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10 minutes ago, tater said:

Can't believe we get to see this thing fly again so soon.

I dunno how many pieces it's gonna be in when it does, but I'm still leaning towards 'more than one'. If they can pull a flawless flight with a Starship that was dropped I'll be impressed.

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26 minutes ago, tater said:

Ep4KvlOXcAQc7Bw?format=jpg&name=4096x409

New desktop pic there. The vehicles and stuff around it look like toys. Honestly it looks like part of someone’s model railroad setup. And I know, but forget who, someone here is an avid railroad buff that needs to add this to their layout. 

17 minutes ago, cubinator said:

I dunno how many pieces it's gonna be in when it does, but I'm still leaning towards 'more than one'. If they can pull a flawless flight with a Starship that was dropped I'll be impressed.

It didn’t drop, it just got a little tipsy

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1 hour ago, sevenperforce said:

That crane is such an absolute monster

And they’re going to have a bigger one. :o

12 minutes ago, cubinator said:

I dunno how many pieces it's gonna be in when it does, but I'm still leaning towards 'more than one'. If they can pull a flawless flight with a Starship that was dropped I'll be impressed.

That stainless is some pretty tough stuff, it looks like the upper fin and nose section absorbed most of the load, and of course, it was empty. Now, from what I understand, it was the jacks underneath that failed, and from the vid it looked to go over relatively slowly, more like Drunk Uncle Frank slowly crumpling to the floor whilst clinging to the sink rather than simply faceplanting. 

Also, it’s worth noting, this actually did fall, fully loaded, and could’ve been used again...

Spoiler

 

:D

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6 hours ago, StrandedonEarth said:

New desktop pic there. The vehicles and stuff around it look like toys. Honestly it looks like part of someone’s model railroad setup. And I know, but forget who, someone here is an avid railroad buff that needs to add this to their layout. 

It didn’t drop, it just got a little tipsy

That was my first thought too. "Hey that's cool, somebody made a Starship diorama. Nice painting on the background and attention to detail on the pickups and... oh.

waitaminute

thats-not-a-diorama-is-it

Wow.

As for the dropped rocket - probably for the best that Starship uses methane rather than ethanol as a fuel. You could make some serious punch with a Starship load of grain spirit - enough to get even the biggest rocket tipsy.

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More notional landing leg designs from ongoing discussions over at NSF...

index.php?action=dlattach;topic=52460.0;

Pneumatic pistons that run through the skirt, with embedded fold-out feet. The existing landing feet deploy from inside the skirt and brace against the fold-out feet to provide redundancy crush cores. The pistons provide the shock-absorbing and auto-leveling elements at touchdown. You can retract and replace individual landing feet crush cores (if necessary) while the vehicle remains standing.

17 minutes ago, Scotius said:

Yo, dawg! I heard you like cranes:

[snip]

I can only comment... Mind. Blowing :)

Good grief.

"I am become ubercrane, the lifter of worlds."

32 minutes ago, tater said:

 

Spoiler

Ep7kevMXUAE0huF?format=jpg&name=4096x409

 

There's something so cool about seeing the heat shield "growing" on the side of Starship like moss.

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2 minutes ago, sevenperforce said:

More notional landing leg designs from ongoing discussions over at NSF...

That's an interesting idea, I like it better than the others assuming the slots in the skirt to allow the legs to penetrate don't weaken it (since it has to support the loaded mass then interface to SH).

2 minutes ago, RealKerbal3x said:

The problem I see with this particular design is that it doesn't have a much wider stance than the current legs. Otherwise though, nice.

Yeah, for Earth use I think those are fine, but for the Moon or Mars? I think it really needs a grossly wider stance than they have right now (and ideally higher off the surface).

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IMO these landing leg designs you keep showing us are pretty clearly being designed by people who have no idea how to design landing gear. I mean, I'm not a landing gear designer myself, but they all look fragile and overly supplied with independent failure modes.

Edited by mikegarrison
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1 minute ago, tater said:

That's an interesting idea, I like it better than the others assuming the slots in the skirt to allow the legs to penetrate don't weaken it (since it has to support the loaded mass then interface to SH).

They also have to run through the heat shield on the belly side. Might cause some difficulties.

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1 minute ago, RealKerbal3x said:

The problem I see with this particular design is that it doesn't have a much wider stance than the current legs. Otherwise though, nice.

After some reflection, I don't actually think Starship needs a dramatically wider stance. Elon has said he wants a wider stance, yes, but there are diminishing returns. Starship is not going to be able to successfully land if it is coming in at an angle greater than what a single engine and the landing thrusters can compensate for. The current legs are actually quite useful because they correct off-axis loading when Starship comes in at a tilt:

index.php?action=dlattach;topic=52460.0;

Obviously the tilt shown is exaggerated, but you can see that as long as the angle of descent is less than the angle of the legs, they act correctively.

A little wider footprint would be nice, but auto-leveling is going to be more important. In my opinion.

3 minutes ago, tater said:

That's an interesting idea, I like it better than the others assuming the slots in the skirt to allow the legs to penetrate don't weaken it (since it has to support the loaded mass then interface to SH).

Yeah, I'm thinking the slots in the skirt would need to be reinforced to the skirt and also allow it to transmit force directly to the tank underside...probably using the same mounting approach as the vacuum Raptors.

2 minutes ago, mikegarrison said:

IMO these landing leg designs you keep showing us are pretty clearly being designed by people who have no idea how to design landing gear. I mean, I'm not a landing gear designer myself, but they all look fragile, and overly supplied with independent failure modes.

