[New] Space Launch System / Orion Discussion Thread

[RCgothic]

150t with full reuse is *vastly* more than 68t expendable.

[kerbiloid]

38 minutes ago, sevenperforce said:

Nope, they don't disassemble and recertify and reassemble each Falcon 9 booster between flights. 

If they don't reassemble them (idk why are you sure), then they depend on the hardware deprecation process even more.

In this case they have rely on the pre-calculated flight number while the accumulated deformations do not affect the rocket reliability beyond the appropriate risk.

45 minutes ago, sevenperforce said:

That's nonsense.

That nonsense was being applied to the crew-rated Shuttles, which were partially disassembled between the flights and even exchanging with their propulsion systems.

Let alone their SRB which were a set of refillable sections, and the on last flight one of them was using a skirt from the first flight.

49 minutes ago, sevenperforce said:

There is inspection, yes -- mostly weld x-rays and the like -- but there is virtually no refurbishment.

Engines aren't welded to the tanks. And they need a check, too.

50 minutes ago, sevenperforce said:

SpaceX currently has a fleet of 18 boosters. To achieve 50 launches in 2022 (more than the total number of successful orbital launches by the entire United States in 2021), they would only need to fly each booster 2-3 times, meaning that there is no need for them to shorten turnaround time to something lower than 4-6 months. That's just business.

The business is when a vehicle doesn't wait several months between flights.

Plane sat, plane ate, plane flew away.

The several month long interval isn't applied without a reason. And the only reason is the interflight servicing.

54 minutes ago, sevenperforce said:

To your point about planes: commercial aircraft receive an inspection that goes over hundreds of individual points between each flight.

This inspection lasts for several hours between the passenger check-ins.

55 minutes ago, sevenperforce said:

inspection and refurbishment every 20-24 months

After several thousands of flights. Not between several of them.

56 minutes ago, sevenperforce said:

No, that is not how vehicle reliability works. By that logic, every month of flight by a commercial airliner decreases her reliability enough to make them unsafe even for cargo by the 20-month mark

No, by this logic the interval is set exactly by the calculated amount of rounds before the accumulated deformations can decrease the part reliability and make the flight unsafe.

And it's not just a check, it's check and repair, with replacement of the parts which became unreliable.

1 hour ago, sevenperforce said:

14 hours ago, kerbiloid said:

SS/SH currently looks not more reliable than Falcon is.

And this analysis is based on...what exactly?

On zero flights performed.

Falcon has more than zero.

So, unlike Falcon, SH/SS hasn't proven its ability to  perform more than zero flights.

1 hour ago, sevenperforce said:

14 hours ago, kerbiloid said:

Its lifespan unlikely can reach more than several flights

I'm assuming this is some kind of heuristic...

It's based on the fact that still no Falcon has flown more than ten times, the fact that almost all known rocket designs set ten rounds as the desired value, the fact that the Shuttle engines performed up to 9 flights each (and the Energy's RD-0120 was certified for 10 as well), and the fact that the Shuttles reusability costed 0.5 .. 1 bln USD per flight and needed the partial reassembly.

Also on the ratio of the green and orange bands after just a atmospheric hop at 2 km/s speed.

1 hour ago, sevenperforce said:

Ah, yes. 150 tonnes is not much greater than 68 tonnes.

Nothing has proven its ability to lift 150 t in reusable version.

Actually, yet even 0 t in any version.

As I have shown in the SpX thread, unlikely its reusable version capability is greater than 60 t, but this doesn't matter at this point, before they have flown  at least once.

1 hour ago, sevenperforce said:

Even if an individual Starship could not be flown more than 5 times

Let it do that at least once for the beginning.

1 hour ago, RCgothic said:

150t with full reuse is *vastly* more than 68t expendable.

200 t is even better. Or 500. Why not declare more?

[sevenperforce]

50 minutes ago, RCgothic said:

150t with full reuse is *vastly* more than 68t expendable.

