Jump to content

SpaceX Discussion Thread


Skylon

Recommended Posts

6 minutes ago, Exoscientist said:

 

 SpaceX still not doing full thrust, full flight duration static fires for either stage.

  Robert Clark

I may be wrong but they aren't doing full flight full thrust static fires for Falcon 9 either.

Link to comment
Share on other sites

3 hours ago, Exoscientist said:

 SpaceX still not doing full thrust, full flight duration static fires for either stage.

Because that would be stupid.

<clarification> This would be stupid because they would need to build entirely different facilities, and the testing would involve different—and often worse—risks than flight testing. For all that cost/trouble, there are still test regimes that only actual flight can provide.

 

Edited by tater
Link to comment
Share on other sites

8 minutes ago, Cuky said:

I may be wrong but they aren't doing full flight full thrust static fires for Falcon 9 either.

They did, though.

And as part of a series of many (I think they fired this one 8 times but it has been many years since I learned that so I might be wrong) post flight static fires to characterize reuse:

 

 

Link to comment
Share on other sites

1 minute ago, Ultimate Steve said:

And as part of a series of many (I think they fired this one 8 times but it has been many years since I learned that so I might be wrong) post flight static fires to characterize reuse:

They have a test stand capable of doing that for F9.

They have not done so at the pad, because a failure presents a scheduling risk. Last F9 pad failure had the pad out for ~6 months, right?

Also, in the case of the testing on landed boosters, they did not yet have Starlink, so they would have had to have reflown with a customer payload. They needed to demonstrate it was safe for payloads. had Starlink been a thing, I bet they would have put it on the pad and flown Starlink as the test (just as they do with flight leader boosters now.

Link to comment
Share on other sites

5 minutes ago, tater said:

They have a test stand capable of doing that for F9.

They have not done so at the pad, because a failure presents a scheduling risk. Last F9 pad failure had the pad out for ~6 months, right?

Also, in the case of the testing on landed boosters, they did not yet have Starlink, so they would have had to have reflown with a customer payload. They needed to demonstrate it was safe for payloads. had Starlink been a thing, I bet they would have put it on the pad and flown Starlink as the test (just as they do with flight leader boosters now.

I was not commenting on the validity of doing full duration static fires for Starship, I was just pointing out that full duration static fires were an important part of Falcon 9 and Falcon 9R's development cycles.

But since you brought it up, all else kept equal, I would love to see full duration Starship and Super Heavy static fires, as there is some amount that can be learned from them. However, all is not equal, as SpaceX's land situation makes that more trouble than it is worth.

Edit: I worded that a bit passive aggressively by accident, it is not meant to be passive aggressive.

Edited by Ultimate Steve
Link to comment
Share on other sites

Again, regarding the notional full thrust, full duration static fire nonsense, in the case of the IFT issues, what would either have gained?

Full thrust, full duration fire of booster? If it goes like the flight, it simply works and is nominal—except that the pad takes minutes of abuse instead of seconds, so the pad is toast for months, and maybe wrecked worse than IFT-1. Also, any failure that happened (assuming it went differently than actual flight since conditions != flight) is a possible pad-wrecking event (at the very least). Might need tanked ship on top to even try, bigger boom if trouble. Assuming nominal SF, IFT-2 happens—and SH still blows up after flip, because SF taught nothing at all about that that failure mode.

Full thrust, full duration of ship? If it went exactly as IFT-2 went, then it is nearly full duration, then explodes on the ground. The test stand is low, and it might have wrecked that long before full duration reached. FOD could RUD the ship. So yeah, entirely stupid unless they build some new facility. If the forces on the vehicle are different on the ground than in space where it actually failed, maybe it proceeds nominally, teaching them nothing about the actual failure (which would then happen in flight as it did).

8 minutes ago, Ultimate Steve said:

Edit: I worded that a bit passive aggressively by accident, it is not meant to be passive aggressive.

