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26 minutes ago, RyanRising said:

Splitting the skirt would require a lot of reinforcement, but if there’s anything to be learned from all the shots people have been giving the landing legs, something’s probably got to give. Splitting the skirt in this way doesn’t necessitate a heatshield seam and provides an alternative path (around the covers) for the load to take.

The current landing legs fold out onto the same points that are used to hold onto Starship while it is sitting on the pad. Presumably if you split the heat shield like this you would make the stowed-position feet themselves the hold-down points.

26 minutes ago, RyanRising said:

Would it be feasible to have six of these, with two coming out from under the rear flaps and the appropriate modifications made to those flaps’ and aerocovers’ shapes? Or does that mean you’ve got a severe gap in the heatshield again? Maybe it would be desirable to have them clocked so that one faces directly windward and leeward?

I don't know if they could manage six or not. Four seems like plenty.

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3 hours ago, sevenperforce said:

Okay, so this is definitely my favorite Starship leg concept yet.

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I hate to be a downer, but that looks absolutely massive! I suspect the final design will be much closer to aircraft landing gear with minimal actuators (amount in total, as well as size of) and a lot more straight pieces of metal with control horns on them.  I also suspect the auto-levelling feature will involve a ratcheting design as opposed to active hydraulic control.

Edited to add: No, I do sound like a downer...seriously man, I love that you toss your ideas out there!

Edited by Meecrob
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2 minutes ago, Meecrob said:

I hate to be a downer, but that looks absolutely massive! I suspect the final design will be much closer to aircraft landing gear with minimal actuators (amount in total, as well as size of) and a lot more straight pieces of metal with control horns on them. 

Oh, it is clearly way, way too large. No question about that. I was just trying to design it in KSP which is inherently difficult since I don't have Tweakscale installed.

3 minutes ago, Meecrob said:

I also suspect the auto-levelling feature will involve a ratcheting design as opposed to active hydraulic control.

Using active hydraulic control for auto-leveling allows shock absorbers to also be the auto-levelers. The best part is no part.

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3 minutes ago, sevenperforce said:

I don't know if they could manage six or not. Four seems like plenty.

With four legs, if there's a problem with one of them you most likely tip. It's a little more avoidable with active levelling, since you can try to tip it over onto the three remaining, but still less redundant. With six legs there are scenarios in which one just fails to deploy entirely yet you'd be fine on landing, while pointing straight up. It also allows for sixfold or trifold symmetry again, allowing the same three vacuum raptors they've planned for the normal Starship (yeah, not great for pulling the ship off the top in case of an abort, but that's not exactly a confidence-inspiring abort mode anyway), and probably six vacuum raptors for the upgraded refuelling Starship that may or may not come to pass.

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14 minutes ago, RyanRising said:

With four legs, if there's a problem with one of them you most likely tip. It's a little more avoidable with active levelling, since you can try to tip it over onto the three remaining, but still less redundant. With six legs there are scenarios in which one just fails to deploy entirely yet you'd be fine on landing, while pointing straight up. It also allows for sixfold or trifold symmetry again, allowing the same three vacuum raptors they've planned for the normal Starship (yeah, not great for pulling the ship off the top in case of an abort, but that's not exactly a confidence-inspiring abort mode anyway), and probably six vacuum raptors for the upgraded refuelling Starship that may or may not come to pass.

There might be enough space for six.

One thing is that with this wide stance, though, you'd have to have a complete failure to not have SOME kind of support on that end.

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So I actually went back to the drawing board and rebuilt this in KSP with the proper dimensions (using 3.5 meter parts instead of 5 meter parts) and....

......I cannot believe how well it works.

Like, it works REALLY well. Amazing shock absorption. I put a single Vector underneath and was able to do a 150 meter hop perfectly the first time with no problem whatsoever.

perfect-legs.png

 

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Did anyone figure out how big those bulges on the renders are, e.g. with pixel counting? Its hard to imagine both pistons and the feet themself fitting in there, under a cover of heatshield tiles. But with the huge scale of starship it might be enough...

Actualy, why couldnt they mount such a thin mechanism on the inside of the skirt, thus needing no extra shielding? Seems more simple and i cant imagine that the space is that constrained they have to go on the outside.

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12 minutes ago, Elthy said:

Actualy, why couldnt they mount such a thin mechanism on the inside of the skirt, thus needing no extra shielding? Seems more simple and i cant imagine that the space is that constrained they have to go on the outside.

Yeah, there could be perforations under the bulges, it need not be an entire break in the skirt.

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6 minutes ago, Elthy said:

Did anyone figure out how big those bulges on the renders are, e.g. with pixel counting? Its hard to imagine both pistons and the feet themself fitting in there, under a cover of heatshield tiles. But with the huge scale of starship it might be enough...

Actualy, why couldnt they mount such a thin mechanism on the inside of the skirt, thus needing no extra shielding? Seems more simple and i cant imagine that the space is that constrained they have to go on the outside.

It's a surprisingly compact solution. Like I said, I was able to do it in actual KSP without any clipping.

But trying to move them inside the skirt is actually really tough. There are enough internal parts to make it a challenging fit. And you lose more of the wide stance than you would think.

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1 hour ago, sevenperforce said:

Oh, it is clearly way, way too large. No question about that. I was just trying to design it in KSP which is inherently difficult since I don't have Tweakscale installed.