Indeed. 150 tonnes to LEO (or 100 tonnes to a useful orbit) is a sea change, especially given that Falcon Heavy can't actually even take a 68-tonne monolithic payload anywhere given the fairing size and PAF limitations. Apart from Falcon Heavy (and the super-low-flight-rate SLS), the most capable rockets in the world are the Long March 5, the Proton, the Falcon 9, and Delta IV Heavy, all in the 20-25 tonne payload range. So we're talking about a rocket with 4-7 times the monolithic launch capability of the best commercial rockets on the planet.

As Elon said, the marginal cost of each launch will be in the $2-3M range, maybe even as low as $1M, and so the actual cost of each launch after factoring in fixed cost and vehicle amortization will be less than $10M. We can safely assume that his amortization estimate is based on his knowledge of SS/SH's capabilities in comparison to Falcon 9. But even if he is off by a whole order of magnitude when it comes to the reusability of SS/SH, that's still on the order of $100M for a 150-tonne launch capability. Absolute and overwhelming sea change.

[kerbiloid]

We should not forget Nexus and SeaDragon.

They have performed exactly same amount of flights as Starship did to the date, but are much more capable.

[sevenperforce]

Just now, kerbiloid said:

If they don't reassemble them (idk why are you sure), then they depend on the hardware deprecation process even more.

In this case they have rely on the pre-calculated flight number while the accumulated deformations do not affect the rocket reliability beyond the appropriate risk.

Engines aren't welded to the tanks. And they need a check, too.

SpaceX has stated that they no longer remove the engines from boosters between launches unless the telemetry and other data suggest a problem with one of the engines.

That's the great thing about engines which can be fired over and over again. They can just ship the booster back home, x-ray the welds, lift it upright, and static fire the engines to make sure everything is working properly. That's an operationally reusable rocket.

The "ten flight" target is not a pre-calculated flight number. It is the target, and we have seen that they are meeting that target in operation. There is no evidence that there is any substantial difference in risk between a rocket on its first reflight and a rocket on its ninth reflight.

Just now, kerbiloid said:

That nonsense was being applied to the crew-rated Shuttles, which were partially disassembled between the flights and even exchanging with their propulsion systems.

Let alone their SRB which were a set of refillable sections, and the on last flight one of them was using a skirt from the first flight.

Why would you draw a comparison between the STS, with engines that couldn't even be relit without extensive servicing, to a rocket that can literally launch and land and static fire and relaunch?

Just now, kerbiloid said:

Quote

SpaceX currently has a fleet of 18 boosters. To achieve 50 launches in 2022 (more than the total number of successful orbital launches by the entire United States in 2021), they would only need to fly each booster 2-3 times, meaning that there is no need for them to shorten turnaround time to something lower than 4-6 months. That's just business.

The business is when a vehicle doesn't wait several months between flights.

Plane sat, plane ate, plane flew away.

The several month long interval isn't applied without a reason. And the only reason is the interflight servicing.

No, it isn't. I just gave you the math. There is no business case for accelerating turnaround if your fleet is large enough that you don't need to accelerate turnaround. If your supply significantly exceeds demand, there is no reason to expend extra resources on accelerating turnaround.

Just now, kerbiloid said:

It's based on the fact that still no Falcon has flown more than ten times. . .

Oh, except that Booster 1051 has.

Just now, kerbiloid said:

. . . the fact that almost all known rocket designs set ten rounds as the desired value. . .

Almost all known rocket designs are limited to a single flight. What are you talking about?

Just now, kerbiloid said:

. . . the fact that the Shuttle engines performed up to 9 flights each (and the Energy's RD-0120 was certified for 10 as well), and the fact that the Shuttles reusability costed 0.5 .. 1 bln USD per flight and needed the partial reassembly.

The Shuttle Engines couldn't perform even a single relight without a complete servicing overhaul, let alone a reflight. The engines on Falcon 9 fire up to five times per flight without any inspection at all and can be reflown with only minimal inspection and no significant servicing. This just emphasizes why your comparison doesn't make sense.

Just now, kerbiloid said:

1 hour ago, RCgothic said:

150t with full reuse is *vastly* more than 68t expendable.

200 t is even better. Or 500. Why not declare more?

Because 150 tonnes is the capability.

17 minutes ago, kerbiloid said:

As I have shown in the SpX thread, unlikely its reusable version capability is greater than 60 t, but this doesn't matter at this point, before they have flown  at least once.

