SpaceX (Vol. 2)
Discussion
The velocities etc would obviously make it significantly more complex than what's I'm about to suggest, but the payload capability of super heavy/ starship surely gives significant flexibility by itself. If they're still struggling with starship re-entry they could "just" pack a dragon capsule into the ship with a beefier heat shield (I know it sounds stupid!)
The potential projects that could be put together if it was decided to use expendable starships could be very interesting...
The potential projects that could be put together if it was decided to use expendable starships could be very interesting...
I believe the Dragon capsule has a heatshield that can cope with reentry from a lunar mission. The dearMoon private moon flyby mission planned to use Dragon originally. https://en.wikipedia.org/wiki/DearMoon_project
Are we there yet...I mean hundreds and hundreds of posts and still we are not there......Makes NASA and Apollo look an absolute brilliant achievement. They not only had to design and invent new technologies but the Math that went along with with it. They also had to invent the computers as they went along. This bunch have the technology the Math and previous experience so I will ask again are we there yet 
Toaster said:
Are we there yet...I mean hundreds and hundreds of posts and still we are not there......Makes NASA and Apollo look an absolute brilliant achievement. They not only had to design and invent new technologies but the Math that went along with with it. They also had to invent the computers as they went along. This bunch have the technology the Math and previous experience so I will ask again are we there yet
In 1966, NASA spent 4.4% of the US federal budget in just that one year.It's about $55bn in 2023 dollars.For the Apollo program it was around $350bn in 2023 dollar terms.
SpaceX has so far spent about $5bn on the whole starship program including starbase, over the last 12 years.
SpaceX may be able to go faster if they are granted 10x the budget but on what they have been spending so far they are doing great.
Timothy Bucktu said:
Not for the fanboys, but interesting take if you have an open mind...
https://youtu.be/nxG0WAwwrGk?si=5XSKp3KZNQdGZdCR
https://youtu.be/nxG0WAwwrGk?si=5XSKp3KZNQdGZdCR
- triggered
He also doesn't appear to realise that just because a start-up is bulls
ting or giving an incomplete picture doesn't mean that they aren't aware of all the "issues" that you've discovered in your casual glance at their technology and might have a plan to do something about it. In fact doing the most basis risk analysis is base level engineering technologist level.The fact that he occasionally targets actual bulls
t products doesn't mean he's worth listening to. My general advice is not to both watching any of his content if you want insightful coverage there are much better options with a much better ratio of signal to noise.
Edited by Talksteer on Wednesday 24th April 10:47
Talksteer said:
Timothy Bucktu said:
Not for the fanboys, but interesting take if you have an open mind...
https://youtu.be/nxG0WAwwrGk?si=5XSKp3KZNQdGZdCR
https://youtu.be/nxG0WAwwrGk?si=5XSKp3KZNQdGZdCR
- triggered
He also doesn't appear to realise that just because a start-up is bulls
ting or giving an incomplete picture doesn't mean that they might be aware of all the "issues" that you've discovered in your casual guidance at their technology and might have a plan to do something about it.The fact that he occasionally targets actual bulls
t products doesn't mean he's worth listening to. My general advice is not to both watching any of his content if you want insightful coverage there are much better options with a much better ratio of signal to noise.
- Hyperloop....?
Yep, he was totally wrong calling that one out.
Eric Mc said:
Back in World War 2, when the Air Ministry were giving consent to Glosters to produce Britain's first jet fighter, the Meteor (and by definition, the first practical as opposed to experimental, jet aircraft) they told Gloster SPECIFICALLYnot to mess about with any advanced aerodynamics. The brief was that this new aircraft was making use of new technology and new concepts regarding the power plants and therefore they should not mess about with any other untried or untested aspects of the design . That could (and did - of course) come later.
I look on what is happenng with spaceflight right now in a similar light. We trying to move from a largely "rare" and to some extent experimental mode of operation to a more routine mode. This has been a goal in spaceflight for a long time. It was the ethos behind the Space Shuttle - but that diodn't work out because the craft did not embrace the British Air Ministry approach of not being too experimental if you are trying for routineness.
SpaceX seem to be getting there with their Falcon series of rockets which are becoming almost dull in their routine and dependable launches.
Starship is very much more experimental in its approach - new technology engines being used in an untried rocket and spacecraft mixed with untried re-entry and landing techniques that need to work on three different worlds which require very different approaches.