My post was more underlining what you said, and saying F9 is not SS/SH, not meant to be taken the wrong way either, we're on the same page for sure.

LOOONG booster SF

Edited by tater
Link to comment
Share on other sites

29 minutes ago, Moritz Space said:

This one kicked up way more dirt, during the booster 9 static fires with deluge the cloud was purely white. Could be because it was a longer static fire tho.

Looks similar to me.

I think its just camera placement that makes Booster-9 look whiter.

Did all 33 ignite?

Edited by Royalswissarmyknife
Link to comment
Share on other sites

19 minutes ago, Moritz Space said:

All 33 engines, it just seemed weird that 2 seconds into the burn it's basically all dirt and no water.

My guess is the water is probably being near-instantaneously vaporised and steam is transparent. It'll still cool the pad. And I think the reddish colour is nitrogen dioxide from the exhaust impinging on air rather than dirt. There's just not that much dirt to blast off a steel pad.

Link to comment
Share on other sites

1 hour ago, RCgothic said:

My guess is the water is probably being near-instantaneously vaporised and steam is transparent. It'll still cool the pad. And I think the reddish colour is nitrogen dioxide from the exhaust impinging on air rather than dirt. There's just not that much dirt to blast off a steel pad.

Looks more dirt color to me, but not huge clouds. Was BC experiencing a dry spell at the time? The exhaust blasting over the dirt of the surrounding areas could raise some dust…

Link to comment
Share on other sites

There was another Starship debate over on a Discord server today, as seems to happen every couple days like clockwork, and I came away from it with somewhat of a new perspective on the Starship program.

Many of the criticisms of Starship ultimately come down to the idea that it is too ambitious, that SpaceX has bitten off more than they can chew here. Well, that and taking off the cuff remarks by Elon (for example 1m per flight, 1000 passengers in p2p) as gospel and using them to show why the program is obviously stupid and the whole thing is a scam.

But the first one is more interesting and what I thought about a lot today.

Ignore HLS for a second, I'll talk about that later.

I think a lot of people would have liked to see SpaceX originally take (or pivot to) a more conservative approach to a next generation launch vehicle as a stepping stone to a fully and rapidly reusable launch vehicle rather than skipping straight to something with Starship levels of ambition. Like, for example, a fully reusable but not rapidly reusable vehicle, or a very large partially reusable vehicle.

But why?

The obvious answer is that it allows them to create something that blows Falcon out of the water for considerably less effort than Starship would take.

...But why?

They have the market completely cornered. Nobody can compete with Falcon, even discounting Starlink. Everyone except possibly Blue Origin and Relativity is stuck trying to create a rocket marginally competitive with what Falcon 9 was a few years ago. Serious competition is at least 10 years away. SpaceX doesn't need to do a thing to completely dominate the space industry for the foreseeable future. They can sit on their hands, maybe make Falcon block 6 if Relativity is looking threatening enough in a few years time. Basically do what ULA did.

What could they do with a Falconlike SHLV that they could not do with Falcon? Large stations if anyone was interested, maybe small scale medium-high cost Moon missions, being the de facto Artemis launch vehicle. But not much that is commercially viable. Not many people are going to pay 120 million for 100 tons to orbit. There would be a market, but as we are seeing with Falcon Heavy, not a huge market.

SpaceX does not want to launch a handful people to the Moon for tens of billions of dollars. They don't want to sit on their hands and accumulate wealth. They do not want to keep making minor improvements to Falcon 9 forever.

Whether or not you agree with this goal, SpaceX wants to create a self sustaining city on Mars, or at least, create some of the prerequisite technologies required for that to happen.