You have shown nothing of the sort. 

15 minutes ago, kerbiloid said:

We should not forget Nexus and SeaDragon.

They have performed exactly same amount of flights as Starship did to the date, but are much more capable.

Ah, yes. Who can forget all the glorious static fires and flight tests of those behemoth engines?

[tater]

28 minutes ago, kerbiloid said:

We should not forget Nexus and SeaDragon.

They have performed exactly same amount of flights as Starship did to the date, but are much more capable.

Neither of which was actually built.

 

[tater]

This could at least be in the Artemis thread, since Starship is part of Artemis.

[Meecrob]

On 2/11/2022 at 12:27 AM, kerbiloid said:

Wut???

My point is that the fact of the matter is that if the US wants a solid propellant ICBM, they get it, regardless of what the civil space program is doing. If you haven't noticed, most civil rockets are adapted from military ones, not the other way around.

Edit: just to stop the pedants...yes, recently this is shifting, but when they were developing the SRBs for the space shuttle, they had thousands of solid-fueled missiles pointed at what the US called enemies in the cold war. They were NOT waiting for the STS program to develop solid fuel missiles....same boosters as are on SLS, to keep it on topic.

Edited February 14, 2022 by Meecrob

[tater]

The primary US ICBM has been a solid since 1962, various iterations of Minuteman, then the Peacekeeper for a couple decades in addition to that (also solid).

[SunlitZelkova]

Politics does play a part though. What kerbiloid is implying about Thiokol doesn't appear to be true, but is sort of in play with how North American Rockwell (located in California) got the contract to build the Space Shuttle (California was vital for Nixon's reelection bid).

So not "Thiokol needs money to build ICBMs so let's collude to let them build a spaceship to give them money" but instead "X company needs money so its employees will support my campaign so let's let them build a spaceship to give them money". Which could be considered "collusion" or nefarious in nature if you deliberately flout and misuse public interest and funds to achieve your goal.

[tater]

US projects like this always maximize the number of districts and have since President Washington commissioned the 6 frigates.

[kerbiloid]

On 2/13/2022 at 4:20 PM, tater said:

Neither of which was actually built.

N1 was. And  has flown four times. Just spent more money than Nexus and SeaDragon together, and gave the NK-33 engines for Antares.

Who knows, maybe the Raptors have same path.

[snip]

On 2/13/2022 at 4:37 PM, tater said:

This could at least be in the Artemis thread, since Starship is part of Artemis.

Maybe, but originally I just noticed that nobody will ruin the existing SRB technological chain, so the SLS usage is inevitable, and other rockets can be only an addition to it.

That's exactly this thread topic.

On 2/13/2022 at 8:03 PM, Meecrob said:

if the US wants a solid propellant ICBM, they get it, regardless of what the civil space program is doing.

The question is time, and no money can buy it.
If US starts needing an ICBM/SLBM mass production (for example, https://en.wikipedia.org/wiki/Prompt_Global_Strike), nobody will allow a pause.
It will stay a non-stop process, like it was since

On 2/13/2022 at 9:25 PM, tater said:

The primary US ICBM has been a solid since 1962, various iterations of Minuteman, then the Peacekeeper for a couple decades in addition to that (also solid).

(Which is also could be said about the 140 t capable Saturn V. Its production had started in early 1960s.
Then stopped, and now they are trying to build a 70+ t SLS and are happy when SpaceX talks about the 100+ t SH).

The SRB will be in production not because they are better, but because they let the show keep going unstppably.
The equipment should stay intact and serviced, the personnel should stay trained, the material support should be on rails.
So, they need a purpose.
Not so much purposes for a huge SRB except the heavy rockets.

The tactical ones are a bad example for the obvious reason. It's much easier to make a small SRB than a large one.

***

The space always was just an side applied purpose of military industry.
Nobody spends so much money just for peace.

If there were no ICBM, there would be no billion dollar satellites. Nobody would just even build them.

Think not just like space enthusiasts. They never played role in space history, and when they did, things got even worse.

