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23 minutes ago, CatastrophicFailure said:

Waaaaaaaat? :blink:

 

That's a bit shocking after all the work they’ve already done there... 

I thought of that place recently. I was wondering what they were going to do with that site, but apparently the ranch in Texas is a better construction site.

Edited by NSEP
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14 minutes ago, Mad Rocket Scientist said:

They must not need to have their design center near their production anymore, since they're not trying to get carbon fiber to work anymore. I wonder if they will continue testing carbon tanks there for future upgrades.

If steel works, there won't be CFC upgrades, it's an entirely different system (hot vs cold structures/TPS, etc).

The business climate is certainly better in TX than CA. CA tends to win out because people would generally prefer to live in CA, so you have lifestyle vs business reality---and even then, that lifestyle preference means it's harder to attract some workers to TX, so that could be an issue. That said, steel work (tanks) is already a thing in TX, they have loads of oil tanks/refineries in the gulf region.

I imagine the engine work will stay in LA, it's just the tank/airframe construction that moves. All the rest can be easily trucked around.

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7 minutes ago, tater said:

The business climate is certainly better in TX than CA. CA tends to win out because people would generally prefer to live in CA, so you have lifestyle vs business reality---and even then, that lifestyle preference means it's harder to attract some workers to TX, so that could be an issue.

If I worked at SpaceX, I’d be ready to relocate anywhere on Earth, even Antarctica.

UPD: Actually, Earth is not the limitation. Moon, Mars and the rest of the Solar System would be fine

Edited by sh1pman
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Old tweet:

Subsections in CA right now... I was looking for a definitive statement that the orbital spacecraft was certainly being built, that was the best I could find. Of course a month ago, maybe that was true.

It could be that they continue to work in CA for a while.

An NSF user provided a link to the company that makes the "tent" structures SpaceX has been using, and they actually exceed Dade County FL hurricane guidelines, and one of their structures was the only large structure in its area that survived hurricane Katrina, apparently (responding to a worry that tents were not a good idea in the gulf coast).

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12 minutes ago, tater said:

An NSF user provided a link to the company that makes the "tent" structures SpaceX has been using, and they actually exceed Dade County FL hurricane guidelines, and one of their structures was the only large structure in its area that survived hurricane Katrina, apparently (responding to a worry that tents were not a good idea in the gulf coast).

Well, its Elon tents. 

Teslatents.

Tensla.

And mk1... arent those 1.25m?

How big would mk3s be?

2 hours ago, tater said:

If steel works, there won't be CFC upgrades, it's an entirely different system (hot vs cold structures/TPS, etc).

The business climate is certainly better in TX than CA. CA tends to win out because people would generally prefer to live in CA, so you have lifestyle vs business reality---and even then, that lifestyle preference means it's harder to attract some workers to TX, so that could be an issue. That said, steel work (tanks) is already a thing in TX, they have loads of oil tanks/refineries in the gulf region.

I imagine the engine work will stay in LA, it's just the tank/airframe construction that moves. All the rest can be easily trucked around.

So metal starship now?

Even for mk1?

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I have another Starship question.  If Dragon propulsive landings have been abandoned due to regulations etc, wont the same issue be present for Starship?  Or will it still propulsive land with people?  

Also if Starship has no cargo can it SSTO?  I'm guessing not but I might as well ask :cool:

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18 minutes ago, Rus-Evo said:

I have another Starship question.  If Dragon propulsive landings have been abandoned due to regulations etc, wont the same issue be present for Starship?  Or will it still propulsive land with people?  

Also if Starship has no cargo can it SSTO?  I'm guessing not but I might as well ask :cool:

Short answer: no, those regulation issues won’t apply because Starship is not a NASA program. Propulsive landing on D2 is “easily” feasible from a technical/engineering standpoint, but getting NASA to OK that is the real hurdle. Basically, with D2 already having a limited lifespan with the coming of Starship, it’s not worth the trouble for SpaceX. 

Propulsively landing a Starship full of people, now... there are many regulatory unknowns that remain on this, a lot of it will literally have to be made up as they go along because there’s simply no precedent for any such thing yet. I expect there will be many (successful) cargo Starship flights before we ever see one with people on board. With full reuse, that “many” can take place a lot quicker than many may expect. 

Last I heard, the final orbital Starship will theoretically be capable of SSTO launch, but with no cargo or fuel to land, so there’s really no point even in demonstrating it. Also, this may have changed with all the other recent changes to the design.  :confused:

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50 minutes ago, CatastrophicFailure said:

Last I heard, the final orbital Starship will theoretically be capable of SSTO launch, but with no cargo or fuel to land, so there’s really no point even in demonstrating it. Also, this may have changed with all the other recent changes to the design.  :confused:

They were able to increase Falcon 9's efficiency by a huge amount. I think it's possible we could eventually see a single-stage Starship with F9-like payload capacity and full reusability. This will take a while, though. And it might not make sense to do that when you can just pack a bunch of stuff into the Starship's giant cargo bay in the two-stage variant.

Edited by cubinator
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39 minutes ago, Rus-Evo said:

can it SSTO?

You can check for yourself :

http://www.quantumg.net/rocketeq.html

Initial mass (m0)  is 1100 + 85 = 1185 tonnes

Final mass (m1) is 85 tonnes

Isp (isp) is 330 seconds at sea=level, 356 seconds at vacuum, so you have to use a flight average to get a reasonable result.

Try 345 or 350 seconds. Normally i'd use 345 seconds for the 2017/18 raptor

You cant use 356. Thats cheating. Only scammers try to use vacuum isp at sea level.

 

For 350 seconds, i hit the recalc button next to deltaV (dv) and get 9037 meters/second.

Thats not quite enough for orbit from the cape. Korou maybe.

You need around 9200 m/s from cape or brownsville (this assumes a liftoff twr>1.30)

Stick 9200 in the deltaV box, and hit recalc on the final mass box.

I get about 81 tonnes.

So starship needs to come in under 81 tonnes dry if it wants to get to orbit from brownsville.

And payload will be zero.

So you cant deorbit (costs ~150m/s, or 4 tonnes), reenter (5  to  10 tons of methane coolant payload....not sure at present), and land (250 m/s or 7 tonnes)

 

A problem is your takeoff twr.

7 raptors at sealevel is about 1400 tonnes of thrust.

So your liftoff twr is 1400/1185 = 1.18

This is very low. Think saturn V take off.

Anything less than about 1.3 is going to incur increasing gravity losses, and these bump up your required deltaV.

You are wasting fuel by going too slow.

What to do? Add an engine...no

Reduce propellant...cant you need every drop.

Run engines at 110% power...risky but your only option.

 

Its a fun exercise.

But elon warned us and the rocket equation always has the final word.

SSTO on earth is useless.

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