It is not a financial goal. It is an emotional goal. SpaceX is fundamentally an emotionally motivated company, and while finances can't be ignored, they are a means to an end. If money was the primary goal, Elon would have created sensible businesses with the PayPal money. instead, SpaceX was created out of spite for the Russians and frustration with the state of the industry. Since then, they have plastered windows on things with no business having windows on them (Cargo Dragon, I4 dome, doubling down on Starship having a huge window), dragged the space industry, kicking and screaming, into the 21st century, with many of the major advancements financed on their own dime, made Dragon 2, their spacesuits, the crew access arm, the launch tower, and much more look stylish and cool (depends on taste), arguably at the expense of a small amount of functionality, and strapped a meme payload to what was at the time the most capable operational rocket in the world.

I rewatched the IAC 2016 talk today, and while almost all of the details have changed, the core architecture has remained the same. That talk laid it out clear, this core architecture was designed with Mars in mind. In order to create a self sustaining city on Mars under reasonable economic conditions, a rapidly and fully reusable vehicle must be mass produced, and it must use propellants practical to produce on Mars, and orbital refilling must be utilized.

While an incremental approach to developing such a system does have some merits, if there is a proper time to dive in headfirst into the onslaught of engineering challenges associated with such a ridiculously lofty goal, it is while they are a decade ahead of everyone else. In order to succeed, everything known about rocket building needs to be challenged.

Anything short of a high performance mass producible rapidly and fully reusable rocket is not an acceptable stopping point, and SpaceX has made that clear with how often they threw out things that weren't working. They tested every assumption about rocket development made to date, knowing full well most of them would be reinforced, but a few would give way to unexplored potential. They threw out carbon fiber after investing a ton of money into the hardware to produce 9 and 12 meter tanks. They threw out the Florida starship site (for now at least). They made a water tower fly, and then threw out the next six prototypes for not being good enough. They built or partially built 26 starships and 3 boosters before getting something that might get to orbit, each of which had major changes from the previous, and then threw B4/S20 out practically on the eve of flight. They tried a new launch pad, and when that didn't work, they threw it out and tried something else. They tried a new form of staging, and when that didn't work, they threw it out and tried hot staging.

They tried hydrolox Raptor, and it didn't work, they threw it out. Large scale ITS Raptor, thrown out. Raptor 1, 1.5, etcetera, thrown out. Raptor 2, on its way out because Raptor 3. There's even been talk of a different engine altogether. They have produced hundreds of Raptors by now and they haven't even gotten to orbit, that's more than the total production of most other rocket engines.

ITS re entry configuration, thrown out. Two strakes, thrown out. Tripod with two flaps and a rudder, thrown out. Body flaps, modified numerous times.

Initial tiles, thrown out. Bare metal, thrown out. Transpiration cooling, thrown out. Back to tiles because that might actually be the best option, several iterations, throwing them out until they are good enough.

Can't land on the launch mount? Can't crane a ship from a landing pad to the launch pad fast enough to colonize Mars? Throw it out, try landing directly in the crane.

They are pushing the envelope in all directions trying to find anything that will get them closer to their goal and they can and will throw out any design, no matter how firmly entrenched, if it falls short of their goals. They have created the largest satellite constellation ever (okay, if you're gonna be that guy, project West Ford was indeed way bigger) just to finance the rate at which they throw stuff away. Even that satellite constellation is designed to be thrown away and replaced every five years.

This whole time, also pioneering the early stages of mass production necessary to make the city on Mars a reality.

But this city can't be built alone. A rocket such as what Starship aims to be is a prerequisite for a Mars colony, but not sufficient on its own. So every so often, SpaceX will put Starship out there to get people thinking about what such a revolutionary rocket could do in fields it isn't even optimized for. A Moon base, gigantic space stations, crewed missions to the moons of Jupiter, probes ejected from Earth at insane speeds with refueled expendable upper stages, and even point to point. Some of these are more realistic than others. If enough people start thinking about what this could do, some of them will start trying to make it a reality, and some of them might just end up producing Mars hardware in a few decades time.

Then, SpaceX decided to go "Hey, NASA, Starship can also be used as a Moon lander!" And in a move that was unexpected to most external observers, and may have even been unexpected internally, NASA, strapped for cash and with the only other status quo choices being "expensive consortium led by a company with no orbital experience" and "oopsie daisy, negative mass moment", saw a chance for an incredibly radical future, and went "Okay. You have four years. Show us what you can do." 