It all seems very demanding. I'm not saying none of this can be done. But I think that it will take a bit longer than maybe NASA are prepared to wait.
The the Meteor was rapidly relegated to secondary duties precisely because it didn't do anything advanced with it aerodynamics and was thus obsoleted by F86 and Mig15 which did. I look on what is happenng with spaceflight right now in a similar light. We trying to move from a largely "rare" and to some extent experimental mode of operation to a more routine mode. This has been a goal in spaceflight for a long time. It was the ethos behind the Space Shuttle - but that diodn't work out because the craft did not embrace the British Air Ministry approach of not being too experimental if you are trying for routineness.
SpaceX seem to be getting there with their Falcon series of rockets which are becoming almost dull in their routine and dependable launches.
Starship is very much more experimental in its approach - new technology engines being used in an untried rocket and spacecraft mixed with untried re-entry and landing techniques that need to work on three different worlds which require very different approaches.
It all seems very demanding. I'm not saying none of this can be done. But I think that it will take a bit longer than maybe NASA are prepared to wait.
Starship is by any reasonable standard moving at quite a pace and has many more applications than just sending men to the moon. The idea of blowing money on incredibly expensive single purpose kit when a massively greater capability is being developed to fulfill a commercial goal at a fraction of price is crazy.
It's a bit like doggardly developing a bespoke large aircraft to act as an AWACS rather than using a commercial airliner.
The Meteor did what was asked of it and was a useful aeroplane right into the 1960s. OK, it didn't last too long as a front line fighter due to the rapid development of jets within their first ten years but it was able to perform other roles quite well for a long time.
The 262, whilst theorethically a more advanced and better performing plane, had a much shorter operational life . And that wasn't just because Germany lost the war. Both the French and the Czechs looked very carefully at continuing production post war. The Czechs even developed their own version, the Avia S-92. However, the same reliability issues that dogged the German 262s also hampered the S-92 and, like the Meteor, the 262 became obsolete as a fighter very quickly. So the Czechs ended up replacing them very quickly by early Soviet designs.
Even though the Saturn V was designed primarilly to get men on the moon, it had a lot of potential and could have been used for lots of other heavy lift tasks - as demonstrated by the Skylab mission. However, short sighted politicians ensured that only a small number of Saturn Vs were ever built. If they had been a bit more clever, developed versions of the Saturn V might still be in use today. Look how long the Delta and Atlas series lasted.
The 262, whilst theorethically a more advanced and better performing plane, had a much shorter operational life . And that wasn't just because Germany lost the war. Both the French and the Czechs looked very carefully at continuing production post war. The Czechs even developed their own version, the Avia S-92. However, the same reliability issues that dogged the German 262s also hampered the S-92 and, like the Meteor, the 262 became obsolete as a fighter very quickly. So the Czechs ended up replacing them very quickly by early Soviet designs.
Even though the Saturn V was designed primarilly to get men on the moon, it had a lot of potential and could have been used for lots of other heavy lift tasks - as demonstrated by the Skylab mission. However, short sighted politicians ensured that only a small number of Saturn Vs were ever built. If they had been a bit more clever, developed versions of the Saturn V might still be in use today. Look how long the Delta and Atlas series lasted.
Eric Mc said:
Even though the Saturn V was designed primarilly to get men on the moon, it had a lot of potential and could have been used for lots of other heavy lift tasks - as demonstrated by the Skylab mission. However, short sighted politicians ensured that only a small number of Saturn Vs were ever built. If they had been a bit more clever, developed versions of the Saturn V might still be in use today. Look how long the Delta and Atlas series lasted.
In the process of developing SLS a couple of ideas were looked at, and the Kerolox designs ended up using gas generator engines with thrust on the region of 2 million lbf... updated F1s. In fact the design ended up with a very similar height and diameter to a Saturn V.NASA slideshow
Indeed.
Sadly, it was decided that after such a long time, too many aspects of the Saturn V were no longer feasible. For instance, some of the metals used and assembly techniques were no longer available and, probably more importantly, too many of the individuals involved in developing the original Saturns were long gone.
Bsically, it was too late to resurrect the Saturn - even in a more modern form.
