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Merged SpaceX’s Starship Rocket Explodes After Launch/Starship hop

Then why does the booster not need protection for the engines?
In terms of aerodynamic heating, probably because they're already designed to get hot without falling apart. In terms of aerodynamic loading, probably because the shock wave front forms in front of them.

ETA: While orbital entry trajectories are shallower, they impose an overall greater heat loadi on the entering vehicle. We need to be clear what we mean by "stresses."
 
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you seem confused about my point.
This was the 7th test flight of Starship, never managing to reach orbit, and New Glenn did it first try.
Objectively, the New Glenn MAIDEN flight was a bigger success and achievement than the Starship test - but commentators are bending over backwards to make them sound equivalent.
Starship doesn't need reaching orbit for testing reentry. The speed is just shy of orbital speed, basically it means it just doesn't have to do de-orbit burn. It's obvious they could do orbit, doing that would achieve nothing. It could only demonstrate they can. But they are undisputed kings of bringing stuff to orbit and further. New Glenn chose to demonstrate they can do it, to join the club, and good for them. But it's just a gesture.
 
Then why does the booster not need protection for the engines?

In terms of aerodynamic heating, probably because they're already designed to get hot without falling apart. In terms of aerodynamic loading, probably because the shock wave front forms in front of them.

ETA: While orbital entry trajectories are shallower, they impose an overall greater heat loadi on the entering vehicle. We need to be clear what we mean by "stresses."
Also, as regards to Falcon 9, it does get some protection for the engines by having an entry burn to slow it down during the critical heating phase of re-entry which typically drops the booster entry velocity from around 6500 kph to 3,000 kph for ASDS (slower for RTLS).

As regards Super Heavy, it doesn't have an entry burn, and the engine bells don't need much protection as they are already designed to withstand that level of heating. It is the mechanisms and the rocket engine components above those bells that is at risk.
Raptor-Thermal-Protection.jpg

The 13 gimballing centre engines have a conical section around the top of the bell to protect the engine components above the bell.

Raptor-Flat-Plate-Protection.jpg

The outer 20 fixed engines have a flat plate for shielding.

There was also talk of running cryogenic propellant through the 13 centre engines to help with cooling, but I'm not sure whether that has been implemented.
 
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Booster has a lot lower velocity. New Glenn separates at 4000ish MPH, Heavy Booster at 4000ish KMH. Re-entry from orbit is almost on orbital velocity, 27000ish KMH (16700MPH).
Which of the point I am making. I am not an expert on rocketry but there are clearly differences between the stresses on the boosters compared to the orbital components. It's that which SpaceX is yet to demonstrate it can do better than the Shuttle.
 
Which of the point I am making. I am not an expert on rocketry but there are clearly differences between the stresses on the boosters compared to the orbital components. It's that which SpaceX is yet to demonstrate it can do better than the Shuttle.
Well of course, but you are comparing things which are simply not comparable.

The Space Shuttle was a fully operational space launch system that flew 135 missions over a period of 30 years. As we all know, two of these missions failed catastrophically and killed two crews of seven. Development began in 1968, with the program being launched in 1972. The first flight was 1981.

Starship is still undergoing test flights (a concept that you and several others here still do not seem to understand). It was formally announced (as BFR) in late 2017. At roughly the same stage that SpaceX are at now with Starship, NASA (1977) had only just completed glide tests on Enterprise!
 
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the bottom line seems clear to me: Starship will end up being far heavier to fix the issues, decreasing the advertised payload capacity.
Umm, nope.

The advertised payload capacity is based on using Raptor 2 engines in the booster stage

Raptor 2
TW ratio 141:1
Thrust 230,000 kgf

Raptor 3
TW ratio 184:1
Thrust 280,000 kgf

Raptor 3 has been test fired, but hasn't flown yet. A 30%+ increase in both the thrust to weight ratio and the raw thrust of the 33 Raptor engines should easily compensate for any additional dry weight of the stack.