Of course, this is where it all went a little sideways. You can fiddle around with your revolutionary side project all you want when your only limiting factor is how long it takes other space companies to catch up with you. There are no customers to complain when it takes twice as long as planned, or keeps blowing up over and over and over again.

While HLS has been great for emphasizing Starship's legitimacy and getting even more people thinking about it, now SpaceX can't just keep throwing stuff out ad nauseum, it actually has to deliver results in a reasonable timeframe. Granted, some of this is the government's fault, selecting a lander in 2021 and expecting a landing in 2024 was never a realistic goal no matter who is doing the design. But now, a program with the single constraint of "Get lots of stuff to Mars, toss away everything that can't do that" has to be made to support the most important human spaceflight mission in decades in relatively short order. It must be safe and with a relatively frozen design, and the tankers must be produced and rapidly launched with not much more tweaking.

I don't know yet whether the added cash and legitimacy is outbalanced by the conflicting requirements. These conflicting requirements seem to be where a lot of the conflict is coming from. Since HLS, Starship is both a vehicle that needs to be chaotic in the near term in order to be revolutionary in the long term, and stable in the near term in order to get us back to the Moon.

I don't know if they will make it to Mars, much less build a city, but if anyone can do it in the next hundred years, it is probably going to be them, and they are not going to stop trying to reach that goal until they go bankrupt or the CEO dies and doesn't get replaced with a like minded person.

 

That was a lot more than I intended to write. TLDR:

SpaceX is emotionally/ideologically motivated.

Their ultimate goal is to colonize Mars.

If their goal is to make money and remain competitive, they already have that, no reason for something Starship level.

Something in between Falcon and Starship also does not make sense if their goal is merely to remain competitive.

Starship makes sense viewed through the Mars lens, its other applications are byproducts. I suspect long term an optimized Lunar architecture will look a lot different.

SpaceX will not design themselves into something that cannot be evolved into a rocket capable of creating a city on Mars.

This means a lot of throwing out stuff that doesn't work, pushing boundaries, and lots of failures.

Starship won the HLS contract, which is not a contract you want to have rapid iteration, boundary pushing, and frequent failures on.

The two conflicting aspirations for what Starship is supposed to be are causing some amount of conflict and debate.

 

 

In the time it took me to write that, the news that the ship firing today was a single engine maneuvering burn test arrived. This is completely unrelated to the above wall of text, but given how small LEO maneuvers will be (I'd guess this is simulating a de-orbit burn), that static fire might have actually been full mission duration.

Link to comment
Share on other sites

9 hours ago, Exoscientist said:

 I’m making a serious charge here. I’m suggesting SpaceX knows the Raptor is unreliable and is obscuring that fact both from the NASA and the American public.

No, you're making that conclusion first, and then trying to find whichever flimsy pieces of evidence or erroneous methodologies you can come up with to defend it. Those pieces of "evidence" have been unmasked as bogus, and the methodologies you try to apply are extremely lacking. This has been shown every single time, by people with way more patience than I have. It includes repeatedly comparing the Raptor to engines, components, or rockets that do not even exist.

I suggest to take a step back and review what you're doing here. If neither the data, the background theory, nor the methodology hold any water, why should you try to defend the conclusion time and time again, usually from scratch after the last attempt was torn to pieces?

Link to comment
Share on other sites

55 minutes ago, Ultimate Steve said:

There was another Starship debate over on a Discord server today, as seems to happen every couple days like clockwork, and I came away from it with somewhat of a new perspective on the Starship program.

Many of the criticisms of Starship ultimately come down to the idea that it is too ambitious, that SpaceX has bitten off more than they can chew here. Well, that and taking off the cuff remarks by Elon (for example 1m per flight, 1000 passengers in p2p) as gospel and using them to show why the program is obviously stupid and the whole thing is a scam.