On 2/13/2022 at 10:08 PM, tater said:

US projects like this always maximize the number of districts and have since President Washington commissioned the 6 frigates.

Unlike ICBM/SLBM, the six wooden frigates of President Washington were being built in hundred amounts everywhere and anyway were nothing compared to the British fleet.

The continental army was not dismissed.

Edited February 15, 2022 by Snark
Redacted by moderator

[kerbiloid]

9 hours ago, sevenperforce said:

SpaceX has stated that they no longer remove the engines from boosters between launches unless the telemetry and other data suggest a problem with one of the engines.

Their statements are nice, if they are truth.
Though this means that they have to dismiss the rocket due to a single part malfunction.

But no, the keyword is "unless the telemetry and other data suggest a problem"

And you can't know from their words, how often it happens. Every flight? Every ten flights?
I hardly can imagine how an engine can pass a defectoscopy check without the engine bunch disassembly.

How can you explain, why do they use twenty rockets at once, instead of spending them one by one?

My explanation is simple: most of the rockets are partially disassembled for servicing, and it takes months.

9 hours ago, sevenperforce said:

The "ten flight" target is not a pre-calculated flight number.

Any industrial product has a pre-calculated amount of rounds/cycles/whatever.

That's how they calculate the part thickness and select the materials

9 hours ago, sevenperforce said:

Why would you draw a comparison between the STS, with engines that couldn't even be relit without extensive servicing, to a rocket that can literally launch and land and static fire and relaunch?

Why do they not just wash and refuel Falcons and launch them next day?

9 hours ago, kerbiloid said:

The business is when a vehicle doesn't wait several months between flights.

So, twenty Falcons fly every week every rocket?

9 hours ago, sevenperforce said:

There is no business case for accelerating turnaround if your fleet is large enough that you don't need to accelerate turnaround.

There is no business case to build more rockets than you actually need for the moment. They take money even if just stay on ground.

9 hours ago, sevenperforce said:

Almost all known rocket designs are limited to a single flight. What are you talking about?

All designs which have been designed as reusables.

Engines, return vehicles, etc.

9 hours ago, sevenperforce said:

The engines on Falcon 9 fire up to five times per flight without any inspection at all and can be reflown with only minimal inspection and no significant servicing.

As well as the engines of Shuttle and Energy.

This just allows to pre-calculate the whole system lifespan.

And as SH has 33 engines, this is exactly what makes it even more depending on check and repair.

Remember, what are you telling about the ejection seats on cargo planes.

Here are 33 rocket engines instead.

9 hours ago, sevenperforce said:

Because 150 tonnes is the capability.

It's a powerpoint to the moment.

9 hours ago, sevenperforce said:

You have shown nothing of the sort. 

I did.

9 hours ago, sevenperforce said:

Who can forget all the glorious static fires and flight tests of those behemoth engines?

Does SH has more?

The Starship has not exploded just in one flight of (six?), and even with just the vernier engines.

9 hours ago, tater said:

Just a demo hopper surving 20% of flights with 3 engines of 33, and never getting close to 8 km/s.

Edited February 14, 2022 by kerbiloid

[tater]

25 minutes ago, kerbiloid said:

N1 was. And  has flown four times. Just spent more money than Nexus and SeaDragon together, and gave the NK-33 engines for Antares.

You said Nexus and Sea Dragon. Neither of which was built.

26 minutes ago, kerbiloid said:

Maybe, but originally I just noticed that nobody will ruin the existing SRB technological chain, so the SLS usage is inevitable, and other rockets can be only an addition to it.

SLS was designed to feed money into the existing Shuttle contractor districts.

This is the fundamental currency. Money to districts means jobs, etc, which makes the constituents feel like their rep is earning his keep, which keeps him in his job. That's how the sausage is made.

[tater]

28 minutes ago, kerbiloid said:

Unlike ICBM/SLBM, the six wooden frigates of President Washington were being built in hundred amounts everywhere and anyway were nothing compared to the British fleet.

They were the majority of the tiny US budget at the time.

[kerbiloid]

Just now, tater said:

They were the majority of the tiny US budget at the time.

And that's while they were cut. 

Unlike ICBM/SLBM they were not a force, but were requiring too much money.