In addition to all that, Raptor 4 is under development. Its expected to be around 15% lighter, and have 15% more thrust... so
TW Ratio 246:1
Thrust 323,000 kgf
 
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I was referring to a reusable re-entry capable vehicle that can carry humans. If you had just checked, in good faith, I am happy to clarify any ambiguity.

Looks like a goalpost move to me. At least have the courage to own your own words. If you meant "a reusable re-entry capable vehicle that can carry humans" you should have said Starship, not SpaceX.

But for the record anyway, SpaceX have already developed and are flying "a reusable re-entry capable vehicle that can carry humans"... its called Crew Dragon. So far, its made 15 crewed launches

10 for NASA
Crew Demo (Endeavour) May 30, 2020
Crew 2 (Resilience) November 16, 2020
Crew 2 (Endeavour) April 23, 2021
Crew 3 (Endurance) November 11, 2021
Crew 4 (Freedom) April 27, 2022
Crew 5 (Endurance) October 5, 2022
Crew 6 (Endeavour) March 2, 2023
Crew 7 (Endurance) August 6, 2024
Crew 8 (Endeavour) March 4, 2024 (currently at ISS)
Crew 9 (Freedom) September, 2020 (currently at ISS preparing to rescue two NASA astronauts stranded by Boeing's incompetence)

5 For Commercial clients
Inspiration 4 (Resilience) September 16, 2021 (raised over US$250 million for St. Jude Children's Research Hospital)
Axiom 1 (Endeavour) April 8, 2022
Axiom 2 (Freedom) May 21, 2023
Axiom 3 (Freedom) January 18, 2024
Polaris Dawn (Resilience) September 10, 2024

- That's 15 manned missions in their first four years... one more than Space Shuttle :newlol
 
Looks like a goalpost move to me. At least have the courage to own your own words. If you meant "a reusable re-entry capable vehicle that can carry humans" you should have said Starship, not SpaceX.

But for the record anyway, SpaceX have already developed and are flying "a reusable re-entry capable vehicle that can carry humans"... its called Crew Dragon. So far, its made 15 crewed launches

10 for NASA
Crew Demo (Endeavour) May 30, 2020
Crew 2 (Resilience) November 16, 2020
Crew 2 (Endeavour) April 23, 2021
Crew 3 (Endurance) November 11, 2021
Crew 4 (Freedom) April 27, 2022
Crew 5 (Endurance) October 5, 2022
Crew 6 (Endeavour) March 2, 2023
Crew 7 (Endurance) August 6, 2024
Crew 8 (Endeavour) March 4, 2024 (currently at ISS)
Crew 9 (Freedom) September, 2020 (currently at ISS preparing to rescue two NASA astronauts stranded by Boeing's incompetence)

5 For Commercial clients
Inspiration 4 (Resilience) September 16, 2021 (raised over US$250 million for St. Jude Children's Research Hospital)
Axiom 1 (Endeavour) April 8, 2022
Axiom 2 (Freedom) May 21, 2023
Axiom 3 (Freedom) January 18, 2024
Polaris Dawn (Resilience) September 10, 2024

- That's 15 manned missions in their first four years... one more than Space Shuttle :newlol
Ah, so SpaceX and the Space Shuttle are in fact comparable. ;)
 
Ah, so SpaceX and the Space Shuttle are in fact comparable. ;)
Any two things are comparable. What this comparison tells us is that the shuttle had significant advantages, but still underperformed relative to SpaceX.

Again, there's plenty of legitimate reasons to hate Elon Musk. None of them justify hatred-fueled canards about SpaceX.
 
Any two things are comparable. What this comparison tells us is that the shuttle had significant advantages, but still underperformed relative to SpaceX.

Again, there's plenty of legitimate reasons to hate Elon Musk. None of them justify hatred-fueled canards about SpaceX.
Calm down young fella. It was a light hearted aside to a comment. Where did "hate" come from?
 
