SpaceX plans to send two people around the Moon in late 2018

:confused::confused::confused: Um....er.....Whach you talking about Willis??? :confused::confused::confused::confused:
"Yipee, you're building a rocket."

(Why are you wasting propellant, and therefore payload, to land the booster again?)
Screen Shot 2017-03-06 at 13.12.22.png
 
"Yipee, you're building a rocket."

(Why are you wasting propellant, and therefore payload, to land the booster again?)View attachment 38098

Bro! Do you even Rocket Surgery? How about comparing your posted states to anything else out there instead of just showing SpaceX numbers. Here i'll do it for you. https://en.wikipedia.org/wiki/Comparison_of_orbital_launch_systems

On a purely financial view SpaceX is cheaper by orders of magnitude than anyone else out there.

The company tech is light years ahead of anyone else. Everyone else is LEO. SpaceX equipment is interplanetary. And return to launch site reusable. Who else has that capability?

And finally this is a technology marathon. If we used your logic the wright brothers should have never gotten past kitty hawk because of the useful load on the wright flyer. It takes steps to make this work. Sure they are not moving colony ships today but SpaceX is drinking milk. And while today round trip UL is only a max of 9600, the next iteration will be able to handle even more.

Eventually we'll be at this
7aa7c4748e8da8675fe591e81f9430f5.jpg
 
Bro! Do you even Rocket Surgery? How about comparing your posted states to anything else out there instead of just showing SpaceX numbers. Here i'll do it for you. https://en.wikipedia.org/wiki/Comparison_of_orbital_launch_systems

On a purely financial view SpaceX is cheaper by orders of magnitude than anyone else out there.

The company tech is light years ahead of anyone else. Everyone else is LEO. SpaceX equipment is interplanetary. And return to launch site reusable. Who else has that capability?

And finally this is a technology marathon. If we used your logic the wright brothers should have never gotten past kitty hawk because of the useful load on the wright flyer. It takes steps to make this work. Sure they are not moving colony ships today but SpaceX is drinking milk. And while today round trip UL is only a max of 9600, the next iteration will be able to handle even more.

Eventually we'll be at this
7aa7c4748e8da8675fe591e81f9430f5.jpg


I missed it, SpaceX went to another planet?

Also NASA had return to launch site reusability from 1984 to 2011, in hindsight it wasn't really worth it.
 
To make sure it is clear, the 1 in 60 death statistic goes for ALL manned space flight.

I got that, yeah - but if memory serves the shuttle was a particularly dangerous space vehicle statistically.

355 shuttle astronauts - 14 fatalities... basically almost 4% of all people who ever flew on the shuttle.

There's an awesome MIT OCW on the design of the shuttle, if you haven't watched it you should - its a badass piece of machinery, but I feel that it was engineered by committee. As a result, I feel like it was able to do "a lot" but none of it very cheaply. I wonder how much more robust and reliable it would have been if the air force didn't demand the down range maneuverability capability...
 
I missed it, SpaceX went to another planet?

Also NASA had return to launch site reusability from 1984 to 2011, in hindsight it wasn't really worth it.

I don't know about this - I get the "big dumb booster" argument, but if SpaceX can do it for non-shuttle prices, well then awesome.
 
I missed it, SpaceX went to another planet?

Also NASA had return to launch site reusability from 1984 to 2011, in hindsight it wasn't really worth it.

No but they plan to with existing tech.

And where is the NASA return to launch site now? Yep we retired the shuttle before we had a replacement. but what is your basis for the program not being worth it?
 
No but they plan to with existing tech.

And where is the NASA return to launch site now? Yep we retired the shuttle before we had a replacement. but what is your basis for the program not being worth it?

We've retired every single space program we've had before a replacement flew. At some point you have to reassign the resources, unfortunately the powers that be decided war is more important and ransacked the budget for other things. Yeah I'm mad about it.

I'm sure Elon's done the math and eventually, when the flight rate is high enough, it'll be worth it. But they said the same thing about shuttle and it never achieved the promised flight rate ever in its history (A launch every two weeks, essentially)

My basis for it not being worth it is that it takes almost as many hours to refurbish a re-usable vehicle as it does to just build one, you have new risks that pop up from a vehicle being re-usable in the first place ( See video of STS-93's wild ride into orbit below), and I'm skeptical as to how much worth there is in returning it to the launch site, weight, risk, and cost-wise, versus just parachuting it into the ocean and going to get it. As we've seen, it's payload is halved when you want to return it, meaning half of what it carries is fuel to get it back home.

It strikes me as a contraption. A big giant rocket fuel and energy filled "hey y'all watch this."

The other thing that bothers me is that SpaceX, and any other private space venture launches rockets on science and engineering knowledge funded by your tax dollars and released into the public domain by NASA, an agency under public control, once the knowledge goes private, new stuff is learned, but it's all proprietary. Musk has, in the past, open-sourced stuff so that's heartening, but private industry, in general, doesn't give away stuff for free that it could sell.

