Wiki Super Heavy/Starship - General Development Discussion

[ecarfan]

New NSF video shows the hot staging ring being removed and workers up there on a lift doing…something. The ring appears to be relatively easy to remove. I wonder if, in the future, once the stage sep technique is perfected, if the hot staging ring will be welded in place to negate the need for clamps and save a bit of weight?

Also, S26 was cryo tested on its suborbital stand. You can even see a frost ring on the header tank in the nose.

S30 and S31 in the Megabay are looking good.

 

[mongo]

New NSF video shows the hot staging ring being removed and workers up there on a lift doing…something. The ring appears to be relatively easy to remove. I wonder if, in the future, once the stage sep technique is perfected, if the hot staging ring will be welded in place to negate the need for clamps and save a bit of weight?

Also, S26 was cryo tested on its suborbital stand. You can even see a frost ring on the header tank in the nose.

S30 and S31 in the Megabay are looking good.

View attachment 981505

Ring being clamped allows access to the grid fin stuff.

 

[JB47394]

Ring being clamped allows access to the grid fin stuff.

We talked about this before, and I think the biggest reason they won't weld it on is because it's going to be taking a lot of point blank punishment from Raptors. Unless they make the thing beefy, it's going to have to be repaired or replaced. Beefing it up doesn't make any sense given that they want to keep the weight down, and replacing it is probably more reliable than repairing it. So I expect it to be replaced. Bolt it on and put a hatch for employee access.

What we don't know is whether they'll go with this ring approach in the long term. I think this was a quick knockoff that allowed them to try hot staging without a huge investment. They've already got a tower, a manufacturing base, and certain flight dynamics. They aren't going to get too inventive with the thing, especially on the first flight.

I continue to hope that they'll go with the Soviet-style hot staging system, clearly visible on the N1 rocket. It's manufactured a different way, but it offers great strength with low mass, it's simple to build, and they can get as much separation as they want between the stages. They probably wouldn't bother with it for Boca Chica because of the launch tower restrictions, but when they move to the Cape, I think they won't be as constrained. We'll have to wait and see what they learn from the flight tests.

 

[AudubonB]

Almost on topic: how far in advance can we learn of launch schedules? I would love to be able to take Gus to Boca Chica around April 8th…for a launch and the solar eclipse.

 

[winfield100]

Almost on topic: how far in advance can we learn of launch schedules? I would love to be able to take Gus to Boca Chica around April 8th…for a launch and the solar eclipse.

View attachment 982121

@AudubonB
keep an eye on (like daily)

nextspaceflight.com

however looks like "officially" something Boca Chica this month, then over at Cape Canaveral subsequently, so ? 2 ? trips? (nice scope)
(i find it "improbable" launches will all move to the cape, maybe do a "launch hop" to the cape from Boca Chica, "point to point, then launch to orbit & beyond, eh)

Rocket Launch Schedule

Next Spaceflight's rocket launch schedule keeps you up to date with rocket launches both past and present.

nextspaceflight.com

 

[JB47394]

how far in advance can we learn of launch schedules?

About a week, possibly two, and that just means that SpaceX is going to attempt a launch of their experimental rocket. You should entirely focus on experiencing the eclipse, visiting Boca Chica to see the amazing things going on there, visiting the beach (it's walking distance from the launch tower), and hope that your timing works out for a Starship launch. The odds are not in your favor for the launch, and you should also expect things to be kinda crazy down there for the eclipse. I wonder if there are still any hotel rooms to be had.

To end on a bit of an up note, 33 years ago I flew down to Florida to see Discovery's launch with the Hubble Space Telescope. She had a hardware failure on an APU so she didn't fly while I was down there. But, as consolation, I was able to take a bus tour that drove right past Discovery on the pad, complete with Hubble in the cargo bay. I would have missed out on being that close to a flight-ready Shuttle (and Hubble) if she had flown on time.

I hope you and your son have a great trip.

 

[ecarfan]

S29 was moved back to the Rocket Garden after completing testing at Masseys, B11 was moved to Masseys for testing, and there are indications that SpaceX is preparing to re-stack S27 at the launch site. Plus, a coyote wandered in front of one of the NSF cameras across the road from the launch site.

 

[TarmacSurfer]

Booked my place in TX a few months ago for the eclipse - at that time most hotels still hadn’t caught on that there was going to be a high-demand event then. Now it’s either impossible to find space at all or the cost is so ridiculous as to be prohibitive (just for fun I went online a few weeks ago and rooms that normally would be around $150 were listed north of $700 a night for that week).

It’d be serendipitous to be able to catch a Starship launch at the same time for sure! At this rate I’m wondering if they’ll even have a launch permit for attempt #2 by then though…

 

[scaesare]

We talked about this before, and I think the biggest reason they won't weld it on is because it's going to be taking a lot of point blank punishment from Raptors. Unless they make the thing beefy, it's going to have to be repaired or replaced. Beefing it up doesn't make any sense given that they want to keep the weight down, and replacing it is probably more reliable than repairing it. So I expect it to be replaced. Bolt it on and put a hatch for employee access.

What we don't know is whether they'll go with this ring approach in the long term. I think this was a quick knockoff that allowed them to try hot staging without a huge investment. They've already got a tower, a manufacturing base, and certain flight dynamics. They aren't going to get too inventive with the thing, especially on the first flight.