Edited February 14, 2022 by kerbiloid

[tater]

FTS installing.

 

[sevenperforce]

13 hours ago, kerbiloid said:

23 hours ago, sevenperforce said:

SpaceX has stated that they no longer remove the engines from boosters between launches unless the telemetry and other data suggest a problem with one of the engines.

Their statements are nice, if they are truth.
Though this means that they have to dismiss the rocket due to a single part malfunction.

No, it means that if there is a part that isn't working, then they replace that one part.

Do you throw away your car if it needs a new tire?

If your car needs a new tire, do you have to take out the engine and all the seats to replace the tire?

13 hours ago, kerbiloid said:

But no, the keyword is "unless the telemetry and other data suggest a problem"

And you can't know from their words, how often it happens. Every flight? Every ten flights?
I hardly can imagine how an engine can pass a defectoscopy check without the engine bunch disassembly.

I know it might be hard to imagine, but there are these things called "x-rays" that allow you to see inside something without disassembling it. Particularly good when you don't want to disassemble things that are hard to put back together, like rockets and human joints.

There are also these things called "endoscopes" which allow you to put a very small camera inside of a very small hole and thus visually inspect the inside of something. Also very useful. 

13 hours ago, kerbiloid said:

How can you explain, why do they use twenty rockets at once, instead of spending them one by one?

My explanation is simple: most of the rockets are partially disassembled for servicing, and it takes months.

How can you explain why my local moving truck outlet has a dozen moving trucks in its parking lot? Why not just rent them out one at a time? Clearly, these moving trucks are all awaiting disassembly and servicing.

14 hours ago, kerbiloid said:

23 hours ago, sevenperforce said:

The engines on Falcon 9 fire up to five times per flight without any inspection at all and can be reflown with only minimal inspection and no significant servicing.

As well as the engines of Shuttle and Energy.

Ah, yes, the RS-25 engines. Famous for being able to air-start and fire up to five times per flight.

14 hours ago, kerbiloid said:

23 hours ago, sevenperforce said:

Because 150 tonnes is the capability.

It's a powerpoint to the moment.

The N1 was not a powerpoint.

Just because the N1 didn't actually make it to orbit doesn't mean it didn't have a notional payload to LEO of 95 tonnes.

SLS Block 1 is not a powerpoint. Block 1B is, but Block 1 is not.

14 hours ago, kerbiloid said:

23 hours ago, sevenperforce said:

You have shown nothing of the sort. 

I did.

No, you did not. Your math is full of conjecture, speculation, and made-up numbers.

14 hours ago, kerbiloid said:

23 hours ago, sevenperforce said:

Who can forget all the glorious static fires and flight tests of those behemoth engines?

Does SH has more?

The Starship has not exploded just in one flight of (six?), and even with just the vernier engines.

What do you think a vernier engine is, exactly?

And you'll also note that I said static fires and flight tests. Starship has dozens of successful static fires, eleven successful launches, and seven successful landings.

[tater]

The idea that the boosters waiting around to fly again are disassembled is pretty comical, there are loads of pictures inside SpaceX hangers where the booster being concentrated on (by the crew flying it, for example) is surrounded by other boosters.

[kerbiloid]

9 minutes ago, sevenperforce said:

What do you think a vernier engine is, exactly?

The tilted thing which exploded in Starships.

10 minutes ago, sevenperforce said:

No, it means that if there is a part that isn't working, then they replace that one part.

Do you throw away your car if it needs a new tire?

A part, whose characteristics are matching the requirements allowing it to survive till the next planned check, isn't replaced.

A part with characteristics outside of appropriate range, is sorted out and replaced.

13 minutes ago, sevenperforce said:

I know it might be hard to imagine, but there are these things called "x-rays" that allow you to see inside something without disassembling it.

First of all, these things are called "acoustic defectoscopy". The X-rays are usually applied later,

Secondly, I would like to watch how you are checking the engine assembly with X-rays without disassembling it. Not that much place to crawl into with the equipment.

Thirdly, most of defects are not defects of the seals where the X-rays can help.

Fourthly, it's a heap of metal, when X-ray can show you just a small part of the problems lying outside.