But the first one is more interesting and what I thought about a lot today.

Ignore HLS for a second, I'll talk about that later.

I think a lot of people would have liked to see SpaceX originally take (or pivot to) a more conservative approach to a next generation launch vehicle as a stepping stone to a fully and rapidly reusable launch vehicle rather than skipping straight to something with Starship levels of ambition. Like, for example, a fully reusable but not rapidly reusable vehicle, or a very large partially reusable vehicle.

But why?

The obvious answer is that it allows them to create something that blows Falcon out of the water for considerably less effort than Starship would take.

...But why?

They have the market completely cornered. Nobody can compete with Falcon, even discounting Starlink. Everyone except possibly Blue Origin and Relativity is stuck trying to create a rocket marginally competitive with what Falcon 9 was a few years ago. Serious competition is at least 10 years away. SpaceX doesn't need to do a thing to completely dominate the space industry for the foreseeable future. They can sit on their hands, maybe make Falcon block 6 if Relativity is looking threatening enough in a few years time. Basically do what ULA did.

What could they do with a Falconlike SHLV that they could not do with Falcon? Large stations if anyone was interested, maybe small scale medium-high cost Moon missions, being the de facto Artemis launch vehicle. But not much that is commercially viable. Not many people are going to pay 120 million for 100 tons to orbit. There would be a market, but as we are seeing with Falcon Heavy, not a huge market.

SpaceX does not want to launch a handful people to the Moon for tens of billions of dollars. They don't want to sit on their hands and accumulate wealth. They do not want to keep making minor improvements to Falcon 9 forever.

Whether or not you agree with this goal, SpaceX wants to create a self sustaining city on Mars, or at least, create some of the prerequisite technologies required for that to happen.

It is not a financial goal. It is an emotional goal. SpaceX is fundamentally an emotionally motivated company, and while finances can't be ignored, they are a means to an end. If money was the primary goal, Elon would have created sensible businesses with the PayPal money. instead, SpaceX was created out of spite for the Russians and frustration with the state of the industry. Since then, they have plastered windows on things with no business having windows on them (Cargo Dragon, I4 dome, doubling down on Starship having a huge window), dragged the space industry, kicking and screaming, into the 21st century, with many of the major advancements financed on their own dime, made Dragon 2, their spacesuits, the crew access arm, the launch tower, and much more look stylish and cool (depends on taste), arguably at the expense of a small amount of functionality, and strapped a meme payload to what was at the time the most capable operational rocket in the world.

I rewatched the IAC 2016 talk today, and while almost all of the details have changed, the core architecture has remained the same. That talk laid it out clear, this core architecture was designed with Mars in mind. In order to create a self sustaining city on Mars under reasonable economic conditions, a rapidly and fully reusable vehicle must be mass produced, and it must use propellants practical to produce on Mars, and orbital refilling must be utilized.

While an incremental approach to developing such a system does have some merits, if there is a proper time to dive in headfirst into the onslaught of engineering challenges associated with such a ridiculously lofty goal, it is while they are a decade ahead of everyone else. In order to succeed, everything known about rocket building needs to be challenged.

Anything short of a high performance mass producible rapidly and fully reusable rocket is not an acceptable stopping point, and SpaceX has made that clear with how often they threw out things that weren't working. They tested every assumption about rocket development made to date, knowing full well most of them would be reinforced, but a few would give way to unexplored potential. They threw out carbon fiber after investing a ton of money into the hardware to produce 9 and 12 meter tanks. They threw out the Florida starship site (for now at least). They made a water tower fly, and then threw out the next six prototypes for not being good enough. They built or partially built 26 starships and 3 boosters before getting something that might get to orbit, each of which had major changes from the previous, and then threw B4/S20 out practically on the eve of flight. They tried a new launch pad, and when that didn't work, they threw it out and tried something else. They tried a new form of staging, and when that didn't work, they threw it out and tried hot staging.

