[Merged] SpaceX’s Starship Rocket Explodes After Launch/Starship hop - Page 5

Belz... · 5th March 2021, 10:02 AM

Originally Posted by 3point14

Okay, apparently you have a handle on it. I haven't then energy to work out why you're saying what you're saying.

Have a lovely day.

What's got you confused? I'm saying that so long as the project focuses on precise goals, and thus fewer flights, they can insure that launches are safe for the crew. If and when it becomes commercial, that might no longer be true. Launching rockets is inherently dangerous; much more so than with planes.

3point14 · 5th March 2021, 10:07 AM

Originally Posted by Belz...

What's got you confused? I'm saying that so long as the project focuses on precise goals, and thus fewer flights, they can insure that launches are safe for the crew. If and when it becomes commercial, that might no longer be true. Launching rockets is inherently dangerous; much more so than with planes.

Yeah, I'm really not going to try to unpick it. You seem to think you have a handle on it, so I'll leave you with that.

Belz... · 5th March 2021, 10:08 AM

Originally Posted by 3point14

Yeah, I'm really not going to try to unpick it. You seem to think you have a handle on it, so I'll leave you with that.

I don't understand what your beef is. Am I wrong about this? If so, why?

You've now posted twice to tell me you won't engage me. If you're going to post, why not post substantively?

3point14 · 5th March 2021, 10:14 AM

Originally Posted by Belz...

I don't understand what your beef is. Am I wrong about this? If so, why?

You've now posted twice to tell me you won't engage me. If you're going to post, why not post substantively?

Because you started with this:

Originally Posted by Belz...

Sure, if Musk ever comes around to try to implement routine orbital flights, I'd agree. But as I mentioned, NASA has a single manned launch incident (Challenger). So it's feasible at least so long as there are few flights done with the utmost of care.

Note the 'if' at the beginning there. There is no 'if' there That's exactly what he's trying to do now, with this project and this tech, right now. That's why I'm so confused. You say you have a handle on what he's doing, but you, at the same time seem to think he's not doing that.

Musk is currently trying to impliment routine orbital flights. You seem to think there's an 'if' in that statement. There isn't. But you also tell me you know what he's doing.

Belz... · 5th March 2021, 10:22 AM

Originally Posted by 3point14

Note the 'if' at the beginning there. There is no 'if' there That's exactly what he's trying to do now, with this project and this tech, right now.

Yes but that doesn't mean he'll succeed. I hope he does, but there are giant hurdles to clear from here to there. He may realise that before getting to that point, and abandon the project, focusing on more 'classic' operations. Hence the 'if'. At this point I think we're several steps behind that.

3point14 · 5th March 2021, 10:25 AM

Originally Posted by Belz...

Yes but that doesn't mean he'll succeed. I hope he does, but there are giant hurdles to clear from here to there. He may realise that before getting to that point, and abandon the project, focusing on more 'classic' operations. Hence the 'if'.

No, it doesn't, but that's not what you said.

You said:

"Sure, if Musk ever comes around to try to implement routine orbital flights"

Which is just in opposition to reality as that's exactly what he's trying to do. There's no 'if' in that sentence if you want it to match what's Musk is actually doing, which is: Trying to implement routine orbital flights.

Perhaps you can't see why your statement is so confusing. Perhaps I'm banging my head against a brick wall. Perhaps I'm going to take an asprin and have a lie down. Who knows.

Meadmaker · 5th March 2021, 10:27 AM

Originally Posted by Belz...

Sure, if Musk ever comes around to try to implement routine orbital flights, I'd agree. But as I mentioned, NASA has a single manned launch incident (Challenger). So it's feasible at least so long as there are few flights done with the utmost of care.

They also had a single landing incident, and one incident where people died in a test that was never intended to fly. I think the Russians have had only one fatal accident.

Four incidents with fatalities isn't huge, considering the nature of the endeavor, but for consumer use, it's kind of extreme. Commercial flights will need to have a much better track record than NASA has had if they want to be commonplace.

ETA: I just looked it up. 553 people have made it into Earth orbit. 21 have died in space related accidents. Before space flight becomes "routine", Musk et. al. will have to do a lot better.

Belz... · 5th March 2021, 10:33 AM

Originally Posted by 3point14

No, it doesn't, but that's not what you said.

You said:

"Sure, if Musk ever comes around to try to implement routine orbital flights"

Which is just in opposition to reality as that's exactly what he's trying to do.

That's what he's planning to do, once the technology is sufficiently developed. But correct me if I'm wrong, the Starship is supposed to serve other missions as well such as a Mars mission, which certainly isn't routine anywhere in the near future. Some of the goals of the design might be pursued, and others not. We're not there yet. Right now we're trying to make the damned thing work.

I don't know why it was necessary for you to get personal, considering how trivial of a disagreement this is.

Belz... · 5th March 2021, 10:33 AM

Originally Posted by Meadmaker

They also had a single landing incident, and one incident where people died in a test that was never intended to fly. I think the Russians have had only one fatal accident.

Four incidents with fatalities isn't huge, considering the nature of the endeavor, but for consumer use, it's kind of extreme.

We were specifically discussing launches, not landings or electrical tests. That's why I didn't mention Columbia or Apollo 1.

Otherwise I agree with you.

3point14 · 5th March 2021, 10:37 AM

Originally Posted by Belz...

That's what he's planning to do, once the technology is sufficiently developed. But correct me if I'm wrong, the Starship is supposed to serve other missions as well such as a Mars mission, which certainly isn't routine anywhere in the near future

It pretty much is. It would take six consecutive flights to refuel a Starship to get it to Mars. Currently planned to be one after the other in rapid succession. The Mars plan absolutely needs the launches to be routine.

Quote:

Some of the goals of the design might be pursued, and others not. We're not there yet. Right now we're trying to make the damned thing work.

Yes, and by 'work', Musk means achieve routine orbital flight.

Quote:

I don't know why it was necessary for you to get personal, considering how trivial of a disagreement this is.

Not personal, just exasperated. You started with a statement that seemed to indicate that you didn't know the goals of the project. You then told me that you did know the goals of the project You've since demonstrated that you don't know the goals of the project. It was exhausting. I tried to give up but you really, really wanted an answer.

