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Just now, tater said:

Had to post the larger size, that pic is great

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The NASA PR people have already quietly removed 'World's Largest Rocket Stage' from their SLS infographics.

Superheavy alone is almost as tall as the S-IC and S-II stages, combined.

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3 hours ago, tater said:

He seems to be saying that larger might not be better, however.

The logistics of an even larger vehicle as initially proposed for BFR/ITS would be insane. There's something to be said for the squat designs of the 60s (Boeing LEO, and the various Phil Bono designs like ROMBUS).

It is insane compared to current tech level and commercial or space program's needs. But long term trend for all transport devices is increasing size of units during development. Large size gives generally more advantages than costs.

Maybe 18 m superrocket will be feasible when Starship has been in use for a decade.

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45 minutes ago, Hannu2 said:

It is insane compared to current tech level and commercial or space program's needs. But long term trend for all transport devices is increasing size of units during development. Large size gives generally more advantages than costs.

Maybe 18 m superrocket will be feasible when Starship has been in use for a decade.

One thing I can't wrap my head around with SH is if it blows up its absolutely going to destroy everything. Starship has no launch abort so how is it ever going to be rated for human travel? Full reusability would allow more launches per year at  a cheaper cost and it seems much safer. The N1 was one of the largest non-nuclear explosions in history and it just part of the rocket that exploded. A SH makes N1 look like a childs toy.

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1 minute ago, reducing said:

One thing I can't wrap my head around with SH is if it blows up its absolutely going to destroy everything. Starship has no launch abort so how is it ever going to be rated for human travel? Full reusability would allow more launches per year at  a cheaper cost and it seems much safer. The N1 was one of the largest non-nuclear explosions in history and it just part of the rocket that exploded. A SH makes N1 look like a childs toy.

The plan for crew rating Starship is simply to fly it so many times (hundreds, maybe thousands) that it is considered safe. It's a similar methodology to airliners - rather than designing abort systems, you simply have to accept the tiny risk that has been reduced over time by many flights.

Of course, that will take a long time, probably several years at best. We'll just have to see how it goes.

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12 minutes ago, reducing said:

Starship has no launch abort so how is it ever going to be rated for human travel?

Neither did the Space Shuttle

12 minutes ago, reducing said:

The N1 was one of the largest non-nuclear explosions in history and it just part of the rocket that exploded. A SH makes N1 look like a childs toy.

The saturn V is bigger and more powerful than the N1 too, size isn't really relevant

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6 hours ago, cubinator said:

Lol, they're basically saying:

"The moon lander looks too big, we need to make the moon lander look smaller by building something bigger than it"

Well, they also criticized the use of tankers and multiple dockings for refueling.

If it was 1977 I think it would be a valid concern. But is uncrewed docking really that hard in 2021?

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1 minute ago, SunlitZelkova said:

If it was 1977 I think it would be a valid concern. But is uncrewed docking really that hard in 2021?

The usual suspect here for SLS-fanboy posts literally thinks Earth Orbit Rendezvous of things like SS is more of a risk than LOR for all the Gateway related Rube Goldberg lander concepts. Because reasons.

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16 minutes ago, tater said:

The usual suspect here for SLS-fanboy posts literally thinks Earth Orbit Rendezvous of things like SS is more of a risk than LOR for all the Gateway related Rube Goldberg lander concepts. Because reasons.

Don't forget the five-part Mars sample return mission!

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3 hours ago, reducing said:

One thing I can't wrap my head around with SH is if it blows up its absolutely going to destroy everything. Starship has no launch abort so how is it ever going to be rated for human travel? Full reusability would allow more launches per year at  a cheaper cost and it seems much safer. The N1 was one of the largest non-nuclear explosions in history and it just part of the rocket that exploded. A SH makes N1 look like a childs toy.

While I'm not an expert, I don't think an SH explosion would be quite as bad as you think. Yes, it'll be a bloody big fireball, but that's all it'll be: a fireball. The liquid propellants will mix a little and burn, but it is very unlikely to detonate (supersonic flame propagation) and produce the destructive shockwave seen in Boca Chica, Beirut, Utah, and other places...  I don't want to sound like I'm downplaying how destructive it could be, but it could be worse...

Bear in mind that the Boca Chica explosion of SN4 was caused by a ground equipment interface problem, allowing large amounts of methane to leak, vaporize, and mix with the air before finding the flare stack, creating a fuel-air bomb. An unlikely event during "routine" ops (rocketry should never be routine), and could happen with any vehicle of any size.

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8 hours ago, RCgothic said:

 

 

 

Why is there an enormous seam?  I thought SH was a single booster - so why the obvious break between sections?  

EDIT: okay - I've looked at the subsequent pictures - and the thing I thought was a seam, apparently is not one.  But this pic above makes it look like there's a seam above the ridged portion...  So I now officially ask a different question:  what is the purpose of the ridged portion?

Edited by JoeSchmuckatelli
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9 minutes ago, JoeSchmuckatelli said:

Why is there an enormous seam?  I thought SH was a single booster - so why the obvious break between sections?

Because they cant weld internal stringers where they weld the common dome in place. They need external stringers JUST to cover that small area.

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16 minutes ago, Rakaydos said:

Because they cant weld internal stringers where they weld the common dome in place. They need external stringers JUST to cover that small area.

Huh - so the other ring sections have similar stringers inside?  Interesting.  Makes sense.

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6 hours ago, JoeSchmuckatelli said:

Why is there an enormous seam?  I thought SH was a single booster - so why the obvious break between sections?  

EDIT: okay - I've looked at the subsequent pictures - and the thing I thought was a seam, apparently is not one.  But this pic above makes it look like there's a seam above the ridged portion...  So I now officially ask a different question:  what is the purpose of the ridged portion?

I think the pic they chose for the YouTube thumbnail was of the two parts being stacked. It looks like there is a gap because there literally is a gap. When it's properly mated there isn't.

The ribbed portion is external reinforcement of the common dome area, as has been mentioned.

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