They tried hydrolox Raptor, and it didn't work, they threw it out. Large scale ITS Raptor, thrown out. Raptor 1, 1.5, etcetera, thrown out. Raptor 2, on its way out because Raptor 3. There's even been talk of a different engine altogether. They have produced hundreds of Raptors by now and they haven't even gotten to orbit, that's more than the total production of most other rocket engines.

ITS re entry configuration, thrown out. Two strakes, thrown out. Tripod with two flaps and a rudder, thrown out. Body flaps, modified numerous times.

Initial tiles, thrown out. Bare metal, thrown out. Transpiration cooling, thrown out. Back to tiles because that might actually be the best option, several iterations, throwing them out until they are good enough.

Can't land on the launch mount? Can't crane a ship from a landing pad to the launch pad fast enough to colonize Mars? Throw it out, try landing directly in the crane.

They are pushing the envelope in all directions trying to find anything that will get them closer to their goal and they can and will throw out any design, no matter how firmly entrenched, if it falls short of their goals. They have created the largest satellite constellation ever (okay, if you're gonna be that guy, project West Ford was indeed way bigger) just to finance the rate at which they throw stuff away. Even that satellite constellation is designed to be thrown away and replaced every five years.

This whole time, also pioneering the early stages of mass production necessary to make the city on Mars a reality.

But this city can't be built alone. A rocket such as what Starship aims to be is a prerequisite for a Mars colony, but not sufficient on its own. So every so often, SpaceX will put Starship out there to get people thinking about what such a revolutionary rocket could do in fields it isn't even optimized for. A Moon base, gigantic space stations, crewed missions to the moons of Jupiter, probes ejected from Earth at insane speeds with refueled expendable upper stages, and even point to point. Some of these are more realistic than others. If enough people start thinking about what this could do, some of them will start trying to make it a reality, and some of them might just end up producing Mars hardware in a few decades time.

Then, SpaceX decided to go "Hey, NASA, Starship can also be used as a Moon lander!" And in a move that was unexpected to most external observers, and may have even been unexpected internally, NASA, strapped for cash and with the only other status quo choices being "expensive consortium led by a company with no orbital experience" and "oopsie daisy, negative mass moment", saw a chance for an incredibly radical future, and went "Okay. You have four years. Show us what you can do." 

Of course, this is where it all went a little sideways. You can fiddle around with your revolutionary side project all you want when your only limiting factor is how long it takes other space companies to catch up with you. There are no customers to complain when it takes twice as long as planned, or keeps blowing up over and over and over again.

While HLS has been great for emphasizing Starship's legitimacy and getting even more people thinking about it, now SpaceX can't just keep throwing stuff out ad nauseum, it actually has to deliver results in a reasonable timeframe. Granted, some of this is the government's fault, selecting a lander in 2021 and expecting a landing in 2024 was never a realistic goal no matter who is doing the design. But now, a program with the single constraint of "Get lots of stuff to Mars, toss away everything that can't do that" has to be made to support the most important human spaceflight mission in decades in relatively short order. It must be safe and with a relatively frozen design, and the tankers must be produced and rapidly launched with not much more tweaking.

I don't know yet whether the added cash and legitimacy is outbalanced by the conflicting requirements. These conflicting requirements seem to be where a lot of the conflict is coming from. Since HLS, Starship is both a vehicle that needs to be chaotic in the near term in order to be revolutionary in the long term, and stable in the near term in order to get us back to the Moon.

I don't know if they will make it to Mars, much less build a city, but if anyone can do it in the next hundred years, it is probably going to be them, and they are not going to stop trying to reach that goal until they go bankrupt or the CEO dies and doesn't get replaced with a like minded person.

 

That was a lot more than I intended to write. TLDR:

SpaceX is emotionally/ideologically motivated.

Their ultimate goal is to colonize Mars.

If their goal is to make money and remain competitive, they already have that, no reason for something Starship level.

Something in between Falcon and Starship also does not make sense if their goal is merely to remain competitive.