I'm going to go and have that lie down now.

Belz... · 5th March 2021, 10:42 AM

Originally Posted by 3point14

It pretty much is. It would take six consecutive flights to refuel a Starship to get it to Mars. Currently planned to be one after the other in rapid succession. The Mars plan absolutely needs the launches to be routine.

Ok maybe we're just disagreeing on what 'routine' means. I don't mean 'routine' like a shuttle launch. I mean 'routine' like a 777 takeoff.

Quote:

Not personal, just exasperated.

There's no need for that. I said something that you were confused about or disagreed with and we're untangling it. It's a discussion. Presumably you have some of those with other people and encounter similar problems without having to lie down afterwards.

Quote:

You've since demonstrated that you don't know the goals of the project.

Where have I done this? Again this disagreement is due to us having different interpretations of what current launch objectives are. Musk has got to crawl before he walks. For now we're still in the very early stages; we're far from a possible moon mission with SpaceX, something that was done over 50 years ago. Before we try to get into routine launches, there are intermediate steps; lots of them, and they may discover along the way that what they ultimately wanted to do is either impossible or not worth the costs, and use the design and tech for more modest goals.

3point14 · 5th March 2021, 10:49 AM

My apologies if I came across as peeved.

RecoveringYuppy · 5th March 2021, 10:51 AM

Originally Posted by 3point14

Okay, apparently you have a handle on it. I haven't then energy to work out why you're saying what you're saying.

Have a lovely day.

I think he is simply saying that there is no reason they can't match NASA's safety record. As long as SpaceX is in the same of mode of limited flights, no need to consider an accident a given as opposed to a potentiality. The "one in a million" comparison to airliners isn't relevant until SpaceX is flying on the scale of airliners.

ETA: Sorry, I hadn't noticed the conversation went on to another page beyond the post I replied to.

Belz... · 5th March 2021, 10:53 AM

Originally Posted by 3point14

My apologies if I came across as peeved.

Meh, don't worry about it.

Belz... · 5th March 2021, 10:54 AM

Originally Posted by RecoveringYuppy

I think he is simply saying that there is no reason they can't match NASA's safety record. As long as SpaceX is in the same of mode of limited flights, no need to consider an accident a given as opposed to a potentiality. The "one in a million" comparison to airliners isn't relevant until SpaceX is flying on the scale of airliners.

ETA: Sorry, I hadn't noticed the conversation went on to another page beyond the post I replied to.

No, that's good. It's a better summary than I managed.

3point14 · 5th March 2021, 10:55 AM

Originally Posted by Belz...

No, that's good. It's a better summary than I managed.

I probably should have worked that out.

It's been a long week. Hell, it's been a long year.

I shall go sit in the corner and have a serious word with myself. Sorry.

Belz... · 5th March 2021, 11:00 AM

Originally Posted by 3point14

It's been a long week. Hell, it's been a long year.

Yeah, tell me about it. It's a good thing I'm generally antisocial...

smartcooky · 5th March 2021, 11:50 AM

Originally Posted by Meadmaker

They also had a single landing incident, and one incident where people died in a test that was never intended to fly. I think the Russians have had only one fatal accident.

Two during space operations

24 April 1967: The astronaut aboard Soyuz 1m Vladimir Komarov dies when his parachute failed

30 June 1971: The crew of Soyuz 11, Georgy Dobrovolsky, Viktor Patsayev and Vladislav Volkov, died from lack of oxygen after a cabin vent valve opened during separation from the Salyut 1 space station

They also had numerous other fatal accidents including the massive explosion of a Vostok rocket that killed 48 people in 1980, and the earlier Nedelin Disaster in October 1960 where the second stage of an R-16 rocket ignited on the launch pad killing up to 300.

Belz... · 5th March 2021, 12:21 PM

Let's just say that 'soviet' wasn't much of a seal of quality.

3point14 · 5th March 2021, 12:26 PM

Originally Posted by Belz...

Let's just say that 'soviet' wasn't much of a seal of quality.

They were pretty good at innovation though. And their safety record probably compares quite well with the US one due to the two shuttle disasters. (not entirely sure about that though)

They also made full-flow staged combustion when the US had, I think, deemed them impossible.

And Soyuz was the only game in human rated spaceflight for years

The N1, however, was a very, very expensive firework.

Meadmaker · 5th March 2021, 02:58 PM

Originally Posted by smartcooky

Two during space operations

24 April 1967: The astronaut aboard Soyuz 1m Vladimir Komarov dies when his parachute failed

30 June 1971: The crew of Soyuz 11, Georgy Dobrovolsky, Viktor Patsayev and Vladislav Volkov, died from lack of oxygen after a cabin vent valve opened during separation from the Salyut 1 space station

They also had numerous other fatal accidents including the massive explosion of a Vostok rocket that killed 48 people in 1980, and the earlier Nedelin Disaster in October 1960 where the second stage of an R-16 rocket ignited on the launch pad killing up to 300.

Yikes. I had never heard of those launchpad deaths.

It all seems kind of dangerous to me.

Belz... · 5th March 2021, 03:40 PM

Originally Posted by Meadmaker

Yikes. I had never heard of those launchpad deaths.

It all seems kind of dangerous to me.

That's why it's generally -- but not always -- suggested to not stay on the launch pad when the rocket goes off.

GlennB · 5th March 2021, 03:45 PM

Originally Posted by Belz...

That's why it's generally -- but not always -- suggested to not stay on the launch pad when the rocket goes off.

But being a passenger on the landing pad when the rocket lands is pretty much inevitable. My impression is that SpaceX soft landings pose much more of a danger than launchings. Why the recent stress on launch in this thread is baffling.

Belz... · 5th March 2021, 04:47 PM

Originally Posted by GlennB

But being a passenger on the landing pad when the rocket lands is pretty much inevitable. My impression is that SpaceX soft landings pose much more of a danger than launchings. Why the recent stress on launch in this thread is baffling.

Sorry I can't hear you. I've been on the pad at too many launches.

Roboramma · 5th March 2021, 06:39 PM

Originally Posted by Belz...

That's a very good point.

Thanks!

Quote:

But as I said, fundamentally, the last thing you want your rocket to do is explode. It's not a small matter. If I were the CEO of that company I wouldn't be happy with yesterday's events.