16 minutes ago, sevenperforce said:

There are also these things called "endoscopes" which allow you to put a very small camera inside of a very small hole and thus visually inspect the inside of something. Also very useful. 

I would like to watch how you are applying endoscopes to see invisible defects of the metal structure.

17 minutes ago, sevenperforce said:

How can you explain why my local moving truck outlet has a dozen moving trucks in its parking lot? Why not just rent them out one at a time? Clearly, these moving trucks are all awaiting disassembly and servicing.

If they don't use the trucks for moving cargo, the trucks are excessive. Or they just keep the obsolete trucks, but that's obviously not about Falcons.

19 minutes ago, sevenperforce said:

Ah, yes, the RS-25 engines. Famous for being able to air-start and fire up to five times per flight.

That doesn't matter. We don't know if Raptors have another pattern.

20 minutes ago, sevenperforce said:

The N1 was not a powerpoint.

Just because the N1 didn't actually make it to orbit doesn't mean it didn't have a notional payload to LEO of 95 tonnes.

N1 at least took off four times.

(Well, two...)

20 minutes ago, sevenperforce said:

No, you did not. Your math is full of conjecture, speculation, and made-up numbers.

All numbers and calculations which aI have provided, have been explained.

Nothing like that from the opponents.

5 minutes ago, tater said:

The idea that the boosters waiting around to fly again are disassembled is pretty comical, there are loads of pictures inside SpaceX hangers where the booster being concentrated on (by the crew flying it, for example) is surrounded by other boosters.

Why do they not use several boosters for their lifespan, building more instead?

Why pauses between the same instance flights?

Pictures are nice, but cost nothing.

They are not necessarily shot in actual worktime. Especially by such hype-oriented company like SpaceX.

Also how does a disassembled rocket look like? Heap of metal? Or just a rocket with one engine temporarily unmounted?

[tater]

16 hours ago, kerbiloid said:

Why do they not use several boosters for their lifespan, building more instead?

They have to continue to produce stage 2, and some customers demand new boosters. The employees required to manufacture those boosters either get paid to stand around not making boosters, or they can make boosters. That or SpaceX builds a bunch, fires everyone, then retrains and builds more later. Clearly they prefer to keep the production line warm.

The same applies to Merlins. Many parts are shared with M1D and Mvac, but they want to keep the production line functional at some level. They need only 1 Mvac per launch. Even operating at a skeleton crew on engines likely makes enough to build some new boosters, and replace some engines here and there.

All this nonsense doesn't matter, Falcon 9 is doing the bulk of getting stuff to space right now, and their prices are low.  [snip]

Edited February 15, 2022 by Snark
Redacted by moderator

[tater]

SpaceX has said there is minimal refurb on F9 boosters, and that they occasionally swap an engine. We sometimes see them (it's in the open) messing with the legs, as well, when they are taken off the ASDS.

Why would anyone care to not believe them? I could see if they were making some extraordinary claim, like "we have warp drive" you'd want proof, but a claim about maintenance is hardly an extraordinary claim. They say they do minimal F9 refurb, but it's still more than they want, hence SS/SH being designed for even less. Mundane claim is mundane. If ROSCOSMOS said that it took 10 man hours to wax a Soyuz booster so it looks pretty, I would simply believe them, because who cares. If some time after they started this new practice they reduced prices per kg because they claimed it reduced drag, should someone care as a customer if the wax job is really helping, or just pocket the cash saved?

Edited February 14, 2022 by tater

[SunlitZelkova]

[snip]

Starship has obviously been built, and has flown suborbital test flights, but many posts make it sound as though it is already flying payloads to orbit.

I'm not sure about this particular discussion, it is long and a little rant-ish so I don't want to waste time reading through the past two pages, but in general, his points are-

1. Starship has many unproven/untested aspects of its design and architecture, so it is incorrect to treat it as an already flying launch vehicle, as many actually do or indirectly imply. It could, regardless of how unlikely, could end up having a development schedule delayed as Angara for all we know. Most on this forum are optimists, perhaps kerbiloid could be described as a pessimist (realist?).

