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On 1/5/2022 at 5:43 PM, tater said:

I have my fingers crossed for normal—but all the "land on the launch mount" ideas since the very first BFR announcements have seemed insane to me.

And yet, hear my out, the SpaceX engineers have still built this thing. They're not going by gut feelings. They're not going by "lets build this thing and see if it can catch a descending stage". They are going by a sincere belief that they have built something that, by the numbers, is going to work. So, maybe, since they have built this entire structure, wait and see if it will work.

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41 minutes ago, JoeSchmuckatelli said:

...or watch and rewatch the glorious slo-mo explosion.  Then watch again as they rebuild, and almost get it right.  Then watch yet again as they get it right - and then change everything.

"How not to catch mid air an orbital class booster" by SpaceX, 2023

New Raptor 2 static fires, now from the vertical test stand

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I just watched a video on Starlink and a question hit me.

Whats the breakdown as to why SpaceX never launches more Starlink satellites with a Falcon heavy? 

I'm pretty sure its due to costs... but what are the costs breakdowns compared to how many more satellites you can send up? I'm sure there is a clear cut answer out there somewhere, but idk what it is haha.

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7 minutes ago, MKI said:

I just watched a video on Starlink and a question hit me.

Whats the breakdown as to why SpaceX never launches more Starlink satellites with a Falcon heavy? 

I'm pretty sure its due to costs... but what are the costs breakdowns compared to how many more satellites you can send up? I'm sure there is a clear cut answer out there somewhere, but idk what it is haha.

Well, the first think that comes to my mind is the fairing. Until the extended fairing comes online next year the size is the same as the F9 one, which is usually full of Starlink already (when it has the full complement of 60ish satellites at least)

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Never asked this, but: is Booster tall enough to have the leverage to capsize their current drone ships if caught with some kind of upgraded clamp attached to the drone?

 

Is that why they need the oil rigs?

 

Finally - could one of those Russian Heavy Lift helicopters snatch one off a rig and tote it back to land?

Edited by JoeSchmuckatelli
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16 minutes ago, Beccab said:

Well, the first think that comes to my mind is the fairing. Until the extended fairing comes online next year the size is the same as the F9 one, which is usually full of Starlink already (when it has the full complement of 60ish satellites at least)

They can't just build a bigger faring to maximize the life capabilities? :o

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1 minute ago, MKI said:

They can't just build a bigger faring to maximize the life capabilities? :o

That's what the extended fairing that comes in 2022 for the USAF and the Gateway modules is, but this isn't as in KSP. Most rockets have usually only 1 or 2 fairing sizes, to simplify the aerodynamic profiles and reduce costs

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2 hours ago, MKI said:

I just watched a video on Starlink and a question hit me.

Whats the breakdown as to why SpaceX never launches more Starlink satellites with a Falcon heavy? 

I'm pretty sure its due to costs... but what are the costs breakdowns compared to how many more satellites you can send up? I'm sure there is a clear cut answer out there somewhere, but idk what it is haha.

Falcon Heavy center core is cursed and can never be recovered.

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2 hours ago, MKI said:

I just watched a video on Starlink and a question hit me.

Whats the breakdown as to why SpaceX never launches more Starlink satellites with a Falcon heavy? 

I'm pretty sure its due to costs... but what are the costs breakdowns compared to how many more satellites you can send up? I'm sure there is a clear cut answer out there somewhere, but idk what it is haha.

Agree, also efficiency and that they never been able to recover an core and that they are working on an way more capable rocket. 
Assume SpaxeX see falcon heavy as an dead end  design now, still happy to accept contracts as its the most capable rocket flying today.

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5 hours ago, magnemoe said:

that they never been able to recover an core and that they are working on an way more capable rocket

To be fair it only actually crashed twice, the other time it landed but hard seas sent it out of the drone ship iirc

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Hmm. Look at this picture.

FIWjRPNXEAgXtsN?format=jpg&name=large

 

Do you see the issue there?

Look at how on one edge of the arc the image shows the SH clocked one way, and on the other edge of the arc it is clocked the other way.

That would be super convenient, but if they had enough control to get that kind of precision then they wouldn't be landing out on the edge anyway.

What does it look like if you have the roll controlled and bring in in like it is in the middle, but it drifts laterally?  It looks like at the very least the arm might catch only one grid fin on each side.

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1 hour ago, mikegarrison said:

Hmm. Look at this picture.

FIWjRPNXEAgXtsN?format=jpg&name=large

 

Do you see the issue there?

Look at how on one edge of the arc the image shows the SH clocked one way, and on the other edge of the arc it is clocked the other way.

That would be super convenient, but if they had enough control to get that kind of precision then they wouldn't be landing out on the edge anyway.

What does it look like if you have the roll controlled and bring in in like it is in the middle, but it drifts laterally?  It looks like at the very least the arm might catch only one grid fin on each side.

Not completely angled in the right direction - it is known they have roughly 15 degrees of tolerance on either direction when being caught without missing the hardpoints

I see your point  but personally I'm not worried about rotation being wrong since that's easily controllable separately from the landing with RCS, and grid fins act as the backup in case even that fails (so that they are damaged on the bottom, but the rest of rocket is fine).

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3 hours ago, Beccab said:

Not completely angled in the right direction - it is known they have roughly 15 degrees of tolerance on either direction when being caught without missing the hardpoints

I see your point  but personally I'm not worried about rotation being wrong since that's easily controllable separately from the landing with RCS, and grid fins act as the backup in case even that fails (so that they are damaged on the bottom, but the rest of rocket is fine).

The point is that this guy LunarCaveman seems to have completely not realized that the available catching span is nowhere near as big as he is imagining.

Let's say they have perfect roll control, and bring it down in the exact alignment they intended. In that case, they can only move off the target far enough to create a 15 degree angle, or else they will miss that 15 degree window you refer to.

This whole maneuver is going to be extremely dynamic, and they are going to need very precise landings. We have seen that Falcon 9 usually lands inside that painted circle on the deck, and if they can get that same precision then that should be good enough. But the stakes are a lot higher, because it's not just a barge in the ocean that is at risk -- it's your whole launch tower.

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