Well, there's happy and then there's happy, I guess. You're definitely right that it would be better if the thing didn't explode. I think they're at the point now where they don't really know enough about what they're doing to expect them not to explode (Musk was saying as much at least before SN9, I think). Getting the thing to turn over for the bellyflop maneuver was already a big deal, as I understand it, so focusing on that and working on perfecting the other aspects of landing on later iterations makes sense to me.

But I definitely agree that everyone at SpaceX would have been a lot happier with an unmitigated success and no explosion. I would too!

I'm only saying that incremental progress is still progress, and as far as I can tell it seems like they're progressing about as fast as they expected to. I think the people at SpaceX out to be pretty happy about that, given the difficulty of what they're trying to achieve.

Roboramma · 5th March 2021, 06:50 PM

Originally Posted by GlennB

But being a passenger on the landing pad when the rocket lands is pretty much inevitable. My impression is that SpaceX soft landings pose much more of a danger than launchings. Why the recent stress on launch in this thread is baffling.

That's a good point. The difficultly of launching rockets safely enough for commercial passenger flights is pretty high, but landing them again in the way SpaceX does at least seems to be even harder.

Not to say they can't achieve it, but yeah it's a very difficult undertaking.

One thing that I think will help is if they can get enough rockets flying for other purposes first to really work out the issues with it. If you're launching hundreds of times/year (without passengers), you have plenty of chances to find the problems that might come up and fix them.

Belz... · 5th March 2021, 07:37 PM

Originally Posted by Roboramma

That's a good point. The difficultly of launching rockets safely enough for commercial passenger flights is pretty high, but landing them again in the way SpaceX does at least seems to be even harder.

Not to say they can't achieve it, but yeah it's a very difficult undertaking.

Quite. The shuttles were amazingly cool, but they turned out to be not cost-effective. I'm not sure yet that reusable rockets will be better in that department.

smartcooky · 5th March 2021, 07:46 PM

Originally Posted by GlennB

But being a passenger on the landing pad when the rocket lands is pretty much inevitable. My impression is that SpaceX soft landings pose much more of a danger than launchings. Why the recent stress on launch in this thread is baffling.

Care to elaborate on why you think that?

RecoveringYuppy · 5th March 2021, 08:35 PM

Originally Posted by GlennB

But being a passenger on the landing pad when the rocket lands is pretty much inevitable. My impression is that SpaceX soft landings pose much more of a danger than launchings. Why the recent stress on launch in this thread is baffling.

Originally Posted by smartcooky

Care to elaborate on why you think that?

When would passengers experience this kind of landing?

Roboramma · 5th March 2021, 09:25 PM

Originally Posted by RecoveringYuppy

When would passengers experience this kind of landing?

Isn't that the plan with Starship? Or is the idea still that Starship would launch with a Dragon capsule as payload which can then do reentry on its own?

That probably does make more sense, and even if it's not the plan now, it could be done that way if landing can't be made reliable enough for human safety.

(I apologize for not looking this up myself, my VPN subscription expired and I've yet to renew it, which means I'm currently stuck behind the Chinese firewall, so no google, or wikipedia...)

RecoveringYuppy · 5th March 2021, 10:10 PM

Originally Posted by Roboramma

Isn't that the plan with Starship? Or is the idea still that Starship would launch with a Dragon capsule as payload which can then do reentry on its own?

That probably does make more sense, and even if it's not the plan now, it could be done that way if landing can't be made reliable enough for human safety.

(I apologize for not looking this up myself, my VPN subscription expired and I've yet to renew it, which means I'm currently stuck behind the Chinese firewall, so no google, or wikipedia...)

Other than the Dragon capsule, I'm not sure of the details of what they have in mind for passengers.

I haven't been paying enough attention to this recently, so let me ask some stupid questions. SN10 was a test of the first stage, correct? I think there are only 3 Raptor engines in this vehicle and I think the full two stage configuration would have six. This was testing the recovery of the first stage, wasn't it? If this had been a real flight the passengers would have been on the second or third stage and it wouldn't matter that their first stage had exploded long after they were done with it.

crescent · 5th March 2021, 10:57 PM

Originally Posted by RecoveringYuppy

Other than the Dragon capsule, I'm not sure of the details of what they have in mind for passengers.

I haven't been paying enough attention to this recently, so let me ask some stupid questions. SN10 was a test of the first stage, correct? I think there are only 3 Raptor engines in this vehicle and I think the full two stage configuration would have six. This was testing the recovery of the first stage, wasn't it? If this had been a real flight the passengers would have been on the second or third stage and it wouldn't matter that their first stage had exploded long after they were done with it.

No - this was testing of the second stage of the two stage rocket. They've got a couple of first stage boosters under construction.

smartcooky · 5th March 2021, 11:22 PM

Originally Posted by RecoveringYuppy

I haven't been paying enough attention to this recently, so let me ask some stupid questions. SN10 was a test of the first stage, correct?

No, SN10 is not even remotely like any of the Starship stages, although it looks similar in shape to what the second stage is expected to look like. (The first stage is the superheavy booster, which will re-enter and land in much the same way as the Falcon 9 booster - tail first, with an "entry burn" and a "landing burn")

SN10 is a test article, nothing more. It has much the same sort of role that the SpaceX "Grasshopper" had, i.e. proving the concept that autonomously hovering and landing a rocket at a precise location was feasible. It is purely for testing the concept of free-falling towards a landing in which the second stage will flip from near horizontal to vertical, as we saw it doing. The reason for this is that the intention is for the Starship second stage to re-enter from orbit in that nose-up belly first attitude, shedding off orbital velocity until comes down to terminal velocity.

The reason for the two different methods is simple... the first stage only has to re-enter at speeds of around 6,000 kph - that is relatively low, so the engine bells and associated structure do not have to withstand a great amount of heating - the reason for the entry burn is to shed off speed to limit that heating. However, the second stage will be entering the earth's atmosphere at orbital velocity, about 28,000 kph - no entry burn, and the kicker is that convective heating isn't just proportional to velocity, its not even velocity squared, its velocity cubed!! - so double the entry speed from 6,000 to 12,000 kph, and the heating effect is eight times greater than at 6,000, double it again to 24,000 kph and the heating effect is 64 times greater than at 6,000 kph*. Obviously, the thrust structure would not be able to withstand this; any attempt to re-enter tail first at those speed would result in the destruction of the vehicle. SpaceX had to come up with a different way to re-enter and land the second stage.