TL;DR: Elon's great and all, there's a place for commercial space ventures, but fund NASA.

 
The return to landing/reusable isn't just about reusing the rocket. The tech to land, under power, on a very specific spot is one of the keys to early interplanetary travel.
Getting to Mars, landing and then getting home means the rocket needs to be reusable and thus survive the landing initially.

These are steps in a much larger process, not the ultimate end design.


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My basis for it not being worth it is that it takes almost as many hours to refurbish a re-usable vehicle as it does to just build one, you have new risks that pop up from a vehicle being re-usable in the first place ( See video of STS-93's wild ride into orbit below), and I'm skeptical as to how much worth there is in returning it to the launch site, weight, risk, and cost-wise, versus just parachuting it into the ocean and going to get it. As we've seen, it's payload is halved when you want to return it, meaning half of what it carries is fuel to get it back home.

You got a source for the idea that "it takes as many hours to refurbish as build"? Ocean return is hard on the equipment. Salt water is bad and rocket propellant is bad for the environment.

The other thing that bothers me is that SpaceX, and any other private space venture launches rockets on science and engineering knowledge funded by your tax dollars and released into the public domain by NASA, an agency under public control, once the knowledge goes private, new stuff is learned, but it's all proprietary. Musk has, in the past, open-sourced stuff so that's heartening, but private industry, in general, doesn't give away stuff for free that it could sell.

ITAR applies to NASA just as much as any other American organization, private or public. https://en.wikipedia.org/wiki/International_Traffic_in_Arms_Regulations
SpaceX can't release their tech without being in violation of the law. https://www.reddit.com/r/spacex/wik...sider_releasing_them_like_tesla_motors_did.3F

But then all the knowledge is based on principles from publically available education. SpaceX isn't developing new physics they are just applying new manufacture concepts and new uses for existing material that are his proprietary ideas (and completely acceptable to keep private). No different from proprietary source code.
 
its a badass piece of machinery, but I feel that it was engineered by committee. As a result, I feel like it was able to do "a lot" but none of it very cheaply. I wonder how much more robust and reliable it would have been if the air force didn't demand the down range maneuverability capability...

Part of that was the desire, and likely the need, to sell the program to the DoD for funding purposes. The payload bay size was dictated primarily by DoD needs, and the actual size/shape of the wings could also be attributed to DoD requirements……i.e. 1000 NM cross range travel on re-entry. Not to mention that the entire propulsion configuration was designed to allow for a launch from Vandenberg into polar orbit, and potentially as little as one revolution prior to landing (i.e. the 1000 NM cross range requirement) for the proposed ISR and/or satellite grab missions they had on the table at the time. Obviously that would never occur, but DoD's design needs had pretty disproportionate second and third order effects on the utility and efficiency of the shuttle, which likely would otherwise been much smaller and probably more cost effective.
 
Part of that was the desire, and likely the need, to sell the program to the DoD for funding purposes. The payload bay size was dictated primarily by DoD needs, and the actual size/shape of the wings could also be attributed to DoD requirements……i.e. 1000 NM cross range travel on re-entry. Not to mention that the entire propulsion configuration was designed to allow for a launch from Vandenberg into polar orbit, and potentially as little as one revolution prior to landing (i.e. the 1000 NM cross range requirement) for the proposed ISR and/or satellite grab missions they had on the table at the time. Obviously that would never occur, but DoD's design needs had pretty disproportionate second and third order effects on the utility and efficiency of the shuttle, which likely would otherwise been much smaller and probably more cost effective.

There was also an "Air Force Space Plane" program at the time. Those requirements were all merged into the SST. The ability to bring a payload back should not be underestimated.
 
...It didn't even have to be our satellite.

so, you're telling me folks could go up to orbit, snatch another country's satellite, and bring that heap back down to the alphabet agencies for examination/technological plundering?

Astronauts=space pirates.
 
...It didn't even have to be our satellite.

Which...honestly, I always thought was dumb - or at very least a "relic of a former era." Sure I could see how that could be useful when the satellites were developing film ON the vehicle...but honestly, the second it was apparent that we could do that (which looking at the shuttle would be obvious immediately), the Soviets would start building spy satellites that could "deny" an adversary the ability to capture them (i.e. explode when approached). Also, launches are super high profile, it's not like you're going to get away with launching, replacing a satellite with a duplicate, then coming back without the Russians knowing about it.

Honestly, if anything the shuttle could have used a hell of a lot more dv. The OMS only had about 300m/s of delta v - which isn't really that much. Hell, the Soyuz "lifeboat" at the ISS has 390m/s when it lets go, yeah, I know it's a lot smaller...but damn, dv is important - can you imagine how different things would have been if Columbia could have "aborted on orbit" and gone back to the ISS?

Obviously, inclination changes are different, but a bi-elliptic transfer to an inclination change is a lot easier with an extra 1000m/s or so... If you add delta-v you're more worried about how long your life-support lasts than whether or not you can go where you want to.
 
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