2. It is unknown what the internal state of SpaceX is, so it is incorrect to assume that it will have 100% support for the next two decades and fly when it does and with the claimed figures it will. A possibility, no matter how unlikely, does exist that there are errors in the design that are unknown and will cause delays with or significant redesign of the system. Again the whole optimist vs. pessimist thing comes into play here.

------

By the way, I personally feel this discussion is completely relevant to the SLS thread, insofar as posts bashing SLS in favor of SpaceX and Starship are allowed here. This portion of the discussion is basically just a very detailed rebuttal of the criticisms of the SLS design process, and therefore are on topic.

Edited February 15, 2022 by Snark
Redacted by moderator

[sevenperforce]

28 minutes ago, SunlitZelkova said:

Starship has many unproven/untested aspects of its design and architecture, so it is incorrect to treat it as an already flying launch vehicle, as many actually do or indirectly imply. It could, regardless of how unlikely, could end up having a development schedule delayed as Angara for all we know. Most on this forum are optimists, perhaps kerbiloid could be described as a pessimist (realist?).

I am all in support of realism.

What is not realistic (and is also rather annoying) is when individuals make emphatic, easily-rebuttable claims suggesting that they know a particular system will not work.

It would be like me saying that I know SLS will never actually launch, because it is supposed to send people to the moon and no crewed moon rocket used solid rocket boosters, but SLS has solid rocket boosters. And then adding that the only solid rocket boosters of this size were recoverable, but the SLS rocket boosters are not recoverable, and therefore they will not burn properly. And then adding that because SLS Block 1 cannot send a useful crewed payload to NRHO, SLS Block 1B won’t be able to, either. (Note, that last criticism is different from claiming that the EUS is vaporware, which it is. I can criticize EUS for being vaporware without claiming that EUS cannot do the thing it is being designed to do. Clearly it is possible to design EUS to do the thing EUS is designed to do.)

There are many legitimate criticisms of the yet-unretired risks associated with SLS, just like there are many legitimate criticisms of the yet-unretired risks associated with Starship+SuperHeavy. But claiming that these risks/issues are per se unsolvable (particularly by allusion or analogy to utterly unrelated issues or grassgrab math) is silly.

[kerbiloid]

15 hours ago, tater said:

and some customers demand new boosters.

Why, when a used Falcon is as reliable as a new one?

15 hours ago, tater said:

They have to continue to produce stage 2

The talk is about the reusable stage 1.

The expendable stage 2 just spends a reusable engine as expendable every flight.

15 hours ago, tater said:

The employees required to manufacture those boosters either get paid to stand around not making boosters, or they can make boosters.

Brilliant words.
The SRB  production needs the same, and is more important than Martian colonies.

15 hours ago, tater said:

SpaceX has said

about Red Dragon, Colonial Transporter, ISRU methane, one-way Martian trip, and a megaton of other hype nonsense.

Currently they have a half-Proton rocket with reusable first stage of unclear efficiency of reusability and a single-use crewed spaceship which can be used several times more as a cargo box.

15 hours ago, tater said:

We sometimes see them (it's in the open) messing with the legs, as well, when they are taken off the ASDS.

We don't see them messing with other parts, because they let us see them messing with legs.

15 hours ago, tater said:

They say they do minimal F9 refurb

"We repaired the rocket engine just a little, don't bother with it."

Do they crawl inside with a wrench and a n Xray-scope?

Or the unmount the engines one by one, like it would be normally done?

For example the airplane engines hang down from the wings and are available for servicing from 360° without unmounting.
(Well, on B-52 probably from 240°, as they are paired).

[snip]

Russia has performed several times more launches and cargo traffic on other rockets than Soyuz, if you aren't aware of.

Soyuz is a "it works, don't repair".

Both Angara's URM-1 and URM-2 work, but until ISS has gone and a new orbital station or lunar missions get required, it has not so many objectives to launch it more often.

Engines are from 80s, not from 50s, and it's funny that American buy them for kerolox rockets, after having built Saturn.

Though, I can't see how can the Russian rockets relate to the topic of which boosters prefer in US.

[snip]

Edited February 15, 2022 by Snark
Redacted by moderator