* This is the simplified version. There is also radiative heating that needs to be considered, and it is proportional to the eighth power of velocity.

GlennB · 6th March 2021, 03:02 AM

Originally Posted by smartcooky

Care to elaborate on why you think that?

SN8/9/10 have all experienced disaster at or just after landing. In addition, launch technology is well established, while soft landings are novel. Musk said, of this very technology, something like "There will be some holes in the ground along the way", and he wasn't talking about launches.

smartcooky · 6th March 2021, 03:28 AM

Originally Posted by GlennB

SN8/9/10 have all experienced disaster at or just after landing. In addition, launch technology is well established, while soft landings are novel. Musk said, of this very technology, something like "There will be some holes in the ground along the way", and he wasn't talking about launches.

Ok, so you are specifically, talking only about these test article landings and not rocket landings in general.

Belz... · 6th March 2021, 06:25 AM

Originally Posted by smartcooky

No, SN10 is not even remotely like any of the Starship stages, although it looks similar in shape to what the second stage is expected to look like. (The first stage is the superheavy booster, which will re-enter and land in much the same way as the Falcon 9 booster - tail first, with an "entry burn" and a "landing burn")

SN10 is a test article, nothing more. It has much the same sort of role that the SpaceX "Grasshopper" had, i.e. proving the concept that autonomously hovering and landing a rocket at a precise location was feasible. It is purely for testing the concept of free-falling towards a landing in which the second stage will flip from near horizontal to vertical, as we saw it doing. The reason for this is that the intention is for the Starship second stage to re-enter from orbit in that nose-up belly first attitude, shedding off orbital velocity until comes down to terminal velocity.

The reason for the two different methods is simple... the first stage only has to re-enter at speeds of around 6,000 kph - that is relatively low, so the engine bells and associated structure do not have to withstand a great amount of heating - the reason for the entry burn is to shed off speed to limit that heating. However, the second stage will be entering the earth's atmosphere at orbital velocity, about 28,000 kph - no entry burn, and the kicker is that convective heating isn't just proportional to velocity, its not even velocity squared, its velocity cubed!! - so double the entry speed from 6,000 to 12,000 kph, and the heating effect is eight times greater than at 6,000, double it again to 24,000 kph and the heating effect is 64 times greater than at 6,000 kph*. Obviously, the thrust structure would not be able to withstand this; any attempt to re-enter tail first at those speed would result in the destruction of the vehicle. SpaceX had to come up with a different way to re-enter and land the second stage.

* This is the simplified version. There is also radiative heating that needs to be considered, and it is proportional to the eighth power of velocity.

What do you mean by no entry burn? At that speed there has to be one, no?

Belz... · 6th March 2021, 09:32 AM

Anyway we need to rename the thread to "Starship Blew Hop".

RecoveringYuppy · 6th March 2021, 09:58 AM

Thanks crescent and smartcooky.

RecoveringYuppy · 6th March 2021, 10:00 AM

Originally Posted by Belz...

What do you mean by no entry burn? At that speed there has to be one, no?

Just guessing, but in normal operations it probably detaches before the orbit is circularized so it's orbit still intersects the atmosphere. And probably pretty close to intersecting the surface of the Earth.

ETA: No, on reading the Wikipedia the current plan is for the second stage to make orbit, so I'm confused about the no burn comment too.

3point14 · 6th March 2021, 10:04 AM

Originally Posted by Belz...

What do you mean by no entry burn? At that speed there has to be one, no?

There'll be a re-entry burn.

I think he means there won't be a burn after re-entry to reduce speed to reduce shock heating.

5th March 2021, 10:02 AM	#161
Belz... Fiend God Join Date: Oct 2005 Location: In a post-fact world Posts: 96,875	Originally Posted by 3point14 Okay, apparently you have a handle on it. I haven't then energy to work out why you're saying what you're saying. Have a lovely day. What's got you confused? I'm saying that so long as the project focuses on precise goals, and thus fewer flights, they can insure that launches are safe for the crew. If and when it becomes commercial, that might no longer be true. Launching rockets is inherently dangerous; much more so than with planes.
	__________________ Master of the Shining Darkness "My views are nonsense. So what?" - BobTheCoward

5th March 2021, 10:07 AM	#162
3point14 Pi Join Date: Nov 2005 Posts: 21,569	Originally Posted by Belz... What's got you confused? I'm saying that so long as the project focuses on precise goals, and thus fewer flights, they can insure that launches are safe for the crew. If and when it becomes commercial, that might no longer be true. Launching rockets is inherently dangerous; much more so than with planes. Yeah, I'm really not going to try to unpick it. You seem to think you have a handle on it, so I'll leave you with that.
3point14 Pi Join Date: Nov 2005 Posts: 21,569	__________________ Up the River! Anyone that wraps themselves in the Union Flag and also lives in tax exile is a [redacted]

5th March 2021, 10:08 AM	#163
Belz... Fiend God Join Date: Oct 2005 Location: In a post-fact world Posts: 96,875	Originally Posted by 3point14 Yeah, I'm really not going to try to unpick it. You seem to think you have a handle on it, so I'll leave you with that. I don't understand what your beef is. Am I wrong about this? If so, why? You've now posted twice to tell me you won't engage me. If you're going to post, why not post substantively?
	__________________ Master of the Shining Darkness "My views are nonsense. So what?" - BobTheCoward

5th March 2021, 10:14 AM	#164
3point14 Pi Join Date: Nov 2005 Posts: 21,569	Originally Posted by Belz... I don't understand what your beef is. Am I wrong about this? If so, why? You've now posted twice to tell me you won't engage me. If you're going to post, why not post substantively? Because you started with this: Originally Posted by Belz... Sure, if Musk ever comes around to try to implement routine orbital flights, I'd agree. But as I mentioned, NASA has a single manned launch incident (Challenger). So it's feasible at least so long as there are few flights done with the utmost of care. Note the 'if' at the beginning there. There is no 'if' there That's exactly what he's trying to do now, with this project and this tech, right now. That's why I'm so confused. You say you have a handle on what he's doing, but you, at the same time seem to think he's not doing that. Musk is currently trying to impliment routine orbital flights. You seem to think there's an 'if' in that statement. There isn't. But you also tell me you know what he's doing.
3point14 Pi Join Date: Nov 2005 Posts: 21,569	__________________ Up the River! Anyone that wraps themselves in the Union Flag and also lives in tax exile is a [redacted]