Sadly, it was decided that after such a long time, too many aspects of the Saturn V were no longer feasible. For instance, some of the metals used and assembly techniques were no longer available and, probably more importantly, too many of the individuals involved in developing the original Saturns were long gone.
Bsically, it was too late to resurrect the Saturn - even in a more modern form.
Eric Mc said:
The Meteor did what was asked of it and was a useful aeroplane right into the 1960s. OK, it didn't last too long as a front line fighter due to the rapid development of jets within their first ten years but it was able to perform other roles quite well for a long time.
The 262, whilst theorethically a more advanced and better performing plane, had a much shorter operational life . And that wasn't just because Germany lost the war. Both the French and the Czechs looked very carefully at continuing production post war. The Czechs even developed their own version, the Avia S-92. However, the same reliability issues that dogged the German 262s also hampered the S-92 and, like the Meteor, the 262 became obsolete as a fighter very quickly. So the Czechs ended up replacing them very quickly by early Soviet designs.
Even though the Saturn V was designed primarilly to get men on the moon, it had a lot of potential and could have been used for lots of other heavy lift tasks - as demonstrated by the Skylab mission. However, short sighted politicians ensured that only a small number of Saturn Vs were ever built. If they had been a bit more clever, developed versions of the Saturn V might still be in use today. Look how long the Delta and Atlas series lasted.
In the 1950s/60s NASA and the DOD also had the Nova rocket series at the concept/design stages. These days they are generally looked at as the "post-apollo" rockets, but in general they were developed in tandem (in fact, some Novas came first) -- and they had a lot of parts compatibility.The 262, whilst theorethically a more advanced and better performing plane, had a much shorter operational life . And that wasn't just because Germany lost the war. Both the French and the Czechs looked very carefully at continuing production post war. The Czechs even developed their own version, the Avia S-92. However, the same reliability issues that dogged the German 262s also hampered the S-92 and, like the Meteor, the 262 became obsolete as a fighter very quickly. So the Czechs ended up replacing them very quickly by early Soviet designs.
Even though the Saturn V was designed primarilly to get men on the moon, it had a lot of potential and could have been used for lots of other heavy lift tasks - as demonstrated by the Skylab mission. However, short sighted politicians ensured that only a small number of Saturn Vs were ever built. If they had been a bit more clever, developed versions of the Saturn V might still be in use today. Look how long the Delta and Atlas series lasted.
The Nova C8 design (which is similar to the also unbuilt Saturn-C8) uses 8x F1 engines as opposed to the 5x F1s used on the Saturn V, and it has a 49' (12.2m) first stage diameter -- this last note is surprisingly a large part of why it was not selected / was cancelled. Federal subsidies (the pork-barrel) need to go to where politics says they need to go and the factory mooted for the build simply wasn't big enough to cope with it & the diameter would have been difficult to transport to launch sites. The Saturn C8 was the direct ascent mode of moonshot. The Saturn-V fit in that factory, and was designed to be airlifted for transport.
The C8 designs are similar sized (initial mass) to the Starship v1 prototypes SpaceX have been testing to date; they are around 10 million lbs (5000t) takeoff weight. Of course there are a huge number of differences, the main thing being that the F5 is a keralox engine and starship's raptors are methalox. (note: Starship tests so far have most likely not carried anything like max design specification of weight, and the motors on IFT1/2/3 have most likely been running well under their design limit as a result).
In terms of Starship development;
The last 4 starship v1 ships (#29,30,31,32; have been built already (having been started July 22-Feb23). They are all pure test vehicles and are just for research since new builds will move to the v2 design from now on.
Ship 29 and Booster 11 are the constituent parts for integrated flight test 4 (IFT4), which is expected to happen in May.
Ships 33,34,35 were all started in late 2023 but then scrapped soon after (only #35 was seen, and it was literally just a nosecone). Only SpaceX will know what they were supposed to become (more v1, ground-test, v2 but aborted for a better v2?)
Starship v2 is a little larger than v1 and looks a little different due to flap locations and the interstage area design.
The first two of the v2 are ships 36 and 37 and both are in build as of January 2024.
Starship v3 is considerably larger than any of this stuff, in combination with the larger booster, it's closer to 8000t takeoff weight than 5000t, with a large proportion of the increase going to the second stage (v3 ship) which will have 9 raptors rather than the current 6.