Calm down young fella. It was a light hearted aside to a comment. Where did "hate" come from?
Yes, I would very much like to know where all this unskeptical hate is coming from. Not in the abstract sense that JayUtah seems to intend, but in the applied practical sense that drives most of the absurd arguments against SpaceX.
 
Yes, I would very much like to know where all this unskeptical hate is coming from. Not in the abstract sense that JayUtah seems to intend, but in the applied practical sense that drives most of the absurd arguments against SpaceX.
I have nowhere expressed any hate toward Space, or Musk. I don't care about them enough to hate, or like, them. Their failures or successes will have zero impact on what remains of my life. Although on a purely academic level I think that advances in space exploration, by anyone, are a positive thing. Nor do I particularly care about other posters' emotions re SpaceX, or Musk. Yet you used the word "hate" in direct response to my post that you quoted. Why? If you want discuss hatred toward SpaceX or Musk take it up with those who have expressed such and leave me out of it.
 
Yes, I would very much like to know where all this unskeptical hate is coming from. Not in the abstract sense that JayUtah seems to intend, but in the applied practical sense that drives most of the absurd arguments against SpaceX.
Falcon 9 is a spectacular success. That doesn't mean Starship will be. The problems that NASA found no easy fixes for may also mean Starship cannot achieve Musk's more extreme ambitions. Rapid reuse of the descent vehicles may be impossible. Dragon is slow reuse, not rapid, so the problems weren't solved there.
NASA had hoped for rapid reuse of a vehicle as safe as a passenger jet. That never happened. It was slow to reuse and was never safe enough for everyday civilian use. Passengers had to expect they might not be coming back, just like with the other legacy rocket systems.
 
Any two things are comparable. What this comparison tells us is that the shuttle had significant advantages, but still underperformed relative to SpaceX.

Again, there's plenty of legitimate reasons to hate Elon Musk. None of them justify hatred-fueled canards about SpaceX.
I think it's more the vision for SpaceX that Musk has created. One where he regularly promises the impossible.
 
Falcon 9 is a spectacular success. That doesn't mean Starship will be. The problems that NASA found no easy fixes for may also mean Starship cannot achieve Musk's more extreme ambitions. Rapid reuse of the descent vehicles may be impossible. Dragon is slow reuse, not rapid, so the problems weren't solved there.
NASA had hoped for rapid reuse of a vehicle as safe as a passenger jet. That never happened. It was slow to reuse and was never safe enough for everyday civilian use. Passengers had to expect they might not be coming back, just like with the other legacy rocket systems.
Space Shuttle was 1970s technology. There was a lot they could not do which we can do now as materials sciences have advanced. Here's just one example - Resusable heat shields

The Space Shuttle required every one of the 24,300 tiles to be inspected, and if defective, replaced. They were made from porous silicon material called LI-900, which is made from pure silica glass fibres. At least half the time it took to refurbish the Orbiter was spent on this task. Each tile had to be inspected for damage and waterproofed. Initially they used hexamethyldisilazane (a compound not unlike Scotchguard) for waterproofing but it was found to not be very effective, as well as having a tendency to soften the RTV adhesive attaching the tiles to the hull. They ended up having to inject each tile with dimethylethoxysilane. They also injected tetraethyl orthosilicate to make make them more dense. Very few of the HRSI tiles (the black ones that bore the brunt of re-entry heating) survived more than three flights without some material damage, and therefore needed to be replaced. Much of the tile damage was caused by hitting ice in the upper atmosphere during ascent and from micrometeoroid and space debris impact while docked.