5th March 2021, 10:22 AM	#165
Belz... Fiend God Join Date: Oct 2005 Location: In a post-fact world Posts: 96,875	Originally Posted by 3point14 Note the 'if' at the beginning there. There is no 'if' there That's exactly what he's trying to do now, with this project and this tech, right now. Yes but that doesn't mean he'll succeed. I hope he does, but there are giant hurdles to clear from here to there. He may realise that before getting to that point, and abandon the project, focusing on more 'classic' operations. Hence the 'if'. At this point I think we're several steps behind that.
	__________________ Master of the Shining Darkness "My views are nonsense. So what?" - BobTheCoward Last edited by Belz...; 5th March 2021 at 10:23 AM.

5th March 2021, 10:25 AM	#166
3point14 Pi Join Date: Nov 2005 Posts: 21,569	Originally Posted by Belz... Yes but that doesn't mean he'll succeed. I hope he does, but there are giant hurdles to clear from here to there. He may realise that before getting to that point, and abandon the project, focusing on more 'classic' operations. Hence the 'if'. No, it doesn't, but that's not what you said. You said: "Sure, if Musk ever comes around to try to implement routine orbital flights" Which is just in opposition to reality as that's exactly what he's trying to do. There's no 'if' in that sentence if you want it to match what's Musk is actually doing, which is: Trying to implement routine orbital flights. Perhaps you can't see why your statement is so confusing. Perhaps I'm banging my head against a brick wall. Perhaps I'm going to take an asprin and have a lie down. Who knows.
3point14 Pi Join Date: Nov 2005 Posts: 21,569	__________________ Up the River! Anyone that wraps themselves in the Union Flag and also lives in tax exile is a [redacted]

5th March 2021, 10:27 AM	#167
Meadmaker Guest Join Date: Apr 2004 Posts: 29,033	Originally Posted by Belz... Sure, if Musk ever comes around to try to implement routine orbital flights, I'd agree. But as I mentioned, NASA has a single manned launch incident (Challenger). So it's feasible at least so long as there are few flights done with the utmost of care. They also had a single landing incident, and one incident where people died in a test that was never intended to fly. I think the Russians have had only one fatal accident. Four incidents with fatalities isn't huge, considering the nature of the endeavor, but for consumer use, it's kind of extreme. Commercial flights will need to have a much better track record than NASA has had if they want to be commonplace. ETA: I just looked it up. 553 people have made it into Earth orbit. 21 have died in space related accidents. Before space flight becomes "routine", Musk et. al. will have to do a lot better.
Meadmaker Guest Join Date: Apr 2004 Posts: 29,033	Last edited by Meadmaker; 5th March 2021 at 10:32 AM.

5th March 2021, 10:33 AM	#168
Belz... Fiend God Join Date: Oct 2005 Location: In a post-fact world Posts: 96,875	Originally Posted by 3point14 No, it doesn't, but that's not what you said. You said: "Sure, if Musk ever comes around to try to implement routine orbital flights" Which is just in opposition to reality as that's exactly what he's trying to do. That's what he's planning to do, once the technology is sufficiently developed. But correct me if I'm wrong, the Starship is supposed to serve other missions as well such as a Mars mission, which certainly isn't routine anywhere in the near future. Some of the goals of the design might be pursued, and others not. We're not there yet. Right now we're trying to make the damned thing work. I don't know why it was necessary for you to get personal, considering how trivial of a disagreement this is.
	__________________ Master of the Shining Darkness "My views are nonsense. So what?" - BobTheCoward

5th March 2021, 10:33 AM	#169
Belz... Fiend God Join Date: Oct 2005 Location: In a post-fact world Posts: 96,875	Originally Posted by Meadmaker They also had a single landing incident, and one incident where people died in a test that was never intended to fly. I think the Russians have had only one fatal accident. Four incidents with fatalities isn't huge, considering the nature of the endeavor, but for consumer use, it's kind of extreme. We were specifically discussing launches, not landings or electrical tests. That's why I didn't mention Columbia or Apollo 1. Otherwise I agree with you.
	__________________ Master of the Shining Darkness "My views are nonsense. So what?" - BobTheCoward Last edited by Belz...; 5th March 2021 at 10:37 AM.

5th March 2021, 10:37 AM	#170
3point14 Pi Join Date: Nov 2005 Posts: 21,569	Originally Posted by Belz... That's what he's planning to do, once the technology is sufficiently developed. But correct me if I'm wrong, the Starship is supposed to serve other missions as well such as a Mars mission, which certainly isn't routine anywhere in the near future It pretty much is. It would take six consecutive flights to refuel a Starship to get it to Mars. Currently planned to be one after the other in rapid succession. The Mars plan absolutely needs the launches to be routine. Quote: Some of the goals of the design might be pursued, and others not. We're not there yet. Right now we're trying to make the damned thing work. Yes, and by 'work', Musk means achieve routine orbital flight. Quote: I don't know why it was necessary for you to get personal, considering how trivial of a disagreement this is. Not personal, just exasperated. You started with a statement that seemed to indicate that you didn't know the goals of the project. You then told me that you did know the goals of the project You've since demonstrated that you don't know the goals of the project. It was exhausting. I tried to give up but you really, really wanted an answer. I'm going to go and have that lie down now.
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5th March 2021, 10:42 AM	#171
Belz... Fiend God Join Date: Oct 2005 Location: In a post-fact world Posts: 96,875	Originally Posted by 3point14 It pretty much is. It would take six consecutive flights to refuel a Starship to get it to Mars. Currently planned to be one after the other in rapid succession. The Mars plan absolutely needs the launches to be routine. Ok maybe we're just disagreeing on what 'routine' means. I don't mean 'routine' like a shuttle launch. I mean 'routine' like a 777 takeoff. Quote: Not personal, just exasperated. There's no need for that. I said something that you were confused about or disagreed with and we're untangling it. It's a discussion. Presumably you have some of those with other people and encounter similar problems without having to lie down afterwards. Quote: You've since demonstrated that you don't know the goals of the project. Where have I done this? Again this disagreement is due to us having different interpretations of what current launch objectives are. Musk has got to crawl before he walks. For now we're still in the very early stages; we're far from a possible moon mission with SpaceX, something that was done over 50 years ago. Before we try to get into routine launches, there are intermediate steps; lots of them, and they may discover along the way that what they ultimately wanted to do is either impossible or not worth the costs, and use the design and tech for more modest goals.
	__________________ Master of the Shining Darkness "My views are nonsense. So what?" - BobTheCoward

