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1 hour ago, YNM said:

Starship is supposed to carry passengers anyway, they'll have a pressurized section...

Also, the standard version will have that flap and stuff. I honestly don't see how they're going to put a version that'll have a separable fairing - not that they can't do it but it makes little sense for them to ever put such version.

Like... what you're proposing is Dragon V1 trunk but with Starliner or Orion capsule. Why'd you want that ?

Crew Starship can't go to TLI without refuelling, and there's a large obstacle to crew rating it. It's a long pole.

Capsule on top of an expendable starship is the easiest and fastest way to put crew on it, and it keeps Orion and the Artemis archeture basically as-is without starting again from scratch. 

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14 minutes ago, JoeSchmuckatelli said:

...isn't the whole point of Starship to quit expending expensive rockets?

Yes, eventually.

Problem is getting starship to launch humans directly without LES require an insane number of testing.

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2 hours ago, Xd the great said:

Yes, eventually.

Problem is getting starship to launch humans directly without LES require an insane number of testing.

I get that - but if Elon is dedicatedly focused on Mars; don't you think he's got to at least land and return SShip from the Moon... at least once?

 

That would be an enormous coup; especially if he brings back regolith... and then relaunches the same ship within a year

Edited by JoeSchmuckatelli
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7 hours ago, YNM said:

Starship is supposed to carry passengers anyway, they'll have a pressurized section...

Yes -- "supposed to". They are a long way from doing that.

They do have a few parts of the puzzle. They now have a crewed space capsule, so they know how to do that. And they have a crew-rated rocket, so they know how to do that.

But they have still never crew-rated a propulsive landing system. With a crew-rated Starship they would need for the ship to be considered safe enough to be its own escape system from a failed booster. (That was always pretty iffy for Shuttle/SLS.) A bigger hurdle is that Starship has absolutely no backup for propulsive landing. That has to work or everybody on-board is dead. That's a big, big hurdle.

And of course there is the whole issue that so far the only "Starships" that have actually flown have been nothing but flying fuel tanks, and the only attempt so far to make a high speed propulsive landing failed to land safely.

Edited by mikegarrison
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8 hours ago, RCgothic said:

Crew Starship can't go to TLI without refuelling, and there's a large obstacle to crew rating it. It's a long pole.

Capsule on top of an expendable starship is the easiest and fastest way to put crew on it, and it keeps Orion and the Artemis archeture basically as-is without starting again from scratch. 

7 hours ago, Xd the great said:

Yes, eventually.

Problem is getting starship to launch humans directly without LES require an insane number of testing.

*looks at Shuttle where it's literally death if anything goes wrong while the SRBs are on, yet the first flight was immediately manned*

 

2 hours ago, mikegarrison said:

Yes -- "supposed to". They are a long way from doing that.

They do have a few parts of the puzzle. They now have a crewed space capsule, so they know how to do that. And they have a crew-rated rocket, so they know how to do that.

But they have still never crew-rated a propulsive landing system. With a crew-rated Starship they would need for the ship to be considered safe enough to be its own escape system from a failed booster. (That was always pretty iffy for Shuttle/SLS.) A bigger hurdle is that Starship has absolutely no backup for propulsive landing. That has to work or everybody on-board is dead. That's a big, big hurdle.

And of course there is the whole issue that so far the only "Starships" that have actually flown have been nothing but flying fuel tanks, and the only attempt so far to make a high speed propulsive landing failed to land safely.

Soyuz capsules have landing SRBs on them.

Also, they are now being contracted to investigate Starship as lunar HLS solution. That means that in a way they're providing for man-rating the thing, at least solely for in-orbit operations.

 

I'm not saying that man-rating this thing for launch and land on Earth will be easy. But we still have a decade in front of us. Let's not forget that F9 first flew in 2010, and they were only man-rated in 2020 after a whole decade of unmanned use. There's still time to 2030s. They'll just have to prove themselves with the unmanned version.

I'm not believing in Promised Elon Time folks. I only believe in Proven Elon Time, and we have that for F9/Dragon.

Edited by YNM
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3 minutes ago, YNM said:

Soyuz capsules have landing SRBs on them.

Several capsules intended for ground parachute landings use either airbags (Boeing Starliner) or SRBs (Soyuz, New Shepard, presumably the Chines Soyuz clone) to cushion the landing forces, but this is not the same thing as a propulsive landing. Those capsules will land survivably without that -- but there may be more force than desired upon impact.