SpaceX has designed the Crew Dragon to allow for inspections and refurbishment of the heat shield between missions, but each individual shield is generally only used for a limited number of flights before it needs to be replaced. The heat shield is designed for reusability, but it is not reused in the same way as other components like the Falcon 9 first stage. It is made from a material called PICA-X (Phenolic Impregnated Carbon Ablator). While the heat shield can survive multiple missions, it typically shows signs of wear after each flight due to the ablation process that occurs during re-entry. Essentially, it is a compromise that results in far less inspection and maintenance being needed. The biggest simple impactor of maintenance times is the amount of time the capsule spends in space. While the private missions are just a few days, missions to the ISS require the capsule to remain docked to ISS for months at a time, typically around 200 days (time on station for Shuttle Orbiters averaged 12 days). I haven't done the math for all of the Crew Dragon capsules but it wouldn't surprise me if they have already done more time in space than the orbiters did over the entire Shuttle programme. For example, Endeavour has spent 731 days in space... the equivalent of 61 shuttle missions.... none of the Shuttle Orbiters flew anywhere near close to that number - the record holder is Discovery with 39 missions.
 
i agree, funding r&d for companies that are perfectly capable of turning enormous profits as it is seems like a foolish use of taxpayer money. again i don't know that scam is the correct term to describe this, probably not. but the sentiment is similar.
I don't think any of Musk's companies are even remotely capable of turning a profit without massive gobs of welfare.
 
Starship doesn't need reaching orbit for testing reentry. The speed is just shy of orbital speed, basically it means it just doesn't have to do de-orbit burn. It's obvious they could do orbit, doing that would achieve nothing. It could only demonstrate they can. But they are undisputed kings of bringing stuff to orbit and further. New Glenn chose to demonstrate they can do it, to join the club, and good for them. But it's just a gesture.
Funny how you can dismiss a company tha have demonstrated that they can do the job on their first flight, but are mad to defend a company who aren't even close after seven.

Blue Origin's current failure rate is 0%, SpaceX's is 100%. And that's on the firzt stage criteria for the job at hand. If the decision hadn't been made by a corrupt official in Musk's back pocket, SpaceX would have gotten their contract termination letter this week.
 
the one question no one dares to ask is: do we really need that much payload capacity for LEO or Orbit?
SpaceX only works (barely) because it moves Starlink satellites, and they are unlikely to be profitable anytime soon or for long: Europe is about to built its own fleet of LEO communication satellites, quantum capable, because they, just like everyone else in the world, doesn't relish the idea of having to depend for their critical communication of a hack like Musk.
There is no business model for Bezos's Space Factories, never mind the infinite money sink that a Mars colony would be.
 
Funny how you can dismiss a company tha have demonstrated that they can do the job on their first flight, but are mad to defend a company who aren't even close after seven.

Blue Origin's current failure rate is 0%, SpaceX's is 100%. And that's on the firzt stage criteria for the job at hand.
Go back to school and take remedial mathematics class, because you really suck at mathematics.

Based on your "first stage criteria for the job at hand"

- Blue Origin failed to return and land their booster from their first attempt THAT is 0% success rate
- SpaceX landed and caught their booster on the first and third of three attempts... that is 66.6% success rate

So, you lied!

If the decision hadn't been made by a corrupt official in Musk's back pocket, SpaceX would have gotten their contract termination letter this week.
And your evidence for this is?


Never mind...Haters don't need evidence to fuel their blind, spittle-filled rage! They just make stuff up from whole cloth, like you just did.
 
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At least three billion, though I think there was extra money bunged at them mid way through.
Wrong. They are not being paid anything for test flights. They are being paid to develop a Lunar HLS.

If you keep making stuff up and/or keep pulling crap out of your arse, you're going to keep making a fool of yourself like you did with that answer.
 
plenty to hate

luckily, the billionaires have such staunch defenders.
They don't need defenders because the haters attacking them don't know what they are talking about and have no facts in their armoury. They are bringing their hateful feelings and clueless opinions to a fact fight.... and as we know, facts don't care about feelings... or opinions
 
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But why?
It's not like Musk is providing a public service or using his own money to play astronaut: he is using taxpayer and investor money to corner a market for profit, one that will end up benefitting few people aside from himself.