5th March 2021, 10:49 AM	#172
3point14 Pi Join Date: Nov 2005 Posts: 21,569	My apologies if I came across as peeved.
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5th March 2021, 10:51 AM	#173
RecoveringYuppy Penultimate Amazing Join Date: Nov 2006 Posts: 14,185	Originally Posted by 3point14 Okay, apparently you have a handle on it. I haven't then energy to work out why you're saying what you're saying. Have a lovely day. I think he is simply saying that there is no reason they can't match NASA's safety record. As long as SpaceX is in the same of mode of limited flights, no need to consider an accident a given as opposed to a potentiality. The "one in a million" comparison to airliners isn't relevant until SpaceX is flying on the scale of airliners. ETA: Sorry, I hadn't noticed the conversation went on to another page beyond the post I replied to.
	Last edited by RecoveringYuppy; 5th March 2021 at 10:52 AM.

5th March 2021, 10:53 AM	#174
Belz... Fiend God Join Date: Oct 2005 Location: In a post-fact world Posts: 96,875	Originally Posted by 3point14 My apologies if I came across as peeved. Meh, don't worry about it.
	__________________ Master of the Shining Darkness "My views are nonsense. So what?" - BobTheCoward

5th March 2021, 10:54 AM	#175
Belz... Fiend God Join Date: Oct 2005 Location: In a post-fact world Posts: 96,875	Originally Posted by RecoveringYuppy I think he is simply saying that there is no reason they can't match NASA's safety record. As long as SpaceX is in the same of mode of limited flights, no need to consider an accident a given as opposed to a potentiality. The "one in a million" comparison to airliners isn't relevant until SpaceX is flying on the scale of airliners. ETA: Sorry, I hadn't noticed the conversation went on to another page beyond the post I replied to. No, that's good. It's a better summary than I managed.
	__________________ Master of the Shining Darkness "My views are nonsense. So what?" - BobTheCoward

5th March 2021, 10:55 AM	#176
3point14 Pi Join Date: Nov 2005 Posts: 21,569	Originally Posted by Belz... No, that's good. It's a better summary than I managed. I probably should have worked that out. It's been a long week. Hell, it's been a long year. I shall go sit in the corner and have a serious word with myself. Sorry.
3point14 Pi Join Date: Nov 2005 Posts: 21,569	__________________ Up the River! Anyone that wraps themselves in the Union Flag and also lives in tax exile is a [redacted]

5th March 2021, 11:00 AM	#177
Belz... Fiend God Join Date: Oct 2005 Location: In a post-fact world Posts: 96,875	Originally Posted by 3point14 It's been a long week. Hell, it's been a long year. Yeah, tell me about it. It's a good thing I'm generally antisocial...
	__________________ Master of the Shining Darkness "My views are nonsense. So what?" - BobTheCoward

5th March 2021, 11:50 AM	#178
smartcooky Penultimate Amazing Join Date: Oct 2012 Location: Nelson, New Zealand Posts: 23,587	Originally Posted by Meadmaker They also had a single landing incident, and one incident where people died in a test that was never intended to fly. I think the Russians have had only one fatal accident. Two during space operations 24 April 1967: The astronaut aboard Soyuz 1m Vladimir Komarov dies when his parachute failed 30 June 1971: The crew of Soyuz 11, Georgy Dobrovolsky, Viktor Patsayev and Vladislav Volkov, died from lack of oxygen after a cabin vent valve opened during separation from the Salyut 1 space station They also had numerous other fatal accidents including the massive explosion of a Vostok rocket that killed 48 people in 1980, and the earlier Nedelin Disaster in October 1960 where the second stage of an R-16 rocket ignited on the launch pad killing up to 300.
	__________________ What is Woke? It is a term that means "awakened to the needs of others". It means to be well-informed, thoughtful, compassionate, humble and kind. Woke people are keen to make the world a better, fairer place for everyone, But, unfortunately, it has also become a pejorative used by racists, homophobes and misogynists on the political right, to describe people who possess a fully functional moral compass. Last edited by smartcooky; 5th March 2021 at 12:15 PM.

5th March 2021, 12:21 PM	#179
Belz... Fiend God Join Date: Oct 2005 Location: In a post-fact world Posts: 96,875	Let's just say that 'soviet' wasn't much of a seal of quality.
	__________________ Master of the Shining Darkness "My views are nonsense. So what?" - BobTheCoward

5th March 2021, 12:26 PM	#180
3point14 Pi Join Date: Nov 2005 Posts: 21,569	Originally Posted by Belz... Let's just say that 'soviet' wasn't much of a seal of quality. They were pretty good at innovation though. And their safety record probably compares quite well with the US one due to the two shuttle disasters. (not entirely sure about that though) They also made full-flow staged combustion when the US had, I think, deemed them impossible. And Soyuz was the only game in human rated spaceflight for years The N1, however, was a very, very expensive firework.
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5th March 2021, 02:58 PM	#181
Meadmaker Guest Join Date: Apr 2004 Posts: 29,033	Originally Posted by smartcooky Two during space operations 24 April 1967: The astronaut aboard Soyuz 1m Vladimir Komarov dies when his parachute failed 30 June 1971: The crew of Soyuz 11, Georgy Dobrovolsky, Viktor Patsayev and Vladislav Volkov, died from lack of oxygen after a cabin vent valve opened during separation from the Salyut 1 space station They also had numerous other fatal accidents including the massive explosion of a Vostok rocket that killed 48 people in 1980, and the earlier Nedelin Disaster in October 1960 where the second stage of an R-16 rocket ignited on the launch pad killing up to 300. Yikes. I had never heard of those launchpad deaths. It all seems kind of dangerous to me.
Meadmaker Guest Join Date: Apr 2004 Posts: 29,033