Nothing from v3 has been spotted in build yet, but it's expected to be so much larger that some of the ground equipment will have to grow to cope (eg. launch tower).
edited for speeling
Edited by CraigyMc on Wednesday 24th April 12:35
ridds said:
Talksteer said:
Timothy Bucktu said:
Not for the fanboys, but interesting take if you have an open mind...
https://youtu.be/nxG0WAwwrGk?si=5XSKp3KZNQdGZdCR
https://youtu.be/nxG0WAwwrGk?si=5XSKp3KZNQdGZdCR
- triggered
He also doesn't appear to realise that just because a start-up is bulls
ting or giving an incomplete picture doesn't mean that they might be aware of all the "issues" that you've discovered in your casual guidance at their technology and might have a plan to do something about it.The fact that he occasionally targets actual bulls
t products doesn't mean he's worth listening to. My general advice is not to both watching any of his content if you want insightful coverage there are much better options with a much better ratio of signal to noise.
- Hyperloop....? Yep, he was totally wrong calling that one out.
He does a whole load of "experiments" with vacuums which show he has no idea of scaling, he claims if the tube is breached you'll have a shock wave progressing down the tube for hundreds of miles causing devastation. In fact what you get is pressure loses (due to air flowing rapidly inside the tube) in the tube resulting in that sonic shockwave rapidly diminishing in pressure. This would mean that an oncoming pod would meet a much lower pressure shockwave followed by a gradual ramp up in air pressure. Provided the pod is aerodynamic the net result of encountering the oncoming air is likely to be more like being in a plane at 600mph and then switching off the engine than crashing into a brick wall.
He's also obsessed with the "mighty power of the vacuum" as if engineers aren't capable of designing pressure vessels that can resist negative 1 bar. You just over design it so that it won't fail if part of the tube gets ovalised. We routinely design large pipes with anything up to 1000 bar of pressure resistance, a vaccum is relatively trivial. Hyperloop 1's test tube was designed to ASME standards and was about 15mm thick.
His claims around thermal expansion just basically show that he doesn't know anything about it, from a mass per length basis a hyperloop tube uses about as much steel as there is in 6 railway lines. Ergo you could just tension the tube (or heat it to max operating temp) before you weld it and fix on new sections. This is what they do with rail tracks. He literally talks about differential heating (top in the sun bottom in shadow) causing a hyperloop tube to bend and buckle while stood next to a rough ass prototype tube which isn't doing either of those things because 1: differential heating of conductive steel is difficult and 2: the stresses imposed are less than those imposed by the tubes own weight so it goes nowhere. Personally I'd just fit the tubes loose like a water pipe and then use a welded bellows seal between each section would take about 5 minutes to fit.
For all the invective around Hyperloop it's notable that Elon Musk didn't start developing it he just threw the idea out to try and get people to work on it. He was perfectly up front that the end product wouldn't look anything like what was initially proposed.
The Hyperloop 1 demonstrator and the student competitions made meaningful progress in inductrack maglev designs and there are now new companies working to make that system backwards compatible with conventional rail. Those demonstrations also showed that the vehicle itself was eminently feasible. The issue was that the requirements for straightness of the track plus the plus the potential for naughty people to attack it means that its probably best to stick the thing under ground (unless you have a massive empty desert like the likely first customers will have). Hence the place Musk put his own money was into tunnelling.
Just because the early crazy money has run out doesn't mean that nobody is working on this or that it won't happen. You still get lots of rail fans making straw man arguments that the system won't work because the pods are small (chain them together if you must) or because trains must not travel within the stopping distance of another train so must Hyperloop pods and therefore the capacity of the system would be small. In practice I suspect the system would have a safety case more like a roller coaster than a railway line.
The physics are fine and most of the complaints are like someone stating that commercial jetliners aren't possible in 1945 because current planes are dangerous, noisey and slow.
Edited by Talksteer on Wednesday 24th April 12:30
Beati Dogu said:
They’ve done 301 Falcon 9 / Falcon Heavy landings now.
it’s so routine now it is taken for granted.
They are going to try a virtual Starship booster landing on the next flight. I.e. a controlled descent into the sea next to an imaginary tower.
It's a silly comparison of course, but they have been more reliable than the train I use to get to the city, for several years.it’s so routine now it is taken for granted.
They are going to try a virtual Starship booster landing on the next flight. I.e. a controlled descent into the sea next to an imaginary tower.
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