They're my designs, so yes, you're right. I have no experience designing landing gear.

That said, the current legs look EXTREMELY fragile.

One advantage of having multi-element legs like this last design is that it provides redundancy. Ordinarily they work together, but if one fails to deploy then the other can compensate...perhaps with some damage, but it's better than a failed landing.

2 minutes ago, sh1pman said:

They also have to run through the heat shield on the belly side. Might cause some difficulties.

I'm assuming the heat shield will wrap around the leg fairings as shown:

shield.png

The elements don't have to extend through the shield; all the extension is through the base.

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3 minutes ago, mikegarrison said:

IMO these landing leg designs you keep showing us are pretty clearly being designed by people who have no idea how to design landing gear. I mean, I'm not a landing gear designer myself, but they all look fragile and overly supplied with independent failure modes.

The current SS legs simply swing outwards and lock, but they have said that a requirement will be self-leveling. At some point the complexity of them will have to increase substantially for self-leveling (not that I have any idea how they will accomplish that).

I honestly think that for lunar starship they could make something more complex, and deploy them in orbit (then if there are issues they can address them there, vs dropping the legs moments before landing).

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I tend to doubt they are going to find a way to get good, reliable landing gear inside the engine skirt. They still have the basic problem that when they locked in the design of the engines and the skirt they still had the landing gear on the outside. I suspect that they are probably ultimately going to have to find some way to move the landing gear back outside again.

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Just now, mikegarrison said:

I tend to doubt they are going to find a way to get good, reliable landing gear inside the engine skirt. They still have the basic problem that when they locked in the design of the engines and the skirt they still had the landing gear on the outside. I suspect that they are probably ultimately going to have to find some way to move the landing gear back outside again.

Yeah. I tend to forget looking at the current SS on the pad that their renders show that the belly side has that flat section that covers both legs on that side in a sort of extra skirt, too. The leeward side legs could be... whatever is needed.

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Just now, sevenperforce said:

One advantage of having multi-element legs like this last design is that it provides redundancy. Ordinarily they work together, but if one fails to deploy then the other can compensate...perhaps with some damage, but it's better than a failed landing.

Looks more like multiple ways to fail. I'm not trying harsh your mellow or anything, but you've got to keep in mind the engineering rule of making something just as complicated as it needs to be, but no more so.

4 minutes ago, tater said:

I honestly think that for lunar starship they could make something more complex, and deploy them in orbit (then if there are issues they can address them there, vs dropping the legs moments before landing).

Yes, absolutely. The only reason to extend the legs right before landing is to prevent them from having aerodynamic effects, and there is no need for that on the moon.

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10 minutes ago, tater said:

The current SS legs simply swing outwards and lock, but they have said that a requirement will be self-leveling. At some point the complexity of them will have to increase substantially for self-leveling (not that I have any idea how they will accomplish that).

The simplest thing would be to have a single mechanism provide deployment, shock absorption, and self-leveling all in one. That's basically what notional landing leg in current SpaceX renders shows:

giphy.gif

Pneumatic or hydraulic pistons to deploy, shock-absorb, and auto-level. This just doesn't provide QUITE as much footprint as Elon, would like, though. Using this same design and simply angling it through the skirt would do the trick:

Spoiler

straight-drop-simpler.png

 

34 minutes ago, tater said:

I honestly think that for lunar starship they could make something more complex, and deploy them in orbit (then if there are issues they can address them there, vs dropping the legs moments before landing).

Yeah, they could. No atmosphere and no heat shield. At the same time I'm sure they would prefer to use the Moon landings as a testbed for the Mars legs, so if it's possible to make them the same design, they should.

36 minutes ago, mikegarrison said:

I tend to doubt they are going to find a way to get good, reliable landing gear inside the engine skirt. They still have the basic problem that when they locked in the design of the engines and the skirt they still had the landing gear on the outside. I suspect that they are probably ultimately going to have to find some way to move the landing gear back outside again.

Yeah, I agree. Deploying entirely from inside is probably too long a pole.

34 minutes ago, mikegarrison said:

Looks more like multiple ways to fail. I'm not trying harsh your mellow or anything, but you've got to keep in mind the engineering rule of making something just as complicated as it needs to be, but no more so.

Nah, I take criticism. No offense taken.

But I do think there's value in separating the dynamic and static loads, if possible. One element is simple and robust and designed for the static load; the other provides the fine control and actuation needed for shock absorption and auto-leveling. With twelve legs instead of six, you could have multiple deployment failures and still stick the landing, assuming the descent was otherwise smooth. Or you could have a very nasty rough landing and damage 3-4 legs and still come out standing.

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The most sensible thing to do with Moon Starship, would be to strip it bare. Remove all aerodynamic surfaces and coverings, fix legs in place and remove retraction mechanisms (of course if they not provide shock-absorbing). Any weight that can be removed is a deltaV profit :) It's not going back into the atmosphere anyway.

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1 hour ago, Scotius said:

The most sensible thing to do with Moon Starship, would be to strip it bare. Remove all aerodynamic surfaces and coverings, fix legs in place and remove retraction mechanisms (of course if they not provide shock-absorbing). Any weight that can be removed is a deltaV profit :) It's not going back into the atmosphere anyway.

The problem with fixing the legs in place is that you still have to launch from Earth once. Think Apollo lander, which had fold-out legs that were never intended to fold back in.

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