Starship makes sense viewed through the Mars lens, its other applications are byproducts. I suspect long term an optimized Lunar architecture will look a lot different.

SpaceX will not design themselves into something that cannot be evolved into a rocket capable of creating a city on Mars.

This means a lot of throwing out stuff that doesn't work, pushing boundaries, and lots of failures.

Starship won the HLS contract, which is not a contract you want to have rapid iteration, boundary pushing, and frequent failures on.

The two conflicting aspirations for what Starship is supposed to be are causing some amount of conflict and debate.

 

 

In the time it took me to write that, the news that the ship firing today was a single engine maneuvering burn test arrived. This is completely unrelated to the above wall of text, but given how small LEO maneuvers will be (I'd guess this is simulating a de-orbit burn), that static fire might have actually been full mission duration.

Thanks for taking the time to write out this post. It gave me a new perspective of the starship program that I never really even thought of. :D

 

Link to comment
Share on other sites

8 hours ago, Exoscientist said:

SpaceX still not doing full thrust, full flight duration static fires for either stage.

Yes, SLS got a full-duration static fire of the core stage. They also had full duration (as if there's any other kind with solids) static firings of a single SRB at a time. They never did or could do any kind of static fire of the entire stack. That is what you are expecting SpaceX to do. Imagine the size and expense of the facility could could handle a full-duration Superheavy static fire. The engineering challenge would almost be greater than the entire Starship program itself! Yes, new F9 cores get a full-mission-duration static at McGregor before entering service, but that's nearly an order of magnitude smaller. (4900 tons vs 550 tons GLOW). 

Edited by StrandedonEarth
Link to comment
Share on other sites

1 hour ago, Ultimate Steve said:

SNIP

Yes.

As I have said before, anyone looking at SpaceX and calibrating their opinion to some sort of business model is mistaken, they are trying to make the capability to colonize Mars. You don't have to agree with that—but that's their goal. There is not money to be made in launch at a level that is meaningful, the market is chump change.

28 minutes ago, StrandedonEarth said:

Yes, SLS got a full-duration static fire of the core stage. They also had full duration (as if there's any other kind with solids) static firings of a single SRB at a time. They never did or could do a any kind of static fire of the entire stack. That is what you are expecting SpaceX to do. Imagine the size and expense of the facility could could handle a full-duration Superheavy static fire. The engineering challenge would almost be greater than the entire Starship program itself! Yes, new F9 cores get a full-mission-duration static at McGregor before entering service, but that's an nearly order of magnitude smaller. (4900 tons vs 550 tons GLOW)

Or a facility to do a static fire of the entire SLS stack. SLS was in fact never static fired. Remember that the issue with Ares V was that RS-68 could not deal well with multiple engines AND the proximity of the SRBs from a heating standpoint—why didn't NASA test the core AND the SRBs? This notion of full duration static fire is silly.

Link to comment
Share on other sites

7 hours ago, tater said:

Not sure why irrelevant dead guy matters.

What you said was basically Korolev’s justification for not doing static fires with the N1’s first stage.

Extensive ground testing is part of why the Saturn V was so successful compared to N1.

However, I personally don’t think this rules out the use of the “artillery method” of development (basically firing off a bunch of “rounds” (rockets) over and over again) for SpaceX.

For one thing, SpaceX is not in a race with anyone, and the US government has also claimed it is not racing anyone (well, China) back to the Moon. Or at least Bridenstine said that. But anyways, there is no imperative to meet a certain date like Apollo or N1 had to, and also importantly, SLS’ own long lead times give Starship plenty of time to mature before Artemis III comes around.

And finally, SpaceX as a whole is pretty onboard with Starship. There isn’t a confidence and funding crisis like Korolev and Mishin faced when the Soviet government began asking questions about the successive failures.

Of course, that applies to Starship as an SHLV, not HLS. I’m not sure if NASA is concerned with the failures or not (probably no).

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...