5th March 2021, 03:40 PM	#182
Belz... Fiend God Join Date: Oct 2005 Location: In a post-fact world Posts: 96,875	Originally Posted by Meadmaker Yikes. I had never heard of those launchpad deaths. It all seems kind of dangerous to me. That's why it's generally -- but not always -- suggested to not stay on the launch pad when the rocket goes off.
	__________________ Master of the Shining Darkness "My views are nonsense. So what?" - BobTheCoward

5th March 2021, 03:45 PM	#183
GlennB Loggerheaded, earth-vexing fustilarian Join Date: Sep 2006 Location: Wales Posts: 29,715	Originally Posted by Belz... That's why it's generally -- but not always -- suggested to not stay on the launch pad when the rocket goes off. But being a passenger on the landing pad when the rocket lands is pretty much inevitable. My impression is that SpaceX soft landings pose much more of a danger than launchings. Why the recent stress on launch in this thread is baffling.
	__________________ "There ain't half been some clever bastards" - Ian Dury

5th March 2021, 04:47 PM	#184
Belz... Fiend God Join Date: Oct 2005 Location: In a post-fact world Posts: 96,875	Originally Posted by GlennB But being a passenger on the landing pad when the rocket lands is pretty much inevitable. My impression is that SpaceX soft landings pose much more of a danger than launchings. Why the recent stress on launch in this thread is baffling. Sorry I can't hear you. I've been on the pad at too many launches.
	__________________ Master of the Shining Darkness "My views are nonsense. So what?" - BobTheCoward

5th March 2021, 06:39 PM	#185
Roboramma Penultimate Amazing Join Date: Feb 2005 Location: Shanghai Posts: 15,178	Originally Posted by Belz... That's a very good point. Thanks! Quote: But as I said, fundamentally, the last thing you want your rocket to do is explode. It's not a small matter. If I were the CEO of that company I wouldn't be happy with yesterday's events. Well, there's happy and then there's happy, I guess. You're definitely right that it would be better if the thing didn't explode. I think they're at the point now where they don't really know enough about what they're doing to expect them not to explode (Musk was saying as much at least before SN9, I think). Getting the thing to turn over for the bellyflop maneuver was already a big deal, as I understand it, so focusing on that and working on perfecting the other aspects of landing on later iterations makes sense to me. But I definitely agree that everyone at SpaceX would have been a lot happier with an unmitigated success and no explosion. I would too! I'm only saying that incremental progress is still progress, and as far as I can tell it seems like they're progressing about as fast as they expected to. I think the people at SpaceX out to be pretty happy about that, given the difficulty of what they're trying to achieve.
	__________________ "... when people thought the Earth was flat, they were wrong. When people thought the Earth was spherical they were wrong. But if you think that thinking the Earth is spherical is just as wrong as thinking the Earth is flat, then your view is wronger than both of them put together." Isaac Asimov

5th March 2021, 06:50 PM	#186
Roboramma Penultimate Amazing Join Date: Feb 2005 Location: Shanghai Posts: 15,178	Originally Posted by GlennB But being a passenger on the landing pad when the rocket lands is pretty much inevitable. My impression is that SpaceX soft landings pose much more of a danger than launchings. Why the recent stress on launch in this thread is baffling. That's a good point. The difficultly of launching rockets safely enough for commercial passenger flights is pretty high, but landing them again in the way SpaceX does at least seems to be even harder. Not to say they can't achieve it, but yeah it's a very difficult undertaking. One thing that I think will help is if they can get enough rockets flying for other purposes first to really work out the issues with it. If you're launching hundreds of times/year (without passengers), you have plenty of chances to find the problems that might come up and fix them.
	__________________ "... when people thought the Earth was flat, they were wrong. When people thought the Earth was spherical they were wrong. But if you think that thinking the Earth is spherical is just as wrong as thinking the Earth is flat, then your view is wronger than both of them put together." Isaac Asimov

5th March 2021, 07:37 PM	#187
Belz... Fiend God Join Date: Oct 2005 Location: In a post-fact world Posts: 96,875	Originally Posted by Roboramma That's a good point. The difficultly of launching rockets safely enough for commercial passenger flights is pretty high, but landing them again in the way SpaceX does at least seems to be even harder. Not to say they can't achieve it, but yeah it's a very difficult undertaking. Quite. The shuttles were amazingly cool, but they turned out to be not cost-effective. I'm not sure yet that reusable rockets will be better in that department.
	__________________ Master of the Shining Darkness "My views are nonsense. So what?" - BobTheCoward

5th March 2021, 07:46 PM	#188
smartcooky Penultimate Amazing Join Date: Oct 2012 Location: Nelson, New Zealand Posts: 23,587	Originally Posted by GlennB But being a passenger on the landing pad when the rocket lands is pretty much inevitable. My impression is that SpaceX soft landings pose much more of a danger than launchings. Why the recent stress on launch in this thread is baffling. Care to elaborate on why you think that?
	__________________ What is Woke? It is a term that means "awakened to the needs of others". It means to be well-informed, thoughtful, compassionate, humble and kind. Woke people are keen to make the world a better, fairer place for everyone, But, unfortunately, it has also become a pejorative used by racists, homophobes and misogynists on the political right, to describe people who possess a fully functional moral compass. Last edited by smartcooky; 5th March 2021 at 07:50 PM.

5th March 2021, 08:35 PM	#189
RecoveringYuppy Penultimate Amazing Join Date: Nov 2006 Posts: 14,185	Originally Posted by GlennB But being a passenger on the landing pad when the rocket lands is pretty much inevitable. My impression is that SpaceX soft landings pose much more of a danger than launchings. Why the recent stress on launch in this thread is baffling. Originally Posted by smartcooky Care to elaborate on why you think that? When would passengers experience this kind of landing?

