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30 minutes ago, RealKerbal3x said:

It seems a lot less complicated than landing on the launch mount to me. They don't need to have a precision of millimetres with this method, if they design it right they should be able to land within a few metres and still reach the target. And the grid fins are already extremely toughly mounted as the 200t booster is literally hanging from them during its 5g reentry, so beefing them up a little more to take the load of the almost empty vehicle is going to be more mass-efficient than adding dedicated legs.

And SpaceX (well, maybe just Elon) wants Super Heavy to be able to fly again an hour after launch, making landing on a separate structure - even if it's movable - out of the question.

(also, congrats on 10,000 posts :D)

The fins is mostly there for steering,  yes they add drag its how they work after all but the high g force is from the rocket engines at the bottom.
Had not thought about grabbing the fins. Well first of the shock will be stronger than just hanging them from the fins and they don't do that lifting falcon 9 first stage either. 
On the other hand it might work however I think you need to beef them up so much legs are lighter. 

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Just now, magnemoe said:

The fins is mostly there for steering,  yes they add drag its how they work after all but the high g force is from the rocket engines at the bottom.
Had not thought about grabbing the fins. Well first of the shock will be stronger than just hanging them from the fins and they don't do that lifting falcon 9 first stage either. 
On the other hand it might work however I think you need to beef them up so much legs are lighter. 

Elon said they were going to grab the booster with the fins, it's not my idea:

 

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11 minutes ago, kerbiloid said:

So, back to the trampoline.

Who makes a bit sense, main issue with catching an capsule if if you miss and hit the boat, this will be much worse than hitting the water. 
That is acceptable for fairings as they are just saved money, they are also huge and lightweight so will not hurt the boat much. 
For an manned capsule it changes. 

And Elron has said some weird stuff like 

Or having cold gas trusters on the upcoming tesla roadster, have fun making the later certified for road use and its an so tiny marked, lets Koenigsegg have it as the spaceX upgrade.
As for robot catgirls, doable as something like an robot waiter there this makes sense, an anime character as its cute but not too human like so trigger uncanny valley.
However Tesla has no experience in humanoid robots.

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On 12/30/2020 at 2:32 PM, magnemoe said:

Grabbing the rocket with the tower, how do you even design this? is it 200 ton super heavy weight? I think he is trolling the no landing on launch clamp crowd. 
Why don't grab it mid air downrange by an flying catgirl. 

WHY NOT INDEED

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A powerful soap bubble generator could help very much with starship landing.

By piercing numerous bubbles on its way one by one, the rocket would decrease its speed almost to zero.

Also it would be washed before landing. It saves time for the ground team.

Additionally, it can save some money by Jebson & Jebson product placement, like "With our Rocket shampoo you fly like a rocket!"

Edited by kerbiloid
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22 minutes ago, RCgothic said:

SN10 is getting stacked! Nearly ready to go even before SN9's flight!

 

 

Is there anything changed between how SN 10 is structured compared to SN8?  (also: isn't SN9 virtually the same build as 8?)

IOW: will SN 10 be showcasing any 'lessons learned' from SN8's flight in terms of physical characteristics - rather than just updating the programming?

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Just now, JoeSchmuckatelli said:

Is there anything changed between how SN 10 is structured compared to SN8?  (also: isn't SN9 virtually the same build as 8?)

SN10 is broadly similar to SN8, but there are probably a few changes here and there. SN9  and SN10 are very similar to SN8 but while some components of SN8 still used the old stainless steel alloy (301), SN9 and 10 are fully built from the new alloy (304L).

1 minute ago, JoeSchmuckatelli said:

IOW: will SN 10 be showcasing any 'lessons learned' from SN8's flight in terms of physical characteristics - rather than just updating the programming?

SN10 began construction before SN8 flew so there probably aren't any major physical changes.

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Chugging right along, as usual. I wonder when they'll start building a proper payload-deploying nose, instead of the plain structural one? Around the time SH1 moves to the mount for testing?

And which SN will be the first to have the three Vactors? Will it also have a cargo nose?

