Starship Launch!

[martin-w 3,258]

17 minutes ago, DaviiB said:

shed a bunch of heat-shield tiles on the way up.

 

Yes, I heard that too. There is a thermal blanket that's left behind when they drop off that can take, something like, 1500 degrees, so one or two dropping off isn't necessarily catastrophic. Stainless steel as well, which is more heat resistant than the aluminum shuttle was. 

[HiFlyer 9,374]

On 11/18/2023 at 12:30 PM, charliearon said:

Rocky Jones Space Ranger

Just looked up that reference....

*Snort/Giggle! 🙃

Winky..... Really?

[martin-w 3,258]

Nice 360 view of launch.

 

 

[DaviiB 104]

On 11/21/2023 at 11:08 AM, martin-w said:

 

Yes, I heard that too. There is a thermal blanket that's left behind when they drop off that can take, something like, 1500 degrees, so one or two dropping off isn't necessarily catastrophic. Stainless steel as well, which is more heat resistant than the aluminum shuttle was. 

Again, I don't envy the guy who's job it is to figure out if the metal under that blanket was compromised on reentry. These are meant to be rapidly-reusable. 

Surviving reentry is one thing. Surviving twice is a whole other problem.

DB

[martin-w 3,258]

I think its a pretty straightforward task. They use xrays and all manner of techniques these days. And I recall that this particular stainless steel gets stronger with heating.

I don't think rapid reusability means the same booster and Starship each flight. There will be a fleet of them. When one lands the next rolls out. In fact that's the case now, there are several prototypes waiting in the wings. 

Surviving twice has been surpassed by SpaceX of course, with a recent booster achieving its 9th flight. Not as rapidly reused as is hoped for Starship, but relatively quick all the same. Dragon capsules are reused too of course... up to 15 times.

Edited November 23, 2023 by martin-w

[DaviiB 104]

12 hours ago, martin-w said:

I think its a pretty straightforward task. They use xrays and all manner of techniques these days. And I recall that this particular stainless steel gets stronger with heating.

And they'll need to be willing to bet a whole lot of money (and payloads) on that. Again, a task for people much smarter than me.

 

12 hours ago, martin-w said:

I don't think rapid reusability means the same booster and Starship each flight. There will be a fleet of them. When one lands the next rolls out. In fact that's the case now, there are several prototypes waiting in the wings. 

It's definitely referring to reusability of the same vehicle. Otherwise it would be "rapid launchability".....and it's easy enough to do that as long as you don't destroy the launch site every time.....just roll the cranes as soon as the last one clears the tower.

 

13 hours ago, martin-w said:

Surviving twice has been surpassed by SpaceX of course, with a recent booster achieving its 9th flight. Not as rapidly reused as is hoped for Starship, but relatively quick all the same. Dragon capsules are reused too of course... up to 15 times.

That is true, but the boosters don't have to re-enter from orbit. The Dragon capsules are a better analogue, but still, they're protected on the way up. Starship doesn't have that benefit.

All the same, I'm excited for them to figure it all out. Who could see all this coming 10 years ago? (except SpaceX, of course).

DB

[martin-w 3,258]

10 hours ago, DaviiB said:

And they'll need to be willing to bet a whole lot of money (and payloads) on that. Again, a task for people much smarter than me.

 

Musk has said that Starship can lose quite a few tiles without issue. I'm sure that's based on calculations. The true test is when it does encounter the atmosphere, of course, hopefully next flight.

The shuttle used to lose a few tiles, as I'm sure you know, STS 27 suffered loss of tiles and survived reentry, as long as they weren't lost in critical locations of course, and that was an aluminum spaceship, we saw what happened when they were in a critical place. Much more serious issue than for Starship. The Shuttle thermal protection was a different system of course, not such sophisticated tiles, square not hexagonal and gaps filled with a heat resistant reinforced caulking. 

Starship is stainless steel with a thermal blanket, as I mentioned, and also with cryogenic fuel beneath the tiles, in addition, the tiles are hexagonal so that hot plasma doesn't have a straight path. In theory, the stainless steel could glow hot and not fail. But yes, as I say, the true test will be next flight hopefully. Some are dubious about the dowel pins that are used to secure the tiles, so it will be interesting to see how well the system works. 

 

10 hours ago, DaviiB said:

It's definitely referring to reusability of the same vehicle. Otherwise it would be "rapid launchability".....and it's easy enough to do that as long as you don't destroy the launch site every time.....just roll the cranes as soon as the last one clears the tower.

 

Yep. Well clearly they aren't going to keep using the same vehicle each flight, that would be silly. They wouldn't use one vehicle only and leave all of the others standing around unused. I envisage the Starship that has landed being removed from the launchpad and pretty much within hours or days a new Starship takes its place. And of course, if the Starship that has just landed doesn't fly again for a week, fortnight, month, or several months... it's still very rapid reusability. Artemis currently flies once every two years. Falcon 9 launched every two weeks in 2022, but that wasn't the same launch vehicle every time. Musk will have a fleet of Starships for a reason. Just as there's currently numerous porotypes in the wings. They are currently about to start work on a second launch platform at Starbase, so looks like we will have two prototypes ready to go one after the other.

 

10 hours ago, DaviiB said:

The Dragon capsules are a better analogue, but still, they're protected on the way up

 

Dragon isn't protected on the way up. It's at the top of the booster, mostly uncovered. The heat shield is covered on the way up. But that's a different system, not thermal tiles. Its a Phenolic Impregnated Carbon Ablator. Vibration isn't an issue on the way up as its covered (as you imply) and not tiles that can fall off. reentry isn't the same issue as tiles for the same reason, so you are correct there. 

 

10 hours ago, DaviiB said:

All the same, I'm excited for them to figure it all out. Who could see all this coming 10 years ago? (except SpaceX, of course).

 

Exactly, it will be a phenomenal achievemnt. 👍