We won't see any of the money he ought to be paying in taxes, but we DO have the right to give him ◊◊◊◊ 24/7 (for how much longer is the question).
So I don't see why we get ◊◊◊◊ from you for pointing out that he has way overpromised what SpaceX would do, and keeps failing at it: as you pointed our, he is paid to develop a Lunar lander, not to make reusable rockets - that's his thing to make more money for him. So by that metritm the last test was a failure for taxpayers, a win for him, personally.

Either SpaceX can show the results it promised, or it can't - we don't have to accept explanations or excuses when it's our taxes paying for it.
 
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WASHINGTON, May 15 (Reuters) - Elon Musk's SpaceX has tapped NASA's former human spaceflight boss Kathy Lueders to help oversee development of the company's moon and Mars rocket called Starship, a person familiar with the hire said on Monday.
Lueders, the second former NASA human spaceflight chief to retire and move to SpaceX in recent years, represents another key hire for the company as it races to develop and use Starship for landing NASA astronauts on the moon within the next decade.
Lueders spent 31 years at NASA and retired in April. In 2021, she was the NASA source selection official who picked SpaceX's Starship rocket for a $3 billion Artemis contract to land the first U.S. astronauts on the moon since 1972.
 
But why?
It's not like Musk is providing a public service or using his own money to play astronaut: he is using taxpayer and investor money to corner a market for profit, one that will end up benefitting few people aside from himself.
You have evidence of this?
Maybe you need to go learn how things work (see my signature)

"SpaceX doesn’t get any material grants from the Feds. The company wins contracts, and it is hard to argue SpaceX doesn’t deserve them. SpaceX pioneered reusable rockets and returned crewed transport capability to the U.S., beating Boeing in the process."

The federal government has paid SpaceX some $20 billion since 2008. The largest awards were for taking astronauts to and from the International Space Station, and resupplying the ISS. SpaceX has also won contracts to build a lunar-landing vehicle, and provide launch services to the Defense Department, among others.

NASA could not have come anywhere near getting the services being supplied by SpaceX for just US$20 billion over 16 years. Take a look how much the Starliner and SLS boondoggles cost to develop...

SLS - US$26.4 billion on SLS development since 2011, through 2023, in nominal dollars. This is equivalent to $32 billion in 2024 dollars.

Starliner - In 2014, NASA awarded Boeing a fixed-price contract of $4.2 billion to develop and operate Starliner. It has been an utter failure. The test mission to the ISS failed to reach the station, and rather than have a second test flight, they decided to risk two astronauts, and ended up stranding them there... And now SpaceX is in the process of rescuing them:ROFLMAO::ROFLMAO::ROFLMAO:.

No, the ROI on the money the US government has invested in SpaceX an been more than they could have hoped for. Its been a real bargain for them. I expect the money they invest in Blue Origin will reap similar rewards. Those who criticise that expenditure, people like you, and a unique person and Gulliver Foyle have absolutely no ******* idea what you are talking about.


We won't see any of the money he ought to be paying in taxes, but we DO have the right to give him ◊◊◊◊ 24/7 (for how much longer is the question).
So I don't see why we get ◊◊◊◊ from you for pointing out that he has way overpromised what SpaceX would do, and keeps failing at it: as you pointed our, he is paid to develop a Lunar lander, not to make reusable rockets - that's his thing to make more money for him. So by that metritm the last test was a failure for taxpayers, a win for him, personally.

Either SpaceX can show the results it promised, or it can't - we don't have to accept explanations or excuses when it's our taxes paying for it.
Really? That's what you're going with?

Lets say you are paying a contracting company to develop a product for you. Are you going to demand that contracting company devotes ALL of their resources and all of their staff to exclusively work on YOUR project? Because I can tell you that if you demanded that from my contracting business, I would tell you to shove you project where the monkey put the nut!
 
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