charge actually value human life above the pursuit of lucrative government contracts. 

Wow.  FUD much?  I fail to see the rational foundation or available information for such an involved opinion.  But that is probably just me not being in the know on some crucial consensus

[Pthigrivi]

25 minutes ago, darthgently said:

Wow.  FUD much?  I fail to see the rational foundation or available information for such an involved opinion.  But that is probably just me not being in the know on some crucial consensus

What I mean is if you cared most of all about reducing launch costs and secondarily about securing long-term government contracts and tertiarily about about cornering the orbital delivery market and then, maybe, somewhere down the checklist you worried about human occupants reliably  surviving reentry starship is exactly what you would design. There’s no launch abort system. There’s no plan for failed belly flop or engines exploding on ascent. I mean folks asked early on when all those goofy animations rolled with starships landing on mars “where’s the radiation shielding” and dude was like “we’ll point the engines at the the sun.” Its just so frustrating to see so much intelligence directed at making money and such an obviously stupid and cavalier attitude taken towards safety and actual people’s lives.

Edited April 19, 2023 by Pthigrivi

[tater]

1 hour ago, Pthigrivi said:

Im so torn about all this. Like from a technological standpoint this is awesome but also the thing has no LAS or human survivability anywhere in its conception. Its gonna kill people and I guess thats just the price of… something? Some grifty sales pitch about mars? As an endeavor its kind of psychotic. I feel like Im rooting for Joffrey Baratheon to win a science fair.

Grifty? Be specific. I'm pretty on the record here as not being a Mars-Bro. That said, there is no grift. How would SpaceX swindle people, and why?

Step 1. Build Mars Rocket.

Step 2. ?

Step 3. Profit!

Imagine it costs $250,000 to buy a flight to Mars (per some old Musk talk). That means if they could actually get 100 people on each SS, they'd gross $25M per ship! Wow, what a grift, making 1/4 of what they could sell a F9 launch for! So smart! What clever grifters!

It's not a thing to make money, sorry. There are plenty of reasons to be against trying to colonize Mars, and in fact I can't imagine any economic case for it that closes. The only money to be made on Mars might be to sell flights to NASA for some billions—and billions that are far lower than what NASA would pay for an SLS/LockMart system (they have that cool lander and orbital Mars station concept, but that must cost... $100B? More?).

1 hour ago, Pthigrivi said:

Sorry I know this is very off-message. When I say Im torn I really mean it. Again technologically its absolutely amazing. But philosophically what actually is this thing? In the last few days Ive been reading and watching a lot about Challenger and Colombia and these people all died because people in power prioritized money and position over other peoples lives. Who knows maybe lots of iteration makes starship some immaculately perfect system

Yawn.

Starship won't see launch/EDL humans for a long time, or many flights, whichever comes first. As for survivability, what are you talking about? It would have plenty of survivability by the time they fly humans—all EDL methods have failure modes. Heat shields? All need that, SS has this, which needs to be tested, and possibly iterated—like every other TPS concept does, else you're dead (Columbia). Aero/landing? Chutes can and have failed. Need to be tested. Chutes fail, you're dead—for SS, engines fail, they're dead. Needs testing such that reliability is demonstrated. You act as if they're throwing people on this thing Friday.

Lunar Starship only has to land on the Moon, which is fairly trivial compared to Earth EDL.

My guess is that for a while crew are delivered with Dragon, then returned to Earth the same way.

1 hour ago, Pthigrivi said:

but I see no evidence that the folks in charge actually value human life above the pursuit of lucrative government contracts. 

My bold. What lucrative contracts would those be, exactly? Again, be specific.

$2.9B for HLS, which involves no Earth EDL? That's the easy mode of vertical landing for SpaceX, they do a more difficult landing every few days at this point. Also, $2.9B is not lucrative, it's chump change. There is no money to be made in space with "contracts." That's not a thing, and won't be unless some market comes into being which does not yet exist.

Edited April 19, 2023 by tater

[tater]

1 hour ago, Pthigrivi said:

What I mean is if you cared most of all about reducing launch costs and secondarily about securing long-term government contracts and tertiarily about about cornering the orbital delivery market and then, maybe, somewhere down the checklist you worried about human occupants reliably  surviving reentry starship is exactly what you would design.

Launch costs being massively lowered is an enabling technology for any interesting expansion into space, regardless of humans aboard. No reduction in cost, and human spaceflight is a niche thing forever.