8 minutes ago, YNM said:

Also, they are now being contracted to investigate Starship as lunar HLS solution.

There's no other choice on the moon.

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2 minutes ago, mikegarrison said:

Several capsules intended for ground parachute landings use either airbags (Boeing Starliner) or SRBs (Soyuz, New Shepard, presumably the Chines Soyuz clone) to cushion the landing forces, but this is not the same thing as a propulsive landing. Those capsules will land survivably without that -- but there may be more force than desired upon impact.

Yeah, but the idea is there, you can turn spine-crushing landing into less-than-spine-crushing-but-still-awful landing.

2 minutes ago, mikegarrison said:

There's no other choice on the moon.

And it'll help their progress.

Edited by YNM
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They might eventually be able to do single engine landings and do the flip manouver without the help of raptors (with aerodynamic surfaces + gas thrusters). Then 1 or even 2 engine failures wouldn't necessarily mean certain death if they can just use the remaining working engine to land.

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4 minutes ago, tseitsei89 said:

They might eventually be able to do single engine landings and do the flip manouver without the help of raptors (with aerodynamic surfaces + gas thrusters). Then 1 or even 2 engine failures wouldn't necessarily mean certain death if they can just use the remaining working engine to land.

Man-rating is one where even a 99% success record can look bad enough. They'll still have to prove themselves for years (I'd wager a whole decade) once the whole stack works unmanned-ly.

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1 minute ago, tseitsei89 said:

They might eventually be able to do single engine landings and do the flip manouver without the help of raptors (with aerodynamic surfaces + gas thrusters). Then 1 or even 2 engine failures wouldn't necessarily mean certain death if they can just use the remaining working engine to land.

Thing is, if you're using only one engine the flip has to occur at a higher altitude, which means the flight computer would have to detect engine failures before they happen and adjust its landing accordingly. 

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4 minutes ago, YNM said:

Man-rating is one where even a 99% success record can look bad enough. They'll still have to prove themselves for years (I'd wager a whole decade) once the whole stack works unmanned-ly.

Yes of course Raptors still need to be made extremely reliable and it will be a slow process. But if you look at Merlin in its current state, it really is super reliable nowadays.

3 minutes ago, RealKerbal3x said:

Thing is, if you're using only one engine the flip has to occur at a higher altitude, which means the flight computer would have to detect engine failures before they happen and adjust its landing accordingly. 

They can just flip higher up for manned flights anyway, engine failure or not. Yes it will need more propellant to slow down in the end but it will be safer. I mean they could plan the landing for 1 engine to begin with. Then if the planned engine doesn't ignite, just immediately try to ignite another one.

Edited by tseitsei89
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5 minutes ago, tseitsei89 said:

Yes of course Raptors still need to be made extremely reliable and it will be a slow process. But if you look at Merlin in its current state, it really is super reliable nowadays.

They can just flip higher up for manned flights anyway, engine failure or not. Yes it will need more propellant to slow down in the end but it will be safer.

Merlin has flown for 12 years (Falcon 1 also used them), and the design had started since at least 2002.

And the problem so far hasn't been with the engine itself, but the fuel management (fuel plumbing is extremely hard). Or at least we haven't tested the engine in-flight enough times until there is an issue that arose solely on the engine itself.

Like I said, it'll take them a whole decade since the first full-profile unmanned mission happened.

Edited by YNM
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Just now, YNM said:

Merlin has flown for 12 years (Falcon 1 also used them), and the design had started since at least 2002.

And the problem so far hasn't been with the engine itself, but the fuel management (fuel plumbing is extremely hard). Or at least we haven't tested the engine in-flight enough times until there is an issue that arose solely on the engine itself.

Yes that is exactly why I said it will be a slow process but not impossible. Falcon 9 is already quite reliable today.

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1 minute ago, tseitsei89 said:

Yes that is exactly why I said it will be a slow process but not impossible. Falcon 9 is already quite reliable today.

I'm not sure what the Promised Elon Time is rn but I'd wager we'll see them mid-2030s starting to launch customers from Earth and back.

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Just now, YNM said:

I'm not sure what the Promised Elon Time is rn but I'd wager we'll see them mid-2030s starting to launch customers from Earth and back.