5th March 2021, 09:25 PM	#190
Roboramma Penultimate Amazing Join Date: Feb 2005 Location: Shanghai Posts: 15,178	Originally Posted by RecoveringYuppy When would passengers experience this kind of landing? Isn't that the plan with Starship? Or is the idea still that Starship would launch with a Dragon capsule as payload which can then do reentry on its own? That probably does make more sense, and even if it's not the plan now, it could be done that way if landing can't be made reliable enough for human safety. (I apologize for not looking this up myself, my VPN subscription expired and I've yet to renew it, which means I'm currently stuck behind the Chinese firewall, so no google, or wikipedia...)
	__________________ "... when people thought the Earth was flat, they were wrong. When people thought the Earth was spherical they were wrong. But if you think that thinking the Earth is spherical is just as wrong as thinking the Earth is flat, then your view is wronger than both of them put together." Isaac Asimov

5th March 2021, 10:10 PM	#191
RecoveringYuppy Penultimate Amazing Join Date: Nov 2006 Posts: 14,185	Originally Posted by Roboramma Isn't that the plan with Starship? Or is the idea still that Starship would launch with a Dragon capsule as payload which can then do reentry on its own? That probably does make more sense, and even if it's not the plan now, it could be done that way if landing can't be made reliable enough for human safety. (I apologize for not looking this up myself, my VPN subscription expired and I've yet to renew it, which means I'm currently stuck behind the Chinese firewall, so no google, or wikipedia...) Other than the Dragon capsule, I'm not sure of the details of what they have in mind for passengers. I haven't been paying enough attention to this recently, so let me ask some stupid questions. SN10 was a test of the first stage, correct? I think there are only 3 Raptor engines in this vehicle and I think the full two stage configuration would have six. This was testing the recovery of the first stage, wasn't it? If this had been a real flight the passengers would have been on the second or third stage and it wouldn't matter that their first stage had exploded long after they were done with it.

5th March 2021, 10:57 PM	#192
crescent Philosopher Join Date: Jul 2011 Location: Colorado Posts: 5,386	Originally Posted by RecoveringYuppy Other than the Dragon capsule, I'm not sure of the details of what they have in mind for passengers. I haven't been paying enough attention to this recently, so let me ask some stupid questions. SN10 was a test of the first stage, correct? I think there are only 3 Raptor engines in this vehicle and I think the full two stage configuration would have six. This was testing the recovery of the first stage, wasn't it? If this had been a real flight the passengers would have been on the second or third stage and it wouldn't matter that their first stage had exploded long after they were done with it. No - this was testing of the second stage of the two stage rocket. They've got a couple of first stage boosters under construction.

5th March 2021, 11:22 PM	#193
smartcooky Penultimate Amazing Join Date: Oct 2012 Location: Nelson, New Zealand Posts: 23,587	Originally Posted by RecoveringYuppy I haven't been paying enough attention to this recently, so let me ask some stupid questions. SN10 was a test of the first stage, correct? No, SN10 is not even remotely like any of the Starship stages, although it looks similar in shape to what the second stage is expected to look like. (The first stage is the superheavy booster, which will re-enter and land in much the same way as the Falcon 9 booster - tail first, with an "entry burn" and a "landing burn") SN10 is a test article, nothing more. It has much the same sort of role that the SpaceX "Grasshopper" had, i.e. proving the concept that autonomously hovering and landing a rocket at a precise location was feasible. It is purely for testing the concept of free-falling towards a landing in which the second stage will flip from near horizontal to vertical, as we saw it doing. The reason for this is that the intention is for the Starship second stage to re-enter from orbit in that nose-up belly first attitude, shedding off orbital velocity until comes down to terminal velocity. The reason for the two different methods is simple... the first stage only has to re-enter at speeds of around 6,000 kph - that is relatively low, so the engine bells and associated structure do not have to withstand a great amount of heating - the reason for the entry burn is to shed off speed to limit that heating. However, the second stage will be entering the earth's atmosphere at orbital velocity, about 28,000 kph - no entry burn, and the kicker is that convective heating isn't just proportional to velocity, its not even velocity squared, its velocity cubed!! - so double the entry speed from 6,000 to 12,000 kph, and the heating effect is eight times greater than at 6,000, double it again to 24,000 kph and the heating effect is 64 times greater than at 6,000 kph. Obviously, the thrust structure would not be able to withstand this; any attempt to re-enter tail first at those speed would result in the destruction of the vehicle. SpaceX had to come up with a different way to re-enter and land the second stage. This is the simplified version. There is also radiative heating that needs to be considered, and it is proportional to the eighth power of velocity.
	__________________ What is Woke? It is a term that means "awakened to the needs of others". It means to be well-informed, thoughtful, compassionate, humble and kind. Woke people are keen to make the world a better, fairer place for everyone, But, unfortunately, it has also become a pejorative used by racists, homophobes and misogynists on the political right, to describe people who possess a fully functional moral compass. Last edited by smartcooky; 5th March 2021 at 11:37 PM.

6th March 2021, 03:02 AM	#194
GlennB Loggerheaded, earth-vexing fustilarian Join Date: Sep 2006 Location: Wales Posts: 29,715	Originally Posted by smartcooky Care to elaborate on why you think that? SN8/9/10 have all experienced disaster at or just after landing. In addition, launch technology is well established, while soft landings are novel. Musk said, of this very technology, something like "There will be some holes in the ground along the way", and he wasn't talking about launches.
	__________________ "There ain't half been some clever bastards" - Ian Dury

6th March 2021, 03:28 AM	#195
smartcooky Penultimate Amazing Join Date: Oct 2012 Location: Nelson, New Zealand Posts: 23,587	Originally Posted by GlennB SN8/9/10 have all experienced disaster at or just after landing. In addition, launch technology is well established, while soft landings are novel. Musk said, of this very technology, something like "There will be some holes in the ground along the way", and he wasn't talking about launches. Ok, so you are specifically, talking only about these test article landings and not rocket landings in general.
	__________________ What is Woke? It is a term that means "awakened to the needs of others". It means to be well-informed, thoughtful, compassionate, humble and kind. Woke people are keen to make the world a better, fairer place for everyone, But, unfortunately, it has also become a pejorative used by racists, homophobes and misogynists on the political right, to describe people who possess a fully functional moral compass.