I continue to hope that they'll go with the Soviet-style hot staging system, clearly visible on the N1 rocket. It's manufactured a different way, but it offers great strength with low mass, it's simple to build, and they can get as much separation as they want between the stages. They probably wouldn't bother with it for Boca Chica because of the launch tower restrictions, but when they move to the Cape, I think they won't be as constrained. We'll have to wait and see what they learn from the flight tests.

Do you see a potential downside to the hot-stage ring design SpaceX currently has? Or is it just a matter of the Soviet one looks easier/cheaper?

 

[JB47394]

Do you see a potential downside to the hot-stage ring design SpaceX currently has? Or is it just a matter of the Soviet one looks easier/cheaper?

It's the difference between designing something for the task and just fitting something in that will get the job done. SpaceX is using a kludge.

Apart from it being more difficult to build, I'm assuming that the SpaceX design is heavier. I'm also assuming that the small size and its associated small vent area means that the pressures and temperatures inside the interstage are going to be increased, which should reduce the lifespan of the ring.

None of that is important at this point, but those are the sorts of things that cause me to expect them to redesign it if hot staging works out.

One reason that occurs to me for SpaceX not going with the spiderweb interstage is that it wouldn't look cool. Elon's eccentricity may mean that wouldn't want his beautiful silver rocket getting too cluttered. He might push for something that better fits the rocket's aesthetics.

 

[mongo]

Do you see a potential downside to the hot-stage ring design SpaceX currently has? Or is it just a matter of the Soviet one looks easier/cheaper?

I loke Starship's hot ring.
SpaceX is dealing with double the mass and more thrust compared to N1. Their ring uses the design of the rest of the ship, no reason to make a separate tube structure. Plus, it needs to keep rocket reusable, versus direct impingement on the booster propellant dome.

 

[winfield100]

Booked my place in TX a few months ago for the eclipse - at that time most hotels still hadn’t caught on that there was going to be a high-demand event then. Now it’s either impossible to find space at all or the cost is so ridiculous as to be prohibitive (just for fun I went online a few weeks ago and rooms that normally would be around $150 were listed north of $700 a night for that week).

It’d be serendipitous to be able to catch a Starship launch at the same time for sure! At this rate I’m wondering if they’ll even have a launch permit for attempt #2 by then though…

CampMode?

 

[ecarfan]

One reason that occurs to me for SpaceX not going with the spiderweb interstage is that it wouldn't look cool. Elon's eccentricity may mean that wouldn't want his beautiful silver rocket getting too cluttered. He might push for something that better fits the rocket's aesthetics.

Maybe. But the Starship staging ring needs to be more durable than any Russian design since it is planned to be re-used many times as @mongo pointed out.

It is going to be fascinating to see how all aspects of Starship evolve over the next several years of flight testing. There will be lots of changes.

 

[ecarfan]

NSF livestream shows that S25 has been re-stacked. Again. It seems to have taken about an hour.

 

[JB47394]

I see they're not swinging Starship close to the booster until they clear the grid fins now, and they're continuing the lift as they get past the fins. It all looks much smoother. The mating itself continues to be hesitant, but I didn't see any significant rocking of the stack when they finally connected. The NSF guys commented on the thump, but I think that was just a little shift, so SpaceX had it pretty close.

Notice that the hot staging ring now has external stringers, so it has been reinforced. It looks like they may be at three points, uniformly spaced around the circumference.

An update video pointed out that there is a Marine Safety Information Bulletin for the launch site, and those apparently go out when SpaceX is doing their more energetic testing. So we may soon see spin primes, static fires or even a wet dress rehearsal.

 

[ICUDoc]

their more energetic testing

Best euphemism I've heard in ages!

 

[scaesare]

I see they're not swinging Starship close to the booster until they clear the grid fins now, and they're continuing the lift as they get past the fins. It all looks much smoother. The mating itself continues to be hesitant, but I didn't see any significant rocking of the stack when they finally connected. The NSF guys commented on the thump, but I think that was just a little shift, so SpaceX had it pretty close.

Notice that the hot staging ring now has external stringers, so it has been reinforced. It looks like they may be at three points, uniformly spaced around the circumference.

An update video pointed out that there is a Marine Safety Information Bulletin for the launch site, and those apparently go out when SpaceX is doing their more energetic testing. So we may soon see spin primes, static fires or even a wet dress rehearsal.

Cool...

So in the crop below, I assume the section pointed to by the red arrow are the reinforcements you are talking about? Those external stringers do look new....

Also, it looks like there's a "tab" that fits in the slot on the bottom of the ship's skirt (each circled in blue). While I can see a couple more slots in the bottom of the ship, I don't see any more corresponding tabs on the hot stage ring:

 

[mongo]

Cool...

So in the crop below, I assume the section pointed to by the red arrow are the reinforcements you are talking about? Those external stringers do look new....

Also, it looks like there's a "tab" that fits in the slot on the bottom of the ship's skirt (each circled in blue). While I can see a couple more slots in the bottom of the ship, I don't see any more corresponding tabs on the hot stage ring:

View attachment 982822

There are three clamps (blue circle).

 

[scaesare]

There are three clamps (blue circle).

So that's actually the clamping mechanism... ok thanks.

I fid it interesting there appear to be additional clamping "slots" in the ship lining up with reinforced sections of the ring, but no actual clamp:

 

[mongo]

So that's actually the clamping mechanism... ok thanks.

I fid it interesting there appear to be additional clamping "slots" in the ship lining up with reinforced sections of the ring, but no actual clamp:

View attachment 982823

Yeah, they have reinforcement features every 60 degrees, but only three have clamps. Theoretically, the mating surface is in compression the entire time.