Yeah obviously Elon-time is vastly different from reality.

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4 minutes ago, YNM said:

Merlin has flown for 12 years (Falcon 1 also used them), and the design had started since at least 2002.

And the problem so far hasn't been with the engine itself, but the fuel management (fuel plumbing is extremely hard). Or at least we haven't tested the engine in-flight enough times until there is an issue that arose solely on the engine itself.

The first mention of Raptor was in 2009. Back then it was a hydrolox upper-stage engine, and it only became a methalox engine around 2014. Since flight testing on Starhopper began in 2019, by 2030 that'll have been 11 years of flights. So if we're going off the Falcon 9 analogy, then 2030 seems reasonable for the first crewed launch.

Or maybe they'll have refined their development by then and we'll see Starship crew launches sooner. Who knows.

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12 minutes ago, tseitsei89 said:

Yes of course Raptors still need to be made extremely reliable and it will be a slow process. But if you look at Merlin in its current state, it really is super reliable nowadays.

The question is: would you put a crew in a F9 first stage? If not (which you shouldn’t), then the Starship crew-rating will take a lot more than Raptor certification.

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1 minute ago, RealKerbal3x said:

The first mention of Raptor was in 2009. Back then it was a hydrolox upper-stage engine, and it only became a methalox engine around 2014. Since flight testing on Starhopper began in 2019, by 2030 that'll have been 11 years of flights. So if we're going off the Falcon 9 analogy, then 2030 seems reasonable for the first crewed launch.

Or maybe they'll have refined their development by then and we'll see Starship crew launches sooner. Who knows.

Merlin was first tested in space from 2010. Merlin has only been propulsively landed back on Earth since 2015, and that's not the ones that goes to space. NASA hasn't accepted to use re-used boosters yet, although they're open to the idea. We'll see when a reused booster will be manifested for a crew launch on F9.

Plus, Starship hasn't even had the thermal protection system tested at all. 2030 is the fastest time IMO, but mid-2030s is much more likely.

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2 minutes ago, YNM said:

Merlin was first tested in space from 2010. Merlin has only been propulsively landed back on Earth since 2015, and that's not the ones that goes to space. NASA hasn't accepted to use re-used boosters yet, although they're open to the idea. We'll see when a reused booster will be manifested for a crew launch on F9.

Actually, they have. Crew-2 will reuse the first stage from Crew-1 and the Dragon spacecraft from Demo-2. NASA seems to now be fully leaning into utilising SpaceX's reusability.

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32 minutes ago, RealKerbal3x said:

Actually, they have. Crew-2 will reuse the first stage from Crew-1 and the Dragon spacecraft from Demo-2. NASA seems to now be fully leaning into utilising SpaceX's reusability.

Sadly not actually in the quoted article, the article just says that NASA "will allow reuse of Capsule and Booster starting with Crew-2" but there's nothing that says it's what is in the manifest of Crew-2.

Don't get me wrong, I myself hope that the propulsive landings of Dragon V2 will be used by NASA as well. It'd provide the precedent for Starship.

Edited by YNM
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3 hours ago, YNM said:

Man-rating is one where even a 99% success record can look bad enough. They'll still have to prove themselves for years (I'd wager a whole decade) once the whole stack works unmanned-ly.

If there were only a 99% chance of avoiding injury in a car trip, there would be 11,000,000 injury accidents in the US every day. 99% is completely unacceptable.

Edited by mikegarrison
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1 hour ago, mikegarrison said:

If there were only a 99% chance of avoiding injury in a car trip, there would be 11,000,000 injury accidents in the US every day. 99% is completely unacceptable.

Your idea is correct, but somehow I don't think that there are 1.1 billion car trips per day.  
regardless of the actual nulber, it sucks to be in the 1%

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9 minutes ago, linuxgurugamer said:

Your idea is correct, but somehow I don't think that there are 1.1 billion car trips per day. 

According to Google, there are (or rather were in 2017) 1.1 billion car trips per day in the US.

I believe that this includes, for example, driving to Starbucks, then to the office, working there, then to a pizza place, and then home as four trips, even though conceptually it could be argued they are two trips or even one round trip.

(It's more usual to compare accident rates per passenger-mile or passenger-km rather than trips.)

Edited by mikegarrison
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