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Starship / Super Heavy

faa.gov

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Re: Starship / Super Heavy

#101

Post by basementcat »

woah wrote: post #56
jonplackett wrote: post #15

Earlier quoted context omitted.

He said ‘other competitors’ or something like that and I assumed he meant Tesla despite it being at the time of Apple launch - building gigafactories takes a lot more resources than anything Apple has done so far. Word is Apple won’t even manufacture the whole car anyway like Tesla does.

I wouldn’t be surprised if Apple has produced many times more iPhones by weight than Tesla has produced cars

You inspired me to do some Googling and arithmetic. From the Apple website, an iPhone is about 0.5 lbs. There have been approximately 1.3 billion iPhones sold.

https://www.statista.com/statistics/276306/global-apple-ipho...

A Tesla Model 3 weighs about 4,000 lbs. In the last 6 quarters, about 600,000 vehicles were delivered.

https://www.statista.com/statistics/502208/tesla-quarterly-v...

2.4e9 > 6.5e8

TL;DR: Cars are heavy. The total mass of the vehicles Tesla has delivered in the past six quarters exceeds the total mass of all the iPhones that Apple has ever sold.

Re: Starship / Super Heavy

#102

Post by ateng »

SECProto wrote: post #97
systemvoltage wrote: post #91

Earlier quoted context omitted.

Curious why does it need to wait so long to reorient? I thought it was going to crash and in last few hundred feet, it flipped! Can it orient straight - way up in the air like Falcon boosters?

Reorienting requires the use of main engines. You want to relight them only once, to ensure that the header tanks and the "downcomer" remain full. Additionally you want to burn off as much speed as possible with the bellyflop, so flipping vertical as late as possible. All combined this means combining the landing burn with the flip is best, as close to landing as possible.

It has a cute nickname, “Suicide Burn”.

Why is it efficient? [https://www.reddit.com/r/KerbalSpaceProgram/comments/2z534g/...]

Re: Starship / Super Heavy

#103

Post by SECProto »

flybrand wrote: post #43
mrlonglong wrote: post #21

Earlier quoted context omitted.

What are they going to do with all the brine. It's quite toxic and I don't think it's a good idea to dump that back in the sea.

Brine has set waste disposal costs and methods - near the ocean and with active oil wells nearby there are many options.

Yup. Salinity would be 36 ppt, so for every 1000 tonnes of water they need, they'd produce 2 truck loads of salt (so say maybe 20 truckloads of brine). It's a lot easier to truck out and dispose of 20 loads of brine, than to source and truck in 250 loads of fresh water

Re: Starship / Super Heavy

#104

Post by elihu »

graderjs wrote: post #52

I find it a little weird that FAA handles space stuff. I think they should coordinate, but basically they are for aircraft. There should be a FSA that handles space traffic.

Rockets into space have to transit through the airspace used by regular aircraft, so it kind of makes sense that it would be handled by one agency rather than having two agencies that have to coordinate with each other.

Re: Starship / Super Heavy

#106

Post by SECProto »

basementcat wrote: post #101
woah wrote: post #56

Earlier quoted context omitted.

I wouldn’t be surprised if Apple has produced many times more iPhones by weight than Tesla has produced cars

You inspired me to do some Googling and arithmetic. From the Apple website, an iPhone is about 0.5 lbs. There have been approximately 1.3 billion iPhones sold. https://www.statista.com/statistics/276306/global-apple-ipho... A Tesla Model 3 weighs about 4,000 lbs. In the last 6 quarters, about 600,000 vehicles were delivered. https://www.statista.com/statistics/502208/tesla-quarterly-v... 2.4e9 > 6.5e8 TL;DR: Cars are…

I don't think you need 6 quarters. Using your numbers, 1.3 billion iPhones is 650 million pounds. At 4000lb each, it only takes 163000 model 3s to outweigh the iPhones - about 5 months of production, or two quarters.

Re: Starship / Super Heavy

#107

Post by lemonspat »

dangoldin wrote: post #50

Got lost in a rabbit hole after reading this news. Most incredible thing to me was that due to the reusability the per launch costs may end up being $2M (vs $185 million in 1969–1971 dollars - $1.23 billion in 2019 value for the Saturn V).

Where did you get that $2M number from?

Re: Starship / Super Heavy

#108

Post by graderjs »

elihu wrote: post #104
graderjs wrote: post #52

I find it a little weird that FAA handles space stuff. I think they should coordinate, but basically they are for aircraft. There should be a FSA that handles space traffic.

Rockets into space have to transit through the airspace used by regular aircraft, so it kind of makes sense that it would be handled by one agency rather than having two agencies that have to coordinate with each other.

I disagree. Space is a whole other domain. I don't know FAA mandate but they probably have an altitude cap. All their systems and procedures will not work above a certain zone. We should not put more pressure on them. They have full hands as it is. They should focus on the things they do well.

There should be a FSA that FAA coordinates with for the low altitude region of launch, and above that the FSA handles all sorts of space traffic, satellites, etc.

I don't know anything about this, but probably each launch has to mix between doing their own space window and launch path monitoring, and leaning on some group like NASA. This seems non-ideal. FSA could become the source of this.

I don't think the coordination would pose a blocking challenge. And I think the scope of the space domain warrants its own agency.

Re: Starship / Super Heavy

#109

Post by rlt »

zaroth wrote: post #65
wongarsu wrote: post #53

Earlier quoted context omitted.

The Super Heavy Booster has an order of magnitude more engines than the Starship prototype that did the 12km hop. I don't think Starship can reach orbit without the booster (it can reach space, but not orbital velocity)

Sounds levels in particular will be extreme at launch (as in, deadly even outside the blast radius). And there's a lot more fuel that could potentially explode over populated areas on the way into orbit. For this reason, I think the intent is for Superheavy launches to be mainly done far out at sea. But Boca is needed in the interim for testing purposes.

> And there's a lot more fuel that could potentially explode over populated areas on the way into orbit.

Isn’t that why launch complexes are usually on coasts? They immediately point out over the ocean, and if it’s off course the flight is “terminated” (i.e. exploded) before it reaches populated areas. https://en.m.wikipedia.org/wiki/Range_safety

Re: Starship / Super Heavy

#110

Post by dsp »

lemonspat wrote: post #107
dangoldin wrote: post #50

Got lost in a rabbit hole after reading this news. Most incredible thing to me was that due to the reusability the per launch costs may end up being $2M (vs $185 million in 1969–1971 dollars - $1.23 billion in 2019 value for the Saturn V).

Where did you get that $2M number from?

https://www.space.com/spacex-starship-flight-passenger-cost-...
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