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5 minutes ago, StrandedonEarth said:

Chugging right along, as usual. I wonder when they'll start building a proper payload-deploying nose, instead of the plain structural one? Around the time SH1 moves to the mount for testing?

And which SN will be the first to have the three Vactors? Will it also have a cargo nose?

Elon mentioned that significant changes would be coming around SN15. We don't know what that will entail, but maybe it'll get a payload-deploying nose (as Elon also said a while back that the mid-teens would be the first to orbit) and/or RVacs.

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43 minutes ago, StrandedonEarth said:

Chugging right along, as usual. I wonder when they'll start building a proper payload-deploying nose, instead of the plain structural one? Around the time SH1 moves to the mount for testing?

And which SN will be the first to have the three Vactors? Will it also have a cargo nose?

Probably not, unlike many I think reentry will be harder than the flip and its pointless with an cargo door on something who will not reach orbit. 
Now if its problematic enough they might start launching starlink on the test launches assuming reentry or landing is the issue. 
Think semi disposable. 

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The “catch by the grid fins” idea reminds me of the structural loading design of the Soyuz family of rockets. The four side boosters are suspended from the four payload arms and the sustainer stage hangs off of them while also supporting the upper stage in compression. This works really, really well because it mimics how the loads are distributed in flight: the side boosters are lighter, so the sustainer “hangs” from them in flight while continuing to support the upper stage in compression. 

Elon’s idea isn’t too far from this. The grid fins are supporting a dramatic amount of weight during entry (remember that the booster will have a significant amount of propellant prior to landing) and have to be fixed to the booster with enough strength to provide significant torque and pitch control. I am pretty sure that the booster decelerates by more than one gee during the extremes of re-entry. So they should be more than capable of supporting the weight of an otherwise-empty booster. The combination of hot-gas thrusters and the ability to hover should make that touchdown quite gentle.

What would be REALLY cool would be if the grid fins also provided the primary support during launch. But that might be asking too much. The booster is vastly heavier at launch, and unlike the Soyuz, it is supported in flight entirely from the 28-engine thrust puck.

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Just now, GuessingEveryDay said:

Is it just me, or is that Cybertruck looking small?

It does look a little small, yes, Cybertruck has a width of approximately 2m and Dragon is 3.7m diameter.

It could just be perspective though.

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1 hour ago, CatastrophicFailure said:

Maybe it’s the promised mini-Cybertruck for the European market. :D

Whatever it is, it would make a nice upgrade from the old Apollo lunar rovers. :) Bet you could really kick up some regolith in one of those bad boys.

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8 hours ago, sevenperforce said:

The “catch by the grid fins” idea reminds me of the structural loading design of the Soyuz family of rockets. The four side boosters are suspended from the four payload arms and the sustainer stage hangs off of them while also supporting the upper stage in compression. This works really, really well because it mimics how the loads are distributed in flight: the side boosters are lighter, so the sustainer “hangs” from them in flight while continuing to support the upper stage in compression. 

Elon’s idea isn’t too far from this. The grid fins are supporting a dramatic amount of weight during entry (remember that the booster will have a significant amount of propellant prior to landing) and have to be fixed to the booster with enough strength to provide significant torque and pitch control. I am pretty sure that the booster decelerates by more than one gee during the extremes of re-entry. So they should be more than capable of supporting the weight of an otherwise-empty booster. The combination of hot-gas thrusters and the ability to hover should make that touchdown quite gentle.

What would be REALLY cool would be if the grid fins also provided the primary support during launch. But that might be asking too much. The booster is vastly heavier at launch, and unlike the Soyuz, it is supported in flight entirely from the 28-engine thrust puck.

Well, we'll see if it works. But to me the whole thing is starting to sound like they are getting desperate about figuring out their landing gear issues.

I suppose another concern is that he wants this to be a land/refuel/refly thing, and moving the booster from a landing spot to a launch pad puts a cramp in that. However, the precision required to come down and land exactly where they took off from is pretty crazy. I mean, even a small wind gust could cause a major disaster.

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