Using active hydraulic control for auto-leveling allows shock absorbers to also be the auto-levelers. The best part is no part.

I'm thinking along the lines of combining all those things actually are two parts, not zero parts.  A hydraulic actuator with shock absorbing capability is inherently heavier and not as optimal. My thought is make shock absorbers just do shock absorption, and have a mechanical gear extend mechanism, simply because weight is clearly an objective and we have been doing this for like 100 years. There is a reason planes do not have triple hydraulic actuators as opposed to two fixed posts and one hydraulic actuator. I hate to relate it to planes though. I know its a different regime, but I feel that weight is the exact reason the gear sucks so much on starship right now. Actually I think I just outed myself there, I think the gear sucks! haha. With reference to my idea of ratcheting, what say you of that...the logic would be basically weight dependant and "amount of legs touched down" dependant. Set up a sawtooth array of metal and have an electromagnet be the interference to stop travel. The actual gear though....I spent my brainpower thinking of this part...just like likes on this forum, I spread myself too thin haha

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21 hours ago, sevenperforce said:

It was the kaboom that launched it in the air, not the 3 bar of ullage pressure. The kaboom was probably 100 bar or more.

I watched Scott Manley's analysis after posting...and he said it was the fuel pressure. IDK.

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I hope we see BN1 fully stacked over the next few weeks. I suppose they'll do that after rolling out SN11, and they'll do that before stacking SN15's nose and fins.

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9 minutes ago, CatastrophicFailure said:

There’s that hindsight thing again... :P

 

Any confirmation of intentionally allowing it to RUD?

Oh, and, I couldn't resist. Hope someone picks up on it and retweets it....

 

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6 minutes ago, StrandedonEarth said:

Any confirmation of intentionally allowing it to RUD?

I’m more interested in how well the thermal tiles survived that bump, personally. If they held on, that’s a really good sign that the mounting system is maturing. 

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It seems like SpaceX should make a big vertical test stand where they can do full-length firings of Starships and Super Heavies just to test multiple Raptors under various combinations and situations. Or maybe they think it's cheaper to just test them in flight.

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1 hour ago, CatastrophicFailure said:

There’s that hindsight thing again... :P

 

I had no idea they could land the thing on two Raptors. Either they’ve gotten the Raptors to throttle lower already, or the ship even in this state is a lot heavier than I thought it was. >160t, for two 200t-f raptors at 40%? Yikes. No wonder they’re trying to make the thing even more of a balloon tank than it already is it that’s the case.

 

EDIT: or does that mean they’ll attempt a suicide burn?

Edited by RyanRising
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1 hour ago, tater said:

No way they wanted a RUD. Zero probability.

51006496043_88be1278fa_h.jpg

 

51007202541_e7a94213af_k.jpg

 

Not a particularly great render TBH. It falls into the uncanny valley of not being quite true to the real SN10 and having lots of effort put into it.

The sky is clearly a stock image, the creator went WAY overboard on the engine flares in the first pic, and the rest of the vehicle just doesn’t look right.

:wink:

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2 hours ago, Brotoro said:

It seems like SpaceX should make a big vertical test stand where they can do full-length firings of Starships and Super Heavies just to test multiple Raptors under various combinations and situations. Or maybe they think it's cheaper to just test them in flight.

The problem with a full stage static test is it doesn't necessarily give a lot more experience than a single engine lengthy test fire.  It doesn't load and stress the vehicle as much as an actual flight, and is much more expensive than a single engine lengthy test fire.  Being held on the pad with all engines firing only happens for at most a few seconds for a live flight.

These are about the equivalent of a cross between boilerplate tests and the Saturn I test series, which started out with just the first stage and dummy upper stages.  Saturn I had a lot of changes with respect to previous launch vehicles (much larger rocket, upgraded engines, 8 engines with cross-feed piping to 9 tanks and engine-out adaptable flight) and started off after static tests with only a live first stage and dummy upper stages.

With Starship, SpaceX is following an equivalent test program as adapted to what is being developed new for it as well as its critical performance needs.  The SN are not true flight articles but test flight articles made in an equivalent manner but not up to the standards required of even uncrewed launch vehicles.  They can do this because the tests are focused on short flight durations, low altitude flight, flight transitions, and landings without any payload.

When SpaceX gets to producing closer to the actual true flight articles, then full stage static tests are likely prior to test flights.

Edited by Jacke
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1 hour ago, JcoolTheShipbuilder said:

Just wondering, when will sn11 launch? About a month?

It moves to the pad Monday. Cryo proof, then statice fire...

Launch in 1-2 weeks?

SN11 will do the 3 engine flip, and 2 engine landing.

 

Gotta wonder what is up with SN15. The lack of a nose tip, for example.

 

Edited by tater
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7 hours ago, sevenperforce said:

It's a surprisingly compact solution. Like I said, I was able to do it in actual KSP without any clipping.

But trying to move them inside the skirt is actually really tough. There are enough internal parts to make it a challenging fit. And you lose more of the wide stance than you would think.

Bulges will however be an problem here, note you can reduce the bottom cargo holds a lot, I see them as a bit pointless however for moonship they could be nice for eva stuff if you could lower them down for access from ground. 
Another thing is to bring the pairs between engines closer together. One final tricks might be to have the tip point a bit downward and have this work as the initial dampening. 
Only issue I see with this design is dampening and having the tips make contact first might help here, the cylinder doing the tilting is very long granted it will not be an cylinder all the way 

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