Gov contracts? Like what? Sending humans to the Moon? Unless politics magically changes, NASA will not sole source this, and their sweet, sweet pork is committed to SLS for a while. Maybe that changes at some point, but if it does it will be because SS is so very much cheaper than SLS/Orion-enabled missions. Assume 10 human flights into the SLS/Orion program. Marginal cost of 2-4 billion per, plus dev cost makes the all-in cost $7-9B per flight—not counting all the not-SLS stuff for Gateway, landers, etc. SpaceX already has a cost precedent at <$2.9B (because that's for 2 landings). SpaceX would make a ton of money at $1B/flight with no SLS (Dragon for taxi service to/from Earth to LEO). In return NASA gets 4 flights a year for just the SLS budget, 5 if you count what they'd pay for each LSS flight. Wow, $4B.... chump change. By the time that happens Tesla will probably make that much in a week.

Gov contracts are never gonna be serious money. The orbital launch market is similarly small—unless SS can generate a new market into existence by low cost... but then they make less on launch. If it lowers cost, they make less money, not more.

1 hour ago, Pthigrivi said:

There’s no launch abort system. There’s no plan for failed belly flop or engines exploding on ascent. I mean folks asked early on when all those goofy animations rolled with starships landing on mars “where’s the radiation shielding” and dude was like “we’ll point the engines at the the sun.” Its just so frustrating to see so much intelligence directed at making money and such an obviously stupid and cavalier attitude taken towards safety and actual people’s lives.

Where's the radiation shielding on Orion? Oh, they wear vests, and sit on top of their food.

Again, you act as if crew is boarding on Friday. First they make it work for cargo. Then they make it work for EZ mode landing—the Moon. Way down the line EDL on Earth.

 

Edited April 19, 2023 by tater

[tater]

 

[CatastrophicFailure]

1 hour ago, Pthigrivi said:

Its just so frustrating to see so much intelligence directed at making money and such an obviously stupid and cavalier attitude taken towards safety and actual people’s lives.

No, just... no. All due respect, no.

Yes, they NEED to make money in order to fund this thing, both current and future development (we've all played KSP, right?). Since they obviously can't start with flying people on it (and very little economic case for that anyway as @tater points out), that leaves contracts. The same sort currently using the Falcons that have been funding the company all along, they're quite good at it. And everything not spent on operations goes back into R&D. It's a launch company, I guarantee you no one is "making money" off it, and best a lot of folks are simply (and rightly) living comfortably off it. The launch business is really a great way to lose money.

Cavalier attitude? I'm sorry but this is just false. I will point you to the rather involved certification process for Dragon, which was done to the satisfaction of even risk-averse NASA, and the biggest issue with it has been a busted toilet. Before anyone ever gets aboard Starship, even launching to it on Dragon, you can bet there will be an equally involved certification process with the FAA, which will involve inventing said process in the... process.

Remember, despite the incredible access us plebs have thanks to a few very dedicated content creators,  we DON'T have the whole story and don't know everything that's going on behind the scenes. As you yourself said, there's some very intelligent people working there, maybe trust them just a little based on their existing track record of accomplishments.

[tater]

 

 

[Lukaszenko]

5 hours ago, Pthigrivi said:

What I mean is if you cared most of all about reducing launch costs and secondarily about securing long-term government contracts and tertiarily about about cornering the orbital delivery market and then, maybe, somewhere down the checklist you worried about human occupants reliably  surviving reentry starship is exactly what you would design. There’s no launch abort system. There’s no plan for failed belly flop or engines exploding on ascent. I mean folks asked early on when all those goofy animations rolled with starships landing on mars “where’s the radiation shielding” and dude was like “we’ll point the engines at the the sun.” Its just so frustrating to see so much intelligence directed at making money and such an obviously stupid and cavalier attitude taken towards safety and actual people’s lives.

I'm no businessman, but even I know that killing your customers, especially en masse, is not a good business model.

Nor is blowing up their payloads.

I'm sure there are some brains at SpaceX that know this as well. This is probably why the Falcon 9 is the most reliable rocket in operation, despite not even carrying people most of the time. I'm guessing that the reason you don't hear about how safe Starship should or will be, is because this is such an obvious point that talking and focusing on it too much would only make it suspect. Kind of like if somebody tried to sell you a "vegan tomato".

Not to mention that at this stage in development, it would be a bit of a case of putting the cart before the horse. 

 

Edited April 19, 2023 by Lukaszenko

[magnemoe]

3 hours ago, CatastrophicFailure said:

No, just... no. All due respect, no.

Yes, they NEED to make money in order to fund this thing, both current and future development (we've all played KSP, right?). Since they obviously can't start with flying people on it (and very little economic case for that anyway as @tater points out), that leaves contracts. The same sort currently using the Falcons that have been funding the company all along, they're quite good at it. And everything not spent on operations goes back into R&D. It's a launch company, I guarantee you no one is "making money" off it, and best a lot of folks are simply (and rightly) living comfortably off it. The launch business is really a great way to lose money.

Cavalier attitude? I'm sorry but this is just false. I will point you to the rather involved certification process for Dragon, which was done to the satisfaction of even risk-averse NASA, and the biggest issue with it has been a busted toilet. Before anyone ever gets aboard Starship, even launching to it on Dragon, you can bet there will be an equally involved certification process with the FAA, which will involve inventing said process in the... process.

Remember, despite the incredible access us plebs have thanks to a few very dedicated content creators,  we DON'T have the whole story and don't know everything that's going on behind the scenes. As you yourself said, there's some very intelligent people working there, maybe trust them just a little based on their existing track record of accomplishments.

This, now starlink should be an nice revenue stream as it should be an huge marked if they don't mess it up. And no 5G is not an competition its the opposite, 5G gives high bandwidth in very populated places like city centers. 
Starlink works best if remote as its not to many users on the satellite. 
And this is something who is posible because lowered launch costs. 

And yes it will be quite some time until manned starship flights outside of moonship who is quite different. I don't think even recovery of second stage is fully fleshed out yet. 
Things might change, as I see it an abort system would be most relevant during landing.

[mikegarrison]

44 minutes ago, Lukaszenko said:

I'm no businessman, but even I know that killing your customers, especially en masse, is not a good business model.

Nor is blowing up their payloads.

I'm sure there are some brains at SpaceX that know this as well. This is probably why the Falcon 9 is the most reliable rocket in operation, despite not even carrying people most of the time. I'm guessing that the reason you don't hear about how safe Starship should or will be, is because this is such an obvious point that talking and focusing on it too much would only make it suspect. Kind of like if somebody tried to sell you a "vegan tomato".

Not to mention that at this stage in development, it would be a bit of a case of putting the cart before the horse. 

 

The lack of launch abort options was a serious concern about the Space Shuttle, one that ultimately did come home to rest when there was a launch failure that killed the crew.

It's a legitimate concern for Starship ever becoming crew-rated.

As best I can tell, Starship is being designed with the constraint that it could be used for landing and launch operations on Mars. What is acceptable risk on Mars (because you have no other options) is not necessarily acceptable risk on Earth.

[Lukaszenko]

48 minutes ago, mikegarrison said:

The lack of launch abort options was a serious concern about the Space Shuttle, one that ultimately did come home to rest when there was a launch failure that killed the crew.

It's a legitimate concern for Starship ever becoming crew-rated.

As best I can tell, Starship is being designed with the constraint that it could be used for landing and launch operations on Mars. What is acceptable risk on Mars (because you have no other options) is not necessarily acceptable risk on Earth.

I completely agree. I was more a refuting the notion that SpaceX is prioritizing making money over human lives. Even assuming that SpaceX's  ONLY goal is making money, the safety of its customers and reliability of its rockets is a necessary prerequisite.

[JoeSchmuckatelli]

7 hours ago, Pthigrivi said:

There’s no launch abort system

I think you are missing that this is a proof of concept vehicle program at this point. 

Further, SX has a proven record with Unmanned vehicles performing well in space so for the short term there is no problem. 

Once they move on to crew rated anything on top of Booster - I suspect that the design will have changed and matured. 

So I think your concern is premature.  Let them iterate, get cost down and the vehicles flight rated and then see what changes and where they are headed before fretting about possible human use of the craft/s

[mikegarrison]

38 minutes ago, JoeSchmuckatelli said:

I think you are missing that this is a proof of concept vehicle program at this point. 

Further, SX has a proven record with Unmanned vehicles performing well in space so for the short term there is no problem. 

Once they move on to crew rated anything on top of Booster - I suspect that the design will have changed and matured. 

So I think your concern is premature.  Let them iterate, get cost down and the vehicles flight rated and then see what changes and where they are headed before fretting about possible human use of the craft/s

Well, SpaceX is releasing videos that at least imply humans are going to be launching on trips to Mars in Starships. If this were just a bunch of people on the internet jumping to make assumptions, I would agree with you. But SpaceX themselves seem to be putting this scenario on the table, so I don't think it is at all unreasonable or premature to point out potential problems with it.

Edited April